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webrtc 官方linux demo 改装采集器

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dongl 2024-01-17 21:24:41 +08:00
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cmake_minimum_required(VERSION 3.26)
project(video_call)
set(CMAKE_CXX_STANDARD 17)
add_compile_options(-std=c++17)
# 预编译宏
add_definitions(-DWEBRTC_POSIX -DWEBRTC_MAC)
# -DWEBRTC_LINUX
# 系统库文件
find_package(PkgConfig REQUIRED)
pkg_check_modules(GTK3 REQUIRED gtk+-3.0)
pkg_check_modules(JSONCPP REQUIRED jsoncpp)
pkg_check_modules(FFMPEG REQUIRED IMPORTED_TARGET
libavcodec
libswresample
libavdevice
libavfilter
libavformat
libavutil
libpostproc
libswscale
)
#find_package(GTK3 REQUIRED)
#find_package(JSONCPP REQUIRED)
# macos sdk
find_library(COCOA_LIBRARY Cocoa)
find_library(CORE_AUDIO_LIBRARY CoreAudio)
find_library(CORE_VIDEO_LIBRARY CoreVideo)
find_library(AUDIO_TOOLBOX_LIBRARY AudioToolbox)
find_library(AUDIO_TOOLBOX_UNIT AudioUnit)
find_library(CORE_MEDIA_LIBRARY CoreMedia)
find_library(AVFOUNDATION_LIBRARY AVFoundation)
# 系统库文件
include_directories(/opt/homebrew/include)
include_directories(/opt/homebrew/include/cairo)
include_directories(/opt/homebrew/include/gdk-pixbuf-2.0)
include_directories(/opt/homebrew/include/gtk-3.0)
include_directories(/opt/homebrew/include/gtk)
include_directories(/opt/homebrew/include/pango-1.0)
include_directories(/opt/homebrew/include/glib-2.0)
include_directories(/opt/homebrew/include/glib-2.0/glib)
include_directories(/opt/homebrew/include/atk-1.0)
include_directories(${JSONCPP_INCLUDE_DIRS})
include_directories(${GTK3_INCLUDE_DIRS})
# 项目内
include_directories(${CMAKE_SOURCE_DIR}/include)
include_directories(${CMAKE_SOURCE_DIR}/include/absl)
include_directories(${CMAKE_SOURCE_DIR}/include/webrtc_cxx_sdk)
include_directories(${CMAKE_SOURCE_DIR}/include/webrtc_cxx_sdk/third_party/ffmpeg)
#include_directories(/Users/dongl/tools/ffmpeg/ffmpeg_build/include)
include_directories(${CMAKE_SOURCE_DIR}/include/webrtc_cxx_sdk/third_party/harfbuzz-ng/src/src)
include_directories(${CMAKE_SOURCE_DIR}/include/webrtc_cxx_sdk/third_party/libyuv/include)
# 打印路径
message( ${GTK3_LIBRARY_DIRS})
message( ${JSONCPP_LIBRARY_DIRS})
message( ${COCOA_LIBRARY})
message( ${CORE_AUDIO_LIBRARY})
message( ${AUDIO_TOOLBOX_LIBRARY})
message( ${AUDIO_TOOLBOX_UNIT})
message( ${CORE_MEDIA_LIBRARY})
message( ${AVFOUNDATION_LIBRARY})
# 链接库
link_directories(${CMAKE_SOURCE_DIR}/lib/arm_macos)
link_directories(/opt/homebrew/lib)
link_directories(/opt/homebrew/Cellar/ffmpeg/6.0_1/lib)
#link_directories(/Users/dongl/tools/ffmpeg/ffmpeg_build/lib)
add_subdirectory(src/client)
add_subdirectory(src/server)
add_subdirectory(src/test)

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: algorithm.h
// -----------------------------------------------------------------------------
//
// This header file contains Google extensions to the standard <algorithm> C++
// header.
#ifndef ABSL_ALGORITHM_ALGORITHM_H_
#define ABSL_ALGORITHM_ALGORITHM_H_
#include <algorithm>
#include <iterator>
#include <type_traits>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
// equal()
// rotate()
//
// Historical note: Abseil once provided implementations of these algorithms
// prior to their adoption in C++14. New code should prefer to use the std
// variants.
//
// See the documentation for the STL <algorithm> header for more information:
// https://en.cppreference.com/w/cpp/header/algorithm
using std::equal;
using std::rotate;
// linear_search()
//
// Performs a linear search for `value` using the iterator `first` up to
// but not including `last`, returning true if [`first`, `last`) contains an
// element equal to `value`.
//
// A linear search is of O(n) complexity which is guaranteed to make at most
// n = (`last` - `first`) comparisons. A linear search over short containers
// may be faster than a binary search, even when the container is sorted.
template <typename InputIterator, typename EqualityComparable>
bool linear_search(InputIterator first, InputIterator last,
const EqualityComparable& value) {
return std::find(first, last, value) != last;
}
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_ALGORITHM_ALGORITHM_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// This header file defines macros for declaring attributes for functions,
// types, and variables.
//
// These macros are used within Abseil and allow the compiler to optimize, where
// applicable, certain function calls.
//
// Most macros here are exposing GCC or Clang features, and are stubbed out for
// other compilers.
//
// GCC attributes documentation:
// https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Function-Attributes.html
// https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Variable-Attributes.html
// https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Type-Attributes.html
//
// Most attributes in this file are already supported by GCC 4.7. However, some
// of them are not supported in older version of Clang. Thus, we check
// `__has_attribute()` first. If the check fails, we check if we are on GCC and
// assume the attribute exists on GCC (which is verified on GCC 4.7).
#ifndef ABSL_BASE_ATTRIBUTES_H_
#define ABSL_BASE_ATTRIBUTES_H_
#include "absl/base/config.h"
// ABSL_HAVE_ATTRIBUTE
//
// A function-like feature checking macro that is a wrapper around
// `__has_attribute`, which is defined by GCC 5+ and Clang and evaluates to a
// nonzero constant integer if the attribute is supported or 0 if not.
//
// It evaluates to zero if `__has_attribute` is not defined by the compiler.
//
// GCC: https://gcc.gnu.org/gcc-5/changes.html
// Clang: https://clang.llvm.org/docs/LanguageExtensions.html
#ifdef __has_attribute
#define ABSL_HAVE_ATTRIBUTE(x) __has_attribute(x)
#else
#define ABSL_HAVE_ATTRIBUTE(x) 0
#endif
// ABSL_HAVE_CPP_ATTRIBUTE
//
// A function-like feature checking macro that accepts C++11 style attributes.
// It's a wrapper around `__has_cpp_attribute`, defined by ISO C++ SD-6
// (https://en.cppreference.com/w/cpp/experimental/feature_test). If we don't
// find `__has_cpp_attribute`, will evaluate to 0.
#if defined(__cplusplus) && defined(__has_cpp_attribute)
// NOTE: requiring __cplusplus above should not be necessary, but
// works around https://bugs.llvm.org/show_bug.cgi?id=23435.
#define ABSL_HAVE_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
#else
#define ABSL_HAVE_CPP_ATTRIBUTE(x) 0
#endif
// -----------------------------------------------------------------------------
// Function Attributes
// -----------------------------------------------------------------------------
//
// GCC: https://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html
// Clang: https://clang.llvm.org/docs/AttributeReference.html
// ABSL_PRINTF_ATTRIBUTE
// ABSL_SCANF_ATTRIBUTE
//
// Tells the compiler to perform `printf` format string checking if the
// compiler supports it; see the 'format' attribute in
// <https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Function-Attributes.html>.
//
// Note: As the GCC manual states, "[s]ince non-static C++ methods
// have an implicit 'this' argument, the arguments of such methods
// should be counted from two, not one."
#if ABSL_HAVE_ATTRIBUTE(format) || (defined(__GNUC__) && !defined(__clang__))
#define ABSL_PRINTF_ATTRIBUTE(string_index, first_to_check) \
__attribute__((__format__(__printf__, string_index, first_to_check)))
#define ABSL_SCANF_ATTRIBUTE(string_index, first_to_check) \
__attribute__((__format__(__scanf__, string_index, first_to_check)))
#else
#define ABSL_PRINTF_ATTRIBUTE(string_index, first_to_check)
#define ABSL_SCANF_ATTRIBUTE(string_index, first_to_check)
#endif
// ABSL_ATTRIBUTE_ALWAYS_INLINE
// ABSL_ATTRIBUTE_NOINLINE
//
// Forces functions to either inline or not inline. Introduced in gcc 3.1.
#if ABSL_HAVE_ATTRIBUTE(always_inline) || \
(defined(__GNUC__) && !defined(__clang__))
#define ABSL_ATTRIBUTE_ALWAYS_INLINE __attribute__((always_inline))
#define ABSL_HAVE_ATTRIBUTE_ALWAYS_INLINE 1
#else
#define ABSL_ATTRIBUTE_ALWAYS_INLINE
#endif
#if ABSL_HAVE_ATTRIBUTE(noinline) || (defined(__GNUC__) && !defined(__clang__))
#define ABSL_ATTRIBUTE_NOINLINE __attribute__((noinline))
#define ABSL_HAVE_ATTRIBUTE_NOINLINE 1
#else
#define ABSL_ATTRIBUTE_NOINLINE
#endif
// ABSL_ATTRIBUTE_NO_TAIL_CALL
//
// Prevents the compiler from optimizing away stack frames for functions which
// end in a call to another function.
#if ABSL_HAVE_ATTRIBUTE(disable_tail_calls)
#define ABSL_HAVE_ATTRIBUTE_NO_TAIL_CALL 1
#define ABSL_ATTRIBUTE_NO_TAIL_CALL __attribute__((disable_tail_calls))
#elif defined(__GNUC__) && !defined(__clang__) && !defined(__e2k__)
#define ABSL_HAVE_ATTRIBUTE_NO_TAIL_CALL 1
#define ABSL_ATTRIBUTE_NO_TAIL_CALL \
__attribute__((optimize("no-optimize-sibling-calls")))
#else
#define ABSL_ATTRIBUTE_NO_TAIL_CALL
#define ABSL_HAVE_ATTRIBUTE_NO_TAIL_CALL 0
#endif
// ABSL_ATTRIBUTE_WEAK
//
// Tags a function as weak for the purposes of compilation and linking.
// Weak attributes did not work properly in LLVM's Windows backend before
// 9.0.0, so disable them there. See https://bugs.llvm.org/show_bug.cgi?id=37598
// for further information.
// The MinGW compiler doesn't complain about the weak attribute until the link
// step, presumably because Windows doesn't use ELF binaries.
#if (ABSL_HAVE_ATTRIBUTE(weak) || \
(defined(__GNUC__) && !defined(__clang__))) && \
(!defined(_WIN32) || (defined(__clang__) && __clang_major__ >= 9)) && \
!defined(__MINGW32__)
#undef ABSL_ATTRIBUTE_WEAK
#define ABSL_ATTRIBUTE_WEAK __attribute__((weak))
#define ABSL_HAVE_ATTRIBUTE_WEAK 1
#else
#define ABSL_ATTRIBUTE_WEAK
#define ABSL_HAVE_ATTRIBUTE_WEAK 0
#endif
// ABSL_ATTRIBUTE_NONNULL
//
// Tells the compiler either (a) that a particular function parameter
// should be a non-null pointer, or (b) that all pointer arguments should
// be non-null.
//
// Note: As the GCC manual states, "[s]ince non-static C++ methods
// have an implicit 'this' argument, the arguments of such methods
// should be counted from two, not one."
//
// Args are indexed starting at 1.
//
// For non-static class member functions, the implicit `this` argument
// is arg 1, and the first explicit argument is arg 2. For static class member
// functions, there is no implicit `this`, and the first explicit argument is
// arg 1.
//
// Example:
//
// /* arg_a cannot be null, but arg_b can */
// void Function(void* arg_a, void* arg_b) ABSL_ATTRIBUTE_NONNULL(1);
//
// class C {
// /* arg_a cannot be null, but arg_b can */
// void Method(void* arg_a, void* arg_b) ABSL_ATTRIBUTE_NONNULL(2);
//
// /* arg_a cannot be null, but arg_b can */
// static void StaticMethod(void* arg_a, void* arg_b)
// ABSL_ATTRIBUTE_NONNULL(1);
// };
//
// If no arguments are provided, then all pointer arguments should be non-null.
//
// /* No pointer arguments may be null. */
// void Function(void* arg_a, void* arg_b, int arg_c) ABSL_ATTRIBUTE_NONNULL();
//
// NOTE: The GCC nonnull attribute actually accepts a list of arguments, but
// ABSL_ATTRIBUTE_NONNULL does not.
#if ABSL_HAVE_ATTRIBUTE(nonnull) || (defined(__GNUC__) && !defined(__clang__))
#define ABSL_ATTRIBUTE_NONNULL(arg_index) __attribute__((nonnull(arg_index)))
#else
#define ABSL_ATTRIBUTE_NONNULL(...)
#endif
// ABSL_ATTRIBUTE_NORETURN
//
// Tells the compiler that a given function never returns.
#if ABSL_HAVE_ATTRIBUTE(noreturn) || (defined(__GNUC__) && !defined(__clang__))
#define ABSL_ATTRIBUTE_NORETURN __attribute__((noreturn))
#elif defined(_MSC_VER)
#define ABSL_ATTRIBUTE_NORETURN __declspec(noreturn)
#else
#define ABSL_ATTRIBUTE_NORETURN
#endif
// ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS
//
// Tells the AddressSanitizer (or other memory testing tools) to ignore a given
// function. Useful for cases when a function reads random locations on stack,
// calls _exit from a cloned subprocess, deliberately accesses buffer
// out of bounds or does other scary things with memory.
// NOTE: GCC supports AddressSanitizer(asan) since 4.8.
// https://gcc.gnu.org/gcc-4.8/changes.html
#if defined(ABSL_HAVE_ADDRESS_SANITIZER) && \
ABSL_HAVE_ATTRIBUTE(no_sanitize_address)
#define ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address))
#elif defined(ABSL_HAVE_ADDRESS_SANITIZER) && defined(_MSC_VER) && \
_MSC_VER >= 1928
// https://docs.microsoft.com/en-us/cpp/cpp/no-sanitize-address
#define ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS __declspec(no_sanitize_address)
#elif defined(ABSL_HAVE_HWADDRESS_SANITIZER) && ABSL_HAVE_ATTRIBUTE(no_sanitize)
// HWAddressSanitizer is a sanitizer similar to AddressSanitizer, which uses CPU
// features to detect similar bugs with less CPU and memory overhead.
// NOTE: GCC supports HWAddressSanitizer(hwasan) since 11.
// https://gcc.gnu.org/gcc-11/changes.html
#define ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS \
__attribute__((no_sanitize("hwaddress")))
#else
#define ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS
#endif
// ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY
//
// Tells the MemorySanitizer to relax the handling of a given function. All "Use
// of uninitialized value" warnings from such functions will be suppressed, and
// all values loaded from memory will be considered fully initialized. This
// attribute is similar to the ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS attribute
// above, but deals with initialized-ness rather than addressability issues.
// NOTE: MemorySanitizer(msan) is supported by Clang but not GCC.
#if ABSL_HAVE_ATTRIBUTE(no_sanitize_memory)
#define ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY __attribute__((no_sanitize_memory))
#else
#define ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY
#endif
// ABSL_ATTRIBUTE_NO_SANITIZE_THREAD
//
// Tells the ThreadSanitizer to not instrument a given function.
// NOTE: GCC supports ThreadSanitizer(tsan) since 4.8.
// https://gcc.gnu.org/gcc-4.8/changes.html
#if ABSL_HAVE_ATTRIBUTE(no_sanitize_thread)
#define ABSL_ATTRIBUTE_NO_SANITIZE_THREAD __attribute__((no_sanitize_thread))
#else
#define ABSL_ATTRIBUTE_NO_SANITIZE_THREAD
#endif
// ABSL_ATTRIBUTE_NO_SANITIZE_UNDEFINED
//
// Tells the UndefinedSanitizer to ignore a given function. Useful for cases
// where certain behavior (eg. division by zero) is being used intentionally.
// NOTE: GCC supports UndefinedBehaviorSanitizer(ubsan) since 4.9.
// https://gcc.gnu.org/gcc-4.9/changes.html
#if ABSL_HAVE_ATTRIBUTE(no_sanitize_undefined)
#define ABSL_ATTRIBUTE_NO_SANITIZE_UNDEFINED \
__attribute__((no_sanitize_undefined))
#elif ABSL_HAVE_ATTRIBUTE(no_sanitize)
#define ABSL_ATTRIBUTE_NO_SANITIZE_UNDEFINED \
__attribute__((no_sanitize("undefined")))
#else
#define ABSL_ATTRIBUTE_NO_SANITIZE_UNDEFINED
#endif
// ABSL_ATTRIBUTE_NO_SANITIZE_CFI
//
// Tells the ControlFlowIntegrity sanitizer to not instrument a given function.
// See https://clang.llvm.org/docs/ControlFlowIntegrity.html for details.
#if ABSL_HAVE_ATTRIBUTE(no_sanitize) && defined(__llvm__)
#define ABSL_ATTRIBUTE_NO_SANITIZE_CFI __attribute__((no_sanitize("cfi")))
#else
#define ABSL_ATTRIBUTE_NO_SANITIZE_CFI
#endif
// ABSL_ATTRIBUTE_NO_SANITIZE_SAFESTACK
//
// Tells the SafeStack to not instrument a given function.
// See https://clang.llvm.org/docs/SafeStack.html for details.
#if ABSL_HAVE_ATTRIBUTE(no_sanitize)
#define ABSL_ATTRIBUTE_NO_SANITIZE_SAFESTACK \
__attribute__((no_sanitize("safe-stack")))
#else
#define ABSL_ATTRIBUTE_NO_SANITIZE_SAFESTACK
#endif
// ABSL_ATTRIBUTE_RETURNS_NONNULL
//
// Tells the compiler that a particular function never returns a null pointer.
#if ABSL_HAVE_ATTRIBUTE(returns_nonnull)
#define ABSL_ATTRIBUTE_RETURNS_NONNULL __attribute__((returns_nonnull))
#else
#define ABSL_ATTRIBUTE_RETURNS_NONNULL
#endif
// ABSL_HAVE_ATTRIBUTE_SECTION
//
// Indicates whether labeled sections are supported. Weak symbol support is
// a prerequisite. Labeled sections are not supported on Darwin/iOS.
#ifdef ABSL_HAVE_ATTRIBUTE_SECTION
#error ABSL_HAVE_ATTRIBUTE_SECTION cannot be directly set
#elif (ABSL_HAVE_ATTRIBUTE(section) || \
(defined(__GNUC__) && !defined(__clang__))) && \
!defined(__APPLE__) && ABSL_HAVE_ATTRIBUTE_WEAK
#define ABSL_HAVE_ATTRIBUTE_SECTION 1
// ABSL_ATTRIBUTE_SECTION
//
// Tells the compiler/linker to put a given function into a section and define
// `__start_ ## name` and `__stop_ ## name` symbols to bracket the section.
// This functionality is supported by GNU linker. Any function annotated with
// `ABSL_ATTRIBUTE_SECTION` must not be inlined, or it will be placed into
// whatever section its caller is placed into.
//
#ifndef ABSL_ATTRIBUTE_SECTION
#define ABSL_ATTRIBUTE_SECTION(name) \
__attribute__((section(#name))) __attribute__((noinline))
#endif
// ABSL_ATTRIBUTE_SECTION_VARIABLE
//
// Tells the compiler/linker to put a given variable into a section and define
// `__start_ ## name` and `__stop_ ## name` symbols to bracket the section.
// This functionality is supported by GNU linker.
#ifndef ABSL_ATTRIBUTE_SECTION_VARIABLE
#ifdef _AIX
// __attribute__((section(#name))) on AIX is achieved by using the `.csect`
// psudo op which includes an additional integer as part of its syntax indcating
// alignment. If data fall under different alignments then you might get a
// compilation error indicating a `Section type conflict`.
#define ABSL_ATTRIBUTE_SECTION_VARIABLE(name)
#else
#define ABSL_ATTRIBUTE_SECTION_VARIABLE(name) __attribute__((section(#name)))
#endif
#endif
// ABSL_DECLARE_ATTRIBUTE_SECTION_VARS
//
// A weak section declaration to be used as a global declaration
// for ABSL_ATTRIBUTE_SECTION_START|STOP(name) to compile and link
// even without functions with ABSL_ATTRIBUTE_SECTION(name).
// ABSL_DEFINE_ATTRIBUTE_SECTION should be in the exactly one file; it's
// a no-op on ELF but not on Mach-O.
//
#ifndef ABSL_DECLARE_ATTRIBUTE_SECTION_VARS
#define ABSL_DECLARE_ATTRIBUTE_SECTION_VARS(name) \
extern char __start_##name[] ABSL_ATTRIBUTE_WEAK; \
extern char __stop_##name[] ABSL_ATTRIBUTE_WEAK
#endif
#ifndef ABSL_DEFINE_ATTRIBUTE_SECTION_VARS
#define ABSL_INIT_ATTRIBUTE_SECTION_VARS(name)
#define ABSL_DEFINE_ATTRIBUTE_SECTION_VARS(name)
#endif
// ABSL_ATTRIBUTE_SECTION_START
//
// Returns `void*` pointers to start/end of a section of code with
// functions having ABSL_ATTRIBUTE_SECTION(name).
// Returns 0 if no such functions exist.
// One must ABSL_DECLARE_ATTRIBUTE_SECTION_VARS(name) for this to compile and
// link.
//
#define ABSL_ATTRIBUTE_SECTION_START(name) \
(reinterpret_cast<void *>(__start_##name))
#define ABSL_ATTRIBUTE_SECTION_STOP(name) \
(reinterpret_cast<void *>(__stop_##name))
#else // !ABSL_HAVE_ATTRIBUTE_SECTION
#define ABSL_HAVE_ATTRIBUTE_SECTION 0
// provide dummy definitions
#define ABSL_ATTRIBUTE_SECTION(name)
#define ABSL_ATTRIBUTE_SECTION_VARIABLE(name)
#define ABSL_INIT_ATTRIBUTE_SECTION_VARS(name)
#define ABSL_DEFINE_ATTRIBUTE_SECTION_VARS(name)
#define ABSL_DECLARE_ATTRIBUTE_SECTION_VARS(name)
#define ABSL_ATTRIBUTE_SECTION_START(name) (reinterpret_cast<void *>(0))
#define ABSL_ATTRIBUTE_SECTION_STOP(name) (reinterpret_cast<void *>(0))
#endif // ABSL_ATTRIBUTE_SECTION
// ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC
//
// Support for aligning the stack on 32-bit x86.
#if ABSL_HAVE_ATTRIBUTE(force_align_arg_pointer) || \
(defined(__GNUC__) && !defined(__clang__))
#if defined(__i386__)
#define ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC \
__attribute__((force_align_arg_pointer))
#define ABSL_REQUIRE_STACK_ALIGN_TRAMPOLINE (0)
#elif defined(__x86_64__)
#define ABSL_REQUIRE_STACK_ALIGN_TRAMPOLINE (1)
#define ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC
#else // !__i386__ && !__x86_64
#define ABSL_REQUIRE_STACK_ALIGN_TRAMPOLINE (0)
#define ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC
#endif // __i386__
#else
#define ABSL_ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC
#define ABSL_REQUIRE_STACK_ALIGN_TRAMPOLINE (0)
#endif
// ABSL_MUST_USE_RESULT
//
// Tells the compiler to warn about unused results.
//
// For code or headers that are assured to only build with C++17 and up, prefer
// just using the standard `[[nodiscard]]` directly over this macro.
//
// When annotating a function, it must appear as the first part of the
// declaration or definition. The compiler will warn if the return value from
// such a function is unused:
//
// ABSL_MUST_USE_RESULT Sprocket* AllocateSprocket();
// AllocateSprocket(); // Triggers a warning.
//
// When annotating a class, it is equivalent to annotating every function which
// returns an instance.
//
// class ABSL_MUST_USE_RESULT Sprocket {};
// Sprocket(); // Triggers a warning.
//
// Sprocket MakeSprocket();
// MakeSprocket(); // Triggers a warning.
//
// Note that references and pointers are not instances:
//
// Sprocket* SprocketPointer();
// SprocketPointer(); // Does *not* trigger a warning.
//
// ABSL_MUST_USE_RESULT allows using cast-to-void to suppress the unused result
// warning. For that, warn_unused_result is used only for clang but not for gcc.
// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66425
//
// Note: past advice was to place the macro after the argument list.
//
// TODO(b/176172494): Use ABSL_HAVE_CPP_ATTRIBUTE(nodiscard) when all code is
// compliant with the stricter [[nodiscard]].
#if defined(__clang__) && ABSL_HAVE_ATTRIBUTE(warn_unused_result)
#define ABSL_MUST_USE_RESULT __attribute__((warn_unused_result))
#else
#define ABSL_MUST_USE_RESULT
#endif
// ABSL_ATTRIBUTE_HOT, ABSL_ATTRIBUTE_COLD
//
// Tells GCC that a function is hot or cold. GCC can use this information to
// improve static analysis, i.e. a conditional branch to a cold function
// is likely to be not-taken.
// This annotation is used for function declarations.
//
// Example:
//
// int foo() ABSL_ATTRIBUTE_HOT;
#if ABSL_HAVE_ATTRIBUTE(hot) || (defined(__GNUC__) && !defined(__clang__))
#define ABSL_ATTRIBUTE_HOT __attribute__((hot))
#else
#define ABSL_ATTRIBUTE_HOT
#endif
#if ABSL_HAVE_ATTRIBUTE(cold) || (defined(__GNUC__) && !defined(__clang__))
#define ABSL_ATTRIBUTE_COLD __attribute__((cold))
#else
#define ABSL_ATTRIBUTE_COLD
#endif
// ABSL_XRAY_ALWAYS_INSTRUMENT, ABSL_XRAY_NEVER_INSTRUMENT, ABSL_XRAY_LOG_ARGS
//
// We define the ABSL_XRAY_ALWAYS_INSTRUMENT and ABSL_XRAY_NEVER_INSTRUMENT
// macro used as an attribute to mark functions that must always or never be
// instrumented by XRay. Currently, this is only supported in Clang/LLVM.
//
// For reference on the LLVM XRay instrumentation, see
// http://llvm.org/docs/XRay.html.
//
// A function with the XRAY_ALWAYS_INSTRUMENT macro attribute in its declaration
// will always get the XRay instrumentation sleds. These sleds may introduce
// some binary size and runtime overhead and must be used sparingly.
//
// These attributes only take effect when the following conditions are met:
//
// * The file/target is built in at least C++11 mode, with a Clang compiler
// that supports XRay attributes.
// * The file/target is built with the -fxray-instrument flag set for the
// Clang/LLVM compiler.
// * The function is defined in the translation unit (the compiler honors the
// attribute in either the definition or the declaration, and must match).
//
// There are cases when, even when building with XRay instrumentation, users
// might want to control specifically which functions are instrumented for a
// particular build using special-case lists provided to the compiler. These
// special case lists are provided to Clang via the
// -fxray-always-instrument=... and -fxray-never-instrument=... flags. The
// attributes in source take precedence over these special-case lists.
//
// To disable the XRay attributes at build-time, users may define
// ABSL_NO_XRAY_ATTRIBUTES. Do NOT define ABSL_NO_XRAY_ATTRIBUTES on specific
// packages/targets, as this may lead to conflicting definitions of functions at
// link-time.
//
// XRay isn't currently supported on Android:
// https://github.com/android/ndk/issues/368
#if ABSL_HAVE_CPP_ATTRIBUTE(clang::xray_always_instrument) && \
!defined(ABSL_NO_XRAY_ATTRIBUTES) && !defined(__ANDROID__)
#define ABSL_XRAY_ALWAYS_INSTRUMENT [[clang::xray_always_instrument]]
#define ABSL_XRAY_NEVER_INSTRUMENT [[clang::xray_never_instrument]]
#if ABSL_HAVE_CPP_ATTRIBUTE(clang::xray_log_args)
#define ABSL_XRAY_LOG_ARGS(N) \
[[clang::xray_always_instrument, clang::xray_log_args(N)]]
#else
#define ABSL_XRAY_LOG_ARGS(N) [[clang::xray_always_instrument]]
#endif
#else
#define ABSL_XRAY_ALWAYS_INSTRUMENT
#define ABSL_XRAY_NEVER_INSTRUMENT
#define ABSL_XRAY_LOG_ARGS(N)
#endif
// ABSL_ATTRIBUTE_REINITIALIZES
//
// Indicates that a member function reinitializes the entire object to a known
// state, independent of the previous state of the object.
//
// The clang-tidy check bugprone-use-after-move allows member functions marked
// with this attribute to be called on objects that have been moved from;
// without the attribute, this would result in a use-after-move warning.
#if ABSL_HAVE_CPP_ATTRIBUTE(clang::reinitializes)
#define ABSL_ATTRIBUTE_REINITIALIZES [[clang::reinitializes]]
#else
#define ABSL_ATTRIBUTE_REINITIALIZES
#endif
// -----------------------------------------------------------------------------
// Variable Attributes
// -----------------------------------------------------------------------------
// ABSL_ATTRIBUTE_UNUSED
//
// Prevents the compiler from complaining about variables that appear unused.
//
// For code or headers that are assured to only build with C++17 and up, prefer
// just using the standard '[[maybe_unused]]' directly over this macro.
//
// Due to differences in positioning requirements between the old, compiler
// specific __attribute__ syntax and the now standard [[maybe_unused]], this
// macro does not attempt to take advantage of '[[maybe_unused]]'.
#if ABSL_HAVE_ATTRIBUTE(unused) || (defined(__GNUC__) && !defined(__clang__))
#undef ABSL_ATTRIBUTE_UNUSED
#define ABSL_ATTRIBUTE_UNUSED __attribute__((__unused__))
#else
#define ABSL_ATTRIBUTE_UNUSED
#endif
// ABSL_ATTRIBUTE_INITIAL_EXEC
//
// Tells the compiler to use "initial-exec" mode for a thread-local variable.
// See http://people.redhat.com/drepper/tls.pdf for the gory details.
#if ABSL_HAVE_ATTRIBUTE(tls_model) || (defined(__GNUC__) && !defined(__clang__))
#define ABSL_ATTRIBUTE_INITIAL_EXEC __attribute__((tls_model("initial-exec")))
#else
#define ABSL_ATTRIBUTE_INITIAL_EXEC
#endif
// ABSL_ATTRIBUTE_PACKED
//
// Instructs the compiler not to use natural alignment for a tagged data
// structure, but instead to reduce its alignment to 1.
//
// Therefore, DO NOT APPLY THIS ATTRIBUTE TO STRUCTS CONTAINING ATOMICS. Doing
// so can cause atomic variables to be mis-aligned and silently violate
// atomicity on x86.
//
// This attribute can either be applied to members of a structure or to a
// structure in its entirety. Applying this attribute (judiciously) to a
// structure in its entirety to optimize the memory footprint of very
// commonly-used structs is fine. Do not apply this attribute to a structure in
// its entirety if the purpose is to control the offsets of the members in the
// structure. Instead, apply this attribute only to structure members that need
// it.
//
// When applying ABSL_ATTRIBUTE_PACKED only to specific structure members the
// natural alignment of structure members not annotated is preserved. Aligned
// member accesses are faster than non-aligned member accesses even if the
// targeted microprocessor supports non-aligned accesses.
#if ABSL_HAVE_ATTRIBUTE(packed) || (defined(__GNUC__) && !defined(__clang__))
#define ABSL_ATTRIBUTE_PACKED __attribute__((__packed__))
#else
#define ABSL_ATTRIBUTE_PACKED
#endif
// ABSL_ATTRIBUTE_FUNC_ALIGN
//
// Tells the compiler to align the function start at least to certain
// alignment boundary
#if ABSL_HAVE_ATTRIBUTE(aligned) || (defined(__GNUC__) && !defined(__clang__))
#define ABSL_ATTRIBUTE_FUNC_ALIGN(bytes) __attribute__((aligned(bytes)))
#else
#define ABSL_ATTRIBUTE_FUNC_ALIGN(bytes)
#endif
// ABSL_FALLTHROUGH_INTENDED
//
// Annotates implicit fall-through between switch labels, allowing a case to
// indicate intentional fallthrough and turn off warnings about any lack of a
// `break` statement. The ABSL_FALLTHROUGH_INTENDED macro should be followed by
// a semicolon and can be used in most places where `break` can, provided that
// no statements exist between it and the next switch label.
//
// Example:
//
// switch (x) {
// case 40:
// case 41:
// if (truth_is_out_there) {
// ++x;
// ABSL_FALLTHROUGH_INTENDED; // Use instead of/along with annotations
// // in comments
// } else {
// return x;
// }
// case 42:
// ...
//
// Notes: When supported, GCC and Clang can issue a warning on switch labels
// with unannotated fallthrough using the warning `-Wimplicit-fallthrough`. See
// clang documentation on language extensions for details:
// https://clang.llvm.org/docs/AttributeReference.html#fallthrough-clang-fallthrough
//
// When used with unsupported compilers, the ABSL_FALLTHROUGH_INTENDED macro has
// no effect on diagnostics. In any case this macro has no effect on runtime
// behavior and performance of code.
#ifdef ABSL_FALLTHROUGH_INTENDED
#error "ABSL_FALLTHROUGH_INTENDED should not be defined."
#elif ABSL_HAVE_CPP_ATTRIBUTE(fallthrough)
#define ABSL_FALLTHROUGH_INTENDED [[fallthrough]]
#elif ABSL_HAVE_CPP_ATTRIBUTE(clang::fallthrough)
#define ABSL_FALLTHROUGH_INTENDED [[clang::fallthrough]]
#elif ABSL_HAVE_CPP_ATTRIBUTE(gnu::fallthrough)
#define ABSL_FALLTHROUGH_INTENDED [[gnu::fallthrough]]
#else
#define ABSL_FALLTHROUGH_INTENDED \
do { \
} while (0)
#endif
// ABSL_DEPRECATED()
//
// Marks a deprecated class, struct, enum, function, method and variable
// declarations. The macro argument is used as a custom diagnostic message (e.g.
// suggestion of a better alternative).
//
// For code or headers that are assured to only build with C++14 and up, prefer
// just using the standard `[[deprecated("message")]]` directly over this macro.
//
// Examples:
//
// class ABSL_DEPRECATED("Use Bar instead") Foo {...};
//
// ABSL_DEPRECATED("Use Baz() instead") void Bar() {...}
//
// template <typename T>
// ABSL_DEPRECATED("Use DoThat() instead")
// void DoThis();
//
// enum FooEnum {
// kBar ABSL_DEPRECATED("Use kBaz instead"),
// };
//
// Every usage of a deprecated entity will trigger a warning when compiled with
// GCC/Clang's `-Wdeprecated-declarations` option. Google's production toolchain
// turns this warning off by default, instead relying on clang-tidy to report
// new uses of deprecated code.
#if ABSL_HAVE_ATTRIBUTE(deprecated)
#define ABSL_DEPRECATED(message) __attribute__((deprecated(message)))
#else
#define ABSL_DEPRECATED(message)
#endif
// When deprecating Abseil code, it is sometimes necessary to turn off the
// warning within Abseil, until the deprecated code is actually removed. The
// deprecated code can be surrounded with these directives to achieve that
// result.
//
// class ABSL_DEPRECATED("Use Bar instead") Foo;
//
// ABSL_INTERNAL_DISABLE_DEPRECATED_DECLARATION_WARNING
// Baz ComputeBazFromFoo(Foo f);
// ABSL_INTERNAL_RESTORE_DEPRECATED_DECLARATION_WARNING
#if defined(__GNUC__) || defined(__clang__)
// Clang also supports these GCC pragmas.
#define ABSL_INTERNAL_DISABLE_DEPRECATED_DECLARATION_WARNING \
_Pragma("GCC diagnostic push") \
_Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
#define ABSL_INTERNAL_RESTORE_DEPRECATED_DECLARATION_WARNING \
_Pragma("GCC diagnostic pop")
#else
#define ABSL_INTERNAL_DISABLE_DEPRECATED_DECLARATION_WARNING
#define ABSL_INTERNAL_RESTORE_DEPRECATED_DECLARATION_WARNING
#endif // defined(__GNUC__) || defined(__clang__)
// ABSL_CONST_INIT
//
// A variable declaration annotated with the `ABSL_CONST_INIT` attribute will
// not compile (on supported platforms) unless the variable has a constant
// initializer. This is useful for variables with static and thread storage
// duration, because it guarantees that they will not suffer from the so-called
// "static init order fiasco".
//
// This attribute must be placed on the initializing declaration of the
// variable. Some compilers will give a -Wmissing-constinit warning when this
// attribute is placed on some other declaration but missing from the
// initializing declaration.
//
// In some cases (notably with thread_local variables), `ABSL_CONST_INIT` can
// also be used in a non-initializing declaration to tell the compiler that a
// variable is already initialized, reducing overhead that would otherwise be
// incurred by a hidden guard variable. Thus annotating all declarations with
// this attribute is recommended to potentially enhance optimization.
//
// Example:
//
// class MyClass {
// public:
// ABSL_CONST_INIT static MyType my_var;
// };
//
// ABSL_CONST_INIT MyType MyClass::my_var = MakeMyType(...);
//
// For code or headers that are assured to only build with C++20 and up, prefer
// just using the standard `constinit` keyword directly over this macro.
//
// Note that this attribute is redundant if the variable is declared constexpr.
#if defined(__cpp_constinit) && __cpp_constinit >= 201907L
#define ABSL_CONST_INIT constinit
#elif ABSL_HAVE_CPP_ATTRIBUTE(clang::require_constant_initialization)
#define ABSL_CONST_INIT [[clang::require_constant_initialization]]
#else
#define ABSL_CONST_INIT
#endif
// ABSL_ATTRIBUTE_PURE_FUNCTION
//
// ABSL_ATTRIBUTE_PURE_FUNCTION is used to annotate declarations of "pure"
// functions. A function is pure if its return value is only a function of its
// arguments. The pure attribute prohibits a function from modifying the state
// of the program that is observable by means other than inspecting the
// function's return value. Declaring such functions with the pure attribute
// allows the compiler to avoid emitting some calls in repeated invocations of
// the function with the same argument values.
//
// Example:
//
// ABSL_ATTRIBUTE_PURE_FUNCTION std::string FormatTime(Time t);
#if ABSL_HAVE_CPP_ATTRIBUTE(gnu::pure)
#define ABSL_ATTRIBUTE_PURE_FUNCTION [[gnu::pure]]
#elif ABSL_HAVE_ATTRIBUTE(pure)
#define ABSL_ATTRIBUTE_PURE_FUNCTION __attribute__((pure))
#else
// If the attribute isn't defined, we'll fallback to ABSL_MUST_USE_RESULT since
// pure functions are useless if its return is ignored.
#define ABSL_ATTRIBUTE_PURE_FUNCTION ABSL_MUST_USE_RESULT
#endif
// ABSL_ATTRIBUTE_CONST_FUNCTION
//
// ABSL_ATTRIBUTE_CONST_FUNCTION is used to annotate declarations of "const"
// functions. A const function is similar to a pure function, with one
// exception: Pure functions may return value that depend on a non-volatile
// object that isn't provided as a function argument, while the const function
// is guaranteed to return the same result given the same arguments.
//
// Example:
//
// ABSL_ATTRIBUTE_CONST_FUNCTION int64_t ToInt64Milliseconds(Duration d);
#if defined(_MSC_VER) && !defined(__clang__)
// Put the MSVC case first since MSVC seems to parse const as a C++ keyword.
#define ABSL_ATTRIBUTE_CONST_FUNCTION ABSL_ATTRIBUTE_PURE_FUNCTION
#elif ABSL_HAVE_CPP_ATTRIBUTE(gnu::const)
#define ABSL_ATTRIBUTE_CONST_FUNCTION [[gnu::const]]
#elif ABSL_HAVE_ATTRIBUTE(const)
#define ABSL_ATTRIBUTE_CONST_FUNCTION __attribute__((const))
#else
// Since const functions are more restrictive pure function, we'll fallback to a
// pure function if the const attribute is not handled.
#define ABSL_ATTRIBUTE_CONST_FUNCTION ABSL_ATTRIBUTE_PURE_FUNCTION
#endif
// ABSL_ATTRIBUTE_LIFETIME_BOUND indicates that a resource owned by a function
// parameter or implicit object parameter is retained by the return value of the
// annotated function (or, for a parameter of a constructor, in the value of the
// constructed object). This attribute causes warnings to be produced if a
// temporary object does not live long enough.
//
// When applied to a reference parameter, the referenced object is assumed to be
// retained by the return value of the function. When applied to a non-reference
// parameter (for example, a pointer or a class type), all temporaries
// referenced by the parameter are assumed to be retained by the return value of
// the function.
//
// See also the upstream documentation:
// https://clang.llvm.org/docs/AttributeReference.html#lifetimebound
#if ABSL_HAVE_CPP_ATTRIBUTE(clang::lifetimebound)
#define ABSL_ATTRIBUTE_LIFETIME_BOUND [[clang::lifetimebound]]
#elif ABSL_HAVE_ATTRIBUTE(lifetimebound)
#define ABSL_ATTRIBUTE_LIFETIME_BOUND __attribute__((lifetimebound))
#else
#define ABSL_ATTRIBUTE_LIFETIME_BOUND
#endif
// ABSL_ATTRIBUTE_TRIVIAL_ABI
// Indicates that a type is "trivially relocatable" -- meaning it can be
// relocated without invoking the constructor/destructor, using a form of move
// elision.
//
// From a memory safety point of view, putting aside destructor ordering, it's
// safe to apply ABSL_ATTRIBUTE_TRIVIAL_ABI if an object's location
// can change over the course of its lifetime: if a constructor can be run one
// place, and then the object magically teleports to another place where some
// methods are run, and then the object teleports to yet another place where it
// is destroyed. This is notably not true for self-referential types, where the
// move-constructor must keep the self-reference up to date. If the type changed
// location without invoking the move constructor, it would have a dangling
// self-reference.
//
// The use of this teleporting machinery means that the number of paired
// move/destroy operations can change, and so it is a bad idea to apply this to
// a type meant to count the number of moves.
//
// Warning: applying this can, rarely, break callers. Objects passed by value
// will be destroyed at the end of the call, instead of the end of the
// full-expression containing the call. In addition, it changes the ABI
// of functions accepting this type by value (e.g. to pass in registers).
//
// See also the upstream documentation:
// https://clang.llvm.org/docs/AttributeReference.html#trivial-abi
//
#if ABSL_HAVE_CPP_ATTRIBUTE(clang::trivial_abi)
#define ABSL_ATTRIBUTE_TRIVIAL_ABI [[clang::trivial_abi]]
#define ABSL_HAVE_ATTRIBUTE_TRIVIAL_ABI 1
#elif ABSL_HAVE_ATTRIBUTE(trivial_abi)
#define ABSL_ATTRIBUTE_TRIVIAL_ABI __attribute__((trivial_abi))
#define ABSL_HAVE_ATTRIBUTE_TRIVIAL_ABI 1
#else
#define ABSL_ATTRIBUTE_TRIVIAL_ABI
#endif
// ABSL_ATTRIBUTE_NO_UNIQUE_ADDRESS
//
// Indicates a data member can be optimized to occupy no space (if it is empty)
// and/or its tail padding can be used for other members.
//
// For code that is assured to only build with C++20 or later, prefer using
// the standard attribute `[[no_unique_address]]` directly instead of this
// macro.
//
// https://devblogs.microsoft.com/cppblog/msvc-cpp20-and-the-std-cpp20-switch/#c20-no_unique_address
// Current versions of MSVC have disabled `[[no_unique_address]]` since it
// breaks ABI compatibility, but offers `[[msvc::no_unique_address]]` for
// situations when it can be assured that it is desired. Since Abseil does not
// claim ABI compatibility in mixed builds, we can offer it unconditionally.
#if defined(_MSC_VER) && _MSC_VER >= 1929
#define ABSL_ATTRIBUTE_NO_UNIQUE_ADDRESS [[msvc::no_unique_address]]
#elif ABSL_HAVE_CPP_ATTRIBUTE(no_unique_address)
#define ABSL_ATTRIBUTE_NO_UNIQUE_ADDRESS [[no_unique_address]]
#else
#define ABSL_ATTRIBUTE_NO_UNIQUE_ADDRESS
#endif
#endif // ABSL_BASE_ATTRIBUTES_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: call_once.h
// -----------------------------------------------------------------------------
//
// This header file provides an Abseil version of `std::call_once` for invoking
// a given function at most once, across all threads. This Abseil version is
// faster than the C++11 version and incorporates the C++17 argument-passing
// fix, so that (for example) non-const references may be passed to the invoked
// function.
#ifndef ABSL_BASE_CALL_ONCE_H_
#define ABSL_BASE_CALL_ONCE_H_
#include <algorithm>
#include <atomic>
#include <cstdint>
#include <type_traits>
#include <utility>
#include "absl/base/internal/invoke.h"
#include "absl/base/internal/low_level_scheduling.h"
#include "absl/base/internal/raw_logging.h"
#include "absl/base/internal/scheduling_mode.h"
#include "absl/base/internal/spinlock_wait.h"
#include "absl/base/macros.h"
#include "absl/base/optimization.h"
#include "absl/base/port.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
class once_flag;
namespace base_internal {
std::atomic<uint32_t>* ControlWord(absl::once_flag* flag);
} // namespace base_internal
// call_once()
//
// For all invocations using a given `once_flag`, invokes a given `fn` exactly
// once across all threads. The first call to `call_once()` with a particular
// `once_flag` argument (that does not throw an exception) will run the
// specified function with the provided `args`; other calls with the same
// `once_flag` argument will not run the function, but will wait
// for the provided function to finish running (if it is still running).
//
// This mechanism provides a safe, simple, and fast mechanism for one-time
// initialization in a multi-threaded process.
//
// Example:
//
// class MyInitClass {
// public:
// ...
// mutable absl::once_flag once_;
//
// MyInitClass* init() const {
// absl::call_once(once_, &MyInitClass::Init, this);
// return ptr_;
// }
//
template <typename Callable, typename... Args>
void call_once(absl::once_flag& flag, Callable&& fn, Args&&... args);
// once_flag
//
// Objects of this type are used to distinguish calls to `call_once()` and
// ensure the provided function is only invoked once across all threads. This
// type is not copyable or movable. However, it has a `constexpr`
// constructor, and is safe to use as a namespace-scoped global variable.
class once_flag {
public:
constexpr once_flag() : control_(0) {}
once_flag(const once_flag&) = delete;
once_flag& operator=(const once_flag&) = delete;
private:
friend std::atomic<uint32_t>* base_internal::ControlWord(once_flag* flag);
std::atomic<uint32_t> control_;
};
//------------------------------------------------------------------------------
// End of public interfaces.
// Implementation details follow.
//------------------------------------------------------------------------------
namespace base_internal {
// Like call_once, but uses KERNEL_ONLY scheduling. Intended to be used to
// initialize entities used by the scheduler implementation.
template <typename Callable, typename... Args>
void LowLevelCallOnce(absl::once_flag* flag, Callable&& fn, Args&&... args);
// Disables scheduling while on stack when scheduling mode is non-cooperative.
// No effect for cooperative scheduling modes.
class SchedulingHelper {
public:
explicit SchedulingHelper(base_internal::SchedulingMode mode) : mode_(mode) {
if (mode_ == base_internal::SCHEDULE_KERNEL_ONLY) {
guard_result_ = base_internal::SchedulingGuard::DisableRescheduling();
}
}
~SchedulingHelper() {
if (mode_ == base_internal::SCHEDULE_KERNEL_ONLY) {
base_internal::SchedulingGuard::EnableRescheduling(guard_result_);
}
}
private:
base_internal::SchedulingMode mode_;
bool guard_result_ = false;
};
// Bit patterns for call_once state machine values. Internal implementation
// detail, not for use by clients.
//
// The bit patterns are arbitrarily chosen from unlikely values, to aid in
// debugging. However, kOnceInit must be 0, so that a zero-initialized
// once_flag will be valid for immediate use.
enum {
kOnceInit = 0,
kOnceRunning = 0x65C2937B,
kOnceWaiter = 0x05A308D2,
// A very small constant is chosen for kOnceDone so that it fit in a single
// compare with immediate instruction for most common ISAs. This is verified
// for x86, POWER and ARM.
kOnceDone = 221, // Random Number
};
template <typename Callable, typename... Args>
ABSL_ATTRIBUTE_NOINLINE
void CallOnceImpl(std::atomic<uint32_t>* control,
base_internal::SchedulingMode scheduling_mode, Callable&& fn,
Args&&... args) {
#ifndef NDEBUG
{
uint32_t old_control = control->load(std::memory_order_relaxed);
if (old_control != kOnceInit &&
old_control != kOnceRunning &&
old_control != kOnceWaiter &&
old_control != kOnceDone) {
ABSL_RAW_LOG(FATAL, "Unexpected value for control word: 0x%lx",
static_cast<unsigned long>(old_control)); // NOLINT
}
}
#endif // NDEBUG
static const base_internal::SpinLockWaitTransition trans[] = {
{kOnceInit, kOnceRunning, true},
{kOnceRunning, kOnceWaiter, false},
{kOnceDone, kOnceDone, true}};
// Must do this before potentially modifying control word's state.
base_internal::SchedulingHelper maybe_disable_scheduling(scheduling_mode);
// Short circuit the simplest case to avoid procedure call overhead.
// The base_internal::SpinLockWait() call returns either kOnceInit or
// kOnceDone. If it returns kOnceDone, it must have loaded the control word
// with std::memory_order_acquire and seen a value of kOnceDone.
uint32_t old_control = kOnceInit;
if (control->compare_exchange_strong(old_control, kOnceRunning,
std::memory_order_relaxed) ||
base_internal::SpinLockWait(control, ABSL_ARRAYSIZE(trans), trans,
scheduling_mode) == kOnceInit) {
base_internal::invoke(std::forward<Callable>(fn),
std::forward<Args>(args)...);
old_control =
control->exchange(base_internal::kOnceDone, std::memory_order_release);
if (old_control == base_internal::kOnceWaiter) {
base_internal::SpinLockWake(control, true);
}
} // else *control is already kOnceDone
}
inline std::atomic<uint32_t>* ControlWord(once_flag* flag) {
return &flag->control_;
}
template <typename Callable, typename... Args>
void LowLevelCallOnce(absl::once_flag* flag, Callable&& fn, Args&&... args) {
std::atomic<uint32_t>* once = base_internal::ControlWord(flag);
uint32_t s = once->load(std::memory_order_acquire);
if (ABSL_PREDICT_FALSE(s != base_internal::kOnceDone)) {
base_internal::CallOnceImpl(once, base_internal::SCHEDULE_KERNEL_ONLY,
std::forward<Callable>(fn),
std::forward<Args>(args)...);
}
}
} // namespace base_internal
template <typename Callable, typename... Args>
void call_once(absl::once_flag& flag, Callable&& fn, Args&&... args) {
std::atomic<uint32_t>* once = base_internal::ControlWord(&flag);
uint32_t s = once->load(std::memory_order_acquire);
if (ABSL_PREDICT_FALSE(s != base_internal::kOnceDone)) {
base_internal::CallOnceImpl(
once, base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL,
std::forward<Callable>(fn), std::forward<Args>(args)...);
}
}
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_CALL_ONCE_H_

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//
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: casts.h
// -----------------------------------------------------------------------------
//
// This header file defines casting templates to fit use cases not covered by
// the standard casts provided in the C++ standard. As with all cast operations,
// use these with caution and only if alternatives do not exist.
#ifndef ABSL_BASE_CASTS_H_
#define ABSL_BASE_CASTS_H_
#include <cstring>
#include <memory>
#include <type_traits>
#include <utility>
#if defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L
#include <bit> // For std::bit_cast.
#endif // defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L
#include "absl/base/internal/identity.h"
#include "absl/base/macros.h"
#include "absl/meta/type_traits.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
// implicit_cast()
//
// Performs an implicit conversion between types following the language
// rules for implicit conversion; if an implicit conversion is otherwise
// allowed by the language in the given context, this function performs such an
// implicit conversion.
//
// Example:
//
// // If the context allows implicit conversion:
// From from;
// To to = from;
//
// // Such code can be replaced by:
// implicit_cast<To>(from);
//
// An `implicit_cast()` may also be used to annotate numeric type conversions
// that, although safe, may produce compiler warnings (such as `long` to `int`).
// Additionally, an `implicit_cast()` is also useful within return statements to
// indicate a specific implicit conversion is being undertaken.
//
// Example:
//
// return implicit_cast<double>(size_in_bytes) / capacity_;
//
// Annotating code with `implicit_cast()` allows you to explicitly select
// particular overloads and template instantiations, while providing a safer
// cast than `reinterpret_cast()` or `static_cast()`.
//
// Additionally, an `implicit_cast()` can be used to allow upcasting within a
// type hierarchy where incorrect use of `static_cast()` could accidentally
// allow downcasting.
//
// Finally, an `implicit_cast()` can be used to perform implicit conversions
// from unrelated types that otherwise couldn't be implicitly cast directly;
// C++ will normally only implicitly cast "one step" in such conversions.
//
// That is, if C is a type which can be implicitly converted to B, with B being
// a type that can be implicitly converted to A, an `implicit_cast()` can be
// used to convert C to B (which the compiler can then implicitly convert to A
// using language rules).
//
// Example:
//
// // Assume an object C is convertible to B, which is implicitly convertible
// // to A
// A a = implicit_cast<B>(C);
//
// Such implicit cast chaining may be useful within template logic.
template <typename To>
constexpr To implicit_cast(typename absl::internal::identity_t<To> to) {
return to;
}
// bit_cast()
//
// Creates a value of the new type `Dest` whose representation is the same as
// that of the argument, which is of (deduced) type `Source` (a "bitwise cast";
// every bit in the value representation of the result is equal to the
// corresponding bit in the object representation of the source). Source and
// destination types must be of the same size, and both types must be trivially
// copyable.
//
// As with most casts, use with caution. A `bit_cast()` might be needed when you
// need to treat a value as the value of some other type, for example, to access
// the individual bits of an object which are not normally accessible through
// the object's type, such as for working with the binary representation of a
// floating point value:
//
// float f = 3.14159265358979;
// int i = bit_cast<int>(f);
// // i = 0x40490fdb
//
// Reinterpreting and accessing a value directly as a different type (as shown
// below) usually results in undefined behavior.
//
// Example:
//
// // WRONG
// float f = 3.14159265358979;
// int i = reinterpret_cast<int&>(f); // Wrong
// int j = *reinterpret_cast<int*>(&f); // Equally wrong
// int k = *bit_cast<int*>(&f); // Equally wrong
//
// Reinterpret-casting results in undefined behavior according to the ISO C++
// specification, section [basic.lval]. Roughly, this section says: if an object
// in memory has one type, and a program accesses it with a different type, the
// result is undefined behavior for most "different type".
//
// Using bit_cast on a pointer and then dereferencing it is no better than using
// reinterpret_cast. You should only use bit_cast on the value itself.
//
// Such casting results in type punning: holding an object in memory of one type
// and reading its bits back using a different type. A `bit_cast()` avoids this
// issue by copying the object representation to a new value, which avoids
// introducing this undefined behavior (since the original value is never
// accessed in the wrong way).
//
// The requirements of `absl::bit_cast` are more strict than that of
// `std::bit_cast` unless compiler support is available. Specifically, without
// compiler support, this implementation also requires `Dest` to be
// default-constructible. In C++20, `absl::bit_cast` is replaced by
// `std::bit_cast`.
#if defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L
using std::bit_cast;
#else // defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L
template <
typename Dest, typename Source,
typename std::enable_if<sizeof(Dest) == sizeof(Source) &&
std::is_trivially_copyable<Source>::value &&
std::is_trivially_copyable<Dest>::value
#if !ABSL_HAVE_BUILTIN(__builtin_bit_cast)
&& std::is_default_constructible<Dest>::value
#endif // !ABSL_HAVE_BUILTIN(__builtin_bit_cast)
,
int>::type = 0>
#if ABSL_HAVE_BUILTIN(__builtin_bit_cast)
inline constexpr Dest bit_cast(const Source& source) {
return __builtin_bit_cast(Dest, source);
}
#else // ABSL_HAVE_BUILTIN(__builtin_bit_cast)
inline Dest bit_cast(const Source& source) {
Dest dest;
memcpy(static_cast<void*>(std::addressof(dest)),
static_cast<const void*>(std::addressof(source)), sizeof(dest));
return dest;
}
#endif // ABSL_HAVE_BUILTIN(__builtin_bit_cast)
#endif // defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_CASTS_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// kConstInit
// -----------------------------------------------------------------------------
//
// A constructor tag used to mark an object as safe for use as a global
// variable, avoiding the usual lifetime issues that can affect globals.
#ifndef ABSL_BASE_CONST_INIT_H_
#define ABSL_BASE_CONST_INIT_H_
#include "absl/base/config.h"
// In general, objects with static storage duration (such as global variables)
// can trigger tricky object lifetime situations. Attempting to access them
// from the constructors or destructors of other global objects can result in
// undefined behavior, unless their constructors and destructors are designed
// with this issue in mind.
//
// The normal way to deal with this issue in C++11 is to use constant
// initialization and trivial destructors.
//
// Constant initialization is guaranteed to occur before any other code
// executes. Constructors that are declared 'constexpr' are eligible for
// constant initialization. You can annotate a variable declaration with the
// ABSL_CONST_INIT macro to express this intent. For compilers that support
// it, this annotation will cause a compilation error for declarations that
// aren't subject to constant initialization (perhaps because a runtime value
// was passed as a constructor argument).
//
// On program shutdown, lifetime issues can be avoided on global objects by
// ensuring that they contain trivial destructors. A class has a trivial
// destructor unless it has a user-defined destructor, a virtual method or base
// class, or a data member or base class with a non-trivial destructor of its
// own. Objects with static storage duration and a trivial destructor are not
// cleaned up on program shutdown, and are thus safe to access from other code
// running during shutdown.
//
// For a few core Abseil classes, we make a best effort to allow for safe global
// instances, even though these classes have non-trivial destructors. These
// objects can be created with the absl::kConstInit tag. For example:
// ABSL_CONST_INIT absl::Mutex global_mutex(absl::kConstInit);
//
// The line above declares a global variable of type absl::Mutex which can be
// accessed at any point during startup or shutdown. global_mutex's destructor
// will still run, but will not invalidate the object. Note that C++ specifies
// that accessing an object after its destructor has run results in undefined
// behavior, but this pattern works on the toolchains we support.
//
// The absl::kConstInit tag should only be used to define objects with static
// or thread_local storage duration.
namespace absl {
ABSL_NAMESPACE_BEGIN
enum ConstInitType {
kConstInit,
};
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_CONST_INIT_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// This file defines dynamic annotations for use with dynamic analysis tool
// such as valgrind, PIN, etc.
//
// Dynamic annotation is a source code annotation that affects the generated
// code (that is, the annotation is not a comment). Each such annotation is
// attached to a particular instruction and/or to a particular object (address)
// in the program.
//
// The annotations that should be used by users are macros in all upper-case
// (e.g., ABSL_ANNOTATE_THREAD_NAME).
//
// Actual implementation of these macros may differ depending on the dynamic
// analysis tool being used.
//
// This file supports the following configurations:
// - Dynamic Annotations enabled (with static thread-safety warnings disabled).
// In this case, macros expand to functions implemented by Thread Sanitizer,
// when building with TSan. When not provided an external implementation,
// dynamic_annotations.cc provides no-op implementations.
//
// - Static Clang thread-safety warnings enabled.
// When building with a Clang compiler that supports thread-safety warnings,
// a subset of annotations can be statically-checked at compile-time. We
// expand these macros to static-inline functions that can be analyzed for
// thread-safety, but afterwards elided when building the final binary.
//
// - All annotations are disabled.
// If neither Dynamic Annotations nor Clang thread-safety warnings are
// enabled, then all annotation-macros expand to empty.
#ifndef ABSL_BASE_DYNAMIC_ANNOTATIONS_H_
#define ABSL_BASE_DYNAMIC_ANNOTATIONS_H_
#include <stddef.h>
#include <stdint.h>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#ifdef __cplusplus
#include "absl/base/macros.h"
#endif
#ifdef ABSL_HAVE_HWADDRESS_SANITIZER
#include <sanitizer/hwasan_interface.h>
#endif
// TODO(rogeeff): Remove after the backward compatibility period.
#include "absl/base/internal/dynamic_annotations.h" // IWYU pragma: export
// -------------------------------------------------------------------------
// Decide which features are enabled.
#ifdef ABSL_HAVE_THREAD_SANITIZER
#define ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED 1
#define ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED 1
#define ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED 1
#define ABSL_INTERNAL_ANNOTALYSIS_ENABLED 0
#define ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED 1
#else
#define ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED 0
#define ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED 0
#define ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED 0
// Clang provides limited support for static thread-safety analysis through a
// feature called Annotalysis. We configure macro-definitions according to
// whether Annotalysis support is available. When running in opt-mode, GCC
// will issue a warning, if these attributes are compiled. Only include them
// when compiling using Clang.
#if defined(__clang__)
#define ABSL_INTERNAL_ANNOTALYSIS_ENABLED 1
#if !defined(SWIG)
#define ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED 1
#endif
#else
#define ABSL_INTERNAL_ANNOTALYSIS_ENABLED 0
#endif
// Read/write annotations are enabled in Annotalysis mode; disabled otherwise.
#define ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED \
ABSL_INTERNAL_ANNOTALYSIS_ENABLED
#endif // ABSL_HAVE_THREAD_SANITIZER
#ifdef __cplusplus
#define ABSL_INTERNAL_BEGIN_EXTERN_C extern "C" {
#define ABSL_INTERNAL_END_EXTERN_C } // extern "C"
#define ABSL_INTERNAL_GLOBAL_SCOPED(F) ::F
#define ABSL_INTERNAL_STATIC_INLINE inline
#else
#define ABSL_INTERNAL_BEGIN_EXTERN_C // empty
#define ABSL_INTERNAL_END_EXTERN_C // empty
#define ABSL_INTERNAL_GLOBAL_SCOPED(F) F
#define ABSL_INTERNAL_STATIC_INLINE static inline
#endif
// -------------------------------------------------------------------------
// Define race annotations.
#if ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED == 1
// Some of the symbols used in this section (e.g. AnnotateBenignRaceSized) are
// defined by the compiler-based sanitizer implementation, not by the Abseil
// library. Therefore they do not use ABSL_INTERNAL_C_SYMBOL.
// -------------------------------------------------------------
// Annotations that suppress errors. It is usually better to express the
// program's synchronization using the other annotations, but these can be used
// when all else fails.
// Report that we may have a benign race at `pointer`, with size
// "sizeof(*(pointer))". `pointer` must be a non-void* pointer. Insert at the
// point where `pointer` has been allocated, preferably close to the point
// where the race happens. See also ABSL_ANNOTATE_BENIGN_RACE_STATIC.
#define ABSL_ANNOTATE_BENIGN_RACE(pointer, description) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateBenignRaceSized) \
(__FILE__, __LINE__, pointer, sizeof(*(pointer)), description)
// Same as ABSL_ANNOTATE_BENIGN_RACE(`address`, `description`), but applies to
// the memory range [`address`, `address`+`size`).
#define ABSL_ANNOTATE_BENIGN_RACE_SIZED(address, size, description) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateBenignRaceSized) \
(__FILE__, __LINE__, address, size, description)
// Enable (`enable`!=0) or disable (`enable`==0) race detection for all threads.
// This annotation could be useful if you want to skip expensive race analysis
// during some period of program execution, e.g. during initialization.
#define ABSL_ANNOTATE_ENABLE_RACE_DETECTION(enable) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateEnableRaceDetection) \
(__FILE__, __LINE__, enable)
// -------------------------------------------------------------
// Annotations useful for debugging.
// Report the current thread `name` to a race detector.
#define ABSL_ANNOTATE_THREAD_NAME(name) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateThreadName)(__FILE__, __LINE__, name)
// -------------------------------------------------------------
// Annotations useful when implementing locks. They are not normally needed by
// modules that merely use locks. The `lock` argument is a pointer to the lock
// object.
// Report that a lock has been created at address `lock`.
#define ABSL_ANNOTATE_RWLOCK_CREATE(lock) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockCreate)(__FILE__, __LINE__, lock)
// Report that a linker initialized lock has been created at address `lock`.
#ifdef ABSL_HAVE_THREAD_SANITIZER
#define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockCreateStatic) \
(__FILE__, __LINE__, lock)
#else
#define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) \
ABSL_ANNOTATE_RWLOCK_CREATE(lock)
#endif
// Report that the lock at address `lock` is about to be destroyed.
#define ABSL_ANNOTATE_RWLOCK_DESTROY(lock) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockDestroy)(__FILE__, __LINE__, lock)
// Report that the lock at address `lock` has been acquired.
// `is_w`=1 for writer lock, `is_w`=0 for reader lock.
#define ABSL_ANNOTATE_RWLOCK_ACQUIRED(lock, is_w) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockAcquired) \
(__FILE__, __LINE__, lock, is_w)
// Report that the lock at address `lock` is about to be released.
// `is_w`=1 for writer lock, `is_w`=0 for reader lock.
#define ABSL_ANNOTATE_RWLOCK_RELEASED(lock, is_w) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockReleased) \
(__FILE__, __LINE__, lock, is_w)
// Apply ABSL_ANNOTATE_BENIGN_RACE_SIZED to a static variable `static_var`.
#define ABSL_ANNOTATE_BENIGN_RACE_STATIC(static_var, description) \
namespace { \
class static_var##_annotator { \
public: \
static_var##_annotator() { \
ABSL_ANNOTATE_BENIGN_RACE_SIZED(&static_var, sizeof(static_var), \
#static_var ": " description); \
} \
}; \
static static_var##_annotator the##static_var##_annotator; \
} // namespace
// Function prototypes of annotations provided by the compiler-based sanitizer
// implementation.
ABSL_INTERNAL_BEGIN_EXTERN_C
void AnnotateRWLockCreate(const char* file, int line,
const volatile void* lock);
void AnnotateRWLockCreateStatic(const char* file, int line,
const volatile void* lock);
void AnnotateRWLockDestroy(const char* file, int line,
const volatile void* lock);
void AnnotateRWLockAcquired(const char* file, int line,
const volatile void* lock, long is_w); // NOLINT
void AnnotateRWLockReleased(const char* file, int line,
const volatile void* lock, long is_w); // NOLINT
void AnnotateBenignRace(const char* file, int line,
const volatile void* address, const char* description);
void AnnotateBenignRaceSized(const char* file, int line,
const volatile void* address, size_t size,
const char* description);
void AnnotateThreadName(const char* file, int line, const char* name);
void AnnotateEnableRaceDetection(const char* file, int line, int enable);
ABSL_INTERNAL_END_EXTERN_C
#else // ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED == 0
#define ABSL_ANNOTATE_RWLOCK_CREATE(lock) // empty
#define ABSL_ANNOTATE_RWLOCK_CREATE_STATIC(lock) // empty
#define ABSL_ANNOTATE_RWLOCK_DESTROY(lock) // empty
#define ABSL_ANNOTATE_RWLOCK_ACQUIRED(lock, is_w) // empty
#define ABSL_ANNOTATE_RWLOCK_RELEASED(lock, is_w) // empty
#define ABSL_ANNOTATE_BENIGN_RACE(address, description) // empty
#define ABSL_ANNOTATE_BENIGN_RACE_SIZED(address, size, description) // empty
#define ABSL_ANNOTATE_THREAD_NAME(name) // empty
#define ABSL_ANNOTATE_ENABLE_RACE_DETECTION(enable) // empty
#define ABSL_ANNOTATE_BENIGN_RACE_STATIC(static_var, description) // empty
#endif // ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED
// -------------------------------------------------------------------------
// Define memory annotations.
#ifdef ABSL_HAVE_MEMORY_SANITIZER
#include <sanitizer/msan_interface.h>
#define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) \
__msan_unpoison(address, size)
#define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) \
__msan_allocated_memory(address, size)
#else // !defined(ABSL_HAVE_MEMORY_SANITIZER)
// TODO(rogeeff): remove this branch
#ifdef ABSL_HAVE_THREAD_SANITIZER
#define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) \
do { \
(void)(address); \
(void)(size); \
} while (0)
#define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) \
do { \
(void)(address); \
(void)(size); \
} while (0)
#else
#define ABSL_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) // empty
#define ABSL_ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) // empty
#endif
#endif // ABSL_HAVE_MEMORY_SANITIZER
// -------------------------------------------------------------------------
// Define IGNORE_READS_BEGIN/_END attributes.
#if defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
#define ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE \
__attribute((exclusive_lock_function("*")))
#define ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE \
__attribute((unlock_function("*")))
#else // !defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
#define ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE // empty
#define ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE // empty
#endif // defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
// -------------------------------------------------------------------------
// Define IGNORE_READS_BEGIN/_END annotations.
#if ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED == 1
// Some of the symbols used in this section (e.g. AnnotateIgnoreReadsBegin) are
// defined by the compiler-based implementation, not by the Abseil
// library. Therefore they do not use ABSL_INTERNAL_C_SYMBOL.
// Request the analysis tool to ignore all reads in the current thread until
// ABSL_ANNOTATE_IGNORE_READS_END is called. Useful to ignore intentional racey
// reads, while still checking other reads and all writes.
// See also ABSL_ANNOTATE_UNPROTECTED_READ.
#define ABSL_ANNOTATE_IGNORE_READS_BEGIN() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreReadsBegin) \
(__FILE__, __LINE__)
// Stop ignoring reads.
#define ABSL_ANNOTATE_IGNORE_READS_END() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreReadsEnd) \
(__FILE__, __LINE__)
// Function prototypes of annotations provided by the compiler-based sanitizer
// implementation.
ABSL_INTERNAL_BEGIN_EXTERN_C
void AnnotateIgnoreReadsBegin(const char* file, int line)
ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE;
void AnnotateIgnoreReadsEnd(const char* file,
int line) ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE;
ABSL_INTERNAL_END_EXTERN_C
#elif defined(ABSL_INTERNAL_ANNOTALYSIS_ENABLED)
// When Annotalysis is enabled without Dynamic Annotations, the use of
// static-inline functions allows the annotations to be read at compile-time,
// while still letting the compiler elide the functions from the final build.
//
// TODO(delesley) -- The exclusive lock here ignores writes as well, but
// allows IGNORE_READS_AND_WRITES to work properly.
#define ABSL_ANNOTATE_IGNORE_READS_BEGIN() \
ABSL_INTERNAL_GLOBAL_SCOPED( \
ABSL_INTERNAL_C_SYMBOL(AbslInternalAnnotateIgnoreReadsBegin)) \
()
#define ABSL_ANNOTATE_IGNORE_READS_END() \
ABSL_INTERNAL_GLOBAL_SCOPED( \
ABSL_INTERNAL_C_SYMBOL(AbslInternalAnnotateIgnoreReadsEnd)) \
()
ABSL_INTERNAL_STATIC_INLINE void ABSL_INTERNAL_C_SYMBOL(
AbslInternalAnnotateIgnoreReadsBegin)()
ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE {}
ABSL_INTERNAL_STATIC_INLINE void ABSL_INTERNAL_C_SYMBOL(
AbslInternalAnnotateIgnoreReadsEnd)()
ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE {}
#else
#define ABSL_ANNOTATE_IGNORE_READS_BEGIN() // empty
#define ABSL_ANNOTATE_IGNORE_READS_END() // empty
#endif
// -------------------------------------------------------------------------
// Define IGNORE_WRITES_BEGIN/_END annotations.
#if ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED == 1
// Similar to ABSL_ANNOTATE_IGNORE_READS_BEGIN, but ignore writes instead.
#define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreWritesBegin)(__FILE__, __LINE__)
// Stop ignoring writes.
#define ABSL_ANNOTATE_IGNORE_WRITES_END() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreWritesEnd)(__FILE__, __LINE__)
// Function prototypes of annotations provided by the compiler-based sanitizer
// implementation.
ABSL_INTERNAL_BEGIN_EXTERN_C
void AnnotateIgnoreWritesBegin(const char* file, int line);
void AnnotateIgnoreWritesEnd(const char* file, int line);
ABSL_INTERNAL_END_EXTERN_C
#else
#define ABSL_ANNOTATE_IGNORE_WRITES_BEGIN() // empty
#define ABSL_ANNOTATE_IGNORE_WRITES_END() // empty
#endif
// -------------------------------------------------------------------------
// Define the ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_* annotations using the more
// primitive annotations defined above.
//
// Instead of doing
// ABSL_ANNOTATE_IGNORE_READS_BEGIN();
// ... = x;
// ABSL_ANNOTATE_IGNORE_READS_END();
// one can use
// ... = ABSL_ANNOTATE_UNPROTECTED_READ(x);
#if defined(ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED)
// Start ignoring all memory accesses (both reads and writes).
#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN() \
do { \
ABSL_ANNOTATE_IGNORE_READS_BEGIN(); \
ABSL_ANNOTATE_IGNORE_WRITES_BEGIN(); \
} while (0)
// Stop ignoring both reads and writes.
#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_END() \
do { \
ABSL_ANNOTATE_IGNORE_WRITES_END(); \
ABSL_ANNOTATE_IGNORE_READS_END(); \
} while (0)
#ifdef __cplusplus
// ABSL_ANNOTATE_UNPROTECTED_READ is the preferred way to annotate racey reads.
#define ABSL_ANNOTATE_UNPROTECTED_READ(x) \
absl::base_internal::AnnotateUnprotectedRead(x)
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
template <typename T>
inline T AnnotateUnprotectedRead(const volatile T& x) { // NOLINT
ABSL_ANNOTATE_IGNORE_READS_BEGIN();
T res = x;
ABSL_ANNOTATE_IGNORE_READS_END();
return res;
}
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif
#else
#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN() // empty
#define ABSL_ANNOTATE_IGNORE_READS_AND_WRITES_END() // empty
#define ABSL_ANNOTATE_UNPROTECTED_READ(x) (x)
#endif
// -------------------------------------------------------------------------
// Address sanitizer annotations
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
// Describe the current state of a contiguous container such as e.g.
// std::vector or std::string. For more details see
// sanitizer/common_interface_defs.h, which is provided by the compiler.
#include <sanitizer/common_interface_defs.h>
#define ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(beg, end, old_mid, new_mid) \
__sanitizer_annotate_contiguous_container(beg, end, old_mid, new_mid)
#define ABSL_ADDRESS_SANITIZER_REDZONE(name) \
struct { \
alignas(8) char x[8]; \
} name
#else
#define ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(beg, end, old_mid, new_mid) // empty
#define ABSL_ADDRESS_SANITIZER_REDZONE(name) static_assert(true, "")
#endif // ABSL_HAVE_ADDRESS_SANITIZER
// -------------------------------------------------------------------------
// HWAddress sanitizer annotations
#ifdef __cplusplus
namespace absl {
#ifdef ABSL_HAVE_HWADDRESS_SANITIZER
// Under HWASAN changes the tag of the pointer.
template <typename T>
T* HwasanTagPointer(T* ptr, uintptr_t tag) {
return reinterpret_cast<T*>(__hwasan_tag_pointer(ptr, tag));
}
#else
template <typename T>
T* HwasanTagPointer(T* ptr, uintptr_t) {
return ptr;
}
#endif
} // namespace absl
#endif
// -------------------------------------------------------------------------
// Undefine the macros intended only for this file.
#undef ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_ANNOTALYSIS_ENABLED
#undef ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_BEGIN_EXTERN_C
#undef ABSL_INTERNAL_END_EXTERN_C
#undef ABSL_INTERNAL_STATIC_INLINE
#endif // ABSL_BASE_DYNAMIC_ANNOTATIONS_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_ATOMIC_HOOK_H_
#define ABSL_BASE_INTERNAL_ATOMIC_HOOK_H_
#include <atomic>
#include <cassert>
#include <cstdint>
#include <utility>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#if defined(_MSC_VER) && !defined(__clang__)
#define ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT 0
#else
#define ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT 1
#endif
#if defined(_MSC_VER)
#define ABSL_HAVE_WORKING_ATOMIC_POINTER 0
#else
#define ABSL_HAVE_WORKING_ATOMIC_POINTER 1
#endif
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
template <typename T>
class AtomicHook;
// To workaround AtomicHook not being constant-initializable on some platforms,
// prefer to annotate instances with `ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES`
// instead of `ABSL_CONST_INIT`.
#if ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
#define ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_CONST_INIT
#else
#define ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES
#endif
// `AtomicHook` is a helper class, templatized on a raw function pointer type,
// for implementing Abseil customization hooks. It is a callable object that
// dispatches to the registered hook. Objects of type `AtomicHook` must have
// static or thread storage duration.
//
// A default constructed object performs a no-op (and returns a default
// constructed object) if no hook has been registered.
//
// Hooks can be pre-registered via constant initialization, for example:
//
// ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static AtomicHook<void(*)()>
// my_hook(DefaultAction);
//
// and then changed at runtime via a call to `Store()`.
//
// Reads and writes guarantee memory_order_acquire/memory_order_release
// semantics.
template <typename ReturnType, typename... Args>
class AtomicHook<ReturnType (*)(Args...)> {
public:
using FnPtr = ReturnType (*)(Args...);
// Constructs an object that by default performs a no-op (and
// returns a default constructed object) when no hook as been registered.
constexpr AtomicHook() : AtomicHook(DummyFunction) {}
// Constructs an object that by default dispatches to/returns the
// pre-registered default_fn when no hook has been registered at runtime.
#if ABSL_HAVE_WORKING_ATOMIC_POINTER && ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
explicit constexpr AtomicHook(FnPtr default_fn)
: hook_(default_fn), default_fn_(default_fn) {}
#elif ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
explicit constexpr AtomicHook(FnPtr default_fn)
: hook_(kUninitialized), default_fn_(default_fn) {}
#else
// As of January 2020, on all known versions of MSVC this constructor runs in
// the global constructor sequence. If `Store()` is called by a dynamic
// initializer, we want to preserve the value, even if this constructor runs
// after the call to `Store()`. If not, `hook_` will be
// zero-initialized by the linker and we have no need to set it.
// https://developercommunity.visualstudio.com/content/problem/336946/class-with-constexpr-constructor-not-using-static.html
explicit constexpr AtomicHook(FnPtr default_fn)
: /* hook_(deliberately omitted), */ default_fn_(default_fn) {
static_assert(kUninitialized == 0, "here we rely on zero-initialization");
}
#endif
// Stores the provided function pointer as the value for this hook.
//
// This is intended to be called once. Multiple calls are legal only if the
// same function pointer is provided for each call. The store is implemented
// as a memory_order_release operation, and read accesses are implemented as
// memory_order_acquire.
void Store(FnPtr fn) {
bool success = DoStore(fn);
static_cast<void>(success);
assert(success);
}
// Invokes the registered callback. If no callback has yet been registered, a
// default-constructed object of the appropriate type is returned instead.
template <typename... CallArgs>
ReturnType operator()(CallArgs&&... args) const {
return DoLoad()(std::forward<CallArgs>(args)...);
}
// Returns the registered callback, or nullptr if none has been registered.
// Useful if client code needs to conditionalize behavior based on whether a
// callback was registered.
//
// Note that atomic_hook.Load()() and atomic_hook() have different semantics:
// operator()() will perform a no-op if no callback was registered, while
// Load()() will dereference a null function pointer. Prefer operator()() to
// Load()() unless you must conditionalize behavior on whether a hook was
// registered.
FnPtr Load() const {
FnPtr ptr = DoLoad();
return (ptr == DummyFunction) ? nullptr : ptr;
}
private:
static ReturnType DummyFunction(Args...) {
return ReturnType();
}
// Current versions of MSVC (as of September 2017) have a broken
// implementation of std::atomic<T*>: Its constructor attempts to do the
// equivalent of a reinterpret_cast in a constexpr context, which is not
// allowed.
//
// This causes an issue when building with LLVM under Windows. To avoid this,
// we use a less-efficient, intptr_t-based implementation on Windows.
#if ABSL_HAVE_WORKING_ATOMIC_POINTER
// Return the stored value, or DummyFunction if no value has been stored.
FnPtr DoLoad() const { return hook_.load(std::memory_order_acquire); }
// Store the given value. Returns false if a different value was already
// stored to this object.
bool DoStore(FnPtr fn) {
assert(fn);
FnPtr expected = default_fn_;
const bool store_succeeded = hook_.compare_exchange_strong(
expected, fn, std::memory_order_acq_rel, std::memory_order_acquire);
const bool same_value_already_stored = (expected == fn);
return store_succeeded || same_value_already_stored;
}
std::atomic<FnPtr> hook_;
#else // !ABSL_HAVE_WORKING_ATOMIC_POINTER
// Use a sentinel value unlikely to be the address of an actual function.
static constexpr intptr_t kUninitialized = 0;
static_assert(sizeof(intptr_t) >= sizeof(FnPtr),
"intptr_t can't contain a function pointer");
FnPtr DoLoad() const {
const intptr_t value = hook_.load(std::memory_order_acquire);
if (value == kUninitialized) {
return default_fn_;
}
return reinterpret_cast<FnPtr>(value);
}
bool DoStore(FnPtr fn) {
assert(fn);
const auto value = reinterpret_cast<intptr_t>(fn);
intptr_t expected = kUninitialized;
const bool store_succeeded = hook_.compare_exchange_strong(
expected, value, std::memory_order_acq_rel, std::memory_order_acquire);
const bool same_value_already_stored = (expected == value);
return store_succeeded || same_value_already_stored;
}
std::atomic<intptr_t> hook_;
#endif
const FnPtr default_fn_;
};
#undef ABSL_HAVE_WORKING_ATOMIC_POINTER
#undef ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_ATOMIC_HOOK_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_ATOMIC_HOOK_TEST_HELPER_H_
#define ABSL_BASE_INTERNAL_ATOMIC_HOOK_TEST_HELPER_H_
#include "absl/base/internal/atomic_hook.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace atomic_hook_internal {
using VoidF = void (*)();
extern absl::base_internal::AtomicHook<VoidF> func;
extern int default_func_calls;
void DefaultFunc();
void RegisterFunc(VoidF func);
} // namespace atomic_hook_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_ATOMIC_HOOK_TEST_HELPER_H_

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//
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: cycleclock.h
// -----------------------------------------------------------------------------
//
// This header file defines a `CycleClock`, which yields the value and frequency
// of a cycle counter that increments at a rate that is approximately constant.
//
// NOTE:
//
// The cycle counter frequency is not necessarily related to the core clock
// frequency and should not be treated as such. That is, `CycleClock` cycles are
// not necessarily "CPU cycles" and code should not rely on that behavior, even
// if experimentally observed.
//
// An arbitrary offset may have been added to the counter at power on.
//
// On some platforms, the rate and offset of the counter may differ
// slightly when read from different CPUs of a multiprocessor. Usually,
// we try to ensure that the operating system adjusts values periodically
// so that values agree approximately. If you need stronger guarantees,
// consider using alternate interfaces.
//
// The CPU is not required to maintain the ordering of a cycle counter read
// with respect to surrounding instructions.
#ifndef ABSL_BASE_INTERNAL_CYCLECLOCK_H_
#define ABSL_BASE_INTERNAL_CYCLECLOCK_H_
#include <atomic>
#include <cstdint>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#include "absl/base/internal/cycleclock_config.h"
#include "absl/base/internal/unscaledcycleclock.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
using CycleClockSourceFunc = int64_t (*)();
// -----------------------------------------------------------------------------
// CycleClock
// -----------------------------------------------------------------------------
class CycleClock {
public:
// CycleClock::Now()
//
// Returns the value of a cycle counter that counts at a rate that is
// approximately constant.
static int64_t Now();
// CycleClock::Frequency()
//
// Returns the amount by which `CycleClock::Now()` increases per second. Note
// that this value may not necessarily match the core CPU clock frequency.
static double Frequency();
private:
#if ABSL_USE_UNSCALED_CYCLECLOCK
static CycleClockSourceFunc LoadCycleClockSource();
static constexpr int32_t kShift = kCycleClockShift;
static constexpr double kFrequencyScale = kCycleClockFrequencyScale;
ABSL_CONST_INIT static std::atomic<CycleClockSourceFunc> cycle_clock_source_;
#endif // ABSL_USE_UNSCALED_CYCLECLOC
CycleClock() = delete; // no instances
CycleClock(const CycleClock&) = delete;
CycleClock& operator=(const CycleClock&) = delete;
friend class CycleClockSource;
};
class CycleClockSource {
private:
// CycleClockSource::Register()
//
// Register a function that provides an alternate source for the unscaled CPU
// cycle count value. The source function must be async signal safe, must not
// call CycleClock::Now(), and must have a frequency that matches that of the
// unscaled clock used by CycleClock. A nullptr value resets CycleClock to use
// the default source.
static void Register(CycleClockSourceFunc source);
};
#if ABSL_USE_UNSCALED_CYCLECLOCK
inline CycleClockSourceFunc CycleClock::LoadCycleClockSource() {
#if !defined(__x86_64__)
// Optimize for the common case (no callback) by first doing a relaxed load;
// this is significantly faster on non-x86 platforms.
if (cycle_clock_source_.load(std::memory_order_relaxed) == nullptr) {
return nullptr;
}
#endif // !defined(__x86_64__)
// This corresponds to the store(std::memory_order_release) in
// CycleClockSource::Register, and makes sure that any updates made prior to
// registering the callback are visible to this thread before the callback
// is invoked.
return cycle_clock_source_.load(std::memory_order_acquire);
}
// Accessing globals in inlined code in Window DLLs is problematic.
#ifndef _WIN32
inline int64_t CycleClock::Now() {
auto fn = LoadCycleClockSource();
if (fn == nullptr) {
return base_internal::UnscaledCycleClock::Now() >> kShift;
}
return fn() >> kShift;
}
#endif
inline double CycleClock::Frequency() {
return kFrequencyScale * base_internal::UnscaledCycleClock::Frequency();
}
#endif // ABSL_USE_UNSCALED_CYCLECLOCK
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_CYCLECLOCK_H_

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// Copyright 2022 The Abseil Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_CYCLECLOCK_CONFIG_H_
#define ABSL_BASE_INTERNAL_CYCLECLOCK_CONFIG_H_
#include <cstdint>
#include "absl/base/config.h"
#include "absl/base/internal/inline_variable.h"
#include "absl/base/internal/unscaledcycleclock_config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
#if ABSL_USE_UNSCALED_CYCLECLOCK
#ifdef NDEBUG
#ifdef ABSL_INTERNAL_UNSCALED_CYCLECLOCK_FREQUENCY_IS_CPU_FREQUENCY
// Not debug mode and the UnscaledCycleClock frequency is the CPU
// frequency. Scale the CycleClock to prevent overflow if someone
// tries to represent the time as cycles since the Unix epoch.
ABSL_INTERNAL_INLINE_CONSTEXPR(int32_t, kCycleClockShift, 1);
#else
// Not debug mode and the UnscaledCycleClock isn't operating at the
// raw CPU frequency. There is no need to do any scaling, so don't
// needlessly sacrifice precision.
ABSL_INTERNAL_INLINE_CONSTEXPR(int32_t, kCycleClockShift, 0);
#endif
#else // NDEBUG
// In debug mode use a different shift to discourage depending on a
// particular shift value.
ABSL_INTERNAL_INLINE_CONSTEXPR(int32_t, kCycleClockShift, 2);
#endif // NDEBUG
ABSL_INTERNAL_INLINE_CONSTEXPR(double, kCycleClockFrequencyScale,
1.0 / (1 << kCycleClockShift));
#endif // ABSL_USE_UNSCALED_CYCLECLOC
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_CYCLECLOCK_CONFIG_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Functions for directly invoking mmap() via syscall, avoiding the case where
// mmap() has been locally overridden.
#ifndef ABSL_BASE_INTERNAL_DIRECT_MMAP_H_
#define ABSL_BASE_INTERNAL_DIRECT_MMAP_H_
#include "absl/base/config.h"
#ifdef ABSL_HAVE_MMAP
#include <sys/mman.h>
#ifdef __linux__
#include <sys/types.h>
#ifdef __BIONIC__
#include <sys/syscall.h>
#else
#include <syscall.h>
#endif
#include <linux/unistd.h>
#include <unistd.h>
#include <cerrno>
#include <cstdarg>
#include <cstdint>
#ifdef __mips__
// Include definitions of the ABI currently in use.
#if defined(__BIONIC__) || !defined(__GLIBC__)
// Android doesn't have sgidefs.h, but does have asm/sgidefs.h, which has the
// definitions we need.
#include <asm/sgidefs.h>
#else
#include <sgidefs.h>
#endif // __BIONIC__ || !__GLIBC__
#endif // __mips__
// SYS_mmap and SYS_munmap are not defined in Android.
#ifdef __BIONIC__
extern "C" void* __mmap2(void*, size_t, int, int, int, size_t);
#if defined(__NR_mmap) && !defined(SYS_mmap)
#define SYS_mmap __NR_mmap
#endif
#ifndef SYS_munmap
#define SYS_munmap __NR_munmap
#endif
#endif // __BIONIC__
#if defined(__NR_mmap2) && !defined(SYS_mmap2)
#define SYS_mmap2 __NR_mmap2
#endif
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// Platform specific logic extracted from
// https://chromium.googlesource.com/linux-syscall-support/+/master/linux_syscall_support.h
inline void* DirectMmap(void* start, size_t length, int prot, int flags, int fd,
off_t offset) noexcept {
#if defined(__i386__) || defined(__ARM_ARCH_3__) || defined(__ARM_EABI__) || \
defined(__m68k__) || defined(__sh__) || \
(defined(__hppa__) && !defined(__LP64__)) || \
(defined(__mips__) && _MIPS_SIM == _MIPS_SIM_ABI32) || \
(defined(__PPC__) && !defined(__PPC64__)) || \
(defined(__riscv) && __riscv_xlen == 32) || \
(defined(__s390__) && !defined(__s390x__)) || \
(defined(__sparc__) && !defined(__arch64__))
// On these architectures, implement mmap with mmap2.
static int pagesize = 0;
if (pagesize == 0) {
#if defined(__wasm__) || defined(__asmjs__)
pagesize = getpagesize();
#else
pagesize = sysconf(_SC_PAGESIZE);
#endif
}
if (offset < 0 || offset % pagesize != 0) {
errno = EINVAL;
return MAP_FAILED;
}
#ifdef __BIONIC__
// SYS_mmap2 has problems on Android API level <= 16.
// Workaround by invoking __mmap2() instead.
return __mmap2(start, length, prot, flags, fd,
static_cast<size_t>(offset / pagesize));
#else
return reinterpret_cast<void*>(
syscall(SYS_mmap2, start, length, prot, flags, fd,
static_cast<unsigned long>(offset / pagesize))); // NOLINT
#endif
#elif defined(__s390x__)
// On s390x, mmap() arguments are passed in memory.
unsigned long buf[6] = {reinterpret_cast<unsigned long>(start), // NOLINT
static_cast<unsigned long>(length), // NOLINT
static_cast<unsigned long>(prot), // NOLINT
static_cast<unsigned long>(flags), // NOLINT
static_cast<unsigned long>(fd), // NOLINT
static_cast<unsigned long>(offset)}; // NOLINT
return reinterpret_cast<void*>(syscall(SYS_mmap, buf));
#elif defined(__x86_64__)
// The x32 ABI has 32 bit longs, but the syscall interface is 64 bit.
// We need to explicitly cast to an unsigned 64 bit type to avoid implicit
// sign extension. We can't cast pointers directly because those are
// 32 bits, and gcc will dump ugly warnings about casting from a pointer
// to an integer of a different size. We also need to make sure __off64_t
// isn't truncated to 32-bits under x32.
#define MMAP_SYSCALL_ARG(x) ((uint64_t)(uintptr_t)(x))
return reinterpret_cast<void*>(
syscall(SYS_mmap, MMAP_SYSCALL_ARG(start), MMAP_SYSCALL_ARG(length),
MMAP_SYSCALL_ARG(prot), MMAP_SYSCALL_ARG(flags),
MMAP_SYSCALL_ARG(fd), static_cast<uint64_t>(offset)));
#undef MMAP_SYSCALL_ARG
#else // Remaining 64-bit aritectures.
static_assert(sizeof(unsigned long) == 8, "Platform is not 64-bit");
return reinterpret_cast<void*>(
syscall(SYS_mmap, start, length, prot, flags, fd, offset));
#endif
}
inline int DirectMunmap(void* start, size_t length) {
return static_cast<int>(syscall(SYS_munmap, start, length));
}
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#else // !__linux__
// For non-linux platforms where we have mmap, just dispatch directly to the
// actual mmap()/munmap() methods.
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
inline void* DirectMmap(void* start, size_t length, int prot, int flags, int fd,
off_t offset) {
return mmap(start, length, prot, flags, fd, offset);
}
inline int DirectMunmap(void* start, size_t length) {
return munmap(start, length);
}
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // __linux__
#endif // ABSL_HAVE_MMAP
#endif // ABSL_BASE_INTERNAL_DIRECT_MMAP_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// This file defines dynamic annotations for use with dynamic analysis tool
// such as valgrind, PIN, etc.
//
// Dynamic annotation is a source code annotation that affects the generated
// code (that is, the annotation is not a comment). Each such annotation is
// attached to a particular instruction and/or to a particular object (address)
// in the program.
//
// The annotations that should be used by users are macros in all upper-case
// (e.g., ANNOTATE_THREAD_NAME).
//
// Actual implementation of these macros may differ depending on the dynamic
// analysis tool being used.
//
// This file supports the following configurations:
// - Dynamic Annotations enabled (with static thread-safety warnings disabled).
// In this case, macros expand to functions implemented by Thread Sanitizer,
// when building with TSan. When not provided an external implementation,
// dynamic_annotations.cc provides no-op implementations.
//
// - Static Clang thread-safety warnings enabled.
// When building with a Clang compiler that supports thread-safety warnings,
// a subset of annotations can be statically-checked at compile-time. We
// expand these macros to static-inline functions that can be analyzed for
// thread-safety, but afterwards elided when building the final binary.
//
// - All annotations are disabled.
// If neither Dynamic Annotations nor Clang thread-safety warnings are
// enabled, then all annotation-macros expand to empty.
#ifndef ABSL_BASE_INTERNAL_DYNAMIC_ANNOTATIONS_H_
#define ABSL_BASE_INTERNAL_DYNAMIC_ANNOTATIONS_H_
#include <stddef.h>
#include "absl/base/config.h"
// -------------------------------------------------------------------------
// Decide which features are enabled
#ifndef DYNAMIC_ANNOTATIONS_ENABLED
#define DYNAMIC_ANNOTATIONS_ENABLED 0
#endif
#if defined(__clang__) && !defined(SWIG)
#define ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED 1
#endif
#if DYNAMIC_ANNOTATIONS_ENABLED != 0
#define ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED 1
#define ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED 1
#define ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED 1
#define ABSL_INTERNAL_ANNOTALYSIS_ENABLED 0
#define ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED 1
#else
#define ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED 0
#define ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED 0
#define ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED 0
// Clang provides limited support for static thread-safety analysis through a
// feature called Annotalysis. We configure macro-definitions according to
// whether Annotalysis support is available. When running in opt-mode, GCC
// will issue a warning, if these attributes are compiled. Only include them
// when compiling using Clang.
// ANNOTALYSIS_ENABLED == 1 when IGNORE_READ_ATTRIBUTE_ENABLED == 1
#define ABSL_INTERNAL_ANNOTALYSIS_ENABLED \
defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
// Read/write annotations are enabled in Annotalysis mode; disabled otherwise.
#define ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED \
ABSL_INTERNAL_ANNOTALYSIS_ENABLED
#endif
// Memory annotations are also made available to LLVM's Memory Sanitizer
#if defined(ABSL_HAVE_MEMORY_SANITIZER) && !defined(__native_client__)
#define ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED 1
#endif
#ifndef ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED
#define ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED 0
#endif
#ifdef __cplusplus
#define ABSL_INTERNAL_BEGIN_EXTERN_C extern "C" {
#define ABSL_INTERNAL_END_EXTERN_C } // extern "C"
#define ABSL_INTERNAL_GLOBAL_SCOPED(F) ::F
#define ABSL_INTERNAL_STATIC_INLINE inline
#else
#define ABSL_INTERNAL_BEGIN_EXTERN_C // empty
#define ABSL_INTERNAL_END_EXTERN_C // empty
#define ABSL_INTERNAL_GLOBAL_SCOPED(F) F
#define ABSL_INTERNAL_STATIC_INLINE static inline
#endif
// -------------------------------------------------------------------------
// Define race annotations.
#if ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED == 1
// -------------------------------------------------------------
// Annotations that suppress errors. It is usually better to express the
// program's synchronization using the other annotations, but these can be used
// when all else fails.
// Report that we may have a benign race at `pointer`, with size
// "sizeof(*(pointer))". `pointer` must be a non-void* pointer. Insert at the
// point where `pointer` has been allocated, preferably close to the point
// where the race happens. See also ANNOTATE_BENIGN_RACE_STATIC.
#define ANNOTATE_BENIGN_RACE(pointer, description) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateBenignRaceSized) \
(__FILE__, __LINE__, pointer, sizeof(*(pointer)), description)
// Same as ANNOTATE_BENIGN_RACE(`address`, `description`), but applies to
// the memory range [`address`, `address`+`size`).
#define ANNOTATE_BENIGN_RACE_SIZED(address, size, description) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateBenignRaceSized) \
(__FILE__, __LINE__, address, size, description)
// Enable (`enable`!=0) or disable (`enable`==0) race detection for all threads.
// This annotation could be useful if you want to skip expensive race analysis
// during some period of program execution, e.g. during initialization.
#define ANNOTATE_ENABLE_RACE_DETECTION(enable) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateEnableRaceDetection) \
(__FILE__, __LINE__, enable)
// -------------------------------------------------------------
// Annotations useful for debugging.
// Report the current thread `name` to a race detector.
#define ANNOTATE_THREAD_NAME(name) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateThreadName)(__FILE__, __LINE__, name)
// -------------------------------------------------------------
// Annotations useful when implementing locks. They are not normally needed by
// modules that merely use locks. The `lock` argument is a pointer to the lock
// object.
// Report that a lock has been created at address `lock`.
#define ANNOTATE_RWLOCK_CREATE(lock) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockCreate)(__FILE__, __LINE__, lock)
// Report that a linker initialized lock has been created at address `lock`.
#ifdef ABSL_HAVE_THREAD_SANITIZER
#define ANNOTATE_RWLOCK_CREATE_STATIC(lock) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockCreateStatic) \
(__FILE__, __LINE__, lock)
#else
#define ANNOTATE_RWLOCK_CREATE_STATIC(lock) ANNOTATE_RWLOCK_CREATE(lock)
#endif
// Report that the lock at address `lock` is about to be destroyed.
#define ANNOTATE_RWLOCK_DESTROY(lock) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockDestroy)(__FILE__, __LINE__, lock)
// Report that the lock at address `lock` has been acquired.
// `is_w`=1 for writer lock, `is_w`=0 for reader lock.
#define ANNOTATE_RWLOCK_ACQUIRED(lock, is_w) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockAcquired) \
(__FILE__, __LINE__, lock, is_w)
// Report that the lock at address `lock` is about to be released.
// `is_w`=1 for writer lock, `is_w`=0 for reader lock.
#define ANNOTATE_RWLOCK_RELEASED(lock, is_w) \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateRWLockReleased) \
(__FILE__, __LINE__, lock, is_w)
// Apply ANNOTATE_BENIGN_RACE_SIZED to a static variable `static_var`.
#define ANNOTATE_BENIGN_RACE_STATIC(static_var, description) \
namespace { \
class static_var##_annotator { \
public: \
static_var##_annotator() { \
ANNOTATE_BENIGN_RACE_SIZED(&static_var, sizeof(static_var), \
#static_var ": " description); \
} \
}; \
static static_var##_annotator the##static_var##_annotator; \
} // namespace
#else // ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED == 0
#define ANNOTATE_RWLOCK_CREATE(lock) // empty
#define ANNOTATE_RWLOCK_CREATE_STATIC(lock) // empty
#define ANNOTATE_RWLOCK_DESTROY(lock) // empty
#define ANNOTATE_RWLOCK_ACQUIRED(lock, is_w) // empty
#define ANNOTATE_RWLOCK_RELEASED(lock, is_w) // empty
#define ANNOTATE_BENIGN_RACE(address, description) // empty
#define ANNOTATE_BENIGN_RACE_SIZED(address, size, description) // empty
#define ANNOTATE_THREAD_NAME(name) // empty
#define ANNOTATE_ENABLE_RACE_DETECTION(enable) // empty
#define ANNOTATE_BENIGN_RACE_STATIC(static_var, description) // empty
#endif // ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED
// -------------------------------------------------------------------------
// Define memory annotations.
#if ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED == 1
#include <sanitizer/msan_interface.h>
#define ANNOTATE_MEMORY_IS_INITIALIZED(address, size) \
__msan_unpoison(address, size)
#define ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) \
__msan_allocated_memory(address, size)
#else // ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED == 0
#if DYNAMIC_ANNOTATIONS_ENABLED == 1
#define ANNOTATE_MEMORY_IS_INITIALIZED(address, size) \
do { \
(void)(address); \
(void)(size); \
} while (0)
#define ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) \
do { \
(void)(address); \
(void)(size); \
} while (0)
#else
#define ANNOTATE_MEMORY_IS_INITIALIZED(address, size) // empty
#define ANNOTATE_MEMORY_IS_UNINITIALIZED(address, size) // empty
#endif
#endif // ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED
// -------------------------------------------------------------------------
// Define IGNORE_READS_BEGIN/_END attributes.
#if defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
#define ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE \
__attribute((exclusive_lock_function("*")))
#define ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE \
__attribute((unlock_function("*")))
#else // !defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
#define ABSL_INTERNAL_IGNORE_READS_BEGIN_ATTRIBUTE // empty
#define ABSL_INTERNAL_IGNORE_READS_END_ATTRIBUTE // empty
#endif // defined(ABSL_INTERNAL_IGNORE_READS_ATTRIBUTE_ENABLED)
// -------------------------------------------------------------------------
// Define IGNORE_READS_BEGIN/_END annotations.
#if ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED == 1
// Request the analysis tool to ignore all reads in the current thread until
// ANNOTATE_IGNORE_READS_END is called. Useful to ignore intentional racey
// reads, while still checking other reads and all writes.
// See also ANNOTATE_UNPROTECTED_READ.
#define ANNOTATE_IGNORE_READS_BEGIN() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreReadsBegin)(__FILE__, __LINE__)
// Stop ignoring reads.
#define ANNOTATE_IGNORE_READS_END() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreReadsEnd)(__FILE__, __LINE__)
#elif defined(ABSL_INTERNAL_ANNOTALYSIS_ENABLED)
// When Annotalysis is enabled without Dynamic Annotations, the use of
// static-inline functions allows the annotations to be read at compile-time,
// while still letting the compiler elide the functions from the final build.
//
// TODO(delesley) -- The exclusive lock here ignores writes as well, but
// allows IGNORE_READS_AND_WRITES to work properly.
#define ANNOTATE_IGNORE_READS_BEGIN() \
ABSL_INTERNAL_GLOBAL_SCOPED(AbslInternalAnnotateIgnoreReadsBegin)()
#define ANNOTATE_IGNORE_READS_END() \
ABSL_INTERNAL_GLOBAL_SCOPED(AbslInternalAnnotateIgnoreReadsEnd)()
#else
#define ANNOTATE_IGNORE_READS_BEGIN() // empty
#define ANNOTATE_IGNORE_READS_END() // empty
#endif
// -------------------------------------------------------------------------
// Define IGNORE_WRITES_BEGIN/_END annotations.
#if ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED == 1
// Similar to ANNOTATE_IGNORE_READS_BEGIN, but ignore writes instead.
#define ANNOTATE_IGNORE_WRITES_BEGIN() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreWritesBegin)(__FILE__, __LINE__)
// Stop ignoring writes.
#define ANNOTATE_IGNORE_WRITES_END() \
ABSL_INTERNAL_GLOBAL_SCOPED(AnnotateIgnoreWritesEnd)(__FILE__, __LINE__)
#else
#define ANNOTATE_IGNORE_WRITES_BEGIN() // empty
#define ANNOTATE_IGNORE_WRITES_END() // empty
#endif
// -------------------------------------------------------------------------
// Define the ANNOTATE_IGNORE_READS_AND_WRITES_* annotations using the more
// primitive annotations defined above.
//
// Instead of doing
// ANNOTATE_IGNORE_READS_BEGIN();
// ... = x;
// ANNOTATE_IGNORE_READS_END();
// one can use
// ... = ANNOTATE_UNPROTECTED_READ(x);
#if defined(ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED)
// Start ignoring all memory accesses (both reads and writes).
#define ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN() \
do { \
ANNOTATE_IGNORE_READS_BEGIN(); \
ANNOTATE_IGNORE_WRITES_BEGIN(); \
} while (0)
// Stop ignoring both reads and writes.
#define ANNOTATE_IGNORE_READS_AND_WRITES_END() \
do { \
ANNOTATE_IGNORE_WRITES_END(); \
ANNOTATE_IGNORE_READS_END(); \
} while (0)
#ifdef __cplusplus
// ANNOTATE_UNPROTECTED_READ is the preferred way to annotate racey reads.
#define ANNOTATE_UNPROTECTED_READ(x) \
absl::base_internal::AnnotateUnprotectedRead(x)
#endif
#else
#define ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN() // empty
#define ANNOTATE_IGNORE_READS_AND_WRITES_END() // empty
#define ANNOTATE_UNPROTECTED_READ(x) (x)
#endif
// -------------------------------------------------------------------------
// Address sanitizer annotations
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
// Describe the current state of a contiguous container such as e.g.
// std::vector or std::string. For more details see
// sanitizer/common_interface_defs.h, which is provided by the compiler.
#include <sanitizer/common_interface_defs.h>
#define ANNOTATE_CONTIGUOUS_CONTAINER(beg, end, old_mid, new_mid) \
__sanitizer_annotate_contiguous_container(beg, end, old_mid, new_mid)
#define ADDRESS_SANITIZER_REDZONE(name) \
struct { \
char x[8] __attribute__((aligned(8))); \
} name
#else
#define ANNOTATE_CONTIGUOUS_CONTAINER(beg, end, old_mid, new_mid)
#define ADDRESS_SANITIZER_REDZONE(name) static_assert(true, "")
#endif // ABSL_HAVE_ADDRESS_SANITIZER
// -------------------------------------------------------------------------
// Undefine the macros intended only for this file.
#undef ABSL_INTERNAL_RACE_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_MEMORY_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_READS_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_WRITES_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_ANNOTALYSIS_ENABLED
#undef ABSL_INTERNAL_READS_WRITES_ANNOTATIONS_ENABLED
#undef ABSL_INTERNAL_BEGIN_EXTERN_C
#undef ABSL_INTERNAL_END_EXTERN_C
#undef ABSL_INTERNAL_STATIC_INLINE
#endif // ABSL_BASE_INTERNAL_DYNAMIC_ANNOTATIONS_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef ABSL_BASE_INTERNAL_ENDIAN_H_
#define ABSL_BASE_INTERNAL_ENDIAN_H_
#include <cstdint>
#include <cstdlib>
#include "absl/base/casts.h"
#include "absl/base/config.h"
#include "absl/base/internal/unaligned_access.h"
#include "absl/base/port.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
inline uint64_t gbswap_64(uint64_t host_int) {
#if ABSL_HAVE_BUILTIN(__builtin_bswap64) || defined(__GNUC__)
return __builtin_bswap64(host_int);
#elif defined(_MSC_VER)
return _byteswap_uint64(host_int);
#else
return (((host_int & uint64_t{0xFF}) << 56) |
((host_int & uint64_t{0xFF00}) << 40) |
((host_int & uint64_t{0xFF0000}) << 24) |
((host_int & uint64_t{0xFF000000}) << 8) |
((host_int & uint64_t{0xFF00000000}) >> 8) |
((host_int & uint64_t{0xFF0000000000}) >> 24) |
((host_int & uint64_t{0xFF000000000000}) >> 40) |
((host_int & uint64_t{0xFF00000000000000}) >> 56));
#endif
}
inline uint32_t gbswap_32(uint32_t host_int) {
#if ABSL_HAVE_BUILTIN(__builtin_bswap32) || defined(__GNUC__)
return __builtin_bswap32(host_int);
#elif defined(_MSC_VER)
return _byteswap_ulong(host_int);
#else
return (((host_int & uint32_t{0xFF}) << 24) |
((host_int & uint32_t{0xFF00}) << 8) |
((host_int & uint32_t{0xFF0000}) >> 8) |
((host_int & uint32_t{0xFF000000}) >> 24));
#endif
}
inline uint16_t gbswap_16(uint16_t host_int) {
#if ABSL_HAVE_BUILTIN(__builtin_bswap16) || defined(__GNUC__)
return __builtin_bswap16(host_int);
#elif defined(_MSC_VER)
return _byteswap_ushort(host_int);
#else
return (((host_int & uint16_t{0xFF}) << 8) |
((host_int & uint16_t{0xFF00}) >> 8));
#endif
}
#ifdef ABSL_IS_LITTLE_ENDIAN
// Portable definitions for htonl (host-to-network) and friends on little-endian
// architectures.
inline uint16_t ghtons(uint16_t x) { return gbswap_16(x); }
inline uint32_t ghtonl(uint32_t x) { return gbswap_32(x); }
inline uint64_t ghtonll(uint64_t x) { return gbswap_64(x); }
#elif defined ABSL_IS_BIG_ENDIAN
// Portable definitions for htonl (host-to-network) etc on big-endian
// architectures. These definitions are simpler since the host byte order is the
// same as network byte order.
inline uint16_t ghtons(uint16_t x) { return x; }
inline uint32_t ghtonl(uint32_t x) { return x; }
inline uint64_t ghtonll(uint64_t x) { return x; }
#else
#error \
"Unsupported byte order: Either ABSL_IS_BIG_ENDIAN or " \
"ABSL_IS_LITTLE_ENDIAN must be defined"
#endif // byte order
inline uint16_t gntohs(uint16_t x) { return ghtons(x); }
inline uint32_t gntohl(uint32_t x) { return ghtonl(x); }
inline uint64_t gntohll(uint64_t x) { return ghtonll(x); }
// Utilities to convert numbers between the current hosts's native byte
// order and little-endian byte order
//
// Load/Store methods are alignment safe
namespace little_endian {
// Conversion functions.
#ifdef ABSL_IS_LITTLE_ENDIAN
inline uint16_t FromHost16(uint16_t x) { return x; }
inline uint16_t ToHost16(uint16_t x) { return x; }
inline uint32_t FromHost32(uint32_t x) { return x; }
inline uint32_t ToHost32(uint32_t x) { return x; }
inline uint64_t FromHost64(uint64_t x) { return x; }
inline uint64_t ToHost64(uint64_t x) { return x; }
inline constexpr bool IsLittleEndian() { return true; }
#elif defined ABSL_IS_BIG_ENDIAN
inline uint16_t FromHost16(uint16_t x) { return gbswap_16(x); }
inline uint16_t ToHost16(uint16_t x) { return gbswap_16(x); }
inline uint32_t FromHost32(uint32_t x) { return gbswap_32(x); }
inline uint32_t ToHost32(uint32_t x) { return gbswap_32(x); }
inline uint64_t FromHost64(uint64_t x) { return gbswap_64(x); }
inline uint64_t ToHost64(uint64_t x) { return gbswap_64(x); }
inline constexpr bool IsLittleEndian() { return false; }
#endif /* ENDIAN */
inline uint8_t FromHost(uint8_t x) { return x; }
inline uint16_t FromHost(uint16_t x) { return FromHost16(x); }
inline uint32_t FromHost(uint32_t x) { return FromHost32(x); }
inline uint64_t FromHost(uint64_t x) { return FromHost64(x); }
inline uint8_t ToHost(uint8_t x) { return x; }
inline uint16_t ToHost(uint16_t x) { return ToHost16(x); }
inline uint32_t ToHost(uint32_t x) { return ToHost32(x); }
inline uint64_t ToHost(uint64_t x) { return ToHost64(x); }
inline int8_t FromHost(int8_t x) { return x; }
inline int16_t FromHost(int16_t x) {
return bit_cast<int16_t>(FromHost16(bit_cast<uint16_t>(x)));
}
inline int32_t FromHost(int32_t x) {
return bit_cast<int32_t>(FromHost32(bit_cast<uint32_t>(x)));
}
inline int64_t FromHost(int64_t x) {
return bit_cast<int64_t>(FromHost64(bit_cast<uint64_t>(x)));
}
inline int8_t ToHost(int8_t x) { return x; }
inline int16_t ToHost(int16_t x) {
return bit_cast<int16_t>(ToHost16(bit_cast<uint16_t>(x)));
}
inline int32_t ToHost(int32_t x) {
return bit_cast<int32_t>(ToHost32(bit_cast<uint32_t>(x)));
}
inline int64_t ToHost(int64_t x) {
return bit_cast<int64_t>(ToHost64(bit_cast<uint64_t>(x)));
}
// Functions to do unaligned loads and stores in little-endian order.
inline uint16_t Load16(const void *p) {
return ToHost16(ABSL_INTERNAL_UNALIGNED_LOAD16(p));
}
inline void Store16(void *p, uint16_t v) {
ABSL_INTERNAL_UNALIGNED_STORE16(p, FromHost16(v));
}
inline uint32_t Load32(const void *p) {
return ToHost32(ABSL_INTERNAL_UNALIGNED_LOAD32(p));
}
inline void Store32(void *p, uint32_t v) {
ABSL_INTERNAL_UNALIGNED_STORE32(p, FromHost32(v));
}
inline uint64_t Load64(const void *p) {
return ToHost64(ABSL_INTERNAL_UNALIGNED_LOAD64(p));
}
inline void Store64(void *p, uint64_t v) {
ABSL_INTERNAL_UNALIGNED_STORE64(p, FromHost64(v));
}
} // namespace little_endian
// Utilities to convert numbers between the current hosts's native byte
// order and big-endian byte order (same as network byte order)
//
// Load/Store methods are alignment safe
namespace big_endian {
#ifdef ABSL_IS_LITTLE_ENDIAN
inline uint16_t FromHost16(uint16_t x) { return gbswap_16(x); }
inline uint16_t ToHost16(uint16_t x) { return gbswap_16(x); }
inline uint32_t FromHost32(uint32_t x) { return gbswap_32(x); }
inline uint32_t ToHost32(uint32_t x) { return gbswap_32(x); }
inline uint64_t FromHost64(uint64_t x) { return gbswap_64(x); }
inline uint64_t ToHost64(uint64_t x) { return gbswap_64(x); }
inline constexpr bool IsLittleEndian() { return true; }
#elif defined ABSL_IS_BIG_ENDIAN
inline uint16_t FromHost16(uint16_t x) { return x; }
inline uint16_t ToHost16(uint16_t x) { return x; }
inline uint32_t FromHost32(uint32_t x) { return x; }
inline uint32_t ToHost32(uint32_t x) { return x; }
inline uint64_t FromHost64(uint64_t x) { return x; }
inline uint64_t ToHost64(uint64_t x) { return x; }
inline constexpr bool IsLittleEndian() { return false; }
#endif /* ENDIAN */
inline uint8_t FromHost(uint8_t x) { return x; }
inline uint16_t FromHost(uint16_t x) { return FromHost16(x); }
inline uint32_t FromHost(uint32_t x) { return FromHost32(x); }
inline uint64_t FromHost(uint64_t x) { return FromHost64(x); }
inline uint8_t ToHost(uint8_t x) { return x; }
inline uint16_t ToHost(uint16_t x) { return ToHost16(x); }
inline uint32_t ToHost(uint32_t x) { return ToHost32(x); }
inline uint64_t ToHost(uint64_t x) { return ToHost64(x); }
inline int8_t FromHost(int8_t x) { return x; }
inline int16_t FromHost(int16_t x) {
return bit_cast<int16_t>(FromHost16(bit_cast<uint16_t>(x)));
}
inline int32_t FromHost(int32_t x) {
return bit_cast<int32_t>(FromHost32(bit_cast<uint32_t>(x)));
}
inline int64_t FromHost(int64_t x) {
return bit_cast<int64_t>(FromHost64(bit_cast<uint64_t>(x)));
}
inline int8_t ToHost(int8_t x) { return x; }
inline int16_t ToHost(int16_t x) {
return bit_cast<int16_t>(ToHost16(bit_cast<uint16_t>(x)));
}
inline int32_t ToHost(int32_t x) {
return bit_cast<int32_t>(ToHost32(bit_cast<uint32_t>(x)));
}
inline int64_t ToHost(int64_t x) {
return bit_cast<int64_t>(ToHost64(bit_cast<uint64_t>(x)));
}
// Functions to do unaligned loads and stores in big-endian order.
inline uint16_t Load16(const void *p) {
return ToHost16(ABSL_INTERNAL_UNALIGNED_LOAD16(p));
}
inline void Store16(void *p, uint16_t v) {
ABSL_INTERNAL_UNALIGNED_STORE16(p, FromHost16(v));
}
inline uint32_t Load32(const void *p) {
return ToHost32(ABSL_INTERNAL_UNALIGNED_LOAD32(p));
}
inline void Store32(void *p, uint32_t v) {
ABSL_INTERNAL_UNALIGNED_STORE32(p, FromHost32(v));
}
inline uint64_t Load64(const void *p) {
return ToHost64(ABSL_INTERNAL_UNALIGNED_LOAD64(p));
}
inline void Store64(void *p, uint64_t v) {
ABSL_INTERNAL_UNALIGNED_STORE64(p, FromHost64(v));
}
} // namespace big_endian
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_ENDIAN_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_ERRNO_SAVER_H_
#define ABSL_BASE_INTERNAL_ERRNO_SAVER_H_
#include <cerrno>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// `ErrnoSaver` captures the value of `errno` upon construction and restores it
// upon deletion. It is used in low-level code and must be super fast. Do not
// add instrumentation, even in debug modes.
class ErrnoSaver {
public:
ErrnoSaver() : saved_errno_(errno) {}
~ErrnoSaver() { errno = saved_errno_; }
int operator()() const { return saved_errno_; }
private:
const int saved_errno_;
};
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_ERRNO_SAVER_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Testing utilities for ABSL types which throw exceptions.
#ifndef ABSL_BASE_INTERNAL_EXCEPTION_TESTING_H_
#define ABSL_BASE_INTERNAL_EXCEPTION_TESTING_H_
#include "gtest/gtest.h"
#include "absl/base/config.h"
// ABSL_BASE_INTERNAL_EXPECT_FAIL tests either for a specified thrown exception
// if exceptions are enabled, or for death with a specified text in the error
// message
#ifdef ABSL_HAVE_EXCEPTIONS
#define ABSL_BASE_INTERNAL_EXPECT_FAIL(expr, exception_t, text) \
EXPECT_THROW(expr, exception_t)
#elif defined(__ANDROID__)
// Android asserts do not log anywhere that gtest can currently inspect.
// So we expect exit, but cannot match the message.
#define ABSL_BASE_INTERNAL_EXPECT_FAIL(expr, exception_t, text) \
EXPECT_DEATH(expr, ".*")
#else
#define ABSL_BASE_INTERNAL_EXPECT_FAIL(expr, exception_t, text) \
EXPECT_DEATH_IF_SUPPORTED(expr, text)
#endif
#endif // ABSL_BASE_INTERNAL_EXCEPTION_TESTING_H_

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//
// Copyright 2020 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef ABSL_BASE_INTERNAL_FAST_TYPE_ID_H_
#define ABSL_BASE_INTERNAL_FAST_TYPE_ID_H_
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
template <typename Type>
struct FastTypeTag {
constexpr static char dummy_var = 0;
};
#ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL
template <typename Type>
constexpr char FastTypeTag<Type>::dummy_var;
#endif
// FastTypeId<Type>() evaluates at compile/link-time to a unique pointer for the
// passed-in type. These are meant to be good match for keys into maps or
// straight up comparisons.
using FastTypeIdType = const void*;
template <typename Type>
constexpr inline FastTypeIdType FastTypeId() {
return &FastTypeTag<Type>::dummy_var;
}
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_FAST_TYPE_ID_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_HIDE_PTR_H_
#define ABSL_BASE_INTERNAL_HIDE_PTR_H_
#include <cstdint>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// Arbitrary value with high bits set. Xor'ing with it is unlikely
// to map one valid pointer to another valid pointer.
constexpr uintptr_t HideMask() {
return (uintptr_t{0xF03A5F7BU} << (sizeof(uintptr_t) - 4) * 8) | 0xF03A5F7BU;
}
// Hide a pointer from the leak checker. For internal use only.
// Differs from absl::IgnoreLeak(ptr) in that absl::IgnoreLeak(ptr) causes ptr
// and all objects reachable from ptr to be ignored by the leak checker.
template <class T>
inline uintptr_t HidePtr(T* ptr) {
return reinterpret_cast<uintptr_t>(ptr) ^ HideMask();
}
// Return a pointer that has been hidden from the leak checker.
// For internal use only.
template <class T>
inline T* UnhidePtr(uintptr_t hidden) {
return reinterpret_cast<T*>(hidden ^ HideMask());
}
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_HIDE_PTR_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef ABSL_BASE_INTERNAL_IDENTITY_H_
#define ABSL_BASE_INTERNAL_IDENTITY_H_
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace internal {
template <typename T>
struct identity {
typedef T type;
};
template <typename T>
using identity_t = typename identity<T>::type;
} // namespace internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_IDENTITY_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_INLINE_VARIABLE_H_
#define ABSL_BASE_INTERNAL_INLINE_VARIABLE_H_
#include <type_traits>
#include "absl/base/internal/identity.h"
// File:
// This file define a macro that allows the creation of or emulation of C++17
// inline variables based on whether or not the feature is supported.
////////////////////////////////////////////////////////////////////////////////
// Macro: ABSL_INTERNAL_INLINE_CONSTEXPR(type, name, init)
//
// Description:
// Expands to the equivalent of an inline constexpr instance of the specified
// `type` and `name`, initialized to the value `init`. If the compiler being
// used is detected as supporting actual inline variables as a language
// feature, then the macro expands to an actual inline variable definition.
//
// Requires:
// `type` is a type that is usable in an extern variable declaration.
//
// Requires: `name` is a valid identifier
//
// Requires:
// `init` is an expression that can be used in the following definition:
// constexpr type name = init;
//
// Usage:
//
// // Equivalent to: `inline constexpr size_t variant_npos = -1;`
// ABSL_INTERNAL_INLINE_CONSTEXPR(size_t, variant_npos, -1);
//
// Differences in implementation:
// For a direct, language-level inline variable, decltype(name) will be the
// type that was specified along with const qualification, whereas for
// emulated inline variables, decltype(name) may be different (in practice
// it will likely be a reference type).
////////////////////////////////////////////////////////////////////////////////
#ifdef __cpp_inline_variables
// Clang's -Wmissing-variable-declarations option erroneously warned that
// inline constexpr objects need to be pre-declared. This has now been fixed,
// but we will need to support this workaround for people building with older
// versions of clang.
//
// Bug: https://bugs.llvm.org/show_bug.cgi?id=35862
//
// Note:
// identity_t is used here so that the const and name are in the
// appropriate place for pointer types, reference types, function pointer
// types, etc..
#if defined(__clang__)
#define ABSL_INTERNAL_EXTERN_DECL(type, name) \
extern const ::absl::internal::identity_t<type> name;
#else // Otherwise, just define the macro to do nothing.
#define ABSL_INTERNAL_EXTERN_DECL(type, name)
#endif // defined(__clang__)
// See above comment at top of file for details.
#define ABSL_INTERNAL_INLINE_CONSTEXPR(type, name, init) \
ABSL_INTERNAL_EXTERN_DECL(type, name) \
inline constexpr ::absl::internal::identity_t<type> name = init
#else
// See above comment at top of file for details.
//
// Note:
// identity_t is used here so that the const and name are in the
// appropriate place for pointer types, reference types, function pointer
// types, etc..
#define ABSL_INTERNAL_INLINE_CONSTEXPR(var_type, name, init) \
template <class /*AbslInternalDummy*/ = void> \
struct AbslInternalInlineVariableHolder##name { \
static constexpr ::absl::internal::identity_t<var_type> kInstance = init; \
}; \
\
template <class AbslInternalDummy> \
constexpr ::absl::internal::identity_t<var_type> \
AbslInternalInlineVariableHolder##name<AbslInternalDummy>::kInstance; \
\
static constexpr const ::absl::internal::identity_t<var_type>& \
name = /* NOLINT */ \
AbslInternalInlineVariableHolder##name<>::kInstance; \
static_assert(sizeof(void (*)(decltype(name))) != 0, \
"Silence unused variable warnings.")
#endif // __cpp_inline_variables
#endif // ABSL_BASE_INTERNAL_INLINE_VARIABLE_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_INLINE_VARIABLE_TESTING_H_
#define ABSL_BASE_INTERNAL_INLINE_VARIABLE_TESTING_H_
#include "absl/base/internal/inline_variable.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace inline_variable_testing_internal {
struct Foo {
int value = 5;
};
ABSL_INTERNAL_INLINE_CONSTEXPR(Foo, inline_variable_foo, {});
ABSL_INTERNAL_INLINE_CONSTEXPR(Foo, other_inline_variable_foo, {});
ABSL_INTERNAL_INLINE_CONSTEXPR(int, inline_variable_int, 5);
ABSL_INTERNAL_INLINE_CONSTEXPR(int, other_inline_variable_int, 5);
ABSL_INTERNAL_INLINE_CONSTEXPR(void(*)(), inline_variable_fun_ptr, nullptr);
const Foo& get_foo_a();
const Foo& get_foo_b();
const int& get_int_a();
const int& get_int_b();
} // namespace inline_variable_testing_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_INLINE_VARIABLE_TESTING_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// absl::base_internal::invoke(f, args...) is an implementation of
// INVOKE(f, args...) from section [func.require] of the C++ standard.
// When compiled as C++17 and later versions, it is implemented as an alias of
// std::invoke.
//
// [func.require]
// Define INVOKE (f, t1, t2, ..., tN) as follows:
// 1. (t1.*f)(t2, ..., tN) when f is a pointer to a member function of a class T
// and t1 is an object of type T or a reference to an object of type T or a
// reference to an object of a type derived from T;
// 2. ((*t1).*f)(t2, ..., tN) when f is a pointer to a member function of a
// class T and t1 is not one of the types described in the previous item;
// 3. t1.*f when N == 1 and f is a pointer to member data of a class T and t1 is
// an object of type T or a reference to an object of type T or a reference
// to an object of a type derived from T;
// 4. (*t1).*f when N == 1 and f is a pointer to member data of a class T and t1
// is not one of the types described in the previous item;
// 5. f(t1, t2, ..., tN) in all other cases.
//
// The implementation is SFINAE-friendly: substitution failure within invoke()
// isn't an error.
#ifndef ABSL_BASE_INTERNAL_INVOKE_H_
#define ABSL_BASE_INTERNAL_INVOKE_H_
#include "absl/base/config.h"
#if ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L
#include <functional>
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
using std::invoke;
using std::invoke_result_t;
using std::is_invocable_r;
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#else // ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L
#include <algorithm>
#include <type_traits>
#include <utility>
#include "absl/meta/type_traits.h"
// The following code is internal implementation detail. See the comment at the
// top of this file for the API documentation.
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// The five classes below each implement one of the clauses from the definition
// of INVOKE. The inner class template Accept<F, Args...> checks whether the
// clause is applicable; static function template Invoke(f, args...) does the
// invocation.
//
// By separating the clause selection logic from invocation we make sure that
// Invoke() does exactly what the standard says.
template <typename Derived>
struct StrippedAccept {
template <typename... Args>
struct Accept : Derived::template AcceptImpl<typename std::remove_cv<
typename std::remove_reference<Args>::type>::type...> {};
};
// (t1.*f)(t2, ..., tN) when f is a pointer to a member function of a class T
// and t1 is an object of type T or a reference to an object of type T or a
// reference to an object of a type derived from T.
struct MemFunAndRef : StrippedAccept<MemFunAndRef> {
template <typename... Args>
struct AcceptImpl : std::false_type {};
template <typename MemFunType, typename C, typename Obj, typename... Args>
struct AcceptImpl<MemFunType C::*, Obj, Args...>
: std::integral_constant<bool, std::is_base_of<C, Obj>::value &&
absl::is_function<MemFunType>::value> {
};
template <typename MemFun, typename Obj, typename... Args>
static decltype((std::declval<Obj>().*
std::declval<MemFun>())(std::declval<Args>()...))
Invoke(MemFun&& mem_fun, Obj&& obj, Args&&... args) {
// Ignore bogus GCC warnings on this line.
// See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101436 for similar example.
#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(11, 0)
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Warray-bounds"
#pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
#endif
return (std::forward<Obj>(obj).*
std::forward<MemFun>(mem_fun))(std::forward<Args>(args)...);
#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(11, 0)
#pragma GCC diagnostic pop
#endif
}
};
// ((*t1).*f)(t2, ..., tN) when f is a pointer to a member function of a
// class T and t1 is not one of the types described in the previous item.
struct MemFunAndPtr : StrippedAccept<MemFunAndPtr> {
template <typename... Args>
struct AcceptImpl : std::false_type {};
template <typename MemFunType, typename C, typename Ptr, typename... Args>
struct AcceptImpl<MemFunType C::*, Ptr, Args...>
: std::integral_constant<bool, !std::is_base_of<C, Ptr>::value &&
absl::is_function<MemFunType>::value> {
};
template <typename MemFun, typename Ptr, typename... Args>
static decltype(((*std::declval<Ptr>()).*
std::declval<MemFun>())(std::declval<Args>()...))
Invoke(MemFun&& mem_fun, Ptr&& ptr, Args&&... args) {
return ((*std::forward<Ptr>(ptr)).*
std::forward<MemFun>(mem_fun))(std::forward<Args>(args)...);
}
};
// t1.*f when N == 1 and f is a pointer to member data of a class T and t1 is
// an object of type T or a reference to an object of type T or a reference
// to an object of a type derived from T.
struct DataMemAndRef : StrippedAccept<DataMemAndRef> {
template <typename... Args>
struct AcceptImpl : std::false_type {};
template <typename R, typename C, typename Obj>
struct AcceptImpl<R C::*, Obj>
: std::integral_constant<bool, std::is_base_of<C, Obj>::value &&
!absl::is_function<R>::value> {};
template <typename DataMem, typename Ref>
static decltype(std::declval<Ref>().*std::declval<DataMem>()) Invoke(
DataMem&& data_mem, Ref&& ref) {
return std::forward<Ref>(ref).*std::forward<DataMem>(data_mem);
}
};
// (*t1).*f when N == 1 and f is a pointer to member data of a class T and t1
// is not one of the types described in the previous item.
struct DataMemAndPtr : StrippedAccept<DataMemAndPtr> {
template <typename... Args>
struct AcceptImpl : std::false_type {};
template <typename R, typename C, typename Ptr>
struct AcceptImpl<R C::*, Ptr>
: std::integral_constant<bool, !std::is_base_of<C, Ptr>::value &&
!absl::is_function<R>::value> {};
template <typename DataMem, typename Ptr>
static decltype((*std::declval<Ptr>()).*std::declval<DataMem>()) Invoke(
DataMem&& data_mem, Ptr&& ptr) {
return (*std::forward<Ptr>(ptr)).*std::forward<DataMem>(data_mem);
}
};
// f(t1, t2, ..., tN) in all other cases.
struct Callable {
// Callable doesn't have Accept because it's the last clause that gets picked
// when none of the previous clauses are applicable.
template <typename F, typename... Args>
static decltype(std::declval<F>()(std::declval<Args>()...)) Invoke(
F&& f, Args&&... args) {
return std::forward<F>(f)(std::forward<Args>(args)...);
}
};
// Resolves to the first matching clause.
template <typename... Args>
struct Invoker {
typedef typename std::conditional<
MemFunAndRef::Accept<Args...>::value, MemFunAndRef,
typename std::conditional<
MemFunAndPtr::Accept<Args...>::value, MemFunAndPtr,
typename std::conditional<
DataMemAndRef::Accept<Args...>::value, DataMemAndRef,
typename std::conditional<DataMemAndPtr::Accept<Args...>::value,
DataMemAndPtr, Callable>::type>::type>::
type>::type type;
};
// The result type of Invoke<F, Args...>.
template <typename F, typename... Args>
using invoke_result_t = decltype(Invoker<F, Args...>::type::Invoke(
std::declval<F>(), std::declval<Args>()...));
// Invoke(f, args...) is an implementation of INVOKE(f, args...) from section
// [func.require] of the C++ standard.
template <typename F, typename... Args>
invoke_result_t<F, Args...> invoke(F&& f, Args&&... args) {
return Invoker<F, Args...>::type::Invoke(std::forward<F>(f),
std::forward<Args>(args)...);
}
template <typename AlwaysVoid, typename, typename, typename...>
struct IsInvocableRImpl : std::false_type {};
template <typename R, typename F, typename... Args>
struct IsInvocableRImpl<
absl::void_t<absl::base_internal::invoke_result_t<F, Args...> >, R, F,
Args...>
: std::integral_constant<
bool,
std::is_convertible<absl::base_internal::invoke_result_t<F, Args...>,
R>::value ||
std::is_void<R>::value> {};
// Type trait whose member `value` is true if invoking `F` with `Args` is valid,
// and either the return type is convertible to `R`, or `R` is void.
// C++11-compatible version of `std::is_invocable_r`.
template <typename R, typename F, typename... Args>
using is_invocable_r = IsInvocableRImpl<void, R, F, Args...>;
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L
#endif // ABSL_BASE_INTERNAL_INVOKE_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef ABSL_BASE_INTERNAL_LOW_LEVEL_ALLOC_H_
#define ABSL_BASE_INTERNAL_LOW_LEVEL_ALLOC_H_
// A simple thread-safe memory allocator that does not depend on
// mutexes or thread-specific data. It is intended to be used
// sparingly, and only when malloc() would introduce an unwanted
// dependency, such as inside the heap-checker, or the Mutex
// implementation.
// IWYU pragma: private, include "base/low_level_alloc.h"
#include <sys/types.h>
#include <cstdint>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
// LowLevelAlloc requires that the platform support low-level
// allocation of virtual memory. Platforms lacking this cannot use
// LowLevelAlloc.
#ifdef ABSL_LOW_LEVEL_ALLOC_MISSING
#error ABSL_LOW_LEVEL_ALLOC_MISSING cannot be directly set
#elif !defined(ABSL_HAVE_MMAP) && !defined(_WIN32)
#define ABSL_LOW_LEVEL_ALLOC_MISSING 1
#endif
// Using LowLevelAlloc with kAsyncSignalSafe isn't supported on Windows or
// asm.js / WebAssembly.
// See https://kripken.github.io/emscripten-site/docs/porting/pthreads.html
// for more information.
#ifdef ABSL_LOW_LEVEL_ALLOC_ASYNC_SIGNAL_SAFE_MISSING
#error ABSL_LOW_LEVEL_ALLOC_ASYNC_SIGNAL_SAFE_MISSING cannot be directly set
#elif defined(_WIN32) || defined(__asmjs__) || defined(__wasm__) || \
defined(__hexagon__)
#define ABSL_LOW_LEVEL_ALLOC_ASYNC_SIGNAL_SAFE_MISSING 1
#endif
#include <cstddef>
#include "absl/base/port.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
class LowLevelAlloc {
public:
struct Arena; // an arena from which memory may be allocated
// Returns a pointer to a block of at least "request" bytes
// that have been newly allocated from the specific arena.
// for Alloc() call the DefaultArena() is used.
// Returns 0 if passed request==0.
// Does not return 0 under other circumstances; it crashes if memory
// is not available.
static void *Alloc(size_t request) ABSL_ATTRIBUTE_SECTION(malloc_hook);
static void *AllocWithArena(size_t request, Arena *arena)
ABSL_ATTRIBUTE_SECTION(malloc_hook);
// Deallocates a region of memory that was previously allocated with
// Alloc(). Does nothing if passed 0. "s" must be either 0,
// or must have been returned from a call to Alloc() and not yet passed to
// Free() since that call to Alloc(). The space is returned to the arena
// from which it was allocated.
static void Free(void *s) ABSL_ATTRIBUTE_SECTION(malloc_hook);
// ABSL_ATTRIBUTE_SECTION(malloc_hook) for Alloc* and Free
// are to put all callers of MallocHook::Invoke* in this module
// into special section,
// so that MallocHook::GetCallerStackTrace can function accurately.
// Create a new arena.
// The root metadata for the new arena is allocated in the
// meta_data_arena; the DefaultArena() can be passed for meta_data_arena.
// These values may be ored into flags:
enum {
// Report calls to Alloc() and Free() via the MallocHook interface.
// Set in the DefaultArena.
kCallMallocHook = 0x0001,
#ifndef ABSL_LOW_LEVEL_ALLOC_ASYNC_SIGNAL_SAFE_MISSING
// Make calls to Alloc(), Free() be async-signal-safe. Not set in
// DefaultArena(). Not supported on all platforms.
kAsyncSignalSafe = 0x0002,
#endif
};
// Construct a new arena. The allocation of the underlying metadata honors
// the provided flags. For example, the call NewArena(kAsyncSignalSafe)
// is itself async-signal-safe, as well as generatating an arena that provides
// async-signal-safe Alloc/Free.
static Arena *NewArena(uint32_t flags);
// Destroys an arena allocated by NewArena and returns true,
// provided no allocated blocks remain in the arena.
// If allocated blocks remain in the arena, does nothing and
// returns false.
// It is illegal to attempt to destroy the DefaultArena().
static bool DeleteArena(Arena *arena);
// The default arena that always exists.
static Arena *DefaultArena();
private:
LowLevelAlloc(); // no instances
};
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_LOW_LEVEL_ALLOC_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Core interfaces and definitions used by by low-level interfaces such as
// SpinLock.
#ifndef ABSL_BASE_INTERNAL_LOW_LEVEL_SCHEDULING_H_
#define ABSL_BASE_INTERNAL_LOW_LEVEL_SCHEDULING_H_
#include "absl/base/internal/raw_logging.h"
#include "absl/base/internal/scheduling_mode.h"
#include "absl/base/macros.h"
// The following two declarations exist so SchedulingGuard may friend them with
// the appropriate language linkage. These callbacks allow libc internals, such
// as function level statics, to schedule cooperatively when locking.
extern "C" bool __google_disable_rescheduling(void);
extern "C" void __google_enable_rescheduling(bool disable_result);
namespace absl {
ABSL_NAMESPACE_BEGIN
class CondVar;
class Mutex;
namespace synchronization_internal {
int MutexDelay(int32_t c, int mode);
} // namespace synchronization_internal
namespace base_internal {
class SchedulingHelper; // To allow use of SchedulingGuard.
class SpinLock; // To allow use of SchedulingGuard.
// SchedulingGuard
// Provides guard semantics that may be used to disable cooperative rescheduling
// of the calling thread within specific program blocks. This is used to
// protect resources (e.g. low-level SpinLocks or Domain code) that cooperative
// scheduling depends on.
//
// Domain implementations capable of rescheduling in reaction to involuntary
// kernel thread actions (e.g blocking due to a pagefault or syscall) must
// guarantee that an annotated thread is not allowed to (cooperatively)
// reschedule until the annotated region is complete.
//
// It is an error to attempt to use a cooperatively scheduled resource (e.g.
// Mutex) within a rescheduling-disabled region.
//
// All methods are async-signal safe.
class SchedulingGuard {
public:
// Returns true iff the calling thread may be cooperatively rescheduled.
static bool ReschedulingIsAllowed();
SchedulingGuard(const SchedulingGuard&) = delete;
SchedulingGuard& operator=(const SchedulingGuard&) = delete;
private:
// Disable cooperative rescheduling of the calling thread. It may still
// initiate scheduling operations (e.g. wake-ups), however, it may not itself
// reschedule. Nestable. The returned result is opaque, clients should not
// attempt to interpret it.
// REQUIRES: Result must be passed to a pairing EnableScheduling().
static bool DisableRescheduling();
// Marks the end of a rescheduling disabled region, previously started by
// DisableRescheduling().
// REQUIRES: Pairs with innermost call (and result) of DisableRescheduling().
static void EnableRescheduling(bool disable_result);
// A scoped helper for {Disable, Enable}Rescheduling().
// REQUIRES: destructor must run in same thread as constructor.
struct ScopedDisable {
ScopedDisable() { disabled = SchedulingGuard::DisableRescheduling(); }
~ScopedDisable() { SchedulingGuard::EnableRescheduling(disabled); }
bool disabled;
};
// A scoped helper to enable rescheduling temporarily.
// REQUIRES: destructor must run in same thread as constructor.
class ScopedEnable {
public:
ScopedEnable();
~ScopedEnable();
private:
int scheduling_disabled_depth_;
};
// Access to SchedulingGuard is explicitly permitted.
friend class absl::CondVar;
friend class absl::Mutex;
friend class SchedulingHelper;
friend class SpinLock;
friend int absl::synchronization_internal::MutexDelay(int32_t c, int mode);
};
//------------------------------------------------------------------------------
// End of public interfaces.
//------------------------------------------------------------------------------
inline bool SchedulingGuard::ReschedulingIsAllowed() {
return false;
}
inline bool SchedulingGuard::DisableRescheduling() {
return false;
}
inline void SchedulingGuard::EnableRescheduling(bool /* disable_result */) {
return;
}
inline SchedulingGuard::ScopedEnable::ScopedEnable()
: scheduling_disabled_depth_(0) {}
inline SchedulingGuard::ScopedEnable::~ScopedEnable() {
ABSL_RAW_CHECK(scheduling_disabled_depth_ == 0, "disable unused warning");
}
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_LOW_LEVEL_SCHEDULING_H_

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// Copyright 2023 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_NULLABILITY_IMPL_H_
#define ABSL_BASE_INTERNAL_NULLABILITY_IMPL_H_
#include <memory>
#include <type_traits>
#include "absl/base/attributes.h"
#include "absl/meta/type_traits.h"
namespace absl {
namespace nullability_internal {
// `IsNullabilityCompatible` checks whether its first argument is a class
// explicitly tagged as supporting nullability annotations. The tag is the type
// declaration `absl_nullability_compatible`.
template <typename, typename = void>
struct IsNullabilityCompatible : std::false_type {};
template <typename T>
struct IsNullabilityCompatible<
T, absl::void_t<typename T::absl_nullability_compatible>> : std::true_type {
};
template <typename T>
constexpr bool IsSupportedType = IsNullabilityCompatible<T>::value;
template <typename T>
constexpr bool IsSupportedType<T*> = true;
template <typename T, typename U>
constexpr bool IsSupportedType<T U::*> = true;
template <typename T, typename... Deleter>
constexpr bool IsSupportedType<std::unique_ptr<T, Deleter...>> = true;
template <typename T>
constexpr bool IsSupportedType<std::shared_ptr<T>> = true;
template <typename T>
struct EnableNullable {
static_assert(nullability_internal::IsSupportedType<std::remove_cv_t<T>>,
"Template argument must be a raw or supported smart pointer "
"type. See absl/base/nullability.h.");
using type = T;
};
template <typename T>
struct EnableNonnull {
static_assert(nullability_internal::IsSupportedType<std::remove_cv_t<T>>,
"Template argument must be a raw or supported smart pointer "
"type. See absl/base/nullability.h.");
using type = T;
};
template <typename T>
struct EnableNullabilityUnknown {
static_assert(nullability_internal::IsSupportedType<std::remove_cv_t<T>>,
"Template argument must be a raw or supported smart pointer "
"type. See absl/base/nullability.h.");
using type = T;
};
// Note: we do not apply Clang nullability attributes (e.g. _Nullable). These
// only support raw pointers, and conditionally enabling them only for raw
// pointers inhibits template arg deduction. Ideally, they would support all
// pointer-like types.
template <typename T, typename = typename EnableNullable<T>::type>
using NullableImpl
#if ABSL_HAVE_CPP_ATTRIBUTE(clang::annotate)
[[clang::annotate("Nullable")]]
#endif
= T;
template <typename T, typename = typename EnableNonnull<T>::type>
using NonnullImpl
#if ABSL_HAVE_CPP_ATTRIBUTE(clang::annotate)
[[clang::annotate("Nonnull")]]
#endif
= T;
template <typename T, typename = typename EnableNullabilityUnknown<T>::type>
using NullabilityUnknownImpl
#if ABSL_HAVE_CPP_ATTRIBUTE(clang::annotate)
[[clang::annotate("Nullability_Unspecified")]]
#endif
= T;
} // namespace nullability_internal
} // namespace absl
#endif // ABSL_BASE_INTERNAL_NULLABILITY_IMPL_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_PER_THREAD_TLS_H_
#define ABSL_BASE_INTERNAL_PER_THREAD_TLS_H_
// This header defines two macros:
//
// If the platform supports thread-local storage:
//
// * ABSL_PER_THREAD_TLS_KEYWORD is the C keyword needed to declare a
// thread-local variable
// * ABSL_PER_THREAD_TLS is 1
//
// Otherwise:
//
// * ABSL_PER_THREAD_TLS_KEYWORD is empty
// * ABSL_PER_THREAD_TLS is 0
//
// Microsoft C supports thread-local storage.
// GCC supports it if the appropriate version of glibc is available,
// which the programmer can indicate by defining ABSL_HAVE_TLS
#include "absl/base/port.h" // For ABSL_HAVE_TLS
#if defined(ABSL_PER_THREAD_TLS)
#error ABSL_PER_THREAD_TLS cannot be directly set
#elif defined(ABSL_PER_THREAD_TLS_KEYWORD)
#error ABSL_PER_THREAD_TLS_KEYWORD cannot be directly set
#elif defined(ABSL_HAVE_TLS)
#define ABSL_PER_THREAD_TLS_KEYWORD __thread
#define ABSL_PER_THREAD_TLS 1
#elif defined(_MSC_VER)
#define ABSL_PER_THREAD_TLS_KEYWORD __declspec(thread)
#define ABSL_PER_THREAD_TLS 1
#else
#define ABSL_PER_THREAD_TLS_KEYWORD
#define ABSL_PER_THREAD_TLS 0
#endif
#endif // ABSL_BASE_INTERNAL_PER_THREAD_TLS_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_PRETTY_FUNCTION_H_
#define ABSL_BASE_INTERNAL_PRETTY_FUNCTION_H_
// ABSL_PRETTY_FUNCTION
//
// In C++11, __func__ gives the undecorated name of the current function. That
// is, "main", not "int main()". Various compilers give extra macros to get the
// decorated function name, including return type and arguments, to
// differentiate between overload sets. ABSL_PRETTY_FUNCTION is a portable
// version of these macros which forwards to the correct macro on each compiler.
#if defined(_MSC_VER)
#define ABSL_PRETTY_FUNCTION __FUNCSIG__
#elif defined(__GNUC__)
#define ABSL_PRETTY_FUNCTION __PRETTY_FUNCTION__
#else
#error "Unsupported compiler"
#endif
#endif // ABSL_BASE_INTERNAL_PRETTY_FUNCTION_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Thread-safe logging routines that do not allocate any memory or
// acquire any locks, and can therefore be used by low-level memory
// allocation, synchronization, and signal-handling code.
#ifndef ABSL_BASE_INTERNAL_RAW_LOGGING_H_
#define ABSL_BASE_INTERNAL_RAW_LOGGING_H_
#include <string>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#include "absl/base/internal/atomic_hook.h"
#include "absl/base/log_severity.h"
#include "absl/base/macros.h"
#include "absl/base/optimization.h"
#include "absl/base/port.h"
// This is similar to LOG(severity) << format..., but
// * it is to be used ONLY by low-level modules that can't use normal LOG()
// * it is designed to be a low-level logger that does not allocate any
// memory and does not need any locks, hence:
// * it logs straight and ONLY to STDERR w/o buffering
// * it uses an explicit printf-format and arguments list
// * it will silently chop off really long message strings
// Usage example:
// ABSL_RAW_LOG(ERROR, "Failed foo with %i: %s", status, error);
// This will print an almost standard log line like this to stderr only:
// E0821 211317 file.cc:123] RAW: Failed foo with 22: bad_file
#define ABSL_RAW_LOG(severity, ...) \
do { \
constexpr const char* absl_raw_log_internal_basename = \
::absl::raw_log_internal::Basename(__FILE__, sizeof(__FILE__) - 1); \
::absl::raw_log_internal::RawLog(ABSL_RAW_LOG_INTERNAL_##severity, \
absl_raw_log_internal_basename, __LINE__, \
__VA_ARGS__); \
ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_##severity; \
} while (0)
// Similar to CHECK(condition) << message, but for low-level modules:
// we use only ABSL_RAW_LOG that does not allocate memory.
// We do not want to provide args list here to encourage this usage:
// if (!cond) ABSL_RAW_LOG(FATAL, "foo ...", hard_to_compute_args);
// so that the args are not computed when not needed.
#define ABSL_RAW_CHECK(condition, message) \
do { \
if (ABSL_PREDICT_FALSE(!(condition))) { \
ABSL_RAW_LOG(FATAL, "Check %s failed: %s", #condition, message); \
} \
} while (0)
// ABSL_INTERNAL_LOG and ABSL_INTERNAL_CHECK work like the RAW variants above,
// except that if the richer log library is linked into the binary, we dispatch
// to that instead. This is potentially useful for internal logging and
// assertions, where we are using RAW_LOG neither for its async-signal-safety
// nor for its non-allocating nature, but rather because raw logging has very
// few other dependencies.
//
// The API is a subset of the above: each macro only takes two arguments. Use
// StrCat if you need to build a richer message.
#define ABSL_INTERNAL_LOG(severity, message) \
do { \
constexpr const char* absl_raw_log_internal_filename = __FILE__; \
::absl::raw_log_internal::internal_log_function( \
ABSL_RAW_LOG_INTERNAL_##severity, absl_raw_log_internal_filename, \
__LINE__, message); \
ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_##severity; \
} while (0)
#define ABSL_INTERNAL_CHECK(condition, message) \
do { \
if (ABSL_PREDICT_FALSE(!(condition))) { \
std::string death_message = "Check " #condition " failed: "; \
death_message += std::string(message); \
ABSL_INTERNAL_LOG(FATAL, death_message); \
} \
} while (0)
#ifndef NDEBUG
#define ABSL_RAW_DLOG(severity, ...) ABSL_RAW_LOG(severity, __VA_ARGS__)
#define ABSL_RAW_DCHECK(condition, message) ABSL_RAW_CHECK(condition, message)
#else // NDEBUG
#define ABSL_RAW_DLOG(severity, ...) \
while (false) ABSL_RAW_LOG(severity, __VA_ARGS__)
#define ABSL_RAW_DCHECK(condition, message) \
while (false) ABSL_RAW_CHECK(condition, message)
#endif // NDEBUG
#define ABSL_RAW_LOG_INTERNAL_INFO ::absl::LogSeverity::kInfo
#define ABSL_RAW_LOG_INTERNAL_WARNING ::absl::LogSeverity::kWarning
#define ABSL_RAW_LOG_INTERNAL_ERROR ::absl::LogSeverity::kError
#define ABSL_RAW_LOG_INTERNAL_FATAL ::absl::LogSeverity::kFatal
#define ABSL_RAW_LOG_INTERNAL_LEVEL(severity) \
::absl::NormalizeLogSeverity(severity)
#define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_INFO
#define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_WARNING
#define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_ERROR
#define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_FATAL ABSL_UNREACHABLE()
#define ABSL_RAW_LOG_INTERNAL_MAYBE_UNREACHABLE_LEVEL(severity)
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace raw_log_internal {
// Helper function to implement ABSL_RAW_LOG
// Logs format... at "severity" level, reporting it
// as called from file:line.
// This does not allocate memory or acquire locks.
void RawLog(absl::LogSeverity severity, const char* file, int line,
const char* format, ...) ABSL_PRINTF_ATTRIBUTE(4, 5);
// Writes the provided buffer directly to stderr, in a signal-safe, low-level
// manner. Preserves errno.
void AsyncSignalSafeWriteError(const char* s, size_t len);
// compile-time function to get the "base" filename, that is, the part of
// a filename after the last "/" or "\" path separator. The search starts at
// the end of the string; the second parameter is the length of the string.
constexpr const char* Basename(const char* fname, int offset) {
return offset == 0 || fname[offset - 1] == '/' || fname[offset - 1] == '\\'
? fname + offset
: Basename(fname, offset - 1);
}
// For testing only.
// Returns true if raw logging is fully supported. When it is not
// fully supported, no messages will be emitted, but a log at FATAL
// severity will cause an abort.
//
// TODO(gfalcon): Come up with a better name for this method.
bool RawLoggingFullySupported();
// Function type for a raw_log customization hook for suppressing messages
// by severity, and for writing custom prefixes on non-suppressed messages.
//
// The installed hook is called for every raw log invocation. The message will
// be logged to stderr only if the hook returns true. FATAL errors will cause
// the process to abort, even if writing to stderr is suppressed. The hook is
// also provided with an output buffer, where it can write a custom log message
// prefix.
//
// The raw_log system does not allocate memory or grab locks. User-provided
// hooks must avoid these operations, and must not throw exceptions.
//
// 'severity' is the severity level of the message being written.
// 'file' and 'line' are the file and line number where the ABSL_RAW_LOG macro
// was located.
// 'buf' and 'buf_size' are pointers to the buffer and buffer size. If the
// hook writes a prefix, it must increment *buf and decrement *buf_size
// accordingly.
using LogFilterAndPrefixHook = bool (*)(absl::LogSeverity severity,
const char* file, int line, char** buf,
int* buf_size);
// Function type for a raw_log customization hook called to abort a process
// when a FATAL message is logged. If the provided AbortHook() returns, the
// logging system will call abort().
//
// 'file' and 'line' are the file and line number where the ABSL_RAW_LOG macro
// was located.
// The NUL-terminated logged message lives in the buffer between 'buf_start'
// and 'buf_end'. 'prefix_end' points to the first non-prefix character of the
// buffer (as written by the LogFilterAndPrefixHook.)
//
// The lifetime of the filename and message buffers will not end while the
// process remains alive.
using AbortHook = void (*)(const char* file, int line, const char* buf_start,
const char* prefix_end, const char* buf_end);
// Internal logging function for ABSL_INTERNAL_LOG to dispatch to.
//
// TODO(gfalcon): When string_view no longer depends on base, change this
// interface to take its message as a string_view instead.
using InternalLogFunction = void (*)(absl::LogSeverity severity,
const char* file, int line,
const std::string& message);
ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_DLL extern base_internal::AtomicHook<
InternalLogFunction>
internal_log_function;
// Registers hooks of the above types. Only a single hook of each type may be
// registered. It is an error to call these functions multiple times with
// different input arguments.
//
// These functions are safe to call at any point during initialization; they do
// not block or malloc, and are async-signal safe.
void RegisterLogFilterAndPrefixHook(LogFilterAndPrefixHook func);
void RegisterAbortHook(AbortHook func);
void RegisterInternalLogFunction(InternalLogFunction func);
} // namespace raw_log_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_RAW_LOGGING_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Core interfaces and definitions used by by low-level interfaces such as
// SpinLock.
#ifndef ABSL_BASE_INTERNAL_SCHEDULING_MODE_H_
#define ABSL_BASE_INTERNAL_SCHEDULING_MODE_H_
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// Used to describe how a thread may be scheduled. Typically associated with
// the declaration of a resource supporting synchronized access.
//
// SCHEDULE_COOPERATIVE_AND_KERNEL:
// Specifies that when waiting, a cooperative thread (e.g. a Fiber) may
// reschedule (using base::scheduling semantics); allowing other cooperative
// threads to proceed.
//
// SCHEDULE_KERNEL_ONLY: (Also described as "non-cooperative")
// Specifies that no cooperative scheduling semantics may be used, even if the
// current thread is itself cooperatively scheduled. This means that
// cooperative threads will NOT allow other cooperative threads to execute in
// their place while waiting for a resource of this type. Host operating system
// semantics (e.g. a futex) may still be used.
//
// When optional, clients should strongly prefer SCHEDULE_COOPERATIVE_AND_KERNEL
// by default. SCHEDULE_KERNEL_ONLY should only be used for resources on which
// base::scheduling (e.g. the implementation of a Scheduler) may depend.
//
// NOTE: Cooperative resources may not be nested below non-cooperative ones.
// This means that it is invalid to to acquire a SCHEDULE_COOPERATIVE_AND_KERNEL
// resource if a SCHEDULE_KERNEL_ONLY resource is already held.
enum SchedulingMode {
SCHEDULE_KERNEL_ONLY = 0, // Allow scheduling only the host OS.
SCHEDULE_COOPERATIVE_AND_KERNEL, // Also allow cooperative scheduling.
};
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_SCHEDULING_MODE_H_

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//
// Copyright 2019 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef ABSL_BASE_INTERNAL_SCOPED_SET_ENV_H_
#define ABSL_BASE_INTERNAL_SCOPED_SET_ENV_H_
#include <string>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
class ScopedSetEnv {
public:
ScopedSetEnv(const char* var_name, const char* new_value);
~ScopedSetEnv();
private:
std::string var_name_;
std::string old_value_;
// True if the environment variable was initially not set.
bool was_unset_;
};
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_SCOPED_SET_ENV_H_

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//
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Most users requiring mutual exclusion should use Mutex.
// SpinLock is provided for use in two situations:
// - for use by Abseil internal code that Mutex itself depends on
// - for async signal safety (see below)
// SpinLock with a base_internal::SchedulingMode::SCHEDULE_KERNEL_ONLY is async
// signal safe. If a spinlock is used within a signal handler, all code that
// acquires the lock must ensure that the signal cannot arrive while they are
// holding the lock. Typically, this is done by blocking the signal.
//
// Threads waiting on a SpinLock may be woken in an arbitrary order.
#ifndef ABSL_BASE_INTERNAL_SPINLOCK_H_
#define ABSL_BASE_INTERNAL_SPINLOCK_H_
#include <atomic>
#include <cstdint>
#include "absl/base/attributes.h"
#include "absl/base/const_init.h"
#include "absl/base/dynamic_annotations.h"
#include "absl/base/internal/low_level_scheduling.h"
#include "absl/base/internal/raw_logging.h"
#include "absl/base/internal/scheduling_mode.h"
#include "absl/base/internal/tsan_mutex_interface.h"
#include "absl/base/thread_annotations.h"
namespace tcmalloc {
namespace tcmalloc_internal {
class AllocationGuardSpinLockHolder;
} // namespace tcmalloc_internal
} // namespace tcmalloc
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
class ABSL_LOCKABLE SpinLock {
public:
SpinLock() : lockword_(kSpinLockCooperative) {
ABSL_TSAN_MUTEX_CREATE(this, __tsan_mutex_not_static);
}
// Constructors that allow non-cooperative spinlocks to be created for use
// inside thread schedulers. Normal clients should not use these.
explicit SpinLock(base_internal::SchedulingMode mode);
// Constructor for global SpinLock instances. See absl/base/const_init.h.
constexpr SpinLock(absl::ConstInitType, base_internal::SchedulingMode mode)
: lockword_(IsCooperative(mode) ? kSpinLockCooperative : 0) {}
// For global SpinLock instances prefer trivial destructor when possible.
// Default but non-trivial destructor in some build configurations causes an
// extra static initializer.
#ifdef ABSL_INTERNAL_HAVE_TSAN_INTERFACE
~SpinLock() { ABSL_TSAN_MUTEX_DESTROY(this, __tsan_mutex_not_static); }
#else
~SpinLock() = default;
#endif
// Acquire this SpinLock.
inline void Lock() ABSL_EXCLUSIVE_LOCK_FUNCTION() {
ABSL_TSAN_MUTEX_PRE_LOCK(this, 0);
if (!TryLockImpl()) {
SlowLock();
}
ABSL_TSAN_MUTEX_POST_LOCK(this, 0, 0);
}
// Try to acquire this SpinLock without blocking and return true if the
// acquisition was successful. If the lock was not acquired, false is
// returned. If this SpinLock is free at the time of the call, TryLock
// will return true with high probability.
inline bool TryLock() ABSL_EXCLUSIVE_TRYLOCK_FUNCTION(true) {
ABSL_TSAN_MUTEX_PRE_LOCK(this, __tsan_mutex_try_lock);
bool res = TryLockImpl();
ABSL_TSAN_MUTEX_POST_LOCK(
this, __tsan_mutex_try_lock | (res ? 0 : __tsan_mutex_try_lock_failed),
0);
return res;
}
// Release this SpinLock, which must be held by the calling thread.
inline void Unlock() ABSL_UNLOCK_FUNCTION() {
ABSL_TSAN_MUTEX_PRE_UNLOCK(this, 0);
uint32_t lock_value = lockword_.load(std::memory_order_relaxed);
lock_value = lockword_.exchange(lock_value & kSpinLockCooperative,
std::memory_order_release);
if ((lock_value & kSpinLockDisabledScheduling) != 0) {
base_internal::SchedulingGuard::EnableRescheduling(true);
}
if ((lock_value & kWaitTimeMask) != 0) {
// Collect contentionz profile info, and speed the wakeup of any waiter.
// The wait_cycles value indicates how long this thread spent waiting
// for the lock.
SlowUnlock(lock_value);
}
ABSL_TSAN_MUTEX_POST_UNLOCK(this, 0);
}
// Determine if the lock is held. When the lock is held by the invoking
// thread, true will always be returned. Intended to be used as
// CHECK(lock.IsHeld()).
inline bool IsHeld() const {
return (lockword_.load(std::memory_order_relaxed) & kSpinLockHeld) != 0;
}
// Return immediately if this thread holds the SpinLock exclusively.
// Otherwise, report an error by crashing with a diagnostic.
inline void AssertHeld() const ABSL_ASSERT_EXCLUSIVE_LOCK() {
if (!IsHeld()) {
ABSL_RAW_LOG(FATAL, "thread should hold the lock on SpinLock");
}
}
protected:
// These should not be exported except for testing.
// Store number of cycles between wait_start_time and wait_end_time in a
// lock value.
static uint32_t EncodeWaitCycles(int64_t wait_start_time,
int64_t wait_end_time);
// Extract number of wait cycles in a lock value.
static int64_t DecodeWaitCycles(uint32_t lock_value);
// Provide access to protected method above. Use for testing only.
friend struct SpinLockTest;
friend class tcmalloc::tcmalloc_internal::AllocationGuardSpinLockHolder;
private:
// lockword_ is used to store the following:
//
// bit[0] encodes whether a lock is being held.
// bit[1] encodes whether a lock uses cooperative scheduling.
// bit[2] encodes whether the current lock holder disabled scheduling when
// acquiring the lock. Only set when kSpinLockHeld is also set.
// bit[3:31] encodes time a lock spent on waiting as a 29-bit unsigned int.
// This is set by the lock holder to indicate how long it waited on
// the lock before eventually acquiring it. The number of cycles is
// encoded as a 29-bit unsigned int, or in the case that the current
// holder did not wait but another waiter is queued, the LSB
// (kSpinLockSleeper) is set. The implementation does not explicitly
// track the number of queued waiters beyond this. It must always be
// assumed that waiters may exist if the current holder was required to
// queue.
//
// Invariant: if the lock is not held, the value is either 0 or
// kSpinLockCooperative.
static constexpr uint32_t kSpinLockHeld = 1;
static constexpr uint32_t kSpinLockCooperative = 2;
static constexpr uint32_t kSpinLockDisabledScheduling = 4;
static constexpr uint32_t kSpinLockSleeper = 8;
// Includes kSpinLockSleeper.
static constexpr uint32_t kWaitTimeMask =
~(kSpinLockHeld | kSpinLockCooperative | kSpinLockDisabledScheduling);
// Returns true if the provided scheduling mode is cooperative.
static constexpr bool IsCooperative(
base_internal::SchedulingMode scheduling_mode) {
return scheduling_mode == base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL;
}
bool IsCooperative() const {
return lockword_.load(std::memory_order_relaxed) & kSpinLockCooperative;
}
uint32_t TryLockInternal(uint32_t lock_value, uint32_t wait_cycles);
void SlowLock() ABSL_ATTRIBUTE_COLD;
void SlowUnlock(uint32_t lock_value) ABSL_ATTRIBUTE_COLD;
uint32_t SpinLoop();
inline bool TryLockImpl() {
uint32_t lock_value = lockword_.load(std::memory_order_relaxed);
return (TryLockInternal(lock_value, 0) & kSpinLockHeld) == 0;
}
std::atomic<uint32_t> lockword_;
SpinLock(const SpinLock&) = delete;
SpinLock& operator=(const SpinLock&) = delete;
};
// Corresponding locker object that arranges to acquire a spinlock for
// the duration of a C++ scope.
class ABSL_SCOPED_LOCKABLE SpinLockHolder {
public:
inline explicit SpinLockHolder(SpinLock* l) ABSL_EXCLUSIVE_LOCK_FUNCTION(l)
: lock_(l) {
l->Lock();
}
inline ~SpinLockHolder() ABSL_UNLOCK_FUNCTION() { lock_->Unlock(); }
SpinLockHolder(const SpinLockHolder&) = delete;
SpinLockHolder& operator=(const SpinLockHolder&) = delete;
private:
SpinLock* lock_;
};
// Register a hook for profiling support.
//
// The function pointer registered here will be called whenever a spinlock is
// contended. The callback is given an opaque handle to the contended spinlock
// and the number of wait cycles. This is thread-safe, but only a single
// profiler can be registered. It is an error to call this function multiple
// times with different arguments.
void RegisterSpinLockProfiler(void (*fn)(const void* lock,
int64_t wait_cycles));
//------------------------------------------------------------------------------
// Public interface ends here.
//------------------------------------------------------------------------------
// If (result & kSpinLockHeld) == 0, then *this was successfully locked.
// Otherwise, returns last observed value for lockword_.
inline uint32_t SpinLock::TryLockInternal(uint32_t lock_value,
uint32_t wait_cycles) {
if ((lock_value & kSpinLockHeld) != 0) {
return lock_value;
}
uint32_t sched_disabled_bit = 0;
if ((lock_value & kSpinLockCooperative) == 0) {
// For non-cooperative locks we must make sure we mark ourselves as
// non-reschedulable before we attempt to CompareAndSwap.
if (base_internal::SchedulingGuard::DisableRescheduling()) {
sched_disabled_bit = kSpinLockDisabledScheduling;
}
}
if (!lockword_.compare_exchange_strong(
lock_value,
kSpinLockHeld | lock_value | wait_cycles | sched_disabled_bit,
std::memory_order_acquire, std::memory_order_relaxed)) {
base_internal::SchedulingGuard::EnableRescheduling(sched_disabled_bit != 0);
}
return lock_value;
}
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_SPINLOCK_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// This file is an Akaros-specific part of spinlock_wait.cc
#include <atomic>
#include "absl/base/internal/scheduling_mode.h"
extern "C" {
ABSL_ATTRIBUTE_WEAK void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockDelay)(
std::atomic<uint32_t>* /* lock_word */, uint32_t /* value */,
int /* loop */, absl::base_internal::SchedulingMode /* mode */) {
// In Akaros, one must take care not to call anything that could cause a
// malloc(), a blocking system call, or a uthread_yield() while holding a
// spinlock. Our callers assume will not call into libraries or other
// arbitrary code.
}
ABSL_ATTRIBUTE_WEAK void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockWake)(
std::atomic<uint32_t>* /* lock_word */, bool /* all */) {}
} // extern "C"

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// This file is a Linux-specific part of spinlock_wait.cc
#include <linux/futex.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <atomic>
#include <climits>
#include <cstdint>
#include <ctime>
#include "absl/base/attributes.h"
#include "absl/base/internal/errno_saver.h"
// The SpinLock lockword is `std::atomic<uint32_t>`. Here we assert that
// `std::atomic<uint32_t>` is bitwise equivalent of the `int` expected
// by SYS_futex. We also assume that reads/writes done to the lockword
// by SYS_futex have rational semantics with regard to the
// std::atomic<> API. C++ provides no guarantees of these assumptions,
// but they are believed to hold in practice.
static_assert(sizeof(std::atomic<uint32_t>) == sizeof(int),
"SpinLock lockword has the wrong size for a futex");
// Some Android headers are missing these definitions even though they
// support these futex operations.
#ifdef __BIONIC__
#ifndef SYS_futex
#define SYS_futex __NR_futex
#endif
#ifndef FUTEX_PRIVATE_FLAG
#define FUTEX_PRIVATE_FLAG 128
#endif
#endif
#if defined(__NR_futex_time64) && !defined(SYS_futex_time64)
#define SYS_futex_time64 __NR_futex_time64
#endif
#if defined(SYS_futex_time64) && !defined(SYS_futex)
#define SYS_futex SYS_futex_time64
#endif
extern "C" {
ABSL_ATTRIBUTE_WEAK void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockDelay)(
std::atomic<uint32_t> *w, uint32_t value, int,
absl::base_internal::SchedulingMode) {
absl::base_internal::ErrnoSaver errno_saver;
syscall(SYS_futex, w, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, value, nullptr);
}
ABSL_ATTRIBUTE_WEAK void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockWake)(
std::atomic<uint32_t> *w, bool all) {
syscall(SYS_futex, w, FUTEX_WAKE | FUTEX_PRIVATE_FLAG, all ? INT_MAX : 1, 0);
}
} // extern "C"

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// This file is a Posix-specific part of spinlock_wait.cc
#include <sched.h>
#include <atomic>
#include <ctime>
#include "absl/base/internal/errno_saver.h"
#include "absl/base/internal/scheduling_mode.h"
#include "absl/base/port.h"
extern "C" {
ABSL_ATTRIBUTE_WEAK void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockDelay)(
std::atomic<uint32_t>* /* lock_word */, uint32_t /* value */, int loop,
absl::base_internal::SchedulingMode /* mode */) {
absl::base_internal::ErrnoSaver errno_saver;
if (loop == 0) {
} else if (loop == 1) {
sched_yield();
} else {
struct timespec tm;
tm.tv_sec = 0;
tm.tv_nsec = absl::base_internal::SpinLockSuggestedDelayNS(loop);
nanosleep(&tm, nullptr);
}
}
ABSL_ATTRIBUTE_WEAK void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockWake)(
std::atomic<uint32_t>* /* lock_word */, bool /* all */) {}
} // extern "C"

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_SPINLOCK_WAIT_H_
#define ABSL_BASE_INTERNAL_SPINLOCK_WAIT_H_
// Operations to make atomic transitions on a word, and to allow
// waiting for those transitions to become possible.
#include <stdint.h>
#include <atomic>
#include "absl/base/internal/scheduling_mode.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// SpinLockWait() waits until it can perform one of several transitions from
// "from" to "to". It returns when it performs a transition where done==true.
struct SpinLockWaitTransition {
uint32_t from;
uint32_t to;
bool done;
};
// Wait until *w can transition from trans[i].from to trans[i].to for some i
// satisfying 0<=i<n && trans[i].done, atomically make the transition,
// then return the old value of *w. Make any other atomic transitions
// where !trans[i].done, but continue waiting.
//
// Wakeups for threads blocked on SpinLockWait do not respect priorities.
uint32_t SpinLockWait(std::atomic<uint32_t> *w, int n,
const SpinLockWaitTransition trans[],
SchedulingMode scheduling_mode);
// If possible, wake some thread that has called SpinLockDelay(w, ...). If `all`
// is true, wake all such threads. On some systems, this may be a no-op; on
// those systems, threads calling SpinLockDelay() will always wake eventually
// even if SpinLockWake() is never called.
void SpinLockWake(std::atomic<uint32_t> *w, bool all);
// Wait for an appropriate spin delay on iteration "loop" of a
// spin loop on location *w, whose previously observed value was "value".
// SpinLockDelay() may do nothing, may yield the CPU, may sleep a clock tick,
// or may wait for a call to SpinLockWake(w).
void SpinLockDelay(std::atomic<uint32_t> *w, uint32_t value, int loop,
base_internal::SchedulingMode scheduling_mode);
// Helper used by AbslInternalSpinLockDelay.
// Returns a suggested delay in nanoseconds for iteration number "loop".
int SpinLockSuggestedDelayNS(int loop);
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
// In some build configurations we pass --detect-odr-violations to the
// gold linker. This causes it to flag weak symbol overrides as ODR
// violations. Because ODR only applies to C++ and not C,
// --detect-odr-violations ignores symbols not mangled with C++ names.
// By changing our extension points to be extern "C", we dodge this
// check.
extern "C" {
void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockWake)(std::atomic<uint32_t> *w,
bool all);
void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockDelay)(
std::atomic<uint32_t> *w, uint32_t value, int loop,
absl::base_internal::SchedulingMode scheduling_mode);
}
inline void absl::base_internal::SpinLockWake(std::atomic<uint32_t> *w,
bool all) {
ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockWake)(w, all);
}
inline void absl::base_internal::SpinLockDelay(
std::atomic<uint32_t> *w, uint32_t value, int loop,
absl::base_internal::SchedulingMode scheduling_mode) {
ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockDelay)
(w, value, loop, scheduling_mode);
}
#endif // ABSL_BASE_INTERNAL_SPINLOCK_WAIT_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// This file is a Win32-specific part of spinlock_wait.cc
#include <windows.h>
#include <atomic>
#include "absl/base/internal/scheduling_mode.h"
extern "C" {
void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockDelay)(
std::atomic<uint32_t>* /* lock_word */, uint32_t /* value */, int loop,
absl::base_internal::SchedulingMode /* mode */) {
if (loop == 0) {
} else if (loop == 1) {
Sleep(0);
} else {
// SpinLockSuggestedDelayNS() always returns a positive integer, so this
// static_cast is safe.
Sleep(static_cast<DWORD>(
absl::base_internal::SpinLockSuggestedDelayNS(loop) / 1000000));
}
}
void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockWake)(
std::atomic<uint32_t>* /* lock_word */, bool /* all */) {}
} // extern "C"

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// Copyright 2020 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_STRERROR_H_
#define ABSL_BASE_INTERNAL_STRERROR_H_
#include <string>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// A portable and thread-safe alternative to C89's `strerror`.
//
// The C89 specification of `strerror` is not suitable for use in a
// multi-threaded application as the returned string may be changed by calls to
// `strerror` from another thread. The many non-stdlib alternatives differ
// enough in their names, availability, and semantics to justify this wrapper
// around them. `errno` will not be modified by a call to `absl::StrError`.
std::string StrError(int errnum);
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_STRERROR_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// This file includes routines to find out characteristics
// of the machine a program is running on. It is undoubtedly
// system-dependent.
// Functions listed here that accept a pid_t as an argument act on the
// current process if the pid_t argument is 0
// All functions here are thread-hostile due to file caching unless
// commented otherwise.
#ifndef ABSL_BASE_INTERNAL_SYSINFO_H_
#define ABSL_BASE_INTERNAL_SYSINFO_H_
#ifndef _WIN32
#include <sys/types.h>
#endif
#include <cstdint>
#include "absl/base/config.h"
#include "absl/base/port.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// Nominal core processor cycles per second of each processor. This is _not_
// necessarily the frequency of the CycleClock counter (see cycleclock.h)
// Thread-safe.
double NominalCPUFrequency();
// Number of logical processors (hyperthreads) in system. Thread-safe.
int NumCPUs();
// Return the thread id of the current thread, as told by the system.
// No two currently-live threads implemented by the OS shall have the same ID.
// Thread ids of exited threads may be reused. Multiple user-level threads
// may have the same thread ID if multiplexed on the same OS thread.
//
// On Linux, you may send a signal to the resulting ID with kill(). However,
// it is recommended for portability that you use pthread_kill() instead.
#ifdef _WIN32
// On Windows, process id and thread id are of the same type according to the
// return types of GetProcessId() and GetThreadId() are both DWORD, an unsigned
// 32-bit type.
using pid_t = uint32_t;
#endif
pid_t GetTID();
// Like GetTID(), but caches the result in thread-local storage in order
// to avoid unnecessary system calls. Note that there are some cases where
// one must call through to GetTID directly, which is why this exists as a
// separate function. For example, GetCachedTID() is not safe to call in
// an asynchronous signal-handling context nor right after a call to fork().
pid_t GetCachedTID();
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_SYSINFO_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Each active thread has an ThreadIdentity that may represent the thread in
// various level interfaces. ThreadIdentity objects are never deallocated.
// When a thread terminates, its ThreadIdentity object may be reused for a
// thread created later.
#ifndef ABSL_BASE_INTERNAL_THREAD_IDENTITY_H_
#define ABSL_BASE_INTERNAL_THREAD_IDENTITY_H_
#ifndef _WIN32
#include <pthread.h>
// Defines __GOOGLE_GRTE_VERSION__ (via glibc-specific features.h) when
// supported.
#include <unistd.h>
#endif
#include <atomic>
#include <cstdint>
#include "absl/base/config.h"
#include "absl/base/internal/per_thread_tls.h"
#include "absl/base/optimization.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
struct SynchLocksHeld;
struct SynchWaitParams;
namespace base_internal {
class SpinLock;
struct ThreadIdentity;
// Used by the implementation of absl::Mutex and absl::CondVar.
struct PerThreadSynch {
// The internal representation of absl::Mutex and absl::CondVar rely
// on the alignment of PerThreadSynch. Both store the address of the
// PerThreadSynch in the high-order bits of their internal state,
// which means the low kLowZeroBits of the address of PerThreadSynch
// must be zero.
static constexpr int kLowZeroBits = 8;
static constexpr int kAlignment = 1 << kLowZeroBits;
// Returns the associated ThreadIdentity.
// This can be implemented as a cast because we guarantee
// PerThreadSynch is the first element of ThreadIdentity.
ThreadIdentity* thread_identity() {
return reinterpret_cast<ThreadIdentity*>(this);
}
PerThreadSynch* next; // Circular waiter queue; initialized to 0.
PerThreadSynch* skip; // If non-zero, all entries in Mutex queue
// up to and including "skip" have same
// condition as this, and will be woken later
bool may_skip; // if false while on mutex queue, a mutex unlocker
// is using this PerThreadSynch as a terminator. Its
// skip field must not be filled in because the loop
// might then skip over the terminator.
bool wake; // This thread is to be woken from a Mutex.
// If "x" is on a waiter list for a mutex, "x->cond_waiter" is true iff the
// waiter is waiting on the mutex as part of a CV Wait or Mutex Await.
//
// The value of "x->cond_waiter" is meaningless if "x" is not on a
// Mutex waiter list.
bool cond_waiter;
bool maybe_unlocking; // Valid at head of Mutex waiter queue;
// true if UnlockSlow could be searching
// for a waiter to wake. Used for an optimization
// in Enqueue(). true is always a valid value.
// Can be reset to false when the unlocker or any
// writer releases the lock, or a reader fully
// releases the lock. It may not be set to false
// by a reader that decrements the count to
// non-zero. protected by mutex spinlock
bool suppress_fatal_errors; // If true, try to proceed even in the face
// of broken invariants. This is used within
// fatal signal handlers to improve the
// chances of debug logging information being
// output successfully.
int priority; // Priority of thread (updated every so often).
// State values:
// kAvailable: This PerThreadSynch is available.
// kQueued: This PerThreadSynch is unavailable, it's currently queued on a
// Mutex or CondVar waistlist.
//
// Transitions from kQueued to kAvailable require a release
// barrier. This is needed as a waiter may use "state" to
// independently observe that it's no longer queued.
//
// Transitions from kAvailable to kQueued require no barrier, they
// are externally ordered by the Mutex.
enum State { kAvailable, kQueued };
std::atomic<State> state;
// The wait parameters of the current wait. waitp is null if the
// thread is not waiting. Transitions from null to non-null must
// occur before the enqueue commit point (state = kQueued in
// Enqueue() and CondVarEnqueue()). Transitions from non-null to
// null must occur after the wait is finished (state = kAvailable in
// Mutex::Block() and CondVar::WaitCommon()). This field may be
// changed only by the thread that describes this PerThreadSynch. A
// special case is Fer(), which calls Enqueue() on another thread,
// but with an identical SynchWaitParams pointer, thus leaving the
// pointer unchanged.
SynchWaitParams* waitp;
intptr_t readers; // Number of readers in mutex.
// When priority will next be read (cycles).
int64_t next_priority_read_cycles;
// Locks held; used during deadlock detection.
// Allocated in Synch_GetAllLocks() and freed in ReclaimThreadIdentity().
SynchLocksHeld* all_locks;
};
// The instances of this class are allocated in NewThreadIdentity() with an
// alignment of PerThreadSynch::kAlignment.
//
// NOTE: The layout of fields in this structure is critical, please do not
// add, remove, or modify the field placements without fully auditing the
// layout.
struct ThreadIdentity {
// Must be the first member. The Mutex implementation requires that
// the PerThreadSynch object associated with each thread is
// PerThreadSynch::kAlignment aligned. We provide this alignment on
// ThreadIdentity itself.
PerThreadSynch per_thread_synch;
// Private: Reserved for absl::synchronization_internal::Waiter.
struct WaiterState {
alignas(void*) char data[256];
} waiter_state;
// Used by PerThreadSem::{Get,Set}ThreadBlockedCounter().
std::atomic<int>* blocked_count_ptr;
// The following variables are mostly read/written just by the
// thread itself. The only exception is that these are read by
// a ticker thread as a hint.
std::atomic<int> ticker; // Tick counter, incremented once per second.
std::atomic<int> wait_start; // Ticker value when thread started waiting.
std::atomic<bool> is_idle; // Has thread become idle yet?
ThreadIdentity* next;
};
// Returns the ThreadIdentity object representing the calling thread; guaranteed
// to be unique for its lifetime. The returned object will remain valid for the
// program's lifetime; although it may be re-assigned to a subsequent thread.
// If one does not exist, return nullptr instead.
//
// Does not malloc(*), and is async-signal safe.
// [*] Technically pthread_setspecific() does malloc on first use; however this
// is handled internally within tcmalloc's initialization already. Note that
// darwin does *not* use tcmalloc, so this can catch you if using MallocHooks
// on Apple platforms. Whatever function is calling your MallocHooks will need
// to watch for recursion on Apple platforms.
//
// New ThreadIdentity objects can be constructed and associated with a thread
// by calling GetOrCreateCurrentThreadIdentity() in per-thread-sem.h.
ThreadIdentity* CurrentThreadIdentityIfPresent();
using ThreadIdentityReclaimerFunction = void (*)(void*);
// Sets the current thread identity to the given value. 'reclaimer' is a
// pointer to the global function for cleaning up instances on thread
// destruction.
void SetCurrentThreadIdentity(ThreadIdentity* identity,
ThreadIdentityReclaimerFunction reclaimer);
// Removes the currently associated ThreadIdentity from the running thread.
// This must be called from inside the ThreadIdentityReclaimerFunction, and only
// from that function.
void ClearCurrentThreadIdentity();
// May be chosen at compile time via: -DABSL_FORCE_THREAD_IDENTITY_MODE=<mode
// index>
#ifdef ABSL_THREAD_IDENTITY_MODE_USE_POSIX_SETSPECIFIC
#error ABSL_THREAD_IDENTITY_MODE_USE_POSIX_SETSPECIFIC cannot be directly set
#else
#define ABSL_THREAD_IDENTITY_MODE_USE_POSIX_SETSPECIFIC 0
#endif
#ifdef ABSL_THREAD_IDENTITY_MODE_USE_TLS
#error ABSL_THREAD_IDENTITY_MODE_USE_TLS cannot be directly set
#else
#define ABSL_THREAD_IDENTITY_MODE_USE_TLS 1
#endif
#ifdef ABSL_THREAD_IDENTITY_MODE_USE_CPP11
#error ABSL_THREAD_IDENTITY_MODE_USE_CPP11 cannot be directly set
#else
#define ABSL_THREAD_IDENTITY_MODE_USE_CPP11 2
#endif
#ifdef ABSL_THREAD_IDENTITY_MODE
#error ABSL_THREAD_IDENTITY_MODE cannot be directly set
#elif defined(ABSL_FORCE_THREAD_IDENTITY_MODE)
#define ABSL_THREAD_IDENTITY_MODE ABSL_FORCE_THREAD_IDENTITY_MODE
#elif defined(_WIN32) && !defined(__MINGW32__)
#define ABSL_THREAD_IDENTITY_MODE ABSL_THREAD_IDENTITY_MODE_USE_CPP11
#elif defined(__APPLE__) && defined(ABSL_HAVE_THREAD_LOCAL)
#define ABSL_THREAD_IDENTITY_MODE ABSL_THREAD_IDENTITY_MODE_USE_CPP11
#elif ABSL_PER_THREAD_TLS && defined(__GOOGLE_GRTE_VERSION__) && \
(__GOOGLE_GRTE_VERSION__ >= 20140228L)
// Support for async-safe TLS was specifically added in GRTEv4. It's not
// present in the upstream eglibc.
// Note: Current default for production systems.
#define ABSL_THREAD_IDENTITY_MODE ABSL_THREAD_IDENTITY_MODE_USE_TLS
#else
#define ABSL_THREAD_IDENTITY_MODE \
ABSL_THREAD_IDENTITY_MODE_USE_POSIX_SETSPECIFIC
#endif
#if ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS || \
ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_CPP11
#if ABSL_PER_THREAD_TLS
ABSL_CONST_INIT extern ABSL_PER_THREAD_TLS_KEYWORD ThreadIdentity*
thread_identity_ptr;
#elif defined(ABSL_HAVE_THREAD_LOCAL)
ABSL_CONST_INIT extern thread_local ThreadIdentity* thread_identity_ptr;
#else
#error Thread-local storage not detected on this platform
#endif
// thread_local variables cannot be in headers exposed by DLLs or in certain
// build configurations on Apple platforms. However, it is important for
// performance reasons in general that `CurrentThreadIdentityIfPresent` be
// inlined. In the other cases we opt to have the function not be inlined. Note
// that `CurrentThreadIdentityIfPresent` is declared above so we can exclude
// this entire inline definition.
#if !defined(__APPLE__) && !defined(ABSL_BUILD_DLL) && \
!defined(ABSL_CONSUME_DLL)
#define ABSL_INTERNAL_INLINE_CURRENT_THREAD_IDENTITY_IF_PRESENT 1
#endif
#ifdef ABSL_INTERNAL_INLINE_CURRENT_THREAD_IDENTITY_IF_PRESENT
inline ThreadIdentity* CurrentThreadIdentityIfPresent() {
return thread_identity_ptr;
}
#endif
#elif ABSL_THREAD_IDENTITY_MODE != \
ABSL_THREAD_IDENTITY_MODE_USE_POSIX_SETSPECIFIC
#error Unknown ABSL_THREAD_IDENTITY_MODE
#endif
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_THREAD_IDENTITY_H_

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//
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef ABSL_BASE_INTERNAL_THROW_DELEGATE_H_
#define ABSL_BASE_INTERNAL_THROW_DELEGATE_H_
#include <string>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// Helper functions that allow throwing exceptions consistently from anywhere.
// The main use case is for header-based libraries (eg templates), as they will
// be built by many different targets with their own compiler options.
// In particular, this will allow a safe way to throw exceptions even if the
// caller is compiled with -fno-exceptions. This is intended for implementing
// things like map<>::at(), which the standard documents as throwing an
// exception on error.
//
// Using other techniques like #if tricks could lead to ODR violations.
//
// You shouldn't use it unless you're writing code that you know will be built
// both with and without exceptions and you need to conform to an interface
// that uses exceptions.
[[noreturn]] void ThrowStdLogicError(const std::string& what_arg);
[[noreturn]] void ThrowStdLogicError(const char* what_arg);
[[noreturn]] void ThrowStdInvalidArgument(const std::string& what_arg);
[[noreturn]] void ThrowStdInvalidArgument(const char* what_arg);
[[noreturn]] void ThrowStdDomainError(const std::string& what_arg);
[[noreturn]] void ThrowStdDomainError(const char* what_arg);
[[noreturn]] void ThrowStdLengthError(const std::string& what_arg);
[[noreturn]] void ThrowStdLengthError(const char* what_arg);
[[noreturn]] void ThrowStdOutOfRange(const std::string& what_arg);
[[noreturn]] void ThrowStdOutOfRange(const char* what_arg);
[[noreturn]] void ThrowStdRuntimeError(const std::string& what_arg);
[[noreturn]] void ThrowStdRuntimeError(const char* what_arg);
[[noreturn]] void ThrowStdRangeError(const std::string& what_arg);
[[noreturn]] void ThrowStdRangeError(const char* what_arg);
[[noreturn]] void ThrowStdOverflowError(const std::string& what_arg);
[[noreturn]] void ThrowStdOverflowError(const char* what_arg);
[[noreturn]] void ThrowStdUnderflowError(const std::string& what_arg);
[[noreturn]] void ThrowStdUnderflowError(const char* what_arg);
[[noreturn]] void ThrowStdBadFunctionCall();
[[noreturn]] void ThrowStdBadAlloc();
// ThrowStdBadArrayNewLength() cannot be consistently supported because
// std::bad_array_new_length is missing in libstdc++ until 4.9.0.
// https://gcc.gnu.org/onlinedocs/gcc-4.8.3/libstdc++/api/a01379_source.html
// https://gcc.gnu.org/onlinedocs/gcc-4.9.0/libstdc++/api/a01327_source.html
// libcxx (as of 3.2) and msvc (as of 2015) both have it.
// [[noreturn]] void ThrowStdBadArrayNewLength();
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_THROW_DELEGATE_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// This file is intended solely for spinlock.h.
// It provides ThreadSanitizer annotations for custom mutexes.
// See <sanitizer/tsan_interface.h> for meaning of these annotations.
#ifndef ABSL_BASE_INTERNAL_TSAN_MUTEX_INTERFACE_H_
#define ABSL_BASE_INTERNAL_TSAN_MUTEX_INTERFACE_H_
#include "absl/base/config.h"
// ABSL_INTERNAL_HAVE_TSAN_INTERFACE
// Macro intended only for internal use.
//
// Checks whether LLVM Thread Sanitizer interfaces are available.
// First made available in LLVM 5.0 (Sep 2017).
#ifdef ABSL_INTERNAL_HAVE_TSAN_INTERFACE
#error "ABSL_INTERNAL_HAVE_TSAN_INTERFACE cannot be directly set."
#endif
#if defined(ABSL_HAVE_THREAD_SANITIZER) && defined(__has_include)
#if __has_include(<sanitizer/tsan_interface.h>)
#define ABSL_INTERNAL_HAVE_TSAN_INTERFACE 1
#endif
#endif
#ifdef ABSL_INTERNAL_HAVE_TSAN_INTERFACE
#include <sanitizer/tsan_interface.h>
#define ABSL_TSAN_MUTEX_CREATE __tsan_mutex_create
#define ABSL_TSAN_MUTEX_DESTROY __tsan_mutex_destroy
#define ABSL_TSAN_MUTEX_PRE_LOCK __tsan_mutex_pre_lock
#define ABSL_TSAN_MUTEX_POST_LOCK __tsan_mutex_post_lock
#define ABSL_TSAN_MUTEX_PRE_UNLOCK __tsan_mutex_pre_unlock
#define ABSL_TSAN_MUTEX_POST_UNLOCK __tsan_mutex_post_unlock
#define ABSL_TSAN_MUTEX_PRE_SIGNAL __tsan_mutex_pre_signal
#define ABSL_TSAN_MUTEX_POST_SIGNAL __tsan_mutex_post_signal
#define ABSL_TSAN_MUTEX_PRE_DIVERT __tsan_mutex_pre_divert
#define ABSL_TSAN_MUTEX_POST_DIVERT __tsan_mutex_post_divert
#else
#define ABSL_TSAN_MUTEX_CREATE(...)
#define ABSL_TSAN_MUTEX_DESTROY(...)
#define ABSL_TSAN_MUTEX_PRE_LOCK(...)
#define ABSL_TSAN_MUTEX_POST_LOCK(...)
#define ABSL_TSAN_MUTEX_PRE_UNLOCK(...)
#define ABSL_TSAN_MUTEX_POST_UNLOCK(...)
#define ABSL_TSAN_MUTEX_PRE_SIGNAL(...)
#define ABSL_TSAN_MUTEX_POST_SIGNAL(...)
#define ABSL_TSAN_MUTEX_PRE_DIVERT(...)
#define ABSL_TSAN_MUTEX_POST_DIVERT(...)
#endif
#endif // ABSL_BASE_INTERNAL_TSAN_MUTEX_INTERFACE_H_

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//
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef ABSL_BASE_INTERNAL_UNALIGNED_ACCESS_H_
#define ABSL_BASE_INTERNAL_UNALIGNED_ACCESS_H_
#include <string.h>
#include <cstdint>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
// unaligned APIs
// Portable handling of unaligned loads, stores, and copies.
// The unaligned API is C++ only. The declarations use C++ features
// (namespaces, inline) which are absent or incompatible in C.
#if defined(__cplusplus)
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
inline uint16_t UnalignedLoad16(const void *p) {
uint16_t t;
memcpy(&t, p, sizeof t);
return t;
}
inline uint32_t UnalignedLoad32(const void *p) {
uint32_t t;
memcpy(&t, p, sizeof t);
return t;
}
inline uint64_t UnalignedLoad64(const void *p) {
uint64_t t;
memcpy(&t, p, sizeof t);
return t;
}
inline void UnalignedStore16(void *p, uint16_t v) { memcpy(p, &v, sizeof v); }
inline void UnalignedStore32(void *p, uint32_t v) { memcpy(p, &v, sizeof v); }
inline void UnalignedStore64(void *p, uint64_t v) { memcpy(p, &v, sizeof v); }
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#define ABSL_INTERNAL_UNALIGNED_LOAD16(_p) \
(absl::base_internal::UnalignedLoad16(_p))
#define ABSL_INTERNAL_UNALIGNED_LOAD32(_p) \
(absl::base_internal::UnalignedLoad32(_p))
#define ABSL_INTERNAL_UNALIGNED_LOAD64(_p) \
(absl::base_internal::UnalignedLoad64(_p))
#define ABSL_INTERNAL_UNALIGNED_STORE16(_p, _val) \
(absl::base_internal::UnalignedStore16(_p, _val))
#define ABSL_INTERNAL_UNALIGNED_STORE32(_p, _val) \
(absl::base_internal::UnalignedStore32(_p, _val))
#define ABSL_INTERNAL_UNALIGNED_STORE64(_p, _val) \
(absl::base_internal::UnalignedStore64(_p, _val))
#endif // defined(__cplusplus), end of unaligned API
#endif // ABSL_BASE_INTERNAL_UNALIGNED_ACCESS_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// UnscaledCycleClock
// An UnscaledCycleClock yields the value and frequency of a cycle counter
// that increments at a rate that is approximately constant.
// This class is for internal use only, you should consider using CycleClock
// instead.
//
// Notes:
// The cycle counter frequency is not necessarily the core clock frequency.
// That is, CycleCounter cycles are not necessarily "CPU cycles".
//
// An arbitrary offset may have been added to the counter at power on.
//
// On some platforms, the rate and offset of the counter may differ
// slightly when read from different CPUs of a multiprocessor. Usually,
// we try to ensure that the operating system adjusts values periodically
// so that values agree approximately. If you need stronger guarantees,
// consider using alternate interfaces.
//
// The CPU is not required to maintain the ordering of a cycle counter read
// with respect to surrounding instructions.
#ifndef ABSL_BASE_INTERNAL_UNSCALEDCYCLECLOCK_H_
#define ABSL_BASE_INTERNAL_UNSCALEDCYCLECLOCK_H_
#include <cstdint>
#if defined(__APPLE__)
#include <TargetConditionals.h>
#endif
#include "absl/base/config.h"
#include "absl/base/internal/unscaledcycleclock_config.h"
#if ABSL_USE_UNSCALED_CYCLECLOCK
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace time_internal {
class UnscaledCycleClockWrapperForGetCurrentTime;
} // namespace time_internal
namespace base_internal {
class CycleClock;
class UnscaledCycleClockWrapperForInitializeFrequency;
class UnscaledCycleClock {
private:
UnscaledCycleClock() = delete;
// Return the value of a cycle counter that counts at a rate that is
// approximately constant.
static int64_t Now();
// Return the how much UnscaledCycleClock::Now() increases per second.
// This is not necessarily the core CPU clock frequency.
// It may be the nominal value report by the kernel, rather than a measured
// value.
static double Frequency();
// Allowed users
friend class base_internal::CycleClock;
friend class time_internal::UnscaledCycleClockWrapperForGetCurrentTime;
friend class base_internal::UnscaledCycleClockWrapperForInitializeFrequency;
};
#if defined(__x86_64__)
inline int64_t UnscaledCycleClock::Now() {
uint64_t low, high;
__asm__ volatile("rdtsc" : "=a"(low), "=d"(high));
return static_cast<int64_t>((high << 32) | low);
}
#endif
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_USE_UNSCALED_CYCLECLOCK
#endif // ABSL_BASE_INTERNAL_UNSCALEDCYCLECLOCK_H_

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// Copyright 2022 The Abseil Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_INTERNAL_UNSCALEDCYCLECLOCK_CONFIG_H_
#define ABSL_BASE_INTERNAL_UNSCALEDCYCLECLOCK_CONFIG_H_
#if defined(__APPLE__)
#include <TargetConditionals.h>
#endif
// The following platforms have an implementation of a hardware counter.
#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__) || \
defined(__powerpc__) || defined(__ppc__) || defined(__riscv) || \
defined(_M_IX86) || (defined(_M_X64) && !defined(_M_ARM64EC))
#define ABSL_HAVE_UNSCALED_CYCLECLOCK_IMPLEMENTATION 1
#else
#define ABSL_HAVE_UNSCALED_CYCLECLOCK_IMPLEMENTATION 0
#endif
// The following platforms often disable access to the hardware
// counter (through a sandbox) even if the underlying hardware has a
// usable counter. The CycleTimer interface also requires a *scaled*
// CycleClock that runs at atleast 1 MHz. We've found some Android
// ARM64 devices where this is not the case, so we disable it by
// default on Android ARM64.
#if defined(__native_client__) || (defined(__APPLE__)) || \
(defined(__ANDROID__) && defined(__aarch64__))
#define ABSL_USE_UNSCALED_CYCLECLOCK_DEFAULT 0
#else
#define ABSL_USE_UNSCALED_CYCLECLOCK_DEFAULT 1
#endif
// UnscaledCycleClock is an optional internal feature.
// Use "#if ABSL_USE_UNSCALED_CYCLECLOCK" to test for its presence.
// Can be overridden at compile-time via -DABSL_USE_UNSCALED_CYCLECLOCK=0|1
#if !defined(ABSL_USE_UNSCALED_CYCLECLOCK)
#define ABSL_USE_UNSCALED_CYCLECLOCK \
(ABSL_HAVE_UNSCALED_CYCLECLOCK_IMPLEMENTATION && \
ABSL_USE_UNSCALED_CYCLECLOCK_DEFAULT)
#endif
#if ABSL_USE_UNSCALED_CYCLECLOCK
// This macro can be used to test if UnscaledCycleClock::Frequency()
// is NominalCPUFrequency() on a particular platform.
#if (defined(__i386__) || defined(__x86_64__) || defined(__riscv) || \
defined(_M_IX86) || defined(_M_X64))
#define ABSL_INTERNAL_UNSCALED_CYCLECLOCK_FREQUENCY_IS_CPU_FREQUENCY
#endif
#endif
#endif // ABSL_BASE_INTERNAL_UNSCALEDCYCLECLOCK_CONFIG_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_LOG_SEVERITY_H_
#define ABSL_BASE_LOG_SEVERITY_H_
#include <array>
#include <ostream>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
// absl::LogSeverity
//
// Four severity levels are defined. Logging APIs should terminate the program
// when a message is logged at severity `kFatal`; the other levels have no
// special semantics.
//
// Values other than the four defined levels (e.g. produced by `static_cast`)
// are valid, but their semantics when passed to a function, macro, or flag
// depend on the function, macro, or flag. The usual behavior is to normalize
// such values to a defined severity level, however in some cases values other
// than the defined levels are useful for comparison.
//
// Example:
//
// // Effectively disables all logging:
// SetMinLogLevel(static_cast<absl::LogSeverity>(100));
//
// Abseil flags may be defined with type `LogSeverity`. Dependency layering
// constraints require that the `AbslParseFlag()` overload be declared and
// defined in the flags library itself rather than here. The `AbslUnparseFlag()`
// overload is defined there as well for consistency.
//
// absl::LogSeverity Flag String Representation
//
// An `absl::LogSeverity` has a string representation used for parsing
// command-line flags based on the enumerator name (e.g. `kFatal`) or
// its unprefixed name (without the `k`) in any case-insensitive form. (E.g.
// "FATAL", "fatal" or "Fatal" are all valid.) Unparsing such flags produces an
// unprefixed string representation in all caps (e.g. "FATAL") or an integer.
//
// Additionally, the parser accepts arbitrary integers (as if the type were
// `int`).
//
// Examples:
//
// --my_log_level=kInfo
// --my_log_level=INFO
// --my_log_level=info
// --my_log_level=0
//
// `DFATAL` and `kLogDebugFatal` are similarly accepted.
//
// Unparsing a flag produces the same result as `absl::LogSeverityName()` for
// the standard levels and a base-ten integer otherwise.
enum class LogSeverity : int {
kInfo = 0,
kWarning = 1,
kError = 2,
kFatal = 3,
};
// LogSeverities()
//
// Returns an iterable of all standard `absl::LogSeverity` values, ordered from
// least to most severe.
constexpr std::array<absl::LogSeverity, 4> LogSeverities() {
return {{absl::LogSeverity::kInfo, absl::LogSeverity::kWarning,
absl::LogSeverity::kError, absl::LogSeverity::kFatal}};
}
// `absl::kLogDebugFatal` equals `absl::LogSeverity::kFatal` in debug builds
// (i.e. when `NDEBUG` is not defined) and `absl::LogSeverity::kError`
// otherwise. Avoid ODR-using this variable as it has internal linkage and thus
// distinct storage in different TUs.
#ifdef NDEBUG
static constexpr absl::LogSeverity kLogDebugFatal = absl::LogSeverity::kError;
#else
static constexpr absl::LogSeverity kLogDebugFatal = absl::LogSeverity::kFatal;
#endif
// LogSeverityName()
//
// Returns the all-caps string representation (e.g. "INFO") of the specified
// severity level if it is one of the standard levels and "UNKNOWN" otherwise.
constexpr const char* LogSeverityName(absl::LogSeverity s) {
switch (s) {
case absl::LogSeverity::kInfo: return "INFO";
case absl::LogSeverity::kWarning: return "WARNING";
case absl::LogSeverity::kError: return "ERROR";
case absl::LogSeverity::kFatal: return "FATAL";
default: return "UNKNOWN";
}
}
// NormalizeLogSeverity()
//
// Values less than `kInfo` normalize to `kInfo`; values greater than `kFatal`
// normalize to `kError` (**NOT** `kFatal`).
constexpr absl::LogSeverity NormalizeLogSeverity(absl::LogSeverity s) {
absl::LogSeverity n = s;
if (n < absl::LogSeverity::kInfo) n = absl::LogSeverity::kInfo;
if (n > absl::LogSeverity::kFatal) n = absl::LogSeverity::kError;
return n;
}
constexpr absl::LogSeverity NormalizeLogSeverity(int s) {
return absl::NormalizeLogSeverity(static_cast<absl::LogSeverity>(s));
}
// operator<<
//
// The exact representation of a streamed `absl::LogSeverity` is deliberately
// unspecified; do not rely on it.
std::ostream& operator<<(std::ostream& os, absl::LogSeverity s);
// Enums representing a lower bound for LogSeverity. APIs that only operate on
// messages of at least a certain level (for example, `SetMinLogLevel()`) use
// this type to specify that level. absl::LogSeverityAtLeast::kInfinity is
// a level above all threshold levels and therefore no log message will
// ever meet this threshold.
enum class LogSeverityAtLeast : int {
kInfo = static_cast<int>(absl::LogSeverity::kInfo),
kWarning = static_cast<int>(absl::LogSeverity::kWarning),
kError = static_cast<int>(absl::LogSeverity::kError),
kFatal = static_cast<int>(absl::LogSeverity::kFatal),
kInfinity = 1000,
};
std::ostream& operator<<(std::ostream& os, absl::LogSeverityAtLeast s);
// Enums representing an upper bound for LogSeverity. APIs that only operate on
// messages of at most a certain level (for example, buffer all messages at or
// below a certain level) use this type to specify that level.
// absl::LogSeverityAtMost::kNegativeInfinity is a level below all threshold
// levels and therefore will exclude all log messages.
enum class LogSeverityAtMost : int {
kNegativeInfinity = -1000,
kInfo = static_cast<int>(absl::LogSeverity::kInfo),
kWarning = static_cast<int>(absl::LogSeverity::kWarning),
kError = static_cast<int>(absl::LogSeverity::kError),
kFatal = static_cast<int>(absl::LogSeverity::kFatal),
};
std::ostream& operator<<(std::ostream& os, absl::LogSeverityAtMost s);
#define COMPOP(op1, op2, T) \
constexpr bool operator op1(absl::T lhs, absl::LogSeverity rhs) { \
return static_cast<absl::LogSeverity>(lhs) op1 rhs; \
} \
constexpr bool operator op2(absl::LogSeverity lhs, absl::T rhs) { \
return lhs op2 static_cast<absl::LogSeverity>(rhs); \
}
// Comparisons between `LogSeverity` and `LogSeverityAtLeast`/
// `LogSeverityAtMost` are only supported in one direction.
// Valid checks are:
// LogSeverity >= LogSeverityAtLeast
// LogSeverity < LogSeverityAtLeast
// LogSeverity <= LogSeverityAtMost
// LogSeverity > LogSeverityAtMost
COMPOP(>, <, LogSeverityAtLeast)
COMPOP(<=, >=, LogSeverityAtLeast)
COMPOP(<, >, LogSeverityAtMost)
COMPOP(>=, <=, LogSeverityAtMost)
#undef COMPOP
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_LOG_SEVERITY_H_

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//
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: macros.h
// -----------------------------------------------------------------------------
//
// This header file defines the set of language macros used within Abseil code.
// For the set of macros used to determine supported compilers and platforms,
// see absl/base/config.h instead.
//
// This code is compiled directly on many platforms, including client
// platforms like Windows, Mac, and embedded systems. Before making
// any changes here, make sure that you're not breaking any platforms.
#ifndef ABSL_BASE_MACROS_H_
#define ABSL_BASE_MACROS_H_
#include <cassert>
#include <cstddef>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#include "absl/base/optimization.h"
#include "absl/base/port.h"
// ABSL_ARRAYSIZE()
//
// Returns the number of elements in an array as a compile-time constant, which
// can be used in defining new arrays. If you use this macro on a pointer by
// mistake, you will get a compile-time error.
#define ABSL_ARRAYSIZE(array) \
(sizeof(::absl::macros_internal::ArraySizeHelper(array)))
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace macros_internal {
// Note: this internal template function declaration is used by ABSL_ARRAYSIZE.
// The function doesn't need a definition, as we only use its type.
template <typename T, size_t N>
auto ArraySizeHelper(const T (&array)[N]) -> char (&)[N];
} // namespace macros_internal
ABSL_NAMESPACE_END
} // namespace absl
// ABSL_BAD_CALL_IF()
//
// Used on a function overload to trap bad calls: any call that matches the
// overload will cause a compile-time error. This macro uses a clang-specific
// "enable_if" attribute, as described at
// https://clang.llvm.org/docs/AttributeReference.html#enable-if
//
// Overloads which use this macro should be bracketed by
// `#ifdef ABSL_BAD_CALL_IF`.
//
// Example:
//
// int isdigit(int c);
// #ifdef ABSL_BAD_CALL_IF
// int isdigit(int c)
// ABSL_BAD_CALL_IF(c <= -1 || c > 255,
// "'c' must have the value of an unsigned char or EOF");
// #endif // ABSL_BAD_CALL_IF
#if ABSL_HAVE_ATTRIBUTE(enable_if)
#define ABSL_BAD_CALL_IF(expr, msg) \
__attribute__((enable_if(expr, "Bad call trap"), unavailable(msg)))
#endif
// ABSL_ASSERT()
//
// In C++11, `assert` can't be used portably within constexpr functions.
// ABSL_ASSERT functions as a runtime assert but works in C++11 constexpr
// functions. Example:
//
// constexpr double Divide(double a, double b) {
// return ABSL_ASSERT(b != 0), a / b;
// }
//
// This macro is inspired by
// https://akrzemi1.wordpress.com/2017/05/18/asserts-in-constexpr-functions/
#if defined(NDEBUG)
#define ABSL_ASSERT(expr) \
(false ? static_cast<void>(expr) : static_cast<void>(0))
#else
#define ABSL_ASSERT(expr) \
(ABSL_PREDICT_TRUE((expr)) ? static_cast<void>(0) \
: [] { assert(false && #expr); }()) // NOLINT
#endif
// `ABSL_INTERNAL_HARDENING_ABORT()` controls how `ABSL_HARDENING_ASSERT()`
// aborts the program in release mode (when NDEBUG is defined). The
// implementation should abort the program as quickly as possible and ideally it
// should not be possible to ignore the abort request.
#define ABSL_INTERNAL_HARDENING_ABORT() \
do { \
ABSL_INTERNAL_IMMEDIATE_ABORT_IMPL(); \
ABSL_INTERNAL_UNREACHABLE_IMPL(); \
} while (false)
// ABSL_HARDENING_ASSERT()
//
// `ABSL_HARDENING_ASSERT()` is like `ABSL_ASSERT()`, but used to implement
// runtime assertions that should be enabled in hardened builds even when
// `NDEBUG` is defined.
//
// When `NDEBUG` is not defined, `ABSL_HARDENING_ASSERT()` is identical to
// `ABSL_ASSERT()`.
//
// See `ABSL_OPTION_HARDENED` in `absl/base/options.h` for more information on
// hardened mode.
#if ABSL_OPTION_HARDENED == 1 && defined(NDEBUG)
#define ABSL_HARDENING_ASSERT(expr) \
(ABSL_PREDICT_TRUE((expr)) ? static_cast<void>(0) \
: [] { ABSL_INTERNAL_HARDENING_ABORT(); }())
#else
#define ABSL_HARDENING_ASSERT(expr) ABSL_ASSERT(expr)
#endif
#ifdef ABSL_HAVE_EXCEPTIONS
#define ABSL_INTERNAL_TRY try
#define ABSL_INTERNAL_CATCH_ANY catch (...)
#define ABSL_INTERNAL_RETHROW do { throw; } while (false)
#else // ABSL_HAVE_EXCEPTIONS
#define ABSL_INTERNAL_TRY if (true)
#define ABSL_INTERNAL_CATCH_ANY else if (false)
#define ABSL_INTERNAL_RETHROW do {} while (false)
#endif // ABSL_HAVE_EXCEPTIONS
#endif // ABSL_BASE_MACROS_H_

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// Copyright 2023 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: no_destructor.h
// -----------------------------------------------------------------------------
//
// This header file defines the absl::NoDestructor<T> wrapper for defining a
// static type that does not need to be destructed upon program exit. Instead,
// such an object survives during program exit (and can be safely accessed at
// any time).
//
// Objects of such type, if constructed safely and under the right conditions,
// provide two main benefits over other alternatives:
//
// * Global objects not normally allowed due to concerns of destruction order
// (i.e. no "complex globals") can be safely allowed, provided that such
// objects can be constant initialized.
// * Function scope static objects can be optimized to avoid heap allocation,
// pointer chasing, and allow lazy construction.
//
// See below for complete details.
#ifndef ABSL_BASE_NO_DESTRUCTOR_H_
#define ABSL_BASE_NO_DESTRUCTOR_H_
#include <new>
#include <type_traits>
#include <utility>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
// absl::NoDestructor<T>
//
// NoDestructor<T> is a wrapper around an object of type T that behaves as an
// object of type T but never calls T's destructor. NoDestructor<T> makes it
// safer and/or more efficient to use such objects in static storage contexts:
// as global or function scope static variables.
//
// An instance of absl::NoDestructor<T> has similar type semantics to an
// instance of T:
//
// * Constructs in the same manner as an object of type T through perfect
// forwarding.
// * Provides pointer/reference semantic access to the object of type T via
// `->`, `*`, and `get()`.
// (Note that `const NoDestructor<T>` works like a pointer to const `T`.)
//
// An object of type NoDestructor<T> should be defined in static storage:
// as either a global static object, or as a function scope static variable.
//
// Additionally, NoDestructor<T> provides the following benefits:
//
// * Never calls T's destructor for the object
// * If the object is a function-local static variable, the type can be
// lazily constructed.
//
// An object of type NoDestructor<T> is "trivially destructible" in the notion
// that its destructor is never run. Provided that an object of this type can be
// safely initialized and does not need to be cleaned up on program shutdown,
// NoDestructor<T> allows you to define global static variables, since Google's
// C++ style guide ban on such objects doesn't apply to objects that are
// trivially destructible.
//
// Usage as Global Static Variables
//
// NoDestructor<T> allows declaration of a global object with a non-trivial
// constructor in static storage without needing to add a destructor.
// However, such objects still need to worry about initialization order, so
// such objects should be const initialized:
//
// // Global or namespace scope.
// ABSL_CONST_INIT absl::NoDestructor<MyRegistry> reg{"foo", "bar", 8008};
//
// Note that if your object already has a trivial destructor, you don't need to
// use NoDestructor<T>.
//
// Usage as Function Scope Static Variables
//
// Function static objects will be lazily initialized within static storage:
//
// // Function scope.
// const std::string& MyString() {
// static const absl::NoDestructor<std::string> x("foo");
// return *x;
// }
//
// For function static variables, NoDestructor avoids heap allocation and can be
// inlined in static storage, resulting in exactly-once, thread-safe
// construction of an object, and very fast access thereafter (the cost is a few
// extra cycles).
//
// Using NoDestructor<T> in this manner is generally better than other patterns
// which require pointer chasing:
//
// // Prefer using absl::NoDestructor<T> instead for the static variable.
// const std::string& MyString() {
// static const std::string* x = new std::string("foo");
// return *x;
// }
//
template <typename T>
class NoDestructor {
public:
// Forwards arguments to the T's constructor: calls T(args...).
template <typename... Ts,
// Disable this overload when it might collide with copy/move.
typename std::enable_if<!std::is_same<void(std::decay_t<Ts>&...),
void(NoDestructor&)>::value,
int>::type = 0>
explicit constexpr NoDestructor(Ts&&... args)
: impl_(std::forward<Ts>(args)...) {}
// Forwards copy and move construction for T. Enables usage like this:
// static NoDestructor<std::array<string, 3>> x{{{"1", "2", "3"}}};
// static NoDestructor<std::vector<int>> x{{1, 2, 3}};
explicit constexpr NoDestructor(const T& x) : impl_(x) {}
explicit constexpr NoDestructor(T&& x)
: impl_(std::move(x)) {}
// No copying.
NoDestructor(const NoDestructor&) = delete;
NoDestructor& operator=(const NoDestructor&) = delete;
// Pretend to be a smart pointer to T with deep constness.
// Never returns a null pointer.
T& operator*() { return *get(); }
T* operator->() { return get(); }
T* get() { return impl_.get(); }
const T& operator*() const { return *get(); }
const T* operator->() const { return get(); }
const T* get() const { return impl_.get(); }
private:
class DirectImpl {
public:
template <typename... Args>
explicit constexpr DirectImpl(Args&&... args)
: value_(std::forward<Args>(args)...) {}
const T* get() const { return &value_; }
T* get() { return &value_; }
private:
T value_;
};
class PlacementImpl {
public:
template <typename... Args>
explicit PlacementImpl(Args&&... args) {
new (&space_) T(std::forward<Args>(args)...);
}
const T* get() const {
return Launder(reinterpret_cast<const T*>(&space_));
}
T* get() { return Launder(reinterpret_cast<T*>(&space_)); }
private:
template <typename P>
static P* Launder(P* p) {
#if defined(__cpp_lib_launder) && __cpp_lib_launder >= 201606L
return std::launder(p);
#elif ABSL_HAVE_BUILTIN(__builtin_launder)
return __builtin_launder(p);
#else
// When `std::launder` or equivalent are not available, we rely on
// undefined behavior, which works as intended on Abseil's officially
// supported platforms as of Q3 2023.
#if defined(__GNUC__) && !defined(__clang__)
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
#endif
return p;
#if defined(__GNUC__) && !defined(__clang__)
#pragma GCC diagnostic pop
#endif
#endif
}
alignas(T) unsigned char space_[sizeof(T)];
};
// If the object is trivially destructible we use a member directly to avoid
// potential once-init runtime initialization. It somewhat defeats the
// purpose of NoDestructor in this case, but this makes the class more
// friendly to generic code.
std::conditional_t<std::is_trivially_destructible<T>::value, DirectImpl,
PlacementImpl>
impl_;
};
#ifdef ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION
// Provide 'Class Template Argument Deduction': the type of NoDestructor's T
// will be the same type as the argument passed to NoDestructor's constructor.
template <typename T>
NoDestructor(T) -> NoDestructor<T>;
#endif // ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_NO_DESTRUCTOR_H_

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// Copyright 2023 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: nullability.h
// -----------------------------------------------------------------------------
//
// This header file defines a set of "templated annotations" for designating the
// expected nullability of pointers. These annotations allow you to designate
// pointers in one of three classification states:
//
// * "Non-null" (for pointers annotated `Nonnull<T>`), indicating that it is
// invalid for the given pointer to ever be null.
// * "Nullable" (for pointers annotated `Nullable<T>`), indicating that it is
// valid for the given pointer to be null.
// * "Unknown" (for pointers annotated `NullabilityUnknown<T>`), indicating
// that the given pointer has not been yet classified as either nullable or
// non-null. This is the default state of unannotated pointers.
//
// NOTE: unannotated pointers implicitly bear the annotation
// `NullabilityUnknown<T>`; you should rarely, if ever, see this annotation used
// in the codebase explicitly.
//
// -----------------------------------------------------------------------------
// Nullability and Contracts
// -----------------------------------------------------------------------------
//
// These nullability annotations allow you to more clearly specify contracts on
// software components by narrowing the *preconditions*, *postconditions*, and
// *invariants* of pointer state(s) in any given interface. It then depends on
// context who is responsible for fulfilling the annotation's requirements.
//
// For example, a function may receive a pointer argument. Designating that
// pointer argument as "non-null" tightens the precondition of the contract of
// that function. It is then the responsibility of anyone calling such a
// function to ensure that the passed pointer is not null.
//
// Similarly, a function may have a pointer as a return value. Designating that
// return value as "non-null" tightens the postcondition of the contract of that
// function. In this case, however, it is the responsibility of the function
// itself to ensure that the returned pointer is not null.
//
// Clearly defining these contracts allows providers (and consumers) of such
// pointers to have more confidence in their null state. If a function declares
// a return value as "non-null", for example, the caller should not need to
// check whether the returned value is `nullptr`; it can simply assume the
// pointer is valid.
//
// Of course most interfaces already have expectations on the nullability state
// of pointers, and these expectations are, in effect, a contract; often,
// however, those contracts are either poorly or partially specified, assumed,
// or misunderstood. These nullability annotations are designed to allow you to
// formalize those contracts within the codebase.
//
// -----------------------------------------------------------------------------
// Using Nullability Annotations
// -----------------------------------------------------------------------------
//
// It is important to note that these annotations are not distinct strong
// *types*. They are alias templates defined to be equal to the underlying
// pointer type. A pointer annotated `Nonnull<T*>`, for example, is simply a
// pointer of type `T*`. Each annotation acts as a form of documentation about
// the contract for the given pointer. Each annotation requires providers or
// consumers of these pointers across API boundaries to take appropriate steps
// when setting or using these pointers:
//
// * "Non-null" pointers should never be null. It is the responsibility of the
// provider of this pointer to ensure that the pointer may never be set to
// null. Consumers of such pointers can treat such pointers as non-null.
// * "Nullable" pointers may or may not be null. Consumers of such pointers
// should precede any usage of that pointer (e.g. a dereference operation)
// with a a `nullptr` check.
// * "Unknown" pointers may be either "non-null" or "nullable" but have not been
// definitively determined to be in either classification state. Providers of
// such pointers across API boundaries should determine -- over time -- to
// annotate the pointer in either of the above two states. Consumers of such
// pointers across an API boundary should continue to treat such pointers as
// they currently do.
//
// Example:
//
// // PaySalary() requires the passed pointer to an `Employee` to be non-null.
// void PaySalary(absl::Nonnull<Employee *> e) {
// pay(e->salary); // OK to dereference
// }
//
// // CompleteTransaction() guarantees the returned pointer to an `Account` to
// // be non-null.
// absl::Nonnull<Account *> balance CompleteTransaction(double fee) {
// ...
// }
//
// // Note that specifying a nullability annotation does not prevent someone
// // from violating the contract:
//
// Nullable<Employee *> find(Map& employees, std::string_view name);
//
// void g(Map& employees) {
// Employee *e = find(employees, "Pat");
// // `e` can now be null.
// PaySalary(e); // Violates contract, but compiles!
// }
//
// Nullability annotations, in other words, are useful for defining and
// narrowing contracts; *enforcement* of those contracts depends on use and any
// additional (static or dynamic analysis) tooling.
//
// NOTE: The "unknown" annotation state indicates that a pointer's contract has
// not yet been positively identified. The unknown state therefore acts as a
// form of documentation of your technical debt, and a codebase that adopts
// nullability annotations should aspire to annotate every pointer as either
// "non-null" or "nullable".
//
// -----------------------------------------------------------------------------
// Applicability of Nullability Annotations
// -----------------------------------------------------------------------------
//
// By default, nullability annotations are applicable to raw and smart
// pointers. User-defined types can indicate compatibility with nullability
// annotations by providing an `absl_nullability_compatible` nested type. The
// actual definition of this inner type is not relevant as it is used merely as
// a marker. It is common to use a using declaration of
// `absl_nullability_compatible` set to void.
//
// // Example:
// struct MyPtr {
// using absl_nullability_compatible = void;
// ...
// };
//
// DISCLAIMER:
// ===========================================================================
// These nullability annotations are primarily a human readable signal about the
// intended contract of the pointer. They are not *types* and do not currently
// provide any correctness guarantees. For example, a pointer annotated as
// `Nonnull<T*>` is *not guaranteed* to be non-null, and the compiler won't
// alert or prevent assignment of a `Nullable<T*>` to a `Nonnull<T*>`.
// ===========================================================================
#ifndef ABSL_BASE_NULLABILITY_H_
#define ABSL_BASE_NULLABILITY_H_
#include "absl/base/internal/nullability_impl.h"
namespace absl {
// absl::Nonnull
//
// The indicated pointer is never null. It is the responsibility of the provider
// of this pointer across an API boundary to ensure that the pointer is never be
// set to null. Consumers of this pointer across an API boundary may safely
// dereference the pointer.
//
// Example:
//
// // `employee` is designated as not null.
// void PaySalary(absl::Nonnull<Employee *> employee) {
// pay(*employee); // OK to dereference
// }
template <typename T>
using Nonnull = nullability_internal::NonnullImpl<T>;
// absl::Nullable
//
// The indicated pointer may, by design, be either null or non-null. Consumers
// of this pointer across an API boundary should perform a `nullptr` check
// before performing any operation using the pointer.
//
// Example:
//
// // `employee` may be null.
// void PaySalary(absl::Nullable<Employee *> employee) {
// if (employee != nullptr) {
// Pay(*employee); // OK to dereference
// }
// }
template <typename T>
using Nullable = nullability_internal::NullableImpl<T>;
// absl::NullabilityUnknown (default)
//
// The indicated pointer has not yet been determined to be definitively
// "non-null" or "nullable." Providers of such pointers across API boundaries
// should, over time, annotate such pointers as either "non-null" or "nullable."
// Consumers of these pointers across an API boundary should treat such pointers
// with the same caution they treat currently unannotated pointers. Most
// existing code will have "unknown" pointers, which should eventually be
// migrated into one of the above two nullability states: `Nonnull<T>` or
// `Nullable<T>`.
//
// NOTE: Because this annotation is the global default state, pointers without
// any annotation are assumed to have "unknown" semantics. This assumption is
// designed to minimize churn and reduce clutter within the codebase.
//
// Example:
//
// // `employee`s nullability state is unknown.
// void PaySalary(absl::NullabilityUnknown<Employee *> employee) {
// Pay(*employee); // Potentially dangerous. API provider should investigate.
// }
//
// Note that a pointer without an annotation, by default, is assumed to have the
// annotation `NullabilityUnknown`.
//
// // `employee`s nullability state is unknown.
// void PaySalary(Employee* employee) {
// Pay(*employee); // Potentially dangerous. API provider should investigate.
// }
template <typename T>
using NullabilityUnknown = nullability_internal::NullabilityUnknownImpl<T>;
} // namespace absl
#endif // ABSL_BASE_NULLABILITY_H_

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//
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: optimization.h
// -----------------------------------------------------------------------------
//
// This header file defines portable macros for performance optimization.
#ifndef ABSL_BASE_OPTIMIZATION_H_
#define ABSL_BASE_OPTIMIZATION_H_
#include <assert.h>
#include "absl/base/config.h"
#include "absl/base/options.h"
// ABSL_BLOCK_TAIL_CALL_OPTIMIZATION
//
// Instructs the compiler to avoid optimizing tail-call recursion. This macro is
// useful when you wish to preserve the existing function order within a stack
// trace for logging, debugging, or profiling purposes.
//
// Example:
//
// int f() {
// int result = g();
// ABSL_BLOCK_TAIL_CALL_OPTIMIZATION();
// return result;
// }
#if defined(__pnacl__)
#define ABSL_BLOCK_TAIL_CALL_OPTIMIZATION() if (volatile int x = 0) { (void)x; }
#elif defined(__clang__)
// Clang will not tail call given inline volatile assembly.
#define ABSL_BLOCK_TAIL_CALL_OPTIMIZATION() __asm__ __volatile__("")
#elif defined(__GNUC__)
// GCC will not tail call given inline volatile assembly.
#define ABSL_BLOCK_TAIL_CALL_OPTIMIZATION() __asm__ __volatile__("")
#elif defined(_MSC_VER)
#include <intrin.h>
// The __nop() intrinsic blocks the optimisation.
#define ABSL_BLOCK_TAIL_CALL_OPTIMIZATION() __nop()
#else
#define ABSL_BLOCK_TAIL_CALL_OPTIMIZATION() if (volatile int x = 0) { (void)x; }
#endif
// ABSL_CACHELINE_SIZE
//
// Explicitly defines the size of the L1 cache for purposes of alignment.
// Setting the cacheline size allows you to specify that certain objects be
// aligned on a cacheline boundary with `ABSL_CACHELINE_ALIGNED` declarations.
// (See below.)
//
// NOTE: this macro should be replaced with the following C++17 features, when
// those are generally available:
//
// * `std::hardware_constructive_interference_size`
// * `std::hardware_destructive_interference_size`
//
// See http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0154r1.html
// for more information.
#if defined(__GNUC__)
// Cache line alignment
#if defined(__i386__) || defined(__x86_64__)
#define ABSL_CACHELINE_SIZE 64
#elif defined(__powerpc64__)
#define ABSL_CACHELINE_SIZE 128
#elif defined(__aarch64__)
// We would need to read special register ctr_el0 to find out L1 dcache size.
// This value is a good estimate based on a real aarch64 machine.
#define ABSL_CACHELINE_SIZE 64
#elif defined(__arm__)
// Cache line sizes for ARM: These values are not strictly correct since
// cache line sizes depend on implementations, not architectures. There
// are even implementations with cache line sizes configurable at boot
// time.
#if defined(__ARM_ARCH_5T__)
#define ABSL_CACHELINE_SIZE 32
#elif defined(__ARM_ARCH_7A__)
#define ABSL_CACHELINE_SIZE 64
#endif
#endif
#endif
#ifndef ABSL_CACHELINE_SIZE
// A reasonable default guess. Note that overestimates tend to waste more
// space, while underestimates tend to waste more time.
#define ABSL_CACHELINE_SIZE 64
#endif
// ABSL_CACHELINE_ALIGNED
//
// Indicates that the declared object be cache aligned using
// `ABSL_CACHELINE_SIZE` (see above). Cacheline aligning objects allows you to
// load a set of related objects in the L1 cache for performance improvements.
// Cacheline aligning objects properly allows constructive memory sharing and
// prevents destructive (or "false") memory sharing.
//
// NOTE: callers should replace uses of this macro with `alignas()` using
// `std::hardware_constructive_interference_size` and/or
// `std::hardware_destructive_interference_size` when C++17 becomes available to
// them.
//
// See http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0154r1.html
// for more information.
//
// On some compilers, `ABSL_CACHELINE_ALIGNED` expands to an `__attribute__`
// or `__declspec` attribute. For compilers where this is not known to work,
// the macro expands to nothing.
//
// No further guarantees are made here. The result of applying the macro
// to variables and types is always implementation-defined.
//
// WARNING: It is easy to use this attribute incorrectly, even to the point
// of causing bugs that are difficult to diagnose, crash, etc. It does not
// of itself guarantee that objects are aligned to a cache line.
//
// NOTE: Some compilers are picky about the locations of annotations such as
// this attribute, so prefer to put it at the beginning of your declaration.
// For example,
//
// ABSL_CACHELINE_ALIGNED static Foo* foo = ...
//
// class ABSL_CACHELINE_ALIGNED Bar { ...
//
// Recommendations:
//
// 1) Consult compiler documentation; this comment is not kept in sync as
// toolchains evolve.
// 2) Verify your use has the intended effect. This often requires inspecting
// the generated machine code.
// 3) Prefer applying this attribute to individual variables. Avoid
// applying it to types. This tends to localize the effect.
#if defined(__clang__) || defined(__GNUC__)
#define ABSL_CACHELINE_ALIGNED __attribute__((aligned(ABSL_CACHELINE_SIZE)))
#elif defined(_MSC_VER)
#define ABSL_CACHELINE_ALIGNED __declspec(align(ABSL_CACHELINE_SIZE))
#else
#define ABSL_CACHELINE_ALIGNED
#endif
// ABSL_PREDICT_TRUE, ABSL_PREDICT_FALSE
//
// Enables the compiler to prioritize compilation using static analysis for
// likely paths within a boolean branch.
//
// Example:
//
// if (ABSL_PREDICT_TRUE(expression)) {
// return result; // Faster if more likely
// } else {
// return 0;
// }
//
// Compilers can use the information that a certain branch is not likely to be
// taken (for instance, a CHECK failure) to optimize for the common case in
// the absence of better information (ie. compiling gcc with `-fprofile-arcs`).
//
// Recommendation: Modern CPUs dynamically predict branch execution paths,
// typically with accuracy greater than 97%. As a result, annotating every
// branch in a codebase is likely counterproductive; however, annotating
// specific branches that are both hot and consistently mispredicted is likely
// to yield performance improvements.
#if ABSL_HAVE_BUILTIN(__builtin_expect) || \
(defined(__GNUC__) && !defined(__clang__))
#define ABSL_PREDICT_FALSE(x) (__builtin_expect(false || (x), false))
#define ABSL_PREDICT_TRUE(x) (__builtin_expect(false || (x), true))
#else
#define ABSL_PREDICT_FALSE(x) (x)
#define ABSL_PREDICT_TRUE(x) (x)
#endif
// `ABSL_INTERNAL_IMMEDIATE_ABORT_IMPL()` aborts the program in the fastest
// possible way, with no attempt at logging. One use is to implement hardening
// aborts with ABSL_OPTION_HARDENED. Since this is an internal symbol, it
// should not be used directly outside of Abseil.
#if ABSL_HAVE_BUILTIN(__builtin_trap) || \
(defined(__GNUC__) && !defined(__clang__))
#define ABSL_INTERNAL_IMMEDIATE_ABORT_IMPL() __builtin_trap()
#else
#define ABSL_INTERNAL_IMMEDIATE_ABORT_IMPL() abort()
#endif
// `ABSL_INTERNAL_UNREACHABLE_IMPL()` is the platform specific directive to
// indicate that a statement is unreachable, and to allow the compiler to
// optimize accordingly. Clients should use `ABSL_UNREACHABLE()`, which is
// defined below.
#if defined(__cpp_lib_unreachable) && __cpp_lib_unreachable >= 202202L
#define ABSL_INTERNAL_UNREACHABLE_IMPL() std::unreachable()
#elif defined(__GNUC__) || ABSL_HAVE_BUILTIN(__builtin_unreachable)
#define ABSL_INTERNAL_UNREACHABLE_IMPL() __builtin_unreachable()
#elif ABSL_HAVE_BUILTIN(__builtin_assume)
#define ABSL_INTERNAL_UNREACHABLE_IMPL() __builtin_assume(false)
#elif defined(_MSC_VER)
#define ABSL_INTERNAL_UNREACHABLE_IMPL() __assume(false)
#else
#define ABSL_INTERNAL_UNREACHABLE_IMPL()
#endif
// `ABSL_UNREACHABLE()` is an unreachable statement. A program which reaches
// one has undefined behavior, and the compiler may optimize accordingly.
#if ABSL_OPTION_HARDENED == 1 && defined(NDEBUG)
// Abort in hardened mode to avoid dangerous undefined behavior.
#define ABSL_UNREACHABLE() \
do { \
ABSL_INTERNAL_IMMEDIATE_ABORT_IMPL(); \
ABSL_INTERNAL_UNREACHABLE_IMPL(); \
} while (false)
#else
// The assert only fires in debug mode to aid in debugging.
// When NDEBUG is defined, reaching ABSL_UNREACHABLE() is undefined behavior.
#define ABSL_UNREACHABLE() \
do { \
/* NOLINTNEXTLINE: misc-static-assert */ \
assert(false && "ABSL_UNREACHABLE reached"); \
ABSL_INTERNAL_UNREACHABLE_IMPL(); \
} while (false)
#endif
// ABSL_ASSUME(cond)
//
// Informs the compiler that a condition is always true and that it can assume
// it to be true for optimization purposes.
//
// WARNING: If the condition is false, the program can produce undefined and
// potentially dangerous behavior.
//
// In !NDEBUG mode, the condition is checked with an assert().
//
// NOTE: The expression must not have side effects, as it may only be evaluated
// in some compilation modes and not others. Some compilers may issue a warning
// if the compiler cannot prove the expression has no side effects. For example,
// the expression should not use a function call since the compiler cannot prove
// that a function call does not have side effects.
//
// Example:
//
// int x = ...;
// ABSL_ASSUME(x >= 0);
// // The compiler can optimize the division to a simple right shift using the
// // assumption specified above.
// int y = x / 16;
//
#if !defined(NDEBUG)
#define ABSL_ASSUME(cond) assert(cond)
#elif ABSL_HAVE_BUILTIN(__builtin_assume)
#define ABSL_ASSUME(cond) __builtin_assume(cond)
#elif defined(_MSC_VER)
#define ABSL_ASSUME(cond) __assume(cond)
#elif defined(__cpp_lib_unreachable) && __cpp_lib_unreachable >= 202202L
#define ABSL_ASSUME(cond) \
do { \
if (!(cond)) std::unreachable(); \
} while (false)
#elif defined(__GNUC__) || ABSL_HAVE_BUILTIN(__builtin_unreachable)
#define ABSL_ASSUME(cond) \
do { \
if (!(cond)) __builtin_unreachable(); \
} while (false)
#else
#define ABSL_ASSUME(cond) \
do { \
static_cast<void>(false && (cond)); \
} while (false)
#endif
// ABSL_INTERNAL_UNIQUE_SMALL_NAME(cond)
// This macro forces small unique name on a static file level symbols like
// static local variables or static functions. This is intended to be used in
// macro definitions to optimize the cost of generated code. Do NOT use it on
// symbols exported from translation unit since it may cause a link time
// conflict.
//
// Example:
//
// #define MY_MACRO(txt)
// namespace {
// char VeryVeryLongVarName[] ABSL_INTERNAL_UNIQUE_SMALL_NAME() = txt;
// const char* VeryVeryLongFuncName() ABSL_INTERNAL_UNIQUE_SMALL_NAME();
// const char* VeryVeryLongFuncName() { return txt; }
// }
//
#if defined(__GNUC__)
#define ABSL_INTERNAL_UNIQUE_SMALL_NAME2(x) #x
#define ABSL_INTERNAL_UNIQUE_SMALL_NAME1(x) ABSL_INTERNAL_UNIQUE_SMALL_NAME2(x)
#define ABSL_INTERNAL_UNIQUE_SMALL_NAME() \
asm(ABSL_INTERNAL_UNIQUE_SMALL_NAME1(.absl.__COUNTER__))
#else
#define ABSL_INTERNAL_UNIQUE_SMALL_NAME()
#endif
#endif // ABSL_BASE_OPTIMIZATION_H_

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// Copyright 2019 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: options.h
// -----------------------------------------------------------------------------
//
// This file contains Abseil configuration options for setting specific
// implementations instead of letting Abseil determine which implementation to
// use at compile-time. Setting these options may be useful for package or build
// managers who wish to guarantee ABI stability within binary builds (which are
// otherwise difficult to enforce).
//
// *** IMPORTANT NOTICE FOR PACKAGE MANAGERS: It is important that
// maintainers of package managers who wish to package Abseil read and
// understand this file! ***
//
// Abseil contains a number of possible configuration endpoints, based on
// parameters such as the detected platform, language version, or command-line
// flags used to invoke the underlying binary. As is the case with all
// libraries, binaries which contain Abseil code must ensure that separate
// packages use the same compiled copy of Abseil to avoid a diamond dependency
// problem, which can occur if two packages built with different Abseil
// configuration settings are linked together. Diamond dependency problems in
// C++ may manifest as violations to the One Definition Rule (ODR) (resulting in
// linker errors), or undefined behavior (resulting in crashes).
//
// Diamond dependency problems can be avoided if all packages utilize the same
// exact version of Abseil. Building from source code with the same compilation
// parameters is the easiest way to avoid such dependency problems. However, for
// package managers who cannot control such compilation parameters, we are
// providing the file to allow you to inject ABI (Application Binary Interface)
// stability across builds. Settings options in this file will neither change
// API nor ABI, providing a stable copy of Abseil between packages.
//
// Care must be taken to keep options within these configurations isolated
// from any other dynamic settings, such as command-line flags which could alter
// these options. This file is provided specifically to help build and package
// managers provide a stable copy of Abseil within their libraries and binaries;
// other developers should not have need to alter the contents of this file.
//
// -----------------------------------------------------------------------------
// Usage
// -----------------------------------------------------------------------------
//
// For any particular package release, set the appropriate definitions within
// this file to whatever value makes the most sense for your package(s). Note
// that, by default, most of these options, at the moment, affect the
// implementation of types; future options may affect other implementation
// details.
//
// NOTE: the defaults within this file all assume that Abseil can select the
// proper Abseil implementation at compile-time, which will not be sufficient
// to guarantee ABI stability to package managers.
#ifndef ABSL_BASE_OPTIONS_H_
#define ABSL_BASE_OPTIONS_H_
// -----------------------------------------------------------------------------
// Type Compatibility Options
// -----------------------------------------------------------------------------
//
// ABSL_OPTION_USE_STD_ANY
//
// This option controls whether absl::any is implemented as an alias to
// std::any, or as an independent implementation.
//
// A value of 0 means to use Abseil's implementation. This requires only C++11
// support, and is expected to work on every toolchain we support.
//
// A value of 1 means to use an alias to std::any. This requires that all code
// using Abseil is built in C++17 mode or later.
//
// A value of 2 means to detect the C++ version being used to compile Abseil,
// and use an alias only if a working std::any is available. This option is
// useful when you are building your entire program, including all of its
// dependencies, from source. It should not be used otherwise -- for example,
// if you are distributing Abseil in a binary package manager -- since in
// mode 2, absl::any will name a different type, with a different mangled name
// and binary layout, depending on the compiler flags passed by the end user.
// For more info, see https://abseil.io/about/design/dropin-types.
//
// User code should not inspect this macro. To check in the preprocessor if
// absl::any is a typedef of std::any, use the feature macro ABSL_USES_STD_ANY.
#define ABSL_OPTION_USE_STD_ANY 1
// ABSL_OPTION_USE_STD_OPTIONAL
//
// This option controls whether absl::optional is implemented as an alias to
// std::optional, or as an independent implementation.
//
// A value of 0 means to use Abseil's implementation. This requires only C++11
// support, and is expected to work on every toolchain we support.
//
// A value of 1 means to use an alias to std::optional. This requires that all
// code using Abseil is built in C++17 mode or later.
//
// A value of 2 means to detect the C++ version being used to compile Abseil,
// and use an alias only if a working std::optional is available. This option
// is useful when you are building your program from source. It should not be
// used otherwise -- for example, if you are distributing Abseil in a binary
// package manager -- since in mode 2, absl::optional will name a different
// type, with a different mangled name and binary layout, depending on the
// compiler flags passed by the end user. For more info, see
// https://abseil.io/about/design/dropin-types.
// User code should not inspect this macro. To check in the preprocessor if
// absl::optional is a typedef of std::optional, use the feature macro
// ABSL_USES_STD_OPTIONAL.
#define ABSL_OPTION_USE_STD_OPTIONAL 1
// ABSL_OPTION_USE_STD_STRING_VIEW
//
// This option controls whether absl::string_view is implemented as an alias to
// std::string_view, or as an independent implementation.
//
// A value of 0 means to use Abseil's implementation. This requires only C++11
// support, and is expected to work on every toolchain we support.
//
// A value of 1 means to use an alias to std::string_view. This requires that
// all code using Abseil is built in C++17 mode or later.
//
// A value of 2 means to detect the C++ version being used to compile Abseil,
// and use an alias only if a working std::string_view is available. This
// option is useful when you are building your program from source. It should
// not be used otherwise -- for example, if you are distributing Abseil in a
// binary package manager -- since in mode 2, absl::string_view will name a
// different type, with a different mangled name and binary layout, depending on
// the compiler flags passed by the end user. For more info, see
// https://abseil.io/about/design/dropin-types.
//
// User code should not inspect this macro. To check in the preprocessor if
// absl::string_view is a typedef of std::string_view, use the feature macro
// ABSL_USES_STD_STRING_VIEW.
#define ABSL_OPTION_USE_STD_STRING_VIEW 1
// ABSL_OPTION_USE_STD_VARIANT
//
// This option controls whether absl::variant is implemented as an alias to
// std::variant, or as an independent implementation.
//
// A value of 0 means to use Abseil's implementation. This requires only C++11
// support, and is expected to work on every toolchain we support.
//
// A value of 1 means to use an alias to std::variant. This requires that all
// code using Abseil is built in C++17 mode or later.
//
// A value of 2 means to detect the C++ version being used to compile Abseil,
// and use an alias only if a working std::variant is available. This option
// is useful when you are building your program from source. It should not be
// used otherwise -- for example, if you are distributing Abseil in a binary
// package manager -- since in mode 2, absl::variant will name a different
// type, with a different mangled name and binary layout, depending on the
// compiler flags passed by the end user. For more info, see
// https://abseil.io/about/design/dropin-types.
//
// User code should not inspect this macro. To check in the preprocessor if
// absl::variant is a typedef of std::variant, use the feature macro
// ABSL_USES_STD_VARIANT.
#define ABSL_OPTION_USE_STD_VARIANT 1
// ABSL_OPTION_USE_STD_ORDERING
//
// This option controls whether absl::{partial,weak,strong}_ordering are
// implemented as aliases to the std:: ordering types, or as an independent
// implementation.
//
// A value of 0 means to use Abseil's implementation. This requires only C++11
// support, and is expected to work on every toolchain we support.
//
// A value of 1 means to use aliases. This requires that all code using Abseil
// is built in C++20 mode or later.
//
// A value of 2 means to detect the C++ version being used to compile Abseil,
// and use an alias only if working std:: ordering types are available. This
// option is useful when you are building your program from source. It should
// not be used otherwise -- for example, if you are distributing Abseil in a
// binary package manager -- since in mode 2, they will name different types,
// with different mangled names and binary layout, depending on the compiler
// flags passed by the end user. For more info, see
// https://abseil.io/about/design/dropin-types.
//
// User code should not inspect this macro. To check in the preprocessor if
// the ordering types are aliases of std:: ordering types, use the feature macro
// ABSL_USES_STD_ORDERING.
#define ABSL_OPTION_USE_STD_ORDERING 1
// ABSL_OPTION_USE_INLINE_NAMESPACE
// ABSL_OPTION_INLINE_NAMESPACE_NAME
//
// These options controls whether all entities in the absl namespace are
// contained within an inner inline namespace. This does not affect the
// user-visible API of Abseil, but it changes the mangled names of all symbols.
//
// This can be useful as a version tag if you are distributing Abseil in
// precompiled form. This will prevent a binary library build of Abseil with
// one inline namespace being used with headers configured with a different
// inline namespace name. Binary packagers are reminded that Abseil does not
// guarantee any ABI stability in Abseil, so any update of Abseil or
// configuration change in such a binary package should be combined with a
// new, unique value for the inline namespace name.
//
// A value of 0 means not to use inline namespaces.
//
// A value of 1 means to use an inline namespace with the given name inside
// namespace absl. If this is set, ABSL_OPTION_INLINE_NAMESPACE_NAME must also
// be changed to a new, unique identifier name. In particular "head" is not
// allowed.
#define ABSL_OPTION_USE_INLINE_NAMESPACE 0
#define ABSL_OPTION_INLINE_NAMESPACE_NAME head
// ABSL_OPTION_HARDENED
//
// This option enables a "hardened" build in release mode (in this context,
// release mode is defined as a build where the `NDEBUG` macro is defined).
//
// A value of 0 means that "hardened" mode is not enabled.
//
// A value of 1 means that "hardened" mode is enabled.
//
// Hardened builds have additional security checks enabled when `NDEBUG` is
// defined. Defining `NDEBUG` is normally used to turn `assert()` macro into a
// no-op, as well as disabling other bespoke program consistency checks. By
// defining ABSL_OPTION_HARDENED to 1, a select set of checks remain enabled in
// release mode. These checks guard against programming errors that may lead to
// security vulnerabilities. In release mode, when one of these programming
// errors is encountered, the program will immediately abort, possibly without
// any attempt at logging.
//
// The checks enabled by this option are not free; they do incur runtime cost.
//
// The checks enabled by this option are always active when `NDEBUG` is not
// defined, even in the case when ABSL_OPTION_HARDENED is defined to 0. The
// checks enabled by this option may abort the program in a different way and
// log additional information when `NDEBUG` is not defined.
#define ABSL_OPTION_HARDENED 0
#endif // ABSL_BASE_OPTIONS_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: policy_checks.h
// -----------------------------------------------------------------------------
//
// This header enforces a minimum set of policies at build time, such as the
// supported compiler and library versions. Unsupported configurations are
// reported with `#error`. This enforcement is best effort, so successfully
// compiling this header does not guarantee a supported configuration.
#ifndef ABSL_BASE_POLICY_CHECKS_H_
#define ABSL_BASE_POLICY_CHECKS_H_
// Included for the __GLIBC_PREREQ macro used below.
#include <limits.h>
// Included for the _STLPORT_VERSION macro used below.
#if defined(__cplusplus)
#include <cstddef>
#endif
// -----------------------------------------------------------------------------
// Operating System Check
// -----------------------------------------------------------------------------
#if defined(__CYGWIN__)
#error "Cygwin is not supported."
#endif
// -----------------------------------------------------------------------------
// Toolchain Check
// -----------------------------------------------------------------------------
// We support Visual Studio 2019 (MSVC++ 16.0) and later.
// This minimum will go up.
#if defined(_MSC_VER) && _MSC_VER < 1920 && !defined(__clang__)
#error "This package requires Visual Studio 2019 (MSVC++ 16.0) or higher."
#endif
// We support GCC 7 and later.
// This minimum will go up.
#if defined(__GNUC__) && !defined(__clang__)
#if __GNUC__ < 7
#error "This package requires GCC 7 or higher."
#endif
#endif
// We support Apple Xcode clang 4.2.1 (version 421.11.65) and later.
// This corresponds to Apple Xcode version 4.5.
// This minimum will go up.
#if defined(__apple_build_version__) && __apple_build_version__ < 4211165
#error "This package requires __apple_build_version__ of 4211165 or higher."
#endif
// -----------------------------------------------------------------------------
// C++ Version Check
// -----------------------------------------------------------------------------
// Enforce C++14 as the minimum.
#if defined(_MSVC_LANG)
#if _MSVC_LANG < 201402L
#error "C++ versions less than C++14 are not supported."
#endif // _MSVC_LANG < 201402L
#elif defined(__cplusplus)
#if __cplusplus < 201402L
#error "C++ versions less than C++14 are not supported."
#endif // __cplusplus < 201402L
#endif
// -----------------------------------------------------------------------------
// Standard Library Check
// -----------------------------------------------------------------------------
#if defined(_STLPORT_VERSION)
#error "STLPort is not supported."
#endif
// -----------------------------------------------------------------------------
// `char` Size Check
// -----------------------------------------------------------------------------
// Abseil currently assumes CHAR_BIT == 8. If you would like to use Abseil on a
// platform where this is not the case, please provide us with the details about
// your platform so we can consider relaxing this requirement.
#if CHAR_BIT != 8
#error "Abseil assumes CHAR_BIT == 8."
#endif
// -----------------------------------------------------------------------------
// `int` Size Check
// -----------------------------------------------------------------------------
// Abseil currently assumes that an int is 4 bytes. If you would like to use
// Abseil on a platform where this is not the case, please provide us with the
// details about your platform so we can consider relaxing this requirement.
#if INT_MAX < 2147483647
#error "Abseil assumes that int is at least 4 bytes. "
#endif
#endif // ABSL_BASE_POLICY_CHECKS_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// This files is a forwarding header for other headers containing various
// portability macros and functions.
#ifndef ABSL_BASE_PORT_H_
#define ABSL_BASE_PORT_H_
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#include "absl/base/optimization.h"
#endif // ABSL_BASE_PORT_H_

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// Copyright 2023 The Abseil Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: prefetch.h
// -----------------------------------------------------------------------------
//
// This header file defines prefetch functions to prefetch memory contents
// into the first level cache (L1) for the current CPU. The prefetch logic
// offered in this header is limited to prefetching first level cachelines
// only, and is aimed at relatively 'simple' prefetching logic.
//
#ifndef ABSL_BASE_PREFETCH_H_
#define ABSL_BASE_PREFETCH_H_
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#if defined(ABSL_INTERNAL_HAVE_SSE)
#include <xmmintrin.h>
#endif
#if defined(_MSC_VER)
#include <intrin.h>
#if defined(ABSL_INTERNAL_HAVE_SSE)
#pragma intrinsic(_mm_prefetch)
#endif
#endif
namespace absl {
ABSL_NAMESPACE_BEGIN
// Moves data into the L1 cache before it is read, or "prefetches" it.
//
// The value of `addr` is the address of the memory to prefetch. If
// the target and compiler support it, data prefetch instructions are
// generated. If the prefetch is done some time before the memory is
// read, it may be in the cache by the time the read occurs.
//
// This method prefetches data with the highest degree of temporal locality;
// data is prefetched where possible into all levels of the cache.
//
// Incorrect or gratuitous use of this function can degrade performance.
// Use this function only when representative benchmarks show an improvement.
//
// Example:
//
// // Computes incremental checksum for `data`.
// int ComputeChecksum(int sum, absl::string_view data);
//
// // Computes cumulative checksum for all values in `data`
// int ComputeChecksum(absl::Span<const std::string> data) {
// int sum = 0;
// auto it = data.begin();
// auto pit = data.begin();
// auto end = data.end();
// for (int dist = 8; dist > 0 && pit != data.end(); --dist, ++pit) {
// absl::PrefetchToLocalCache(pit->data());
// }
// for (; pit != end; ++pit, ++it) {
// sum = ComputeChecksum(sum, *it);
// absl::PrefetchToLocalCache(pit->data());
// }
// for (; it != end; ++it) {
// sum = ComputeChecksum(sum, *it);
// }
// return sum;
// }
//
void PrefetchToLocalCache(const void* addr);
// Moves data into the L1 cache before it is read, or "prefetches" it.
//
// This function is identical to `PrefetchToLocalCache()` except that it has
// non-temporal locality: the fetched data should not be left in any of the
// cache tiers. This is useful for cases where the data is used only once /
// short term, for example, invoking a destructor on an object.
//
// Incorrect or gratuitous use of this function can degrade performance.
// Use this function only when representative benchmarks show an improvement.
//
// Example:
//
// template <typename Iterator>
// void DestroyPointers(Iterator begin, Iterator end) {
// size_t distance = std::min(8U, bars.size());
//
// int dist = 8;
// auto prefetch_it = begin;
// while (prefetch_it != end && --dist;) {
// absl::PrefetchToLocalCacheNta(*prefetch_it++);
// }
// while (prefetch_it != end) {
// delete *begin++;
// absl::PrefetchToLocalCacheNta(*prefetch_it++);
// }
// while (begin != end) {
// delete *begin++;
// }
// }
//
void PrefetchToLocalCacheNta(const void* addr);
// Moves data into the L1 cache with the intent to modify it.
//
// This function is similar to `PrefetchToLocalCache()` except that it
// prefetches cachelines with an 'intent to modify' This typically includes
// invalidating cache entries for this address in all other cache tiers, and an
// exclusive access intent.
//
// Incorrect or gratuitous use of this function can degrade performance. As this
// function can invalidate cached cachelines on other caches and computer cores,
// incorrect usage of this function can have an even greater negative impact
// than incorrect regular prefetches.
// Use this function only when representative benchmarks show an improvement.
//
// Example:
//
// void* Arena::Allocate(size_t size) {
// void* ptr = AllocateBlock(size);
// absl::PrefetchToLocalCacheForWrite(p);
// return ptr;
// }
//
void PrefetchToLocalCacheForWrite(const void* addr);
#if ABSL_HAVE_BUILTIN(__builtin_prefetch) || defined(__GNUC__)
#define ABSL_HAVE_PREFETCH 1
// See __builtin_prefetch:
// https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html.
//
ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCache(
const void* addr) {
__builtin_prefetch(addr, 0, 3);
}
ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheNta(
const void* addr) {
__builtin_prefetch(addr, 0, 0);
}
ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheForWrite(
const void* addr) {
// [x86] gcc/clang don't generate PREFETCHW for __builtin_prefetch(.., 1)
// unless -march=broadwell or newer; this is not generally the default, so we
// manually emit prefetchw. PREFETCHW is recognized as a no-op on older Intel
// processors and has been present on AMD processors since the K6-2.
#if defined(__x86_64__) && !defined(__PRFCHW__)
asm("prefetchw %0" : : "m"(*reinterpret_cast<const char*>(addr)));
#else
__builtin_prefetch(addr, 1, 3);
#endif
}
#elif defined(ABSL_INTERNAL_HAVE_SSE)
#define ABSL_HAVE_PREFETCH 1
ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCache(
const void* addr) {
_mm_prefetch(reinterpret_cast<const char*>(addr), _MM_HINT_T0);
}
ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheNta(
const void* addr) {
_mm_prefetch(reinterpret_cast<const char*>(addr), _MM_HINT_NTA);
}
ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheForWrite(
const void* addr) {
#if defined(_MM_HINT_ET0)
_mm_prefetch(reinterpret_cast<const char*>(addr), _MM_HINT_ET0);
#elif !defined(_MSC_VER) && defined(__x86_64__)
// _MM_HINT_ET0 is not universally supported. As we commented further
// up, PREFETCHW is recognized as a no-op on older Intel processors
// and has been present on AMD processors since the K6-2. We have this
// disabled for MSVC compilers as this miscompiles on older MSVC compilers.
asm("prefetchw %0" : : "m"(*reinterpret_cast<const char*>(addr)));
#endif
}
#else
ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCache(
const void* addr) {}
ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheNta(
const void* addr) {}
ABSL_ATTRIBUTE_ALWAYS_INLINE inline void PrefetchToLocalCacheForWrite(
const void* addr) {}
#endif
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_PREFETCH_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: thread_annotations.h
// -----------------------------------------------------------------------------
//
// This header file contains macro definitions for thread safety annotations
// that allow developers to document the locking policies of multi-threaded
// code. The annotations can also help program analysis tools to identify
// potential thread safety issues.
//
// These annotations are implemented using compiler attributes. Using the macros
// defined here instead of raw attributes allow for portability and future
// compatibility.
//
// When referring to mutexes in the arguments of the attributes, you should
// use variable names or more complex expressions (e.g. my_object->mutex_)
// that evaluate to a concrete mutex object whenever possible. If the mutex
// you want to refer to is not in scope, you may use a member pointer
// (e.g. &MyClass::mutex_) to refer to a mutex in some (unknown) object.
#ifndef ABSL_BASE_THREAD_ANNOTATIONS_H_
#define ABSL_BASE_THREAD_ANNOTATIONS_H_
#include "absl/base/attributes.h"
#include "absl/base/config.h"
// ABSL_GUARDED_BY()
//
// Documents if a shared field or global variable needs to be protected by a
// mutex. ABSL_GUARDED_BY() allows the user to specify a particular mutex that
// should be held when accessing the annotated variable.
//
// Although this annotation (and ABSL_PT_GUARDED_BY, below) cannot be applied to
// local variables, a local variable and its associated mutex can often be
// combined into a small class or struct, thereby allowing the annotation.
//
// Example:
//
// class Foo {
// Mutex mu_;
// int p1_ ABSL_GUARDED_BY(mu_);
// ...
// };
#if ABSL_HAVE_ATTRIBUTE(guarded_by)
#define ABSL_GUARDED_BY(x) __attribute__((guarded_by(x)))
#else
#define ABSL_GUARDED_BY(x)
#endif
// ABSL_PT_GUARDED_BY()
//
// Documents if the memory location pointed to by a pointer should be guarded
// by a mutex when dereferencing the pointer.
//
// Example:
// class Foo {
// Mutex mu_;
// int *p1_ ABSL_PT_GUARDED_BY(mu_);
// ...
// };
//
// Note that a pointer variable to a shared memory location could itself be a
// shared variable.
//
// Example:
//
// // `q_`, guarded by `mu1_`, points to a shared memory location that is
// // guarded by `mu2_`:
// int *q_ ABSL_GUARDED_BY(mu1_) ABSL_PT_GUARDED_BY(mu2_);
#if ABSL_HAVE_ATTRIBUTE(pt_guarded_by)
#define ABSL_PT_GUARDED_BY(x) __attribute__((pt_guarded_by(x)))
#else
#define ABSL_PT_GUARDED_BY(x)
#endif
// ABSL_ACQUIRED_AFTER() / ABSL_ACQUIRED_BEFORE()
//
// Documents the acquisition order between locks that can be held
// simultaneously by a thread. For any two locks that need to be annotated
// to establish an acquisition order, only one of them needs the annotation.
// (i.e. You don't have to annotate both locks with both ABSL_ACQUIRED_AFTER
// and ABSL_ACQUIRED_BEFORE.)
//
// As with ABSL_GUARDED_BY, this is only applicable to mutexes that are shared
// fields or global variables.
//
// Example:
//
// Mutex m1_;
// Mutex m2_ ABSL_ACQUIRED_AFTER(m1_);
#if ABSL_HAVE_ATTRIBUTE(acquired_after)
#define ABSL_ACQUIRED_AFTER(...) __attribute__((acquired_after(__VA_ARGS__)))
#else
#define ABSL_ACQUIRED_AFTER(...)
#endif
#if ABSL_HAVE_ATTRIBUTE(acquired_before)
#define ABSL_ACQUIRED_BEFORE(...) __attribute__((acquired_before(__VA_ARGS__)))
#else
#define ABSL_ACQUIRED_BEFORE(...)
#endif
// ABSL_EXCLUSIVE_LOCKS_REQUIRED() / ABSL_SHARED_LOCKS_REQUIRED()
//
// Documents a function that expects a mutex to be held prior to entry.
// The mutex is expected to be held both on entry to, and exit from, the
// function.
//
// An exclusive lock allows read-write access to the guarded data member(s), and
// only one thread can acquire a lock exclusively at any one time. A shared lock
// allows read-only access, and any number of threads can acquire a shared lock
// concurrently.
//
// Generally, non-const methods should be annotated with
// ABSL_EXCLUSIVE_LOCKS_REQUIRED, while const methods should be annotated with
// ABSL_SHARED_LOCKS_REQUIRED.
//
// Example:
//
// Mutex mu1, mu2;
// int a ABSL_GUARDED_BY(mu1);
// int b ABSL_GUARDED_BY(mu2);
//
// void foo() ABSL_EXCLUSIVE_LOCKS_REQUIRED(mu1, mu2) { ... }
// void bar() const ABSL_SHARED_LOCKS_REQUIRED(mu1, mu2) { ... }
#if ABSL_HAVE_ATTRIBUTE(exclusive_locks_required)
#define ABSL_EXCLUSIVE_LOCKS_REQUIRED(...) \
__attribute__((exclusive_locks_required(__VA_ARGS__)))
#else
#define ABSL_EXCLUSIVE_LOCKS_REQUIRED(...)
#endif
#if ABSL_HAVE_ATTRIBUTE(shared_locks_required)
#define ABSL_SHARED_LOCKS_REQUIRED(...) \
__attribute__((shared_locks_required(__VA_ARGS__)))
#else
#define ABSL_SHARED_LOCKS_REQUIRED(...)
#endif
// ABSL_LOCKS_EXCLUDED()
//
// Documents the locks that cannot be held by callers of this function, as they
// might be acquired by this function (Abseil's `Mutex` locks are
// non-reentrant).
#if ABSL_HAVE_ATTRIBUTE(locks_excluded)
#define ABSL_LOCKS_EXCLUDED(...) __attribute__((locks_excluded(__VA_ARGS__)))
#else
#define ABSL_LOCKS_EXCLUDED(...)
#endif
// ABSL_LOCK_RETURNED()
//
// Documents a function that returns a mutex without acquiring it. For example,
// a public getter method that returns a pointer to a private mutex should
// be annotated with ABSL_LOCK_RETURNED.
#if ABSL_HAVE_ATTRIBUTE(lock_returned)
#define ABSL_LOCK_RETURNED(x) __attribute__((lock_returned(x)))
#else
#define ABSL_LOCK_RETURNED(x)
#endif
// ABSL_LOCKABLE
//
// Documents if a class/type is a lockable type (such as the `Mutex` class).
#if ABSL_HAVE_ATTRIBUTE(lockable)
#define ABSL_LOCKABLE __attribute__((lockable))
#else
#define ABSL_LOCKABLE
#endif
// ABSL_SCOPED_LOCKABLE
//
// Documents if a class does RAII locking (such as the `MutexLock` class).
// The constructor should use `LOCK_FUNCTION()` to specify the mutex that is
// acquired, and the destructor should use `UNLOCK_FUNCTION()` with no
// arguments; the analysis will assume that the destructor unlocks whatever the
// constructor locked.
#if ABSL_HAVE_ATTRIBUTE(scoped_lockable)
#define ABSL_SCOPED_LOCKABLE __attribute__((scoped_lockable))
#else
#define ABSL_SCOPED_LOCKABLE
#endif
// ABSL_EXCLUSIVE_LOCK_FUNCTION()
//
// Documents functions that acquire a lock in the body of a function, and do
// not release it.
#if ABSL_HAVE_ATTRIBUTE(exclusive_lock_function)
#define ABSL_EXCLUSIVE_LOCK_FUNCTION(...) \
__attribute__((exclusive_lock_function(__VA_ARGS__)))
#else
#define ABSL_EXCLUSIVE_LOCK_FUNCTION(...)
#endif
// ABSL_SHARED_LOCK_FUNCTION()
//
// Documents functions that acquire a shared (reader) lock in the body of a
// function, and do not release it.
#if ABSL_HAVE_ATTRIBUTE(shared_lock_function)
#define ABSL_SHARED_LOCK_FUNCTION(...) \
__attribute__((shared_lock_function(__VA_ARGS__)))
#else
#define ABSL_SHARED_LOCK_FUNCTION(...)
#endif
// ABSL_UNLOCK_FUNCTION()
//
// Documents functions that expect a lock to be held on entry to the function,
// and release it in the body of the function.
#if ABSL_HAVE_ATTRIBUTE(unlock_function)
#define ABSL_UNLOCK_FUNCTION(...) __attribute__((unlock_function(__VA_ARGS__)))
#else
#define ABSL_UNLOCK_FUNCTION(...)
#endif
// ABSL_EXCLUSIVE_TRYLOCK_FUNCTION() / ABSL_SHARED_TRYLOCK_FUNCTION()
//
// Documents functions that try to acquire a lock, and return success or failure
// (or a non-boolean value that can be interpreted as a boolean).
// The first argument should be `true` for functions that return `true` on
// success, or `false` for functions that return `false` on success. The second
// argument specifies the mutex that is locked on success. If unspecified, this
// mutex is assumed to be `this`.
#if ABSL_HAVE_ATTRIBUTE(exclusive_trylock_function)
#define ABSL_EXCLUSIVE_TRYLOCK_FUNCTION(...) \
__attribute__((exclusive_trylock_function(__VA_ARGS__)))
#else
#define ABSL_EXCLUSIVE_TRYLOCK_FUNCTION(...)
#endif
#if ABSL_HAVE_ATTRIBUTE(shared_trylock_function)
#define ABSL_SHARED_TRYLOCK_FUNCTION(...) \
__attribute__((shared_trylock_function(__VA_ARGS__)))
#else
#define ABSL_SHARED_TRYLOCK_FUNCTION(...)
#endif
// ABSL_ASSERT_EXCLUSIVE_LOCK() / ABSL_ASSERT_SHARED_LOCK()
//
// Documents functions that dynamically check to see if a lock is held, and fail
// if it is not held.
#if ABSL_HAVE_ATTRIBUTE(assert_exclusive_lock)
#define ABSL_ASSERT_EXCLUSIVE_LOCK(...) \
__attribute__((assert_exclusive_lock(__VA_ARGS__)))
#else
#define ABSL_ASSERT_EXCLUSIVE_LOCK(...)
#endif
#if ABSL_HAVE_ATTRIBUTE(assert_shared_lock)
#define ABSL_ASSERT_SHARED_LOCK(...) \
__attribute__((assert_shared_lock(__VA_ARGS__)))
#else
#define ABSL_ASSERT_SHARED_LOCK(...)
#endif
// ABSL_NO_THREAD_SAFETY_ANALYSIS
//
// Turns off thread safety checking within the body of a particular function.
// This annotation is used to mark functions that are known to be correct, but
// the locking behavior is more complicated than the analyzer can handle.
#if ABSL_HAVE_ATTRIBUTE(no_thread_safety_analysis)
#define ABSL_NO_THREAD_SAFETY_ANALYSIS \
__attribute__((no_thread_safety_analysis))
#else
#define ABSL_NO_THREAD_SAFETY_ANALYSIS
#endif
//------------------------------------------------------------------------------
// Tool-Supplied Annotations
//------------------------------------------------------------------------------
// ABSL_TS_UNCHECKED should be placed around lock expressions that are not valid
// C++ syntax, but which are present for documentation purposes. These
// annotations will be ignored by the analysis.
#define ABSL_TS_UNCHECKED(x) ""
// ABSL_TS_FIXME is used to mark lock expressions that are not valid C++ syntax.
// It is used by automated tools to mark and disable invalid expressions.
// The annotation should either be fixed, or changed to ABSL_TS_UNCHECKED.
#define ABSL_TS_FIXME(x) ""
// Like ABSL_NO_THREAD_SAFETY_ANALYSIS, this turns off checking within the body
// of a particular function. However, this attribute is used to mark functions
// that are incorrect and need to be fixed. It is used by automated tools to
// avoid breaking the build when the analysis is updated.
// Code owners are expected to eventually fix the routine.
#define ABSL_NO_THREAD_SAFETY_ANALYSIS_FIXME ABSL_NO_THREAD_SAFETY_ANALYSIS
// Similar to ABSL_NO_THREAD_SAFETY_ANALYSIS_FIXME, this macro marks a
// ABSL_GUARDED_BY annotation that needs to be fixed, because it is producing
// thread safety warning. It disables the ABSL_GUARDED_BY.
#define ABSL_GUARDED_BY_FIXME(x)
// Disables warnings for a single read operation. This can be used to avoid
// warnings when it is known that the read is not actually involved in a race,
// but the compiler cannot confirm that.
#define ABSL_TS_UNCHECKED_READ(x) absl::base_internal::ts_unchecked_read(x)
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
// Takes a reference to a guarded data member, and returns an unguarded
// reference.
// Do not use this function directly, use ABSL_TS_UNCHECKED_READ instead.
template <typename T>
inline const T& ts_unchecked_read(const T& v) ABSL_NO_THREAD_SAFETY_ANALYSIS {
return v;
}
template <typename T>
inline T& ts_unchecked_read(T& v) ABSL_NO_THREAD_SAFETY_ANALYSIS {
return v;
}
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_THREAD_ANNOTATIONS_H_

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// Copyright 2021 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: cleanup.h
// -----------------------------------------------------------------------------
//
// `absl::Cleanup` implements the scope guard idiom, invoking the contained
// callback's `operator()() &&` on scope exit.
//
// Example:
//
// ```
// absl::Status CopyGoodData(const char* source_path, const char* sink_path) {
// FILE* source_file = fopen(source_path, "r");
// if (source_file == nullptr) {
// return absl::NotFoundError("No source file"); // No cleanups execute
// }
//
// // C++17 style cleanup using class template argument deduction
// absl::Cleanup source_closer = [source_file] { fclose(source_file); };
//
// FILE* sink_file = fopen(sink_path, "w");
// if (sink_file == nullptr) {
// return absl::NotFoundError("No sink file"); // First cleanup executes
// }
//
// // C++11 style cleanup using the factory function
// auto sink_closer = absl::MakeCleanup([sink_file] { fclose(sink_file); });
//
// Data data;
// while (ReadData(source_file, &data)) {
// if (!data.IsGood()) {
// absl::Status result = absl::FailedPreconditionError("Read bad data");
// return result; // Both cleanups execute
// }
// SaveData(sink_file, &data);
// }
//
// return absl::OkStatus(); // Both cleanups execute
// }
// ```
//
// Methods:
//
// `std::move(cleanup).Cancel()` will prevent the callback from executing.
//
// `std::move(cleanup).Invoke()` will execute the callback early, before
// destruction, and prevent the callback from executing in the destructor.
//
// Usage:
//
// `absl::Cleanup` is not an interface type. It is only intended to be used
// within the body of a function. It is not a value type and instead models a
// control flow construct. Check out `defer` in Golang for something similar.
#ifndef ABSL_CLEANUP_CLEANUP_H_
#define ABSL_CLEANUP_CLEANUP_H_
#include <utility>
#include "absl/base/config.h"
#include "absl/base/macros.h"
#include "absl/cleanup/internal/cleanup.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
template <typename Arg, typename Callback = void()>
class ABSL_MUST_USE_RESULT Cleanup final {
static_assert(cleanup_internal::WasDeduced<Arg>(),
"Explicit template parameters are not supported.");
static_assert(cleanup_internal::ReturnsVoid<Callback>(),
"Callbacks that return values are not supported.");
public:
Cleanup(Callback callback) : storage_(std::move(callback)) {} // NOLINT
Cleanup(Cleanup&& other) = default;
void Cancel() && {
ABSL_HARDENING_ASSERT(storage_.IsCallbackEngaged());
storage_.DestroyCallback();
}
void Invoke() && {
ABSL_HARDENING_ASSERT(storage_.IsCallbackEngaged());
storage_.InvokeCallback();
storage_.DestroyCallback();
}
~Cleanup() {
if (storage_.IsCallbackEngaged()) {
storage_.InvokeCallback();
storage_.DestroyCallback();
}
}
private:
cleanup_internal::Storage<Callback> storage_;
};
// `absl::Cleanup c = /* callback */;`
//
// C++17 type deduction API for creating an instance of `absl::Cleanup`
#if defined(ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION)
template <typename Callback>
Cleanup(Callback callback) -> Cleanup<cleanup_internal::Tag, Callback>;
#endif // defined(ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION)
// `auto c = absl::MakeCleanup(/* callback */);`
//
// C++11 type deduction API for creating an instance of `absl::Cleanup`
template <typename... Args, typename Callback>
absl::Cleanup<cleanup_internal::Tag, Callback> MakeCleanup(Callback callback) {
static_assert(cleanup_internal::WasDeduced<cleanup_internal::Tag, Args...>(),
"Explicit template parameters are not supported.");
static_assert(cleanup_internal::ReturnsVoid<Callback>(),
"Callbacks that return values are not supported.");
return {std::move(callback)};
}
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CLEANUP_CLEANUP_H_

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// Copyright 2021 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CLEANUP_INTERNAL_CLEANUP_H_
#define ABSL_CLEANUP_INTERNAL_CLEANUP_H_
#include <new>
#include <type_traits>
#include <utility>
#include "absl/base/internal/invoke.h"
#include "absl/base/macros.h"
#include "absl/base/thread_annotations.h"
#include "absl/utility/utility.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace cleanup_internal {
struct Tag {};
template <typename Arg, typename... Args>
constexpr bool WasDeduced() {
return (std::is_same<cleanup_internal::Tag, Arg>::value) &&
(sizeof...(Args) == 0);
}
template <typename Callback>
constexpr bool ReturnsVoid() {
return (std::is_same<base_internal::invoke_result_t<Callback>, void>::value);
}
template <typename Callback>
class Storage {
public:
Storage() = delete;
explicit Storage(Callback callback) {
// Placement-new into a character buffer is used for eager destruction when
// the cleanup is invoked or cancelled. To ensure this optimizes well, the
// behavior is implemented locally instead of using an absl::optional.
::new (GetCallbackBuffer()) Callback(std::move(callback));
is_callback_engaged_ = true;
}
Storage(Storage&& other) {
ABSL_HARDENING_ASSERT(other.IsCallbackEngaged());
::new (GetCallbackBuffer()) Callback(std::move(other.GetCallback()));
is_callback_engaged_ = true;
other.DestroyCallback();
}
Storage(const Storage& other) = delete;
Storage& operator=(Storage&& other) = delete;
Storage& operator=(const Storage& other) = delete;
void* GetCallbackBuffer() { return static_cast<void*>(+callback_buffer_); }
Callback& GetCallback() {
return *reinterpret_cast<Callback*>(GetCallbackBuffer());
}
bool IsCallbackEngaged() const { return is_callback_engaged_; }
void DestroyCallback() {
is_callback_engaged_ = false;
GetCallback().~Callback();
}
void InvokeCallback() ABSL_NO_THREAD_SAFETY_ANALYSIS {
std::move(GetCallback())();
}
private:
bool is_callback_engaged_;
alignas(Callback) char callback_buffer_[sizeof(Callback)];
};
} // namespace cleanup_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CLEANUP_INTERNAL_CLEANUP_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: btree_map.h
// -----------------------------------------------------------------------------
//
// This header file defines B-tree maps: sorted associative containers mapping
// keys to values.
//
// * `absl::btree_map<>`
// * `absl::btree_multimap<>`
//
// These B-tree types are similar to the corresponding types in the STL
// (`std::map` and `std::multimap`) and generally conform to the STL interfaces
// of those types. However, because they are implemented using B-trees, they
// are more efficient in most situations.
//
// Unlike `std::map` and `std::multimap`, which are commonly implemented using
// red-black tree nodes, B-tree maps use more generic B-tree nodes able to hold
// multiple values per node. Holding multiple values per node often makes
// B-tree maps perform better than their `std::map` counterparts, because
// multiple entries can be checked within the same cache hit.
//
// However, these types should not be considered drop-in replacements for
// `std::map` and `std::multimap` as there are some API differences, which are
// noted in this header file. The most consequential differences with respect to
// migrating to b-tree from the STL types are listed in the next paragraph.
// Other API differences are minor.
//
// Importantly, insertions and deletions may invalidate outstanding iterators,
// pointers, and references to elements. Such invalidations are typically only
// an issue if insertion and deletion operations are interleaved with the use of
// more than one iterator, pointer, or reference simultaneously. For this
// reason, `insert()`, `erase()`, and `extract_and_get_next()` return a valid
// iterator at the current position. Another important difference is that
// key-types must be copy-constructible.
//
// Another API difference is that btree iterators can be subtracted, and this
// is faster than using std::distance.
#ifndef ABSL_CONTAINER_BTREE_MAP_H_
#define ABSL_CONTAINER_BTREE_MAP_H_
#include "absl/base/attributes.h"
#include "absl/container/internal/btree.h" // IWYU pragma: export
#include "absl/container/internal/btree_container.h" // IWYU pragma: export
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <typename Key, typename Data, typename Compare, typename Alloc,
int TargetNodeSize, bool IsMulti>
struct map_params;
} // namespace container_internal
// absl::btree_map<>
//
// An `absl::btree_map<K, V>` is an ordered associative container of
// unique keys and associated values designed to be a more efficient replacement
// for `std::map` (in most cases).
//
// Keys are sorted using an (optional) comparison function, which defaults to
// `std::less<K>`.
//
// An `absl::btree_map<K, V>` uses a default allocator of
// `std::allocator<std::pair<const K, V>>` to allocate (and deallocate)
// nodes, and construct and destruct values within those nodes. You may
// instead specify a custom allocator `A` (which in turn requires specifying a
// custom comparator `C`) as in `absl::btree_map<K, V, C, A>`.
//
template <typename Key, typename Value, typename Compare = std::less<Key>,
typename Alloc = std::allocator<std::pair<const Key, Value>>>
class btree_map
: public container_internal::btree_map_container<
container_internal::btree<container_internal::map_params<
Key, Value, Compare, Alloc, /*TargetNodeSize=*/256,
/*IsMulti=*/false>>> {
using Base = typename btree_map::btree_map_container;
public:
// Constructors and Assignment Operators
//
// A `btree_map` supports the same overload set as `std::map`
// for construction and assignment:
//
// * Default constructor
//
// absl::btree_map<int, std::string> map1;
//
// * Initializer List constructor
//
// absl::btree_map<int, std::string> map2 =
// {{1, "huey"}, {2, "dewey"}, {3, "louie"},};
//
// * Copy constructor
//
// absl::btree_map<int, std::string> map3(map2);
//
// * Copy assignment operator
//
// absl::btree_map<int, std::string> map4;
// map4 = map3;
//
// * Move constructor
//
// // Move is guaranteed efficient
// absl::btree_map<int, std::string> map5(std::move(map4));
//
// * Move assignment operator
//
// // May be efficient if allocators are compatible
// absl::btree_map<int, std::string> map6;
// map6 = std::move(map5);
//
// * Range constructor
//
// std::vector<std::pair<int, std::string>> v = {{1, "a"}, {2, "b"}};
// absl::btree_map<int, std::string> map7(v.begin(), v.end());
btree_map() {}
using Base::Base;
// btree_map::begin()
//
// Returns an iterator to the beginning of the `btree_map`.
using Base::begin;
// btree_map::cbegin()
//
// Returns a const iterator to the beginning of the `btree_map`.
using Base::cbegin;
// btree_map::end()
//
// Returns an iterator to the end of the `btree_map`.
using Base::end;
// btree_map::cend()
//
// Returns a const iterator to the end of the `btree_map`.
using Base::cend;
// btree_map::empty()
//
// Returns whether or not the `btree_map` is empty.
using Base::empty;
// btree_map::max_size()
//
// Returns the largest theoretical possible number of elements within a
// `btree_map` under current memory constraints. This value can be thought
// of as the largest value of `std::distance(begin(), end())` for a
// `btree_map<Key, T>`.
using Base::max_size;
// btree_map::size()
//
// Returns the number of elements currently within the `btree_map`.
using Base::size;
// btree_map::clear()
//
// Removes all elements from the `btree_map`. Invalidates any references,
// pointers, or iterators referring to contained elements.
using Base::clear;
// btree_map::erase()
//
// Erases elements within the `btree_map`. If an erase occurs, any references,
// pointers, or iterators are invalidated.
// Overloads are listed below.
//
// iterator erase(iterator position):
// iterator erase(const_iterator position):
//
// Erases the element at `position` of the `btree_map`, returning
// the iterator pointing to the element after the one that was erased
// (or end() if none exists).
//
// iterator erase(const_iterator first, const_iterator last):
//
// Erases the elements in the open interval [`first`, `last`), returning
// the iterator pointing to the element after the interval that was erased
// (or end() if none exists).
//
// template <typename K> size_type erase(const K& key):
//
// Erases the element with the matching key, if it exists, returning the
// number of elements erased (0 or 1).
using Base::erase;
// btree_map::insert()
//
// Inserts an element of the specified value into the `btree_map`,
// returning an iterator pointing to the newly inserted element, provided that
// an element with the given key does not already exist. If an insertion
// occurs, any references, pointers, or iterators are invalidated.
// Overloads are listed below.
//
// std::pair<iterator,bool> insert(const value_type& value):
//
// Inserts a value into the `btree_map`. Returns a pair consisting of an
// iterator to the inserted element (or to the element that prevented the
// insertion) and a bool denoting whether the insertion took place.
//
// std::pair<iterator,bool> insert(value_type&& value):
//
// Inserts a moveable value into the `btree_map`. Returns a pair
// consisting of an iterator to the inserted element (or to the element that
// prevented the insertion) and a bool denoting whether the insertion took
// place.
//
// iterator insert(const_iterator hint, const value_type& value):
// iterator insert(const_iterator hint, value_type&& value):
//
// Inserts a value, using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search. Returns an iterator to the
// inserted element, or to the existing element that prevented the
// insertion.
//
// void insert(InputIterator first, InputIterator last):
//
// Inserts a range of values [`first`, `last`).
//
// void insert(std::initializer_list<init_type> ilist):
//
// Inserts the elements within the initializer list `ilist`.
using Base::insert;
// btree_map::insert_or_assign()
//
// Inserts an element of the specified value into the `btree_map` provided
// that a value with the given key does not already exist, or replaces the
// corresponding mapped type with the forwarded `obj` argument if a key for
// that value already exists, returning an iterator pointing to the newly
// inserted element. Overloads are listed below.
//
// pair<iterator, bool> insert_or_assign(const key_type& k, M&& obj):
// pair<iterator, bool> insert_or_assign(key_type&& k, M&& obj):
//
// Inserts/Assigns (or moves) the element of the specified key into the
// `btree_map`. If the returned bool is true, insertion took place, and if
// it's false, assignment took place.
//
// iterator insert_or_assign(const_iterator hint,
// const key_type& k, M&& obj):
// iterator insert_or_assign(const_iterator hint, key_type&& k, M&& obj):
//
// Inserts/Assigns (or moves) the element of the specified key into the
// `btree_map` using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search.
using Base::insert_or_assign;
// btree_map::emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `btree_map`, provided that no element with the given key
// already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately. Prefer `try_emplace()` unless your key is not
// copyable or moveable.
//
// If an insertion occurs, any references, pointers, or iterators are
// invalidated.
using Base::emplace;
// btree_map::emplace_hint()
//
// Inserts an element of the specified value by constructing it in-place
// within the `btree_map`, using the position of `hint` as a non-binding
// suggestion for where to begin the insertion search, and only inserts
// provided that no element with the given key already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately. Prefer `try_emplace()` unless your key is not
// copyable or moveable.
//
// If an insertion occurs, any references, pointers, or iterators are
// invalidated.
using Base::emplace_hint;
// btree_map::try_emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `btree_map`, provided that no element with the given key
// already exists. Unlike `emplace()`, if an element with the given key
// already exists, we guarantee that no element is constructed.
//
// If an insertion occurs, any references, pointers, or iterators are
// invalidated.
//
// Overloads are listed below.
//
// std::pair<iterator, bool> try_emplace(const key_type& k, Args&&... args):
// std::pair<iterator, bool> try_emplace(key_type&& k, Args&&... args):
//
// Inserts (via copy or move) the element of the specified key into the
// `btree_map`.
//
// iterator try_emplace(const_iterator hint,
// const key_type& k, Args&&... args):
// iterator try_emplace(const_iterator hint, key_type&& k, Args&&... args):
//
// Inserts (via copy or move) the element of the specified key into the
// `btree_map` using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search.
using Base::try_emplace;
// btree_map::extract()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle. Any references, pointers, or iterators
// are invalidated. Overloads are listed below.
//
// node_type extract(const_iterator position):
//
// Extracts the element at the indicated position and returns a node handle
// owning that extracted data.
//
// template <typename K> node_type extract(const K& k):
//
// Extracts the element with the key matching the passed key value and
// returns a node handle owning that extracted data. If the `btree_map`
// does not contain an element with a matching key, this function returns an
// empty node handle.
//
// NOTE: when compiled in an earlier version of C++ than C++17,
// `node_type::key()` returns a const reference to the key instead of a
// mutable reference. We cannot safely return a mutable reference without
// std::launder (which is not available before C++17).
//
// NOTE: In this context, `node_type` refers to the C++17 concept of a
// move-only type that owns and provides access to the elements in associative
// containers (https://en.cppreference.com/w/cpp/container/node_handle).
// It does NOT refer to the data layout of the underlying btree.
using Base::extract;
// btree_map::extract_and_get_next()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle along with an iterator to the next
// element.
//
// extract_and_get_next_return_type extract_and_get_next(
// const_iterator position):
//
// Extracts the element at the indicated position, returns a struct
// containing a member named `node`: a node handle owning that extracted
// data and a member named `next`: an iterator pointing to the next element
// in the btree.
using Base::extract_and_get_next;
// btree_map::merge()
//
// Extracts elements from a given `source` btree_map into this
// `btree_map`. If the destination `btree_map` already contains an
// element with an equivalent key, that element is not extracted.
using Base::merge;
// btree_map::swap(btree_map& other)
//
// Exchanges the contents of this `btree_map` with those of the `other`
// btree_map, avoiding invocation of any move, copy, or swap operations on
// individual elements.
//
// All iterators and references on the `btree_map` remain valid, excepting
// for the past-the-end iterator, which is invalidated.
using Base::swap;
// btree_map::at()
//
// Returns a reference to the mapped value of the element with key equivalent
// to the passed key.
using Base::at;
// btree_map::contains()
//
// template <typename K> bool contains(const K& key) const:
//
// Determines whether an element comparing equal to the given `key` exists
// within the `btree_map`, returning `true` if so or `false` otherwise.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::contains;
// btree_map::count()
//
// template <typename K> size_type count(const K& key) const:
//
// Returns the number of elements comparing equal to the given `key` within
// the `btree_map`. Note that this function will return either `1` or `0`
// since duplicate elements are not allowed within a `btree_map`.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::count;
// btree_map::equal_range()
//
// Returns a half-open range [first, last), defined by a `std::pair` of two
// iterators, containing all elements with the passed key in the `btree_map`.
using Base::equal_range;
// btree_map::find()
//
// template <typename K> iterator find(const K& key):
// template <typename K> const_iterator find(const K& key) const:
//
// Finds an element with the passed `key` within the `btree_map`.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::find;
// btree_map::lower_bound()
//
// template <typename K> iterator lower_bound(const K& key):
// template <typename K> const_iterator lower_bound(const K& key) const:
//
// Finds the first element with a key that is not less than `key` within the
// `btree_map`.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::lower_bound;
// btree_map::upper_bound()
//
// template <typename K> iterator upper_bound(const K& key):
// template <typename K> const_iterator upper_bound(const K& key) const:
//
// Finds the first element with a key that is greater than `key` within the
// `btree_map`.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::upper_bound;
// btree_map::operator[]()
//
// Returns a reference to the value mapped to the passed key within the
// `btree_map`, performing an `insert()` if the key does not already
// exist.
//
// If an insertion occurs, any references, pointers, or iterators are
// invalidated. Otherwise iterators are not affected and references are not
// invalidated. Overloads are listed below.
//
// T& operator[](key_type&& key):
// T& operator[](const key_type& key):
//
// Inserts a value_type object constructed in-place if the element with the
// given key does not exist.
using Base::operator[];
// btree_map::get_allocator()
//
// Returns the allocator function associated with this `btree_map`.
using Base::get_allocator;
// btree_map::key_comp();
//
// Returns the key comparator associated with this `btree_map`.
using Base::key_comp;
// btree_map::value_comp();
//
// Returns the value comparator associated with this `btree_map`.
using Base::value_comp;
};
// absl::swap(absl::btree_map<>, absl::btree_map<>)
//
// Swaps the contents of two `absl::btree_map` containers.
template <typename K, typename V, typename C, typename A>
void swap(btree_map<K, V, C, A> &x, btree_map<K, V, C, A> &y) {
return x.swap(y);
}
// absl::erase_if(absl::btree_map<>, Pred)
//
// Erases all elements that satisfy the predicate pred from the container.
// Returns the number of erased elements.
template <typename K, typename V, typename C, typename A, typename Pred>
typename btree_map<K, V, C, A>::size_type erase_if(
btree_map<K, V, C, A> &map, Pred pred) {
return container_internal::btree_access::erase_if(map, std::move(pred));
}
// absl::btree_multimap
//
// An `absl::btree_multimap<K, V>` is an ordered associative container of
// keys and associated values designed to be a more efficient replacement for
// `std::multimap` (in most cases). Unlike `absl::btree_map`, a B-tree multimap
// allows multiple elements with equivalent keys.
//
// Keys are sorted using an (optional) comparison function, which defaults to
// `std::less<K>`.
//
// An `absl::btree_multimap<K, V>` uses a default allocator of
// `std::allocator<std::pair<const K, V>>` to allocate (and deallocate)
// nodes, and construct and destruct values within those nodes. You may
// instead specify a custom allocator `A` (which in turn requires specifying a
// custom comparator `C`) as in `absl::btree_multimap<K, V, C, A>`.
//
template <typename Key, typename Value, typename Compare = std::less<Key>,
typename Alloc = std::allocator<std::pair<const Key, Value>>>
class btree_multimap
: public container_internal::btree_multimap_container<
container_internal::btree<container_internal::map_params<
Key, Value, Compare, Alloc, /*TargetNodeSize=*/256,
/*IsMulti=*/true>>> {
using Base = typename btree_multimap::btree_multimap_container;
public:
// Constructors and Assignment Operators
//
// A `btree_multimap` supports the same overload set as `std::multimap`
// for construction and assignment:
//
// * Default constructor
//
// absl::btree_multimap<int, std::string> map1;
//
// * Initializer List constructor
//
// absl::btree_multimap<int, std::string> map2 =
// {{1, "huey"}, {2, "dewey"}, {3, "louie"},};
//
// * Copy constructor
//
// absl::btree_multimap<int, std::string> map3(map2);
//
// * Copy assignment operator
//
// absl::btree_multimap<int, std::string> map4;
// map4 = map3;
//
// * Move constructor
//
// // Move is guaranteed efficient
// absl::btree_multimap<int, std::string> map5(std::move(map4));
//
// * Move assignment operator
//
// // May be efficient if allocators are compatible
// absl::btree_multimap<int, std::string> map6;
// map6 = std::move(map5);
//
// * Range constructor
//
// std::vector<std::pair<int, std::string>> v = {{1, "a"}, {2, "b"}};
// absl::btree_multimap<int, std::string> map7(v.begin(), v.end());
btree_multimap() {}
using Base::Base;
// btree_multimap::begin()
//
// Returns an iterator to the beginning of the `btree_multimap`.
using Base::begin;
// btree_multimap::cbegin()
//
// Returns a const iterator to the beginning of the `btree_multimap`.
using Base::cbegin;
// btree_multimap::end()
//
// Returns an iterator to the end of the `btree_multimap`.
using Base::end;
// btree_multimap::cend()
//
// Returns a const iterator to the end of the `btree_multimap`.
using Base::cend;
// btree_multimap::empty()
//
// Returns whether or not the `btree_multimap` is empty.
using Base::empty;
// btree_multimap::max_size()
//
// Returns the largest theoretical possible number of elements within a
// `btree_multimap` under current memory constraints. This value can be
// thought of as the largest value of `std::distance(begin(), end())` for a
// `btree_multimap<Key, T>`.
using Base::max_size;
// btree_multimap::size()
//
// Returns the number of elements currently within the `btree_multimap`.
using Base::size;
// btree_multimap::clear()
//
// Removes all elements from the `btree_multimap`. Invalidates any references,
// pointers, or iterators referring to contained elements.
using Base::clear;
// btree_multimap::erase()
//
// Erases elements within the `btree_multimap`. If an erase occurs, any
// references, pointers, or iterators are invalidated.
// Overloads are listed below.
//
// iterator erase(iterator position):
// iterator erase(const_iterator position):
//
// Erases the element at `position` of the `btree_multimap`, returning
// the iterator pointing to the element after the one that was erased
// (or end() if none exists).
//
// iterator erase(const_iterator first, const_iterator last):
//
// Erases the elements in the open interval [`first`, `last`), returning
// the iterator pointing to the element after the interval that was erased
// (or end() if none exists).
//
// template <typename K> size_type erase(const K& key):
//
// Erases the elements matching the key, if any exist, returning the
// number of elements erased.
using Base::erase;
// btree_multimap::insert()
//
// Inserts an element of the specified value into the `btree_multimap`,
// returning an iterator pointing to the newly inserted element.
// Any references, pointers, or iterators are invalidated. Overloads are
// listed below.
//
// iterator insert(const value_type& value):
//
// Inserts a value into the `btree_multimap`, returning an iterator to the
// inserted element.
//
// iterator insert(value_type&& value):
//
// Inserts a moveable value into the `btree_multimap`, returning an iterator
// to the inserted element.
//
// iterator insert(const_iterator hint, const value_type& value):
// iterator insert(const_iterator hint, value_type&& value):
//
// Inserts a value, using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search. Returns an iterator to the
// inserted element.
//
// void insert(InputIterator first, InputIterator last):
//
// Inserts a range of values [`first`, `last`).
//
// void insert(std::initializer_list<init_type> ilist):
//
// Inserts the elements within the initializer list `ilist`.
using Base::insert;
// btree_multimap::emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `btree_multimap`. Any references, pointers, or iterators are
// invalidated.
using Base::emplace;
// btree_multimap::emplace_hint()
//
// Inserts an element of the specified value by constructing it in-place
// within the `btree_multimap`, using the position of `hint` as a non-binding
// suggestion for where to begin the insertion search.
//
// Any references, pointers, or iterators are invalidated.
using Base::emplace_hint;
// btree_multimap::extract()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle. Overloads are listed below.
//
// node_type extract(const_iterator position):
//
// Extracts the element at the indicated position and returns a node handle
// owning that extracted data.
//
// template <typename K> node_type extract(const K& k):
//
// Extracts the element with the key matching the passed key value and
// returns a node handle owning that extracted data. If the `btree_multimap`
// does not contain an element with a matching key, this function returns an
// empty node handle.
//
// NOTE: when compiled in an earlier version of C++ than C++17,
// `node_type::key()` returns a const reference to the key instead of a
// mutable reference. We cannot safely return a mutable reference without
// std::launder (which is not available before C++17).
//
// NOTE: In this context, `node_type` refers to the C++17 concept of a
// move-only type that owns and provides access to the elements in associative
// containers (https://en.cppreference.com/w/cpp/container/node_handle).
// It does NOT refer to the data layout of the underlying btree.
using Base::extract;
// btree_multimap::extract_and_get_next()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle along with an iterator to the next
// element.
//
// extract_and_get_next_return_type extract_and_get_next(
// const_iterator position):
//
// Extracts the element at the indicated position, returns a struct
// containing a member named `node`: a node handle owning that extracted
// data and a member named `next`: an iterator pointing to the next element
// in the btree.
using Base::extract_and_get_next;
// btree_multimap::merge()
//
// Extracts all elements from a given `source` btree_multimap into this
// `btree_multimap`.
using Base::merge;
// btree_multimap::swap(btree_multimap& other)
//
// Exchanges the contents of this `btree_multimap` with those of the `other`
// btree_multimap, avoiding invocation of any move, copy, or swap operations
// on individual elements.
//
// All iterators and references on the `btree_multimap` remain valid,
// excepting for the past-the-end iterator, which is invalidated.
using Base::swap;
// btree_multimap::contains()
//
// template <typename K> bool contains(const K& key) const:
//
// Determines whether an element comparing equal to the given `key` exists
// within the `btree_multimap`, returning `true` if so or `false` otherwise.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::contains;
// btree_multimap::count()
//
// template <typename K> size_type count(const K& key) const:
//
// Returns the number of elements comparing equal to the given `key` within
// the `btree_multimap`.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::count;
// btree_multimap::equal_range()
//
// Returns a half-open range [first, last), defined by a `std::pair` of two
// iterators, containing all elements with the passed key in the
// `btree_multimap`.
using Base::equal_range;
// btree_multimap::find()
//
// template <typename K> iterator find(const K& key):
// template <typename K> const_iterator find(const K& key) const:
//
// Finds an element with the passed `key` within the `btree_multimap`.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::find;
// btree_multimap::lower_bound()
//
// template <typename K> iterator lower_bound(const K& key):
// template <typename K> const_iterator lower_bound(const K& key) const:
//
// Finds the first element with a key that is not less than `key` within the
// `btree_multimap`.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::lower_bound;
// btree_multimap::upper_bound()
//
// template <typename K> iterator upper_bound(const K& key):
// template <typename K> const_iterator upper_bound(const K& key) const:
//
// Finds the first element with a key that is greater than `key` within the
// `btree_multimap`.
//
// Supports heterogeneous lookup, provided that the map has a compatible
// heterogeneous comparator.
using Base::upper_bound;
// btree_multimap::get_allocator()
//
// Returns the allocator function associated with this `btree_multimap`.
using Base::get_allocator;
// btree_multimap::key_comp();
//
// Returns the key comparator associated with this `btree_multimap`.
using Base::key_comp;
// btree_multimap::value_comp();
//
// Returns the value comparator associated with this `btree_multimap`.
using Base::value_comp;
};
// absl::swap(absl::btree_multimap<>, absl::btree_multimap<>)
//
// Swaps the contents of two `absl::btree_multimap` containers.
template <typename K, typename V, typename C, typename A>
void swap(btree_multimap<K, V, C, A> &x, btree_multimap<K, V, C, A> &y) {
return x.swap(y);
}
// absl::erase_if(absl::btree_multimap<>, Pred)
//
// Erases all elements that satisfy the predicate pred from the container.
// Returns the number of erased elements.
template <typename K, typename V, typename C, typename A, typename Pred>
typename btree_multimap<K, V, C, A>::size_type erase_if(
btree_multimap<K, V, C, A> &map, Pred pred) {
return container_internal::btree_access::erase_if(map, std::move(pred));
}
namespace container_internal {
// A parameters structure for holding the type parameters for a btree_map.
// Compare and Alloc should be nothrow copy-constructible.
template <typename Key, typename Data, typename Compare, typename Alloc,
int TargetNodeSize, bool IsMulti>
struct map_params : common_params<Key, Compare, Alloc, TargetNodeSize, IsMulti,
/*IsMap=*/true, map_slot_policy<Key, Data>> {
using super_type = typename map_params::common_params;
using mapped_type = Data;
// This type allows us to move keys when it is safe to do so. It is safe
// for maps in which value_type and mutable_value_type are layout compatible.
using slot_policy = typename super_type::slot_policy;
using slot_type = typename super_type::slot_type;
using value_type = typename super_type::value_type;
using init_type = typename super_type::init_type;
template <typename V>
static auto key(const V &value ABSL_ATTRIBUTE_LIFETIME_BOUND)
-> decltype((value.first)) {
return value.first;
}
static const Key &key(const slot_type *s) { return slot_policy::key(s); }
static const Key &key(slot_type *s) { return slot_policy::key(s); }
// For use in node handle.
static auto mutable_key(slot_type *s)
-> decltype(slot_policy::mutable_key(s)) {
return slot_policy::mutable_key(s);
}
static mapped_type &value(value_type *value) { return value->second; }
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_BTREE_MAP_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: btree_set.h
// -----------------------------------------------------------------------------
//
// This header file defines B-tree sets: sorted associative containers of
// values.
//
// * `absl::btree_set<>`
// * `absl::btree_multiset<>`
//
// These B-tree types are similar to the corresponding types in the STL
// (`std::set` and `std::multiset`) and generally conform to the STL interfaces
// of those types. However, because they are implemented using B-trees, they
// are more efficient in most situations.
//
// Unlike `std::set` and `std::multiset`, which are commonly implemented using
// red-black tree nodes, B-tree sets use more generic B-tree nodes able to hold
// multiple values per node. Holding multiple values per node often makes
// B-tree sets perform better than their `std::set` counterparts, because
// multiple entries can be checked within the same cache hit.
//
// However, these types should not be considered drop-in replacements for
// `std::set` and `std::multiset` as there are some API differences, which are
// noted in this header file. The most consequential differences with respect to
// migrating to b-tree from the STL types are listed in the next paragraph.
// Other API differences are minor.
//
// Importantly, insertions and deletions may invalidate outstanding iterators,
// pointers, and references to elements. Such invalidations are typically only
// an issue if insertion and deletion operations are interleaved with the use of
// more than one iterator, pointer, or reference simultaneously. For this
// reason, `insert()`, `erase()`, and `extract_and_get_next()` return a valid
// iterator at the current position.
//
// Another API difference is that btree iterators can be subtracted, and this
// is faster than using std::distance.
#ifndef ABSL_CONTAINER_BTREE_SET_H_
#define ABSL_CONTAINER_BTREE_SET_H_
#include "absl/container/internal/btree.h" // IWYU pragma: export
#include "absl/container/internal/btree_container.h" // IWYU pragma: export
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <typename Key>
struct set_slot_policy;
template <typename Key, typename Compare, typename Alloc, int TargetNodeSize,
bool IsMulti>
struct set_params;
} // namespace container_internal
// absl::btree_set<>
//
// An `absl::btree_set<K>` is an ordered associative container of unique key
// values designed to be a more efficient replacement for `std::set` (in most
// cases).
//
// Keys are sorted using an (optional) comparison function, which defaults to
// `std::less<K>`.
//
// An `absl::btree_set<K>` uses a default allocator of `std::allocator<K>` to
// allocate (and deallocate) nodes, and construct and destruct values within
// those nodes. You may instead specify a custom allocator `A` (which in turn
// requires specifying a custom comparator `C`) as in
// `absl::btree_set<K, C, A>`.
//
template <typename Key, typename Compare = std::less<Key>,
typename Alloc = std::allocator<Key>>
class btree_set
: public container_internal::btree_set_container<
container_internal::btree<container_internal::set_params<
Key, Compare, Alloc, /*TargetNodeSize=*/256,
/*IsMulti=*/false>>> {
using Base = typename btree_set::btree_set_container;
public:
// Constructors and Assignment Operators
//
// A `btree_set` supports the same overload set as `std::set`
// for construction and assignment:
//
// * Default constructor
//
// absl::btree_set<std::string> set1;
//
// * Initializer List constructor
//
// absl::btree_set<std::string> set2 =
// {{"huey"}, {"dewey"}, {"louie"},};
//
// * Copy constructor
//
// absl::btree_set<std::string> set3(set2);
//
// * Copy assignment operator
//
// absl::btree_set<std::string> set4;
// set4 = set3;
//
// * Move constructor
//
// // Move is guaranteed efficient
// absl::btree_set<std::string> set5(std::move(set4));
//
// * Move assignment operator
//
// // May be efficient if allocators are compatible
// absl::btree_set<std::string> set6;
// set6 = std::move(set5);
//
// * Range constructor
//
// std::vector<std::string> v = {"a", "b"};
// absl::btree_set<std::string> set7(v.begin(), v.end());
btree_set() {}
using Base::Base;
// btree_set::begin()
//
// Returns an iterator to the beginning of the `btree_set`.
using Base::begin;
// btree_set::cbegin()
//
// Returns a const iterator to the beginning of the `btree_set`.
using Base::cbegin;
// btree_set::end()
//
// Returns an iterator to the end of the `btree_set`.
using Base::end;
// btree_set::cend()
//
// Returns a const iterator to the end of the `btree_set`.
using Base::cend;
// btree_set::empty()
//
// Returns whether or not the `btree_set` is empty.
using Base::empty;
// btree_set::max_size()
//
// Returns the largest theoretical possible number of elements within a
// `btree_set` under current memory constraints. This value can be thought
// of as the largest value of `std::distance(begin(), end())` for a
// `btree_set<Key>`.
using Base::max_size;
// btree_set::size()
//
// Returns the number of elements currently within the `btree_set`.
using Base::size;
// btree_set::clear()
//
// Removes all elements from the `btree_set`. Invalidates any references,
// pointers, or iterators referring to contained elements.
using Base::clear;
// btree_set::erase()
//
// Erases elements within the `btree_set`. Overloads are listed below.
//
// iterator erase(iterator position):
// iterator erase(const_iterator position):
//
// Erases the element at `position` of the `btree_set`, returning
// the iterator pointing to the element after the one that was erased
// (or end() if none exists).
//
// iterator erase(const_iterator first, const_iterator last):
//
// Erases the elements in the open interval [`first`, `last`), returning
// the iterator pointing to the element after the interval that was erased
// (or end() if none exists).
//
// template <typename K> size_type erase(const K& key):
//
// Erases the element with the matching key, if it exists, returning the
// number of elements erased (0 or 1).
using Base::erase;
// btree_set::insert()
//
// Inserts an element of the specified value into the `btree_set`,
// returning an iterator pointing to the newly inserted element, provided that
// an element with the given key does not already exist. If an insertion
// occurs, any references, pointers, or iterators are invalidated.
// Overloads are listed below.
//
// std::pair<iterator,bool> insert(const value_type& value):
//
// Inserts a value into the `btree_set`. Returns a pair consisting of an
// iterator to the inserted element (or to the element that prevented the
// insertion) and a bool denoting whether the insertion took place.
//
// std::pair<iterator,bool> insert(value_type&& value):
//
// Inserts a moveable value into the `btree_set`. Returns a pair
// consisting of an iterator to the inserted element (or to the element that
// prevented the insertion) and a bool denoting whether the insertion took
// place.
//
// iterator insert(const_iterator hint, const value_type& value):
// iterator insert(const_iterator hint, value_type&& value):
//
// Inserts a value, using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search. Returns an iterator to the
// inserted element, or to the existing element that prevented the
// insertion.
//
// void insert(InputIterator first, InputIterator last):
//
// Inserts a range of values [`first`, `last`).
//
// void insert(std::initializer_list<init_type> ilist):
//
// Inserts the elements within the initializer list `ilist`.
using Base::insert;
// btree_set::emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `btree_set`, provided that no element with the given key
// already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately.
//
// If an insertion occurs, any references, pointers, or iterators are
// invalidated.
using Base::emplace;
// btree_set::emplace_hint()
//
// Inserts an element of the specified value by constructing it in-place
// within the `btree_set`, using the position of `hint` as a non-binding
// suggestion for where to begin the insertion search, and only inserts
// provided that no element with the given key already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately.
//
// If an insertion occurs, any references, pointers, or iterators are
// invalidated.
using Base::emplace_hint;
// btree_set::extract()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle. Any references, pointers, or iterators
// are invalidated. Overloads are listed below.
//
// node_type extract(const_iterator position):
//
// Extracts the element at the indicated position and returns a node handle
// owning that extracted data.
//
// template <typename K> node_type extract(const K& k):
//
// Extracts the element with the key matching the passed key value and
// returns a node handle owning that extracted data. If the `btree_set`
// does not contain an element with a matching key, this function returns an
// empty node handle.
//
// NOTE: In this context, `node_type` refers to the C++17 concept of a
// move-only type that owns and provides access to the elements in associative
// containers (https://en.cppreference.com/w/cpp/container/node_handle).
// It does NOT refer to the data layout of the underlying btree.
using Base::extract;
// btree_set::extract_and_get_next()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle along with an iterator to the next
// element.
//
// extract_and_get_next_return_type extract_and_get_next(
// const_iterator position):
//
// Extracts the element at the indicated position, returns a struct
// containing a member named `node`: a node handle owning that extracted
// data and a member named `next`: an iterator pointing to the next element
// in the btree.
using Base::extract_and_get_next;
// btree_set::merge()
//
// Extracts elements from a given `source` btree_set into this
// `btree_set`. If the destination `btree_set` already contains an
// element with an equivalent key, that element is not extracted.
using Base::merge;
// btree_set::swap(btree_set& other)
//
// Exchanges the contents of this `btree_set` with those of the `other`
// btree_set, avoiding invocation of any move, copy, or swap operations on
// individual elements.
//
// All iterators and references on the `btree_set` remain valid, excepting
// for the past-the-end iterator, which is invalidated.
using Base::swap;
// btree_set::contains()
//
// template <typename K> bool contains(const K& key) const:
//
// Determines whether an element comparing equal to the given `key` exists
// within the `btree_set`, returning `true` if so or `false` otherwise.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::contains;
// btree_set::count()
//
// template <typename K> size_type count(const K& key) const:
//
// Returns the number of elements comparing equal to the given `key` within
// the `btree_set`. Note that this function will return either `1` or `0`
// since duplicate elements are not allowed within a `btree_set`.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::count;
// btree_set::equal_range()
//
// Returns a closed range [first, last], defined by a `std::pair` of two
// iterators, containing all elements with the passed key in the
// `btree_set`.
using Base::equal_range;
// btree_set::find()
//
// template <typename K> iterator find(const K& key):
// template <typename K> const_iterator find(const K& key) const:
//
// Finds an element with the passed `key` within the `btree_set`.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::find;
// btree_set::lower_bound()
//
// template <typename K> iterator lower_bound(const K& key):
// template <typename K> const_iterator lower_bound(const K& key) const:
//
// Finds the first element that is not less than `key` within the `btree_set`.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::lower_bound;
// btree_set::upper_bound()
//
// template <typename K> iterator upper_bound(const K& key):
// template <typename K> const_iterator upper_bound(const K& key) const:
//
// Finds the first element that is greater than `key` within the `btree_set`.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::upper_bound;
// btree_set::get_allocator()
//
// Returns the allocator function associated with this `btree_set`.
using Base::get_allocator;
// btree_set::key_comp();
//
// Returns the key comparator associated with this `btree_set`.
using Base::key_comp;
// btree_set::value_comp();
//
// Returns the value comparator associated with this `btree_set`. The keys to
// sort the elements are the values themselves, therefore `value_comp` and its
// sibling member function `key_comp` are equivalent.
using Base::value_comp;
};
// absl::swap(absl::btree_set<>, absl::btree_set<>)
//
// Swaps the contents of two `absl::btree_set` containers.
template <typename K, typename C, typename A>
void swap(btree_set<K, C, A> &x, btree_set<K, C, A> &y) {
return x.swap(y);
}
// absl::erase_if(absl::btree_set<>, Pred)
//
// Erases all elements that satisfy the predicate pred from the container.
// Returns the number of erased elements.
template <typename K, typename C, typename A, typename Pred>
typename btree_set<K, C, A>::size_type erase_if(btree_set<K, C, A> &set,
Pred pred) {
return container_internal::btree_access::erase_if(set, std::move(pred));
}
// absl::btree_multiset<>
//
// An `absl::btree_multiset<K>` is an ordered associative container of
// keys and associated values designed to be a more efficient replacement
// for `std::multiset` (in most cases). Unlike `absl::btree_set`, a B-tree
// multiset allows equivalent elements.
//
// Keys are sorted using an (optional) comparison function, which defaults to
// `std::less<K>`.
//
// An `absl::btree_multiset<K>` uses a default allocator of `std::allocator<K>`
// to allocate (and deallocate) nodes, and construct and destruct values within
// those nodes. You may instead specify a custom allocator `A` (which in turn
// requires specifying a custom comparator `C`) as in
// `absl::btree_multiset<K, C, A>`.
//
template <typename Key, typename Compare = std::less<Key>,
typename Alloc = std::allocator<Key>>
class btree_multiset
: public container_internal::btree_multiset_container<
container_internal::btree<container_internal::set_params<
Key, Compare, Alloc, /*TargetNodeSize=*/256,
/*IsMulti=*/true>>> {
using Base = typename btree_multiset::btree_multiset_container;
public:
// Constructors and Assignment Operators
//
// A `btree_multiset` supports the same overload set as `std::set`
// for construction and assignment:
//
// * Default constructor
//
// absl::btree_multiset<std::string> set1;
//
// * Initializer List constructor
//
// absl::btree_multiset<std::string> set2 =
// {{"huey"}, {"dewey"}, {"louie"},};
//
// * Copy constructor
//
// absl::btree_multiset<std::string> set3(set2);
//
// * Copy assignment operator
//
// absl::btree_multiset<std::string> set4;
// set4 = set3;
//
// * Move constructor
//
// // Move is guaranteed efficient
// absl::btree_multiset<std::string> set5(std::move(set4));
//
// * Move assignment operator
//
// // May be efficient if allocators are compatible
// absl::btree_multiset<std::string> set6;
// set6 = std::move(set5);
//
// * Range constructor
//
// std::vector<std::string> v = {"a", "b"};
// absl::btree_multiset<std::string> set7(v.begin(), v.end());
btree_multiset() {}
using Base::Base;
// btree_multiset::begin()
//
// Returns an iterator to the beginning of the `btree_multiset`.
using Base::begin;
// btree_multiset::cbegin()
//
// Returns a const iterator to the beginning of the `btree_multiset`.
using Base::cbegin;
// btree_multiset::end()
//
// Returns an iterator to the end of the `btree_multiset`.
using Base::end;
// btree_multiset::cend()
//
// Returns a const iterator to the end of the `btree_multiset`.
using Base::cend;
// btree_multiset::empty()
//
// Returns whether or not the `btree_multiset` is empty.
using Base::empty;
// btree_multiset::max_size()
//
// Returns the largest theoretical possible number of elements within a
// `btree_multiset` under current memory constraints. This value can be
// thought of as the largest value of `std::distance(begin(), end())` for a
// `btree_multiset<Key>`.
using Base::max_size;
// btree_multiset::size()
//
// Returns the number of elements currently within the `btree_multiset`.
using Base::size;
// btree_multiset::clear()
//
// Removes all elements from the `btree_multiset`. Invalidates any references,
// pointers, or iterators referring to contained elements.
using Base::clear;
// btree_multiset::erase()
//
// Erases elements within the `btree_multiset`. Overloads are listed below.
//
// iterator erase(iterator position):
// iterator erase(const_iterator position):
//
// Erases the element at `position` of the `btree_multiset`, returning
// the iterator pointing to the element after the one that was erased
// (or end() if none exists).
//
// iterator erase(const_iterator first, const_iterator last):
//
// Erases the elements in the open interval [`first`, `last`), returning
// the iterator pointing to the element after the interval that was erased
// (or end() if none exists).
//
// template <typename K> size_type erase(const K& key):
//
// Erases the elements matching the key, if any exist, returning the
// number of elements erased.
using Base::erase;
// btree_multiset::insert()
//
// Inserts an element of the specified value into the `btree_multiset`,
// returning an iterator pointing to the newly inserted element.
// Any references, pointers, or iterators are invalidated. Overloads are
// listed below.
//
// iterator insert(const value_type& value):
//
// Inserts a value into the `btree_multiset`, returning an iterator to the
// inserted element.
//
// iterator insert(value_type&& value):
//
// Inserts a moveable value into the `btree_multiset`, returning an iterator
// to the inserted element.
//
// iterator insert(const_iterator hint, const value_type& value):
// iterator insert(const_iterator hint, value_type&& value):
//
// Inserts a value, using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search. Returns an iterator to the
// inserted element.
//
// void insert(InputIterator first, InputIterator last):
//
// Inserts a range of values [`first`, `last`).
//
// void insert(std::initializer_list<init_type> ilist):
//
// Inserts the elements within the initializer list `ilist`.
using Base::insert;
// btree_multiset::emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `btree_multiset`. Any references, pointers, or iterators are
// invalidated.
using Base::emplace;
// btree_multiset::emplace_hint()
//
// Inserts an element of the specified value by constructing it in-place
// within the `btree_multiset`, using the position of `hint` as a non-binding
// suggestion for where to begin the insertion search.
//
// Any references, pointers, or iterators are invalidated.
using Base::emplace_hint;
// btree_multiset::extract()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle. Overloads are listed below.
//
// node_type extract(const_iterator position):
//
// Extracts the element at the indicated position and returns a node handle
// owning that extracted data.
//
// template <typename K> node_type extract(const K& k):
//
// Extracts the element with the key matching the passed key value and
// returns a node handle owning that extracted data. If the `btree_multiset`
// does not contain an element with a matching key, this function returns an
// empty node handle.
//
// NOTE: In this context, `node_type` refers to the C++17 concept of a
// move-only type that owns and provides access to the elements in associative
// containers (https://en.cppreference.com/w/cpp/container/node_handle).
// It does NOT refer to the data layout of the underlying btree.
using Base::extract;
// btree_multiset::extract_and_get_next()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle along with an iterator to the next
// element.
//
// extract_and_get_next_return_type extract_and_get_next(
// const_iterator position):
//
// Extracts the element at the indicated position, returns a struct
// containing a member named `node`: a node handle owning that extracted
// data and a member named `next`: an iterator pointing to the next element
// in the btree.
using Base::extract_and_get_next;
// btree_multiset::merge()
//
// Extracts all elements from a given `source` btree_multiset into this
// `btree_multiset`.
using Base::merge;
// btree_multiset::swap(btree_multiset& other)
//
// Exchanges the contents of this `btree_multiset` with those of the `other`
// btree_multiset, avoiding invocation of any move, copy, or swap operations
// on individual elements.
//
// All iterators and references on the `btree_multiset` remain valid,
// excepting for the past-the-end iterator, which is invalidated.
using Base::swap;
// btree_multiset::contains()
//
// template <typename K> bool contains(const K& key) const:
//
// Determines whether an element comparing equal to the given `key` exists
// within the `btree_multiset`, returning `true` if so or `false` otherwise.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::contains;
// btree_multiset::count()
//
// template <typename K> size_type count(const K& key) const:
//
// Returns the number of elements comparing equal to the given `key` within
// the `btree_multiset`.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::count;
// btree_multiset::equal_range()
//
// Returns a closed range [first, last], defined by a `std::pair` of two
// iterators, containing all elements with the passed key in the
// `btree_multiset`.
using Base::equal_range;
// btree_multiset::find()
//
// template <typename K> iterator find(const K& key):
// template <typename K> const_iterator find(const K& key) const:
//
// Finds an element with the passed `key` within the `btree_multiset`.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::find;
// btree_multiset::lower_bound()
//
// template <typename K> iterator lower_bound(const K& key):
// template <typename K> const_iterator lower_bound(const K& key) const:
//
// Finds the first element that is not less than `key` within the
// `btree_multiset`.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::lower_bound;
// btree_multiset::upper_bound()
//
// template <typename K> iterator upper_bound(const K& key):
// template <typename K> const_iterator upper_bound(const K& key) const:
//
// Finds the first element that is greater than `key` within the
// `btree_multiset`.
//
// Supports heterogeneous lookup, provided that the set has a compatible
// heterogeneous comparator.
using Base::upper_bound;
// btree_multiset::get_allocator()
//
// Returns the allocator function associated with this `btree_multiset`.
using Base::get_allocator;
// btree_multiset::key_comp();
//
// Returns the key comparator associated with this `btree_multiset`.
using Base::key_comp;
// btree_multiset::value_comp();
//
// Returns the value comparator associated with this `btree_multiset`. The
// keys to sort the elements are the values themselves, therefore `value_comp`
// and its sibling member function `key_comp` are equivalent.
using Base::value_comp;
};
// absl::swap(absl::btree_multiset<>, absl::btree_multiset<>)
//
// Swaps the contents of two `absl::btree_multiset` containers.
template <typename K, typename C, typename A>
void swap(btree_multiset<K, C, A> &x, btree_multiset<K, C, A> &y) {
return x.swap(y);
}
// absl::erase_if(absl::btree_multiset<>, Pred)
//
// Erases all elements that satisfy the predicate pred from the container.
// Returns the number of erased elements.
template <typename K, typename C, typename A, typename Pred>
typename btree_multiset<K, C, A>::size_type erase_if(
btree_multiset<K, C, A> & set, Pred pred) {
return container_internal::btree_access::erase_if(set, std::move(pred));
}
namespace container_internal {
// This type implements the necessary functions from the
// absl::container_internal::slot_type interface for btree_(multi)set.
template <typename Key>
struct set_slot_policy {
using slot_type = Key;
using value_type = Key;
using mutable_value_type = Key;
static value_type &element(slot_type *slot) { return *slot; }
static const value_type &element(const slot_type *slot) { return *slot; }
template <typename Alloc, class... Args>
static void construct(Alloc *alloc, slot_type *slot, Args &&...args) {
absl::allocator_traits<Alloc>::construct(*alloc, slot,
std::forward<Args>(args)...);
}
template <typename Alloc>
static void construct(Alloc *alloc, slot_type *slot, slot_type *other) {
absl::allocator_traits<Alloc>::construct(*alloc, slot, std::move(*other));
}
template <typename Alloc>
static void construct(Alloc *alloc, slot_type *slot, const slot_type *other) {
absl::allocator_traits<Alloc>::construct(*alloc, slot, *other);
}
template <typename Alloc>
static void destroy(Alloc *alloc, slot_type *slot) {
absl::allocator_traits<Alloc>::destroy(*alloc, slot);
}
};
// A parameters structure for holding the type parameters for a btree_set.
// Compare and Alloc should be nothrow copy-constructible.
template <typename Key, typename Compare, typename Alloc, int TargetNodeSize,
bool IsMulti>
struct set_params : common_params<Key, Compare, Alloc, TargetNodeSize, IsMulti,
/*IsMap=*/false, set_slot_policy<Key>> {
using value_type = Key;
using slot_type = typename set_params::common_params::slot_type;
template <typename V>
static const V &key(const V &value) {
return value;
}
static const Key &key(const slot_type *slot) { return *slot; }
static const Key &key(slot_type *slot) { return *slot; }
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_BTREE_SET_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_BTREE_TEST_H_
#define ABSL_CONTAINER_BTREE_TEST_H_
#include <algorithm>
#include <cassert>
#include <random>
#include <string>
#include <utility>
#include <vector>
#include "absl/container/btree_map.h"
#include "absl/container/btree_set.h"
#include "absl/container/flat_hash_set.h"
#include "absl/strings/cord.h"
#include "absl/time/time.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// Like remove_const but propagates the removal through std::pair.
template <typename T>
struct remove_pair_const {
using type = typename std::remove_const<T>::type;
};
template <typename T, typename U>
struct remove_pair_const<std::pair<T, U> > {
using type = std::pair<typename remove_pair_const<T>::type,
typename remove_pair_const<U>::type>;
};
// Utility class to provide an accessor for a key given a value. The default
// behavior is to treat the value as a pair and return the first element.
template <typename K, typename V>
struct KeyOfValue {
struct type {
const K& operator()(const V& p) const { return p.first; }
};
};
// Partial specialization of KeyOfValue class for when the key and value are
// the same type such as in set<> and btree_set<>.
template <typename K>
struct KeyOfValue<K, K> {
struct type {
const K& operator()(const K& k) const { return k; }
};
};
inline char* GenerateDigits(char buf[16], unsigned val, unsigned maxval) {
assert(val <= maxval);
constexpr unsigned kBase = 64; // avoid integer division.
unsigned p = 15;
buf[p--] = 0;
while (maxval > 0) {
buf[p--] = ' ' + (val % kBase);
val /= kBase;
maxval /= kBase;
}
return buf + p + 1;
}
template <typename K>
struct Generator {
int maxval;
explicit Generator(int m) : maxval(m) {}
K operator()(int i) const {
assert(i <= maxval);
return K(i);
}
};
template <>
struct Generator<absl::Time> {
int maxval;
explicit Generator(int m) : maxval(m) {}
absl::Time operator()(int i) const { return absl::FromUnixMillis(i); }
};
template <>
struct Generator<std::string> {
int maxval;
explicit Generator(int m) : maxval(m) {}
std::string operator()(int i) const {
char buf[16];
return GenerateDigits(buf, i, maxval);
}
};
template <>
struct Generator<Cord> {
int maxval;
explicit Generator(int m) : maxval(m) {}
Cord operator()(int i) const {
char buf[16];
return Cord(GenerateDigits(buf, i, maxval));
}
};
template <typename T, typename U>
struct Generator<std::pair<T, U> > {
Generator<typename remove_pair_const<T>::type> tgen;
Generator<typename remove_pair_const<U>::type> ugen;
explicit Generator(int m) : tgen(m), ugen(m) {}
std::pair<T, U> operator()(int i) const {
return std::make_pair(tgen(i), ugen(i));
}
};
// Generate n values for our tests and benchmarks. Value range is [0, maxval].
inline std::vector<int> GenerateNumbersWithSeed(int n, int maxval, int seed) {
// NOTE: Some tests rely on generated numbers not changing between test runs.
// We use std::minstd_rand0 because it is well-defined, but don't use
// std::uniform_int_distribution because platforms use different algorithms.
std::minstd_rand0 rng(seed);
std::vector<int> values;
absl::flat_hash_set<int> unique_values;
if (values.size() < n) {
for (int i = values.size(); i < n; i++) {
int value;
do {
value = static_cast<int>(rng()) % (maxval + 1);
} while (!unique_values.insert(value).second);
values.push_back(value);
}
}
return values;
}
// Generates n values in the range [0, maxval].
template <typename V>
std::vector<V> GenerateValuesWithSeed(int n, int maxval, int seed) {
const std::vector<int> nums = GenerateNumbersWithSeed(n, maxval, seed);
Generator<V> gen(maxval);
std::vector<V> vec;
vec.reserve(n);
for (int i = 0; i < n; i++) {
vec.push_back(gen(nums[i]));
}
return vec;
}
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_BTREE_TEST_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: fixed_array.h
// -----------------------------------------------------------------------------
//
// A `FixedArray<T>` represents a non-resizable array of `T` where the length of
// the array can be determined at run-time. It is a good replacement for
// non-standard and deprecated uses of `alloca()` and variable length arrays
// within the GCC extension. (See
// https://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html).
//
// `FixedArray` allocates small arrays inline, keeping performance fast by
// avoiding heap operations. It also helps reduce the chances of
// accidentally overflowing your stack if large input is passed to
// your function.
#ifndef ABSL_CONTAINER_FIXED_ARRAY_H_
#define ABSL_CONTAINER_FIXED_ARRAY_H_
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <initializer_list>
#include <iterator>
#include <limits>
#include <memory>
#include <new>
#include <type_traits>
#include "absl/algorithm/algorithm.h"
#include "absl/base/config.h"
#include "absl/base/dynamic_annotations.h"
#include "absl/base/internal/throw_delegate.h"
#include "absl/base/macros.h"
#include "absl/base/optimization.h"
#include "absl/base/port.h"
#include "absl/container/internal/compressed_tuple.h"
#include "absl/memory/memory.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
constexpr static auto kFixedArrayUseDefault = static_cast<size_t>(-1);
// -----------------------------------------------------------------------------
// FixedArray
// -----------------------------------------------------------------------------
//
// A `FixedArray` provides a run-time fixed-size array, allocating a small array
// inline for efficiency.
//
// Most users should not specify the `N` template parameter and let `FixedArray`
// automatically determine the number of elements to store inline based on
// `sizeof(T)`. If `N` is specified, the `FixedArray` implementation will use
// inline storage for arrays with a length <= `N`.
//
// Note that a `FixedArray` constructed with a `size_type` argument will
// default-initialize its values by leaving trivially constructible types
// uninitialized (e.g. int, int[4], double), and others default-constructed.
// This matches the behavior of c-style arrays and `std::array`, but not
// `std::vector`.
template <typename T, size_t N = kFixedArrayUseDefault,
typename A = std::allocator<T>>
class FixedArray {
static_assert(!std::is_array<T>::value || std::extent<T>::value > 0,
"Arrays with unknown bounds cannot be used with FixedArray.");
static constexpr size_t kInlineBytesDefault = 256;
using AllocatorTraits = std::allocator_traits<A>;
// std::iterator_traits isn't guaranteed to be SFINAE-friendly until C++17,
// but this seems to be mostly pedantic.
template <typename Iterator>
using EnableIfForwardIterator = absl::enable_if_t<std::is_convertible<
typename std::iterator_traits<Iterator>::iterator_category,
std::forward_iterator_tag>::value>;
static constexpr bool NoexceptCopyable() {
return std::is_nothrow_copy_constructible<StorageElement>::value &&
absl::allocator_is_nothrow<allocator_type>::value;
}
static constexpr bool NoexceptMovable() {
return std::is_nothrow_move_constructible<StorageElement>::value &&
absl::allocator_is_nothrow<allocator_type>::value;
}
static constexpr bool DefaultConstructorIsNonTrivial() {
return !absl::is_trivially_default_constructible<StorageElement>::value;
}
public:
using allocator_type = typename AllocatorTraits::allocator_type;
using value_type = typename AllocatorTraits::value_type;
using pointer = typename AllocatorTraits::pointer;
using const_pointer = typename AllocatorTraits::const_pointer;
using reference = value_type&;
using const_reference = const value_type&;
using size_type = typename AllocatorTraits::size_type;
using difference_type = typename AllocatorTraits::difference_type;
using iterator = pointer;
using const_iterator = const_pointer;
using reverse_iterator = std::reverse_iterator<iterator>;
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
static constexpr size_type inline_elements =
(N == kFixedArrayUseDefault ? kInlineBytesDefault / sizeof(value_type)
: static_cast<size_type>(N));
FixedArray(const FixedArray& other) noexcept(NoexceptCopyable())
: FixedArray(other,
AllocatorTraits::select_on_container_copy_construction(
other.storage_.alloc())) {}
FixedArray(const FixedArray& other,
const allocator_type& a) noexcept(NoexceptCopyable())
: FixedArray(other.begin(), other.end(), a) {}
FixedArray(FixedArray&& other) noexcept(NoexceptMovable())
: FixedArray(std::move(other), other.storage_.alloc()) {}
FixedArray(FixedArray&& other,
const allocator_type& a) noexcept(NoexceptMovable())
: FixedArray(std::make_move_iterator(other.begin()),
std::make_move_iterator(other.end()), a) {}
// Creates an array object that can store `n` elements.
// Note that trivially constructible elements will be uninitialized.
explicit FixedArray(size_type n, const allocator_type& a = allocator_type())
: storage_(n, a) {
if (DefaultConstructorIsNonTrivial()) {
memory_internal::ConstructRange(storage_.alloc(), storage_.begin(),
storage_.end());
}
}
// Creates an array initialized with `n` copies of `val`.
FixedArray(size_type n, const value_type& val,
const allocator_type& a = allocator_type())
: storage_(n, a) {
memory_internal::ConstructRange(storage_.alloc(), storage_.begin(),
storage_.end(), val);
}
// Creates an array initialized with the size and contents of `init_list`.
FixedArray(std::initializer_list<value_type> init_list,
const allocator_type& a = allocator_type())
: FixedArray(init_list.begin(), init_list.end(), a) {}
// Creates an array initialized with the elements from the input
// range. The array's size will always be `std::distance(first, last)`.
// REQUIRES: Iterator must be a forward_iterator or better.
template <typename Iterator, EnableIfForwardIterator<Iterator>* = nullptr>
FixedArray(Iterator first, Iterator last,
const allocator_type& a = allocator_type())
: storage_(std::distance(first, last), a) {
memory_internal::CopyRange(storage_.alloc(), storage_.begin(), first, last);
}
~FixedArray() noexcept {
for (auto* cur = storage_.begin(); cur != storage_.end(); ++cur) {
AllocatorTraits::destroy(storage_.alloc(), cur);
}
}
// Assignments are deleted because they break the invariant that the size of a
// `FixedArray` never changes.
void operator=(FixedArray&&) = delete;
void operator=(const FixedArray&) = delete;
// FixedArray::size()
//
// Returns the length of the fixed array.
size_type size() const { return storage_.size(); }
// FixedArray::max_size()
//
// Returns the largest possible value of `std::distance(begin(), end())` for a
// `FixedArray<T>`. This is equivalent to the most possible addressable bytes
// over the number of bytes taken by T.
constexpr size_type max_size() const {
return (std::numeric_limits<difference_type>::max)() / sizeof(value_type);
}
// FixedArray::empty()
//
// Returns whether or not the fixed array is empty.
bool empty() const { return size() == 0; }
// FixedArray::memsize()
//
// Returns the memory size of the fixed array in bytes.
size_t memsize() const { return size() * sizeof(value_type); }
// FixedArray::data()
//
// Returns a const T* pointer to elements of the `FixedArray`. This pointer
// can be used to access (but not modify) the contained elements.
const_pointer data() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return AsValueType(storage_.begin());
}
// Overload of FixedArray::data() to return a T* pointer to elements of the
// fixed array. This pointer can be used to access and modify the contained
// elements.
pointer data() ABSL_ATTRIBUTE_LIFETIME_BOUND {
return AsValueType(storage_.begin());
}
// FixedArray::operator[]
//
// Returns a reference the ith element of the fixed array.
// REQUIRES: 0 <= i < size()
reference operator[](size_type i) ABSL_ATTRIBUTE_LIFETIME_BOUND {
ABSL_HARDENING_ASSERT(i < size());
return data()[i];
}
// Overload of FixedArray::operator()[] to return a const reference to the
// ith element of the fixed array.
// REQUIRES: 0 <= i < size()
const_reference operator[](size_type i) const ABSL_ATTRIBUTE_LIFETIME_BOUND {
ABSL_HARDENING_ASSERT(i < size());
return data()[i];
}
// FixedArray::at
//
// Bounds-checked access. Returns a reference to the ith element of the fixed
// array, or throws std::out_of_range
reference at(size_type i) ABSL_ATTRIBUTE_LIFETIME_BOUND {
if (ABSL_PREDICT_FALSE(i >= size())) {
base_internal::ThrowStdOutOfRange("FixedArray::at failed bounds check");
}
return data()[i];
}
// Overload of FixedArray::at() to return a const reference to the ith element
// of the fixed array.
const_reference at(size_type i) const ABSL_ATTRIBUTE_LIFETIME_BOUND {
if (ABSL_PREDICT_FALSE(i >= size())) {
base_internal::ThrowStdOutOfRange("FixedArray::at failed bounds check");
}
return data()[i];
}
// FixedArray::front()
//
// Returns a reference to the first element of the fixed array.
reference front() ABSL_ATTRIBUTE_LIFETIME_BOUND {
ABSL_HARDENING_ASSERT(!empty());
return data()[0];
}
// Overload of FixedArray::front() to return a reference to the first element
// of a fixed array of const values.
const_reference front() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
ABSL_HARDENING_ASSERT(!empty());
return data()[0];
}
// FixedArray::back()
//
// Returns a reference to the last element of the fixed array.
reference back() ABSL_ATTRIBUTE_LIFETIME_BOUND {
ABSL_HARDENING_ASSERT(!empty());
return data()[size() - 1];
}
// Overload of FixedArray::back() to return a reference to the last element
// of a fixed array of const values.
const_reference back() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
ABSL_HARDENING_ASSERT(!empty());
return data()[size() - 1];
}
// FixedArray::begin()
//
// Returns an iterator to the beginning of the fixed array.
iterator begin() ABSL_ATTRIBUTE_LIFETIME_BOUND { return data(); }
// Overload of FixedArray::begin() to return a const iterator to the
// beginning of the fixed array.
const_iterator begin() const ABSL_ATTRIBUTE_LIFETIME_BOUND { return data(); }
// FixedArray::cbegin()
//
// Returns a const iterator to the beginning of the fixed array.
const_iterator cbegin() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return begin();
}
// FixedArray::end()
//
// Returns an iterator to the end of the fixed array.
iterator end() ABSL_ATTRIBUTE_LIFETIME_BOUND { return data() + size(); }
// Overload of FixedArray::end() to return a const iterator to the end of the
// fixed array.
const_iterator end() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return data() + size();
}
// FixedArray::cend()
//
// Returns a const iterator to the end of the fixed array.
const_iterator cend() const ABSL_ATTRIBUTE_LIFETIME_BOUND { return end(); }
// FixedArray::rbegin()
//
// Returns a reverse iterator from the end of the fixed array.
reverse_iterator rbegin() ABSL_ATTRIBUTE_LIFETIME_BOUND {
return reverse_iterator(end());
}
// Overload of FixedArray::rbegin() to return a const reverse iterator from
// the end of the fixed array.
const_reverse_iterator rbegin() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return const_reverse_iterator(end());
}
// FixedArray::crbegin()
//
// Returns a const reverse iterator from the end of the fixed array.
const_reverse_iterator crbegin() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return rbegin();
}
// FixedArray::rend()
//
// Returns a reverse iterator from the beginning of the fixed array.
reverse_iterator rend() ABSL_ATTRIBUTE_LIFETIME_BOUND {
return reverse_iterator(begin());
}
// Overload of FixedArray::rend() for returning a const reverse iterator
// from the beginning of the fixed array.
const_reverse_iterator rend() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return const_reverse_iterator(begin());
}
// FixedArray::crend()
//
// Returns a reverse iterator from the beginning of the fixed array.
const_reverse_iterator crend() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return rend();
}
// FixedArray::fill()
//
// Assigns the given `value` to all elements in the fixed array.
void fill(const value_type& val) { std::fill(begin(), end(), val); }
// Relational operators. Equality operators are elementwise using
// `operator==`, while order operators order FixedArrays lexicographically.
friend bool operator==(const FixedArray& lhs, const FixedArray& rhs) {
return std::equal(lhs.begin(), lhs.end(), rhs.begin(), rhs.end());
}
friend bool operator!=(const FixedArray& lhs, const FixedArray& rhs) {
return !(lhs == rhs);
}
friend bool operator<(const FixedArray& lhs, const FixedArray& rhs) {
return std::lexicographical_compare(lhs.begin(), lhs.end(), rhs.begin(),
rhs.end());
}
friend bool operator>(const FixedArray& lhs, const FixedArray& rhs) {
return rhs < lhs;
}
friend bool operator<=(const FixedArray& lhs, const FixedArray& rhs) {
return !(rhs < lhs);
}
friend bool operator>=(const FixedArray& lhs, const FixedArray& rhs) {
return !(lhs < rhs);
}
template <typename H>
friend H AbslHashValue(H h, const FixedArray& v) {
return H::combine(H::combine_contiguous(std::move(h), v.data(), v.size()),
v.size());
}
private:
// StorageElement
//
// For FixedArrays with a C-style-array value_type, StorageElement is a POD
// wrapper struct called StorageElementWrapper that holds the value_type
// instance inside. This is needed for construction and destruction of the
// entire array regardless of how many dimensions it has. For all other cases,
// StorageElement is just an alias of value_type.
//
// Maintainer's Note: The simpler solution would be to simply wrap value_type
// in a struct whether it's an array or not. That causes some paranoid
// diagnostics to misfire, believing that 'data()' returns a pointer to a
// single element, rather than the packed array that it really is.
// e.g.:
//
// FixedArray<char> buf(1);
// sprintf(buf.data(), "foo");
//
// error: call to int __builtin___sprintf_chk(etc...)
// will always overflow destination buffer [-Werror]
//
template <typename OuterT, typename InnerT = absl::remove_extent_t<OuterT>,
size_t InnerN = std::extent<OuterT>::value>
struct StorageElementWrapper {
InnerT array[InnerN];
};
using StorageElement =
absl::conditional_t<std::is_array<value_type>::value,
StorageElementWrapper<value_type>, value_type>;
static pointer AsValueType(pointer ptr) { return ptr; }
static pointer AsValueType(StorageElementWrapper<value_type>* ptr) {
return std::addressof(ptr->array);
}
static_assert(sizeof(StorageElement) == sizeof(value_type), "");
static_assert(alignof(StorageElement) == alignof(value_type), "");
class NonEmptyInlinedStorage {
public:
StorageElement* data() { return reinterpret_cast<StorageElement*>(buff_); }
void AnnotateConstruct(size_type n);
void AnnotateDestruct(size_type n);
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
void* RedzoneBegin() { return &redzone_begin_; }
void* RedzoneEnd() { return &redzone_end_ + 1; }
#endif // ABSL_HAVE_ADDRESS_SANITIZER
private:
ABSL_ADDRESS_SANITIZER_REDZONE(redzone_begin_);
alignas(StorageElement) char buff_[sizeof(StorageElement[inline_elements])];
ABSL_ADDRESS_SANITIZER_REDZONE(redzone_end_);
};
class EmptyInlinedStorage {
public:
StorageElement* data() { return nullptr; }
void AnnotateConstruct(size_type) {}
void AnnotateDestruct(size_type) {}
};
using InlinedStorage =
absl::conditional_t<inline_elements == 0, EmptyInlinedStorage,
NonEmptyInlinedStorage>;
// Storage
//
// An instance of Storage manages the inline and out-of-line memory for
// instances of FixedArray. This guarantees that even when construction of
// individual elements fails in the FixedArray constructor body, the
// destructor for Storage will still be called and out-of-line memory will be
// properly deallocated.
//
class Storage : public InlinedStorage {
public:
Storage(size_type n, const allocator_type& a)
: size_alloc_(n, a), data_(InitializeData()) {}
~Storage() noexcept {
if (UsingInlinedStorage(size())) {
InlinedStorage::AnnotateDestruct(size());
} else {
AllocatorTraits::deallocate(alloc(), AsValueType(begin()), size());
}
}
size_type size() const { return size_alloc_.template get<0>(); }
StorageElement* begin() const { return data_; }
StorageElement* end() const { return begin() + size(); }
allocator_type& alloc() { return size_alloc_.template get<1>(); }
const allocator_type& alloc() const {
return size_alloc_.template get<1>();
}
private:
static bool UsingInlinedStorage(size_type n) {
return n <= inline_elements;
}
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
ABSL_ATTRIBUTE_NOINLINE
#endif // ABSL_HAVE_ADDRESS_SANITIZER
StorageElement* InitializeData() {
if (UsingInlinedStorage(size())) {
InlinedStorage::AnnotateConstruct(size());
return InlinedStorage::data();
} else {
return reinterpret_cast<StorageElement*>(
AllocatorTraits::allocate(alloc(), size()));
}
}
// `CompressedTuple` takes advantage of EBCO for stateless `allocator_type`s
container_internal::CompressedTuple<size_type, allocator_type> size_alloc_;
StorageElement* data_;
};
Storage storage_;
};
#ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL
template <typename T, size_t N, typename A>
constexpr size_t FixedArray<T, N, A>::kInlineBytesDefault;
template <typename T, size_t N, typename A>
constexpr typename FixedArray<T, N, A>::size_type
FixedArray<T, N, A>::inline_elements;
#endif
template <typename T, size_t N, typename A>
void FixedArray<T, N, A>::NonEmptyInlinedStorage::AnnotateConstruct(
typename FixedArray<T, N, A>::size_type n) {
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
if (!n) return;
ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(data(), RedzoneEnd(), RedzoneEnd(),
data() + n);
ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(RedzoneBegin(), data(), data(),
RedzoneBegin());
#endif // ABSL_HAVE_ADDRESS_SANITIZER
static_cast<void>(n); // Mark used when not in asan mode
}
template <typename T, size_t N, typename A>
void FixedArray<T, N, A>::NonEmptyInlinedStorage::AnnotateDestruct(
typename FixedArray<T, N, A>::size_type n) {
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
if (!n) return;
ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(data(), RedzoneEnd(), data() + n,
RedzoneEnd());
ABSL_ANNOTATE_CONTIGUOUS_CONTAINER(RedzoneBegin(), data(), RedzoneBegin(),
data());
#endif // ABSL_HAVE_ADDRESS_SANITIZER
static_cast<void>(n); // Mark used when not in asan mode
}
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_FIXED_ARRAY_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: flat_hash_map.h
// -----------------------------------------------------------------------------
//
// An `absl::flat_hash_map<K, V>` is an unordered associative container of
// unique keys and associated values designed to be a more efficient replacement
// for `std::unordered_map`. Like `unordered_map`, search, insertion, and
// deletion of map elements can be done as an `O(1)` operation. However,
// `flat_hash_map` (and other unordered associative containers known as the
// collection of Abseil "Swiss tables") contain other optimizations that result
// in both memory and computation advantages.
//
// In most cases, your default choice for a hash map should be a map of type
// `flat_hash_map`.
#ifndef ABSL_CONTAINER_FLAT_HASH_MAP_H_
#define ABSL_CONTAINER_FLAT_HASH_MAP_H_
#include <cstddef>
#include <new>
#include <type_traits>
#include <utility>
#include "absl/algorithm/container.h"
#include "absl/base/macros.h"
#include "absl/container/internal/container_memory.h"
#include "absl/container/internal/hash_function_defaults.h" // IWYU pragma: export
#include "absl/container/internal/raw_hash_map.h" // IWYU pragma: export
#include "absl/memory/memory.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class K, class V>
struct FlatHashMapPolicy;
} // namespace container_internal
// -----------------------------------------------------------------------------
// absl::flat_hash_map
// -----------------------------------------------------------------------------
//
// An `absl::flat_hash_map<K, V>` is an unordered associative container which
// has been optimized for both speed and memory footprint in most common use
// cases. Its interface is similar to that of `std::unordered_map<K, V>` with
// the following notable differences:
//
// * Requires keys that are CopyConstructible
// * Requires values that are MoveConstructible
// * Supports heterogeneous lookup, through `find()`, `operator[]()` and
// `insert()`, provided that the map is provided a compatible heterogeneous
// hashing function and equality operator.
// * Invalidates any references and pointers to elements within the table after
// `rehash()` and when the table is moved.
// * Contains a `capacity()` member function indicating the number of element
// slots (open, deleted, and empty) within the hash map.
// * Returns `void` from the `erase(iterator)` overload.
//
// By default, `flat_hash_map` uses the `absl::Hash` hashing framework.
// All fundamental and Abseil types that support the `absl::Hash` framework have
// a compatible equality operator for comparing insertions into `flat_hash_map`.
// If your type is not yet supported by the `absl::Hash` framework, see
// absl/hash/hash.h for information on extending Abseil hashing to user-defined
// types.
//
// Using `absl::flat_hash_map` at interface boundaries in dynamically loaded
// libraries (e.g. .dll, .so) is unsupported due to way `absl::Hash` values may
// be randomized across dynamically loaded libraries.
//
// NOTE: A `flat_hash_map` stores its value types directly inside its
// implementation array to avoid memory indirection. Because a `flat_hash_map`
// is designed to move data when rehashed, map values will not retain pointer
// stability. If you require pointer stability, or if your values are large,
// consider using `absl::flat_hash_map<Key, std::unique_ptr<Value>>` instead.
// If your types are not moveable or you require pointer stability for keys,
// consider `absl::node_hash_map`.
//
// Example:
//
// // Create a flat hash map of three strings (that map to strings)
// absl::flat_hash_map<std::string, std::string> ducks =
// {{"a", "huey"}, {"b", "dewey"}, {"c", "louie"}};
//
// // Insert a new element into the flat hash map
// ducks.insert({"d", "donald"});
//
// // Force a rehash of the flat hash map
// ducks.rehash(0);
//
// // Find the element with the key "b"
// std::string search_key = "b";
// auto result = ducks.find(search_key);
// if (result != ducks.end()) {
// std::cout << "Result: " << result->second << std::endl;
// }
template <class K, class V,
class Hash = absl::container_internal::hash_default_hash<K>,
class Eq = absl::container_internal::hash_default_eq<K>,
class Allocator = std::allocator<std::pair<const K, V>>>
class flat_hash_map : public absl::container_internal::raw_hash_map<
absl::container_internal::FlatHashMapPolicy<K, V>,
Hash, Eq, Allocator> {
using Base = typename flat_hash_map::raw_hash_map;
public:
// Constructors and Assignment Operators
//
// A flat_hash_map supports the same overload set as `std::unordered_map`
// for construction and assignment:
//
// * Default constructor
//
// // No allocation for the table's elements is made.
// absl::flat_hash_map<int, std::string> map1;
//
// * Initializer List constructor
//
// absl::flat_hash_map<int, std::string> map2 =
// {{1, "huey"}, {2, "dewey"}, {3, "louie"},};
//
// * Copy constructor
//
// absl::flat_hash_map<int, std::string> map3(map2);
//
// * Copy assignment operator
//
// // Hash functor and Comparator are copied as well
// absl::flat_hash_map<int, std::string> map4;
// map4 = map3;
//
// * Move constructor
//
// // Move is guaranteed efficient
// absl::flat_hash_map<int, std::string> map5(std::move(map4));
//
// * Move assignment operator
//
// // May be efficient if allocators are compatible
// absl::flat_hash_map<int, std::string> map6;
// map6 = std::move(map5);
//
// * Range constructor
//
// std::vector<std::pair<int, std::string>> v = {{1, "a"}, {2, "b"}};
// absl::flat_hash_map<int, std::string> map7(v.begin(), v.end());
flat_hash_map() {}
using Base::Base;
// flat_hash_map::begin()
//
// Returns an iterator to the beginning of the `flat_hash_map`.
using Base::begin;
// flat_hash_map::cbegin()
//
// Returns a const iterator to the beginning of the `flat_hash_map`.
using Base::cbegin;
// flat_hash_map::cend()
//
// Returns a const iterator to the end of the `flat_hash_map`.
using Base::cend;
// flat_hash_map::end()
//
// Returns an iterator to the end of the `flat_hash_map`.
using Base::end;
// flat_hash_map::capacity()
//
// Returns the number of element slots (assigned, deleted, and empty)
// available within the `flat_hash_map`.
//
// NOTE: this member function is particular to `absl::flat_hash_map` and is
// not provided in the `std::unordered_map` API.
using Base::capacity;
// flat_hash_map::empty()
//
// Returns whether or not the `flat_hash_map` is empty.
using Base::empty;
// flat_hash_map::max_size()
//
// Returns the largest theoretical possible number of elements within a
// `flat_hash_map` under current memory constraints. This value can be thought
// of the largest value of `std::distance(begin(), end())` for a
// `flat_hash_map<K, V>`.
using Base::max_size;
// flat_hash_map::size()
//
// Returns the number of elements currently within the `flat_hash_map`.
using Base::size;
// flat_hash_map::clear()
//
// Removes all elements from the `flat_hash_map`. Invalidates any references,
// pointers, or iterators referring to contained elements.
//
// NOTE: this operation may shrink the underlying buffer. To avoid shrinking
// the underlying buffer call `erase(begin(), end())`.
using Base::clear;
// flat_hash_map::erase()
//
// Erases elements within the `flat_hash_map`. Erasing does not trigger a
// rehash. Overloads are listed below.
//
// void erase(const_iterator pos):
//
// Erases the element at `position` of the `flat_hash_map`, returning
// `void`.
//
// NOTE: returning `void` in this case is different than that of STL
// containers in general and `std::unordered_map` in particular (which
// return an iterator to the element following the erased element). If that
// iterator is needed, simply post increment the iterator:
//
// map.erase(it++);
//
// iterator erase(const_iterator first, const_iterator last):
//
// Erases the elements in the open interval [`first`, `last`), returning an
// iterator pointing to `last`. The special case of calling
// `erase(begin(), end())` resets the reserved growth such that if
// `reserve(N)` has previously been called and there has been no intervening
// call to `clear()`, then after calling `erase(begin(), end())`, it is safe
// to assume that inserting N elements will not cause a rehash.
//
// size_type erase(const key_type& key):
//
// Erases the element with the matching key, if it exists, returning the
// number of elements erased (0 or 1).
using Base::erase;
// flat_hash_map::insert()
//
// Inserts an element of the specified value into the `flat_hash_map`,
// returning an iterator pointing to the newly inserted element, provided that
// an element with the given key does not already exist. If rehashing occurs
// due to the insertion, all iterators are invalidated. Overloads are listed
// below.
//
// std::pair<iterator,bool> insert(const init_type& value):
//
// Inserts a value into the `flat_hash_map`. Returns a pair consisting of an
// iterator to the inserted element (or to the element that prevented the
// insertion) and a bool denoting whether the insertion took place.
//
// std::pair<iterator,bool> insert(T&& value):
// std::pair<iterator,bool> insert(init_type&& value):
//
// Inserts a moveable value into the `flat_hash_map`. Returns a pair
// consisting of an iterator to the inserted element (or to the element that
// prevented the insertion) and a bool denoting whether the insertion took
// place.
//
// iterator insert(const_iterator hint, const init_type& value):
// iterator insert(const_iterator hint, T&& value):
// iterator insert(const_iterator hint, init_type&& value);
//
// Inserts a value, using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search. Returns an iterator to the
// inserted element, or to the existing element that prevented the
// insertion.
//
// void insert(InputIterator first, InputIterator last):
//
// Inserts a range of values [`first`, `last`).
//
// NOTE: Although the STL does not specify which element may be inserted if
// multiple keys compare equivalently, for `flat_hash_map` we guarantee the
// first match is inserted.
//
// void insert(std::initializer_list<init_type> ilist):
//
// Inserts the elements within the initializer list `ilist`.
//
// NOTE: Although the STL does not specify which element may be inserted if
// multiple keys compare equivalently within the initializer list, for
// `flat_hash_map` we guarantee the first match is inserted.
using Base::insert;
// flat_hash_map::insert_or_assign()
//
// Inserts an element of the specified value into the `flat_hash_map` provided
// that a value with the given key does not already exist, or replaces it with
// the element value if a key for that value already exists, returning an
// iterator pointing to the newly inserted element. If rehashing occurs due
// to the insertion, all existing iterators are invalidated. Overloads are
// listed below.
//
// pair<iterator, bool> insert_or_assign(const init_type& k, T&& obj):
// pair<iterator, bool> insert_or_assign(init_type&& k, T&& obj):
//
// Inserts/Assigns (or moves) the element of the specified key into the
// `flat_hash_map`.
//
// iterator insert_or_assign(const_iterator hint,
// const init_type& k, T&& obj):
// iterator insert_or_assign(const_iterator hint, init_type&& k, T&& obj):
//
// Inserts/Assigns (or moves) the element of the specified key into the
// `flat_hash_map` using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search.
using Base::insert_or_assign;
// flat_hash_map::emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `flat_hash_map`, provided that no element with the given key
// already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately. Prefer `try_emplace()` unless your key is not
// copyable or moveable.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
using Base::emplace;
// flat_hash_map::emplace_hint()
//
// Inserts an element of the specified value by constructing it in-place
// within the `flat_hash_map`, using the position of `hint` as a non-binding
// suggestion for where to begin the insertion search, and only inserts
// provided that no element with the given key already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately. Prefer `try_emplace()` unless your key is not
// copyable or moveable.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
using Base::emplace_hint;
// flat_hash_map::try_emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `flat_hash_map`, provided that no element with the given key
// already exists. Unlike `emplace()`, if an element with the given key
// already exists, we guarantee that no element is constructed.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
// Overloads are listed below.
//
// pair<iterator, bool> try_emplace(const key_type& k, Args&&... args):
// pair<iterator, bool> try_emplace(key_type&& k, Args&&... args):
//
// Inserts (via copy or move) the element of the specified key into the
// `flat_hash_map`.
//
// iterator try_emplace(const_iterator hint,
// const key_type& k, Args&&... args):
// iterator try_emplace(const_iterator hint, key_type&& k, Args&&... args):
//
// Inserts (via copy or move) the element of the specified key into the
// `flat_hash_map` using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search.
//
// All `try_emplace()` overloads make the same guarantees regarding rvalue
// arguments as `std::unordered_map::try_emplace()`, namely that these
// functions will not move from rvalue arguments if insertions do not happen.
using Base::try_emplace;
// flat_hash_map::extract()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle. Overloads are listed below.
//
// node_type extract(const_iterator position):
//
// Extracts the key,value pair of the element at the indicated position and
// returns a node handle owning that extracted data.
//
// node_type extract(const key_type& x):
//
// Extracts the key,value pair of the element with a key matching the passed
// key value and returns a node handle owning that extracted data. If the
// `flat_hash_map` does not contain an element with a matching key, this
// function returns an empty node handle.
//
// NOTE: when compiled in an earlier version of C++ than C++17,
// `node_type::key()` returns a const reference to the key instead of a
// mutable reference. We cannot safely return a mutable reference without
// std::launder (which is not available before C++17).
using Base::extract;
// flat_hash_map::merge()
//
// Extracts elements from a given `source` flat hash map into this
// `flat_hash_map`. If the destination `flat_hash_map` already contains an
// element with an equivalent key, that element is not extracted.
using Base::merge;
// flat_hash_map::swap(flat_hash_map& other)
//
// Exchanges the contents of this `flat_hash_map` with those of the `other`
// flat hash map, avoiding invocation of any move, copy, or swap operations on
// individual elements.
//
// All iterators and references on the `flat_hash_map` remain valid, excepting
// for the past-the-end iterator, which is invalidated.
//
// `swap()` requires that the flat hash map's hashing and key equivalence
// functions be Swappable, and are exchanged using unqualified calls to
// non-member `swap()`. If the map's allocator has
// `std::allocator_traits<allocator_type>::propagate_on_container_swap::value`
// set to `true`, the allocators are also exchanged using an unqualified call
// to non-member `swap()`; otherwise, the allocators are not swapped.
using Base::swap;
// flat_hash_map::rehash(count)
//
// Rehashes the `flat_hash_map`, setting the number of slots to be at least
// the passed value. If the new number of slots increases the load factor more
// than the current maximum load factor
// (`count` < `size()` / `max_load_factor()`), then the new number of slots
// will be at least `size()` / `max_load_factor()`.
//
// To force a rehash, pass rehash(0).
//
// NOTE: unlike behavior in `std::unordered_map`, references are also
// invalidated upon a `rehash()`.
using Base::rehash;
// flat_hash_map::reserve(count)
//
// Sets the number of slots in the `flat_hash_map` to the number needed to
// accommodate at least `count` total elements without exceeding the current
// maximum load factor, and may rehash the container if needed.
using Base::reserve;
// flat_hash_map::at()
//
// Returns a reference to the mapped value of the element with key equivalent
// to the passed key.
using Base::at;
// flat_hash_map::contains()
//
// Determines whether an element with a key comparing equal to the given `key`
// exists within the `flat_hash_map`, returning `true` if so or `false`
// otherwise.
using Base::contains;
// flat_hash_map::count(const Key& key) const
//
// Returns the number of elements with a key comparing equal to the given
// `key` within the `flat_hash_map`. note that this function will return
// either `1` or `0` since duplicate keys are not allowed within a
// `flat_hash_map`.
using Base::count;
// flat_hash_map::equal_range()
//
// Returns a closed range [first, last], defined by a `std::pair` of two
// iterators, containing all elements with the passed key in the
// `flat_hash_map`.
using Base::equal_range;
// flat_hash_map::find()
//
// Finds an element with the passed `key` within the `flat_hash_map`.
using Base::find;
// flat_hash_map::operator[]()
//
// Returns a reference to the value mapped to the passed key within the
// `flat_hash_map`, performing an `insert()` if the key does not already
// exist.
//
// If an insertion occurs and results in a rehashing of the container, all
// iterators are invalidated. Otherwise iterators are not affected and
// references are not invalidated. Overloads are listed below.
//
// T& operator[](const Key& key):
//
// Inserts an init_type object constructed in-place if the element with the
// given key does not exist.
//
// T& operator[](Key&& key):
//
// Inserts an init_type object constructed in-place provided that an element
// with the given key does not exist.
using Base::operator[];
// flat_hash_map::bucket_count()
//
// Returns the number of "buckets" within the `flat_hash_map`. Note that
// because a flat hash map contains all elements within its internal storage,
// this value simply equals the current capacity of the `flat_hash_map`.
using Base::bucket_count;
// flat_hash_map::load_factor()
//
// Returns the current load factor of the `flat_hash_map` (the average number
// of slots occupied with a value within the hash map).
using Base::load_factor;
// flat_hash_map::max_load_factor()
//
// Manages the maximum load factor of the `flat_hash_map`. Overloads are
// listed below.
//
// float flat_hash_map::max_load_factor()
//
// Returns the current maximum load factor of the `flat_hash_map`.
//
// void flat_hash_map::max_load_factor(float ml)
//
// Sets the maximum load factor of the `flat_hash_map` to the passed value.
//
// NOTE: This overload is provided only for API compatibility with the STL;
// `flat_hash_map` will ignore any set load factor and manage its rehashing
// internally as an implementation detail.
using Base::max_load_factor;
// flat_hash_map::get_allocator()
//
// Returns the allocator function associated with this `flat_hash_map`.
using Base::get_allocator;
// flat_hash_map::hash_function()
//
// Returns the hashing function used to hash the keys within this
// `flat_hash_map`.
using Base::hash_function;
// flat_hash_map::key_eq()
//
// Returns the function used for comparing keys equality.
using Base::key_eq;
};
// erase_if(flat_hash_map<>, Pred)
//
// Erases all elements that satisfy the predicate `pred` from the container `c`.
// Returns the number of erased elements.
template <typename K, typename V, typename H, typename E, typename A,
typename Predicate>
typename flat_hash_map<K, V, H, E, A>::size_type erase_if(
flat_hash_map<K, V, H, E, A>& c, Predicate pred) {
return container_internal::EraseIf(pred, &c);
}
namespace container_internal {
template <class K, class V>
struct FlatHashMapPolicy {
using slot_policy = container_internal::map_slot_policy<K, V>;
using slot_type = typename slot_policy::slot_type;
using key_type = K;
using mapped_type = V;
using init_type = std::pair</*non const*/ key_type, mapped_type>;
template <class Allocator, class... Args>
static void construct(Allocator* alloc, slot_type* slot, Args&&... args) {
slot_policy::construct(alloc, slot, std::forward<Args>(args)...);
}
template <class Allocator>
static void destroy(Allocator* alloc, slot_type* slot) {
slot_policy::destroy(alloc, slot);
}
template <class Allocator>
static auto transfer(Allocator* alloc, slot_type* new_slot,
slot_type* old_slot) {
return slot_policy::transfer(alloc, new_slot, old_slot);
}
template <class F, class... Args>
static decltype(absl::container_internal::DecomposePair(
std::declval<F>(), std::declval<Args>()...))
apply(F&& f, Args&&... args) {
return absl::container_internal::DecomposePair(std::forward<F>(f),
std::forward<Args>(args)...);
}
static size_t space_used(const slot_type*) { return 0; }
static std::pair<const K, V>& element(slot_type* slot) { return slot->value; }
static V& value(std::pair<const K, V>* kv) { return kv->second; }
static const V& value(const std::pair<const K, V>* kv) { return kv->second; }
};
} // namespace container_internal
namespace container_algorithm_internal {
// Specialization of trait in absl/algorithm/container.h
template <class Key, class T, class Hash, class KeyEqual, class Allocator>
struct IsUnorderedContainer<
absl::flat_hash_map<Key, T, Hash, KeyEqual, Allocator>> : std::true_type {};
} // namespace container_algorithm_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_FLAT_HASH_MAP_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: flat_hash_set.h
// -----------------------------------------------------------------------------
//
// An `absl::flat_hash_set<T>` is an unordered associative container designed to
// be a more efficient replacement for `std::unordered_set`. Like
// `unordered_set`, search, insertion, and deletion of set elements can be done
// as an `O(1)` operation. However, `flat_hash_set` (and other unordered
// associative containers known as the collection of Abseil "Swiss tables")
// contain other optimizations that result in both memory and computation
// advantages.
//
// In most cases, your default choice for a hash set should be a set of type
// `flat_hash_set`.
#ifndef ABSL_CONTAINER_FLAT_HASH_SET_H_
#define ABSL_CONTAINER_FLAT_HASH_SET_H_
#include <type_traits>
#include <utility>
#include "absl/algorithm/container.h"
#include "absl/base/macros.h"
#include "absl/container/internal/container_memory.h"
#include "absl/container/internal/hash_function_defaults.h" // IWYU pragma: export
#include "absl/container/internal/raw_hash_set.h" // IWYU pragma: export
#include "absl/memory/memory.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <typename T>
struct FlatHashSetPolicy;
} // namespace container_internal
// -----------------------------------------------------------------------------
// absl::flat_hash_set
// -----------------------------------------------------------------------------
//
// An `absl::flat_hash_set<T>` is an unordered associative container which has
// been optimized for both speed and memory footprint in most common use cases.
// Its interface is similar to that of `std::unordered_set<T>` with the
// following notable differences:
//
// * Requires keys that are CopyConstructible
// * Supports heterogeneous lookup, through `find()` and `insert()`, provided
// that the set is provided a compatible heterogeneous hashing function and
// equality operator.
// * Invalidates any references and pointers to elements within the table after
// `rehash()` and when the table is moved.
// * Contains a `capacity()` member function indicating the number of element
// slots (open, deleted, and empty) within the hash set.
// * Returns `void` from the `erase(iterator)` overload.
//
// By default, `flat_hash_set` uses the `absl::Hash` hashing framework. All
// fundamental and Abseil types that support the `absl::Hash` framework have a
// compatible equality operator for comparing insertions into `flat_hash_set`.
// If your type is not yet supported by the `absl::Hash` framework, see
// absl/hash/hash.h for information on extending Abseil hashing to user-defined
// types.
//
// Using `absl::flat_hash_set` at interface boundaries in dynamically loaded
// libraries (e.g. .dll, .so) is unsupported due to way `absl::Hash` values may
// be randomized across dynamically loaded libraries.
//
// NOTE: A `flat_hash_set` stores its keys directly inside its implementation
// array to avoid memory indirection. Because a `flat_hash_set` is designed to
// move data when rehashed, set keys will not retain pointer stability. If you
// require pointer stability, consider using
// `absl::flat_hash_set<std::unique_ptr<T>>`. If your type is not moveable and
// you require pointer stability, consider `absl::node_hash_set` instead.
//
// Example:
//
// // Create a flat hash set of three strings
// absl::flat_hash_set<std::string> ducks =
// {"huey", "dewey", "louie"};
//
// // Insert a new element into the flat hash set
// ducks.insert("donald");
//
// // Force a rehash of the flat hash set
// ducks.rehash(0);
//
// // See if "dewey" is present
// if (ducks.contains("dewey")) {
// std::cout << "We found dewey!" << std::endl;
// }
template <class T, class Hash = absl::container_internal::hash_default_hash<T>,
class Eq = absl::container_internal::hash_default_eq<T>,
class Allocator = std::allocator<T>>
class flat_hash_set
: public absl::container_internal::raw_hash_set<
absl::container_internal::FlatHashSetPolicy<T>, Hash, Eq, Allocator> {
using Base = typename flat_hash_set::raw_hash_set;
public:
// Constructors and Assignment Operators
//
// A flat_hash_set supports the same overload set as `std::unordered_set`
// for construction and assignment:
//
// * Default constructor
//
// // No allocation for the table's elements is made.
// absl::flat_hash_set<std::string> set1;
//
// * Initializer List constructor
//
// absl::flat_hash_set<std::string> set2 =
// {{"huey"}, {"dewey"}, {"louie"},};
//
// * Copy constructor
//
// absl::flat_hash_set<std::string> set3(set2);
//
// * Copy assignment operator
//
// // Hash functor and Comparator are copied as well
// absl::flat_hash_set<std::string> set4;
// set4 = set3;
//
// * Move constructor
//
// // Move is guaranteed efficient
// absl::flat_hash_set<std::string> set5(std::move(set4));
//
// * Move assignment operator
//
// // May be efficient if allocators are compatible
// absl::flat_hash_set<std::string> set6;
// set6 = std::move(set5);
//
// * Range constructor
//
// std::vector<std::string> v = {"a", "b"};
// absl::flat_hash_set<std::string> set7(v.begin(), v.end());
flat_hash_set() {}
using Base::Base;
// flat_hash_set::begin()
//
// Returns an iterator to the beginning of the `flat_hash_set`.
using Base::begin;
// flat_hash_set::cbegin()
//
// Returns a const iterator to the beginning of the `flat_hash_set`.
using Base::cbegin;
// flat_hash_set::cend()
//
// Returns a const iterator to the end of the `flat_hash_set`.
using Base::cend;
// flat_hash_set::end()
//
// Returns an iterator to the end of the `flat_hash_set`.
using Base::end;
// flat_hash_set::capacity()
//
// Returns the number of element slots (assigned, deleted, and empty)
// available within the `flat_hash_set`.
//
// NOTE: this member function is particular to `absl::flat_hash_set` and is
// not provided in the `std::unordered_set` API.
using Base::capacity;
// flat_hash_set::empty()
//
// Returns whether or not the `flat_hash_set` is empty.
using Base::empty;
// flat_hash_set::max_size()
//
// Returns the largest theoretical possible number of elements within a
// `flat_hash_set` under current memory constraints. This value can be thought
// of the largest value of `std::distance(begin(), end())` for a
// `flat_hash_set<T>`.
using Base::max_size;
// flat_hash_set::size()
//
// Returns the number of elements currently within the `flat_hash_set`.
using Base::size;
// flat_hash_set::clear()
//
// Removes all elements from the `flat_hash_set`. Invalidates any references,
// pointers, or iterators referring to contained elements.
//
// NOTE: this operation may shrink the underlying buffer. To avoid shrinking
// the underlying buffer call `erase(begin(), end())`.
using Base::clear;
// flat_hash_set::erase()
//
// Erases elements within the `flat_hash_set`. Erasing does not trigger a
// rehash. Overloads are listed below.
//
// void erase(const_iterator pos):
//
// Erases the element at `position` of the `flat_hash_set`, returning
// `void`.
//
// NOTE: returning `void` in this case is different than that of STL
// containers in general and `std::unordered_set` in particular (which
// return an iterator to the element following the erased element). If that
// iterator is needed, simply post increment the iterator:
//
// set.erase(it++);
//
// iterator erase(const_iterator first, const_iterator last):
//
// Erases the elements in the open interval [`first`, `last`), returning an
// iterator pointing to `last`. The special case of calling
// `erase(begin(), end())` resets the reserved growth such that if
// `reserve(N)` has previously been called and there has been no intervening
// call to `clear()`, then after calling `erase(begin(), end())`, it is safe
// to assume that inserting N elements will not cause a rehash.
//
// size_type erase(const key_type& key):
//
// Erases the element with the matching key, if it exists, returning the
// number of elements erased (0 or 1).
using Base::erase;
// flat_hash_set::insert()
//
// Inserts an element of the specified value into the `flat_hash_set`,
// returning an iterator pointing to the newly inserted element, provided that
// an element with the given key does not already exist. If rehashing occurs
// due to the insertion, all iterators are invalidated. Overloads are listed
// below.
//
// std::pair<iterator,bool> insert(const T& value):
//
// Inserts a value into the `flat_hash_set`. Returns a pair consisting of an
// iterator to the inserted element (or to the element that prevented the
// insertion) and a bool denoting whether the insertion took place.
//
// std::pair<iterator,bool> insert(T&& value):
//
// Inserts a moveable value into the `flat_hash_set`. Returns a pair
// consisting of an iterator to the inserted element (or to the element that
// prevented the insertion) and a bool denoting whether the insertion took
// place.
//
// iterator insert(const_iterator hint, const T& value):
// iterator insert(const_iterator hint, T&& value):
//
// Inserts a value, using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search. Returns an iterator to the
// inserted element, or to the existing element that prevented the
// insertion.
//
// void insert(InputIterator first, InputIterator last):
//
// Inserts a range of values [`first`, `last`).
//
// NOTE: Although the STL does not specify which element may be inserted if
// multiple keys compare equivalently, for `flat_hash_set` we guarantee the
// first match is inserted.
//
// void insert(std::initializer_list<T> ilist):
//
// Inserts the elements within the initializer list `ilist`.
//
// NOTE: Although the STL does not specify which element may be inserted if
// multiple keys compare equivalently within the initializer list, for
// `flat_hash_set` we guarantee the first match is inserted.
using Base::insert;
// flat_hash_set::emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `flat_hash_set`, provided that no element with the given key
// already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
using Base::emplace;
// flat_hash_set::emplace_hint()
//
// Inserts an element of the specified value by constructing it in-place
// within the `flat_hash_set`, using the position of `hint` as a non-binding
// suggestion for where to begin the insertion search, and only inserts
// provided that no element with the given key already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
using Base::emplace_hint;
// flat_hash_set::extract()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle. Overloads are listed below.
//
// node_type extract(const_iterator position):
//
// Extracts the element at the indicated position and returns a node handle
// owning that extracted data.
//
// node_type extract(const key_type& x):
//
// Extracts the element with the key matching the passed key value and
// returns a node handle owning that extracted data. If the `flat_hash_set`
// does not contain an element with a matching key, this function returns an
// empty node handle.
using Base::extract;
// flat_hash_set::merge()
//
// Extracts elements from a given `source` flat hash set into this
// `flat_hash_set`. If the destination `flat_hash_set` already contains an
// element with an equivalent key, that element is not extracted.
using Base::merge;
// flat_hash_set::swap(flat_hash_set& other)
//
// Exchanges the contents of this `flat_hash_set` with those of the `other`
// flat hash set, avoiding invocation of any move, copy, or swap operations on
// individual elements.
//
// All iterators and references on the `flat_hash_set` remain valid, excepting
// for the past-the-end iterator, which is invalidated.
//
// `swap()` requires that the flat hash set's hashing and key equivalence
// functions be Swappable, and are exchanged using unqualified calls to
// non-member `swap()`. If the set's allocator has
// `std::allocator_traits<allocator_type>::propagate_on_container_swap::value`
// set to `true`, the allocators are also exchanged using an unqualified call
// to non-member `swap()`; otherwise, the allocators are not swapped.
using Base::swap;
// flat_hash_set::rehash(count)
//
// Rehashes the `flat_hash_set`, setting the number of slots to be at least
// the passed value. If the new number of slots increases the load factor more
// than the current maximum load factor
// (`count` < `size()` / `max_load_factor()`), then the new number of slots
// will be at least `size()` / `max_load_factor()`.
//
// To force a rehash, pass rehash(0).
//
// NOTE: unlike behavior in `std::unordered_set`, references are also
// invalidated upon a `rehash()`.
using Base::rehash;
// flat_hash_set::reserve(count)
//
// Sets the number of slots in the `flat_hash_set` to the number needed to
// accommodate at least `count` total elements without exceeding the current
// maximum load factor, and may rehash the container if needed.
using Base::reserve;
// flat_hash_set::contains()
//
// Determines whether an element comparing equal to the given `key` exists
// within the `flat_hash_set`, returning `true` if so or `false` otherwise.
using Base::contains;
// flat_hash_set::count(const Key& key) const
//
// Returns the number of elements comparing equal to the given `key` within
// the `flat_hash_set`. note that this function will return either `1` or `0`
// since duplicate elements are not allowed within a `flat_hash_set`.
using Base::count;
// flat_hash_set::equal_range()
//
// Returns a closed range [first, last], defined by a `std::pair` of two
// iterators, containing all elements with the passed key in the
// `flat_hash_set`.
using Base::equal_range;
// flat_hash_set::find()
//
// Finds an element with the passed `key` within the `flat_hash_set`.
using Base::find;
// flat_hash_set::bucket_count()
//
// Returns the number of "buckets" within the `flat_hash_set`. Note that
// because a flat hash set contains all elements within its internal storage,
// this value simply equals the current capacity of the `flat_hash_set`.
using Base::bucket_count;
// flat_hash_set::load_factor()
//
// Returns the current load factor of the `flat_hash_set` (the average number
// of slots occupied with a value within the hash set).
using Base::load_factor;
// flat_hash_set::max_load_factor()
//
// Manages the maximum load factor of the `flat_hash_set`. Overloads are
// listed below.
//
// float flat_hash_set::max_load_factor()
//
// Returns the current maximum load factor of the `flat_hash_set`.
//
// void flat_hash_set::max_load_factor(float ml)
//
// Sets the maximum load factor of the `flat_hash_set` to the passed value.
//
// NOTE: This overload is provided only for API compatibility with the STL;
// `flat_hash_set` will ignore any set load factor and manage its rehashing
// internally as an implementation detail.
using Base::max_load_factor;
// flat_hash_set::get_allocator()
//
// Returns the allocator function associated with this `flat_hash_set`.
using Base::get_allocator;
// flat_hash_set::hash_function()
//
// Returns the hashing function used to hash the keys within this
// `flat_hash_set`.
using Base::hash_function;
// flat_hash_set::key_eq()
//
// Returns the function used for comparing keys equality.
using Base::key_eq;
};
// erase_if(flat_hash_set<>, Pred)
//
// Erases all elements that satisfy the predicate `pred` from the container `c`.
// Returns the number of erased elements.
template <typename T, typename H, typename E, typename A, typename Predicate>
typename flat_hash_set<T, H, E, A>::size_type erase_if(
flat_hash_set<T, H, E, A>& c, Predicate pred) {
return container_internal::EraseIf(pred, &c);
}
namespace container_internal {
template <class T>
struct FlatHashSetPolicy {
using slot_type = T;
using key_type = T;
using init_type = T;
using constant_iterators = std::true_type;
template <class Allocator, class... Args>
static void construct(Allocator* alloc, slot_type* slot, Args&&... args) {
absl::allocator_traits<Allocator>::construct(*alloc, slot,
std::forward<Args>(args)...);
}
template <class Allocator>
static void destroy(Allocator* alloc, slot_type* slot) {
absl::allocator_traits<Allocator>::destroy(*alloc, slot);
}
static T& element(slot_type* slot) { return *slot; }
template <class F, class... Args>
static decltype(absl::container_internal::DecomposeValue(
std::declval<F>(), std::declval<Args>()...))
apply(F&& f, Args&&... args) {
return absl::container_internal::DecomposeValue(
std::forward<F>(f), std::forward<Args>(args)...);
}
static size_t space_used(const T*) { return 0; }
};
} // namespace container_internal
namespace container_algorithm_internal {
// Specialization of trait in absl/algorithm/container.h
template <class Key, class Hash, class KeyEqual, class Allocator>
struct IsUnorderedContainer<absl::flat_hash_set<Key, Hash, KeyEqual, Allocator>>
: std::true_type {};
} // namespace container_algorithm_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_FLAT_HASH_SET_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_BTREE_CONTAINER_H_
#define ABSL_CONTAINER_INTERNAL_BTREE_CONTAINER_H_
#include <algorithm>
#include <initializer_list>
#include <iterator>
#include <utility>
#include "absl/base/attributes.h"
#include "absl/base/internal/throw_delegate.h"
#include "absl/container/internal/btree.h" // IWYU pragma: export
#include "absl/container/internal/common.h"
#include "absl/memory/memory.h"
#include "absl/meta/type_traits.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// A common base class for btree_set, btree_map, btree_multiset, and
// btree_multimap.
template <typename Tree>
class btree_container {
using params_type = typename Tree::params_type;
protected:
// Alias used for heterogeneous lookup functions.
// `key_arg<K>` evaluates to `K` when the functors are transparent and to
// `key_type` otherwise. It permits template argument deduction on `K` for the
// transparent case.
template <class K>
using key_arg =
typename KeyArg<params_type::kIsKeyCompareTransparent>::template type<
K, typename Tree::key_type>;
public:
using key_type = typename Tree::key_type;
using value_type = typename Tree::value_type;
using size_type = typename Tree::size_type;
using difference_type = typename Tree::difference_type;
using key_compare = typename Tree::original_key_compare;
using value_compare = typename Tree::value_compare;
using allocator_type = typename Tree::allocator_type;
using reference = typename Tree::reference;
using const_reference = typename Tree::const_reference;
using pointer = typename Tree::pointer;
using const_pointer = typename Tree::const_pointer;
using iterator = typename Tree::iterator;
using const_iterator = typename Tree::const_iterator;
using reverse_iterator = typename Tree::reverse_iterator;
using const_reverse_iterator = typename Tree::const_reverse_iterator;
using node_type = typename Tree::node_handle_type;
struct extract_and_get_next_return_type {
node_type node;
iterator next;
};
// Constructors/assignments.
btree_container() : tree_(key_compare(), allocator_type()) {}
explicit btree_container(const key_compare &comp,
const allocator_type &alloc = allocator_type())
: tree_(comp, alloc) {}
explicit btree_container(const allocator_type &alloc)
: tree_(key_compare(), alloc) {}
btree_container(const btree_container &other)
: btree_container(other, absl::allocator_traits<allocator_type>::
select_on_container_copy_construction(
other.get_allocator())) {}
btree_container(const btree_container &other, const allocator_type &alloc)
: tree_(other.tree_, alloc) {}
btree_container(btree_container &&other) noexcept(
std::is_nothrow_move_constructible<Tree>::value) = default;
btree_container(btree_container &&other, const allocator_type &alloc)
: tree_(std::move(other.tree_), alloc) {}
btree_container &operator=(const btree_container &other) = default;
btree_container &operator=(btree_container &&other) noexcept(
std::is_nothrow_move_assignable<Tree>::value) = default;
// Iterator routines.
iterator begin() ABSL_ATTRIBUTE_LIFETIME_BOUND { return tree_.begin(); }
const_iterator begin() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.begin();
}
const_iterator cbegin() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.begin();
}
iterator end() ABSL_ATTRIBUTE_LIFETIME_BOUND { return tree_.end(); }
const_iterator end() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.end();
}
const_iterator cend() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.end();
}
reverse_iterator rbegin() ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.rbegin();
}
const_reverse_iterator rbegin() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.rbegin();
}
const_reverse_iterator crbegin() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.rbegin();
}
reverse_iterator rend() ABSL_ATTRIBUTE_LIFETIME_BOUND { return tree_.rend(); }
const_reverse_iterator rend() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.rend();
}
const_reverse_iterator crend() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.rend();
}
// Lookup routines.
template <typename K = key_type>
size_type count(const key_arg<K> &key) const {
auto equal_range = this->equal_range(key);
return equal_range.second - equal_range.first;
}
template <typename K = key_type>
iterator find(const key_arg<K> &key) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.find(key);
}
template <typename K = key_type>
const_iterator find(const key_arg<K> &key) const
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.find(key);
}
template <typename K = key_type>
bool contains(const key_arg<K> &key) const {
return find(key) != end();
}
template <typename K = key_type>
iterator lower_bound(const key_arg<K> &key) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.lower_bound(key);
}
template <typename K = key_type>
const_iterator lower_bound(const key_arg<K> &key) const
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.lower_bound(key);
}
template <typename K = key_type>
iterator upper_bound(const key_arg<K> &key) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.upper_bound(key);
}
template <typename K = key_type>
const_iterator upper_bound(const key_arg<K> &key) const
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.upper_bound(key);
}
template <typename K = key_type>
std::pair<iterator, iterator> equal_range(const key_arg<K> &key)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.equal_range(key);
}
template <typename K = key_type>
std::pair<const_iterator, const_iterator> equal_range(
const key_arg<K> &key) const ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.equal_range(key);
}
// Deletion routines. Note that there is also a deletion routine that is
// specific to btree_set_container/btree_multiset_container.
// Erase the specified iterator from the btree. The iterator must be valid
// (i.e. not equal to end()). Return an iterator pointing to the node after
// the one that was erased (or end() if none exists).
iterator erase(const_iterator iter) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.erase(iterator(iter));
}
iterator erase(iterator iter) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.erase(iter);
}
iterator erase(const_iterator first,
const_iterator last) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return tree_.erase_range(iterator(first), iterator(last)).second;
}
template <typename K = key_type>
size_type erase(const key_arg<K> &key) {
auto equal_range = this->equal_range(key);
return tree_.erase_range(equal_range.first, equal_range.second).first;
}
// Extract routines.
extract_and_get_next_return_type extract_and_get_next(const_iterator position)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
// Use Construct instead of Transfer because the rebalancing code will
// destroy the slot later.
// Note: we rely on erase() taking place after Construct().
return {CommonAccess::Construct<node_type>(get_allocator(),
iterator(position).slot()),
erase(position)};
}
node_type extract(iterator position) {
// Use Construct instead of Transfer because the rebalancing code will
// destroy the slot later.
auto node =
CommonAccess::Construct<node_type>(get_allocator(), position.slot());
erase(position);
return node;
}
node_type extract(const_iterator position) {
return extract(iterator(position));
}
// Utility routines.
ABSL_ATTRIBUTE_REINITIALIZES void clear() { tree_.clear(); }
void swap(btree_container &other) { tree_.swap(other.tree_); }
void verify() const { tree_.verify(); }
// Size routines.
size_type size() const { return tree_.size(); }
size_type max_size() const { return tree_.max_size(); }
bool empty() const { return tree_.empty(); }
friend bool operator==(const btree_container &x, const btree_container &y) {
if (x.size() != y.size()) return false;
return std::equal(x.begin(), x.end(), y.begin());
}
friend bool operator!=(const btree_container &x, const btree_container &y) {
return !(x == y);
}
friend bool operator<(const btree_container &x, const btree_container &y) {
return std::lexicographical_compare(x.begin(), x.end(), y.begin(), y.end());
}
friend bool operator>(const btree_container &x, const btree_container &y) {
return y < x;
}
friend bool operator<=(const btree_container &x, const btree_container &y) {
return !(y < x);
}
friend bool operator>=(const btree_container &x, const btree_container &y) {
return !(x < y);
}
// The allocator used by the btree.
allocator_type get_allocator() const { return tree_.get_allocator(); }
// The key comparator used by the btree.
key_compare key_comp() const { return key_compare(tree_.key_comp()); }
value_compare value_comp() const { return tree_.value_comp(); }
// Support absl::Hash.
template <typename State>
friend State AbslHashValue(State h, const btree_container &b) {
for (const auto &v : b) {
h = State::combine(std::move(h), v);
}
return State::combine(std::move(h), b.size());
}
protected:
friend struct btree_access;
Tree tree_;
};
// A common base class for btree_set and btree_map.
template <typename Tree>
class btree_set_container : public btree_container<Tree> {
using super_type = btree_container<Tree>;
using params_type = typename Tree::params_type;
using init_type = typename params_type::init_type;
using is_key_compare_to = typename params_type::is_key_compare_to;
friend class BtreeNodePeer;
protected:
template <class K>
using key_arg = typename super_type::template key_arg<K>;
public:
using key_type = typename Tree::key_type;
using value_type = typename Tree::value_type;
using size_type = typename Tree::size_type;
using key_compare = typename Tree::original_key_compare;
using allocator_type = typename Tree::allocator_type;
using iterator = typename Tree::iterator;
using const_iterator = typename Tree::const_iterator;
using node_type = typename super_type::node_type;
using insert_return_type = InsertReturnType<iterator, node_type>;
// Inherit constructors.
using super_type::super_type;
btree_set_container() {}
// Range constructors.
template <class InputIterator>
btree_set_container(InputIterator b, InputIterator e,
const key_compare &comp = key_compare(),
const allocator_type &alloc = allocator_type())
: super_type(comp, alloc) {
insert(b, e);
}
template <class InputIterator>
btree_set_container(InputIterator b, InputIterator e,
const allocator_type &alloc)
: btree_set_container(b, e, key_compare(), alloc) {}
// Initializer list constructors.
btree_set_container(std::initializer_list<init_type> init,
const key_compare &comp = key_compare(),
const allocator_type &alloc = allocator_type())
: btree_set_container(init.begin(), init.end(), comp, alloc) {}
btree_set_container(std::initializer_list<init_type> init,
const allocator_type &alloc)
: btree_set_container(init.begin(), init.end(), alloc) {}
// Insertion routines.
std::pair<iterator, bool> insert(const value_type &v)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return this->tree_.insert_unique(params_type::key(v), v);
}
std::pair<iterator, bool> insert(value_type &&v)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return this->tree_.insert_unique(params_type::key(v), std::move(v));
}
template <typename... Args>
std::pair<iterator, bool> emplace(Args &&...args)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
// Use a node handle to manage a temp slot.
auto node = CommonAccess::Construct<node_type>(this->get_allocator(),
std::forward<Args>(args)...);
auto *slot = CommonAccess::GetSlot(node);
return this->tree_.insert_unique(params_type::key(slot), slot);
}
iterator insert(const_iterator hint,
const value_type &v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return this->tree_
.insert_hint_unique(iterator(hint), params_type::key(v), v)
.first;
}
iterator insert(const_iterator hint,
value_type &&v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return this->tree_
.insert_hint_unique(iterator(hint), params_type::key(v), std::move(v))
.first;
}
template <typename... Args>
iterator emplace_hint(const_iterator hint,
Args &&...args) ABSL_ATTRIBUTE_LIFETIME_BOUND {
// Use a node handle to manage a temp slot.
auto node = CommonAccess::Construct<node_type>(this->get_allocator(),
std::forward<Args>(args)...);
auto *slot = CommonAccess::GetSlot(node);
return this->tree_
.insert_hint_unique(iterator(hint), params_type::key(slot), slot)
.first;
}
template <typename InputIterator>
void insert(InputIterator b, InputIterator e) {
this->tree_.insert_iterator_unique(b, e, 0);
}
void insert(std::initializer_list<init_type> init) {
this->tree_.insert_iterator_unique(init.begin(), init.end(), 0);
}
insert_return_type insert(node_type &&node) ABSL_ATTRIBUTE_LIFETIME_BOUND {
if (!node) return {this->end(), false, node_type()};
std::pair<iterator, bool> res =
this->tree_.insert_unique(params_type::key(CommonAccess::GetSlot(node)),
CommonAccess::GetSlot(node));
if (res.second) {
CommonAccess::Destroy(&node);
return {res.first, true, node_type()};
} else {
return {res.first, false, std::move(node)};
}
}
iterator insert(const_iterator hint,
node_type &&node) ABSL_ATTRIBUTE_LIFETIME_BOUND {
if (!node) return this->end();
std::pair<iterator, bool> res = this->tree_.insert_hint_unique(
iterator(hint), params_type::key(CommonAccess::GetSlot(node)),
CommonAccess::GetSlot(node));
if (res.second) CommonAccess::Destroy(&node);
return res.first;
}
// Node extraction routines.
template <typename K = key_type>
node_type extract(const key_arg<K> &key) {
const std::pair<iterator, bool> lower_and_equal =
this->tree_.lower_bound_equal(key);
return lower_and_equal.second ? extract(lower_and_equal.first)
: node_type();
}
using super_type::extract;
// Merge routines.
// Moves elements from `src` into `this`. If the element already exists in
// `this`, it is left unmodified in `src`.
template <
typename T,
typename absl::enable_if_t<
absl::conjunction<
std::is_same<value_type, typename T::value_type>,
std::is_same<allocator_type, typename T::allocator_type>,
std::is_same<typename params_type::is_map_container,
typename T::params_type::is_map_container>>::value,
int> = 0>
void merge(btree_container<T> &src) { // NOLINT
for (auto src_it = src.begin(); src_it != src.end();) {
if (insert(std::move(params_type::element(src_it.slot()))).second) {
src_it = src.erase(src_it);
} else {
++src_it;
}
}
}
template <
typename T,
typename absl::enable_if_t<
absl::conjunction<
std::is_same<value_type, typename T::value_type>,
std::is_same<allocator_type, typename T::allocator_type>,
std::is_same<typename params_type::is_map_container,
typename T::params_type::is_map_container>>::value,
int> = 0>
void merge(btree_container<T> &&src) {
merge(src);
}
};
// Base class for btree_map.
template <typename Tree>
class btree_map_container : public btree_set_container<Tree> {
using super_type = btree_set_container<Tree>;
using params_type = typename Tree::params_type;
friend class BtreeNodePeer;
private:
template <class K>
using key_arg = typename super_type::template key_arg<K>;
public:
using key_type = typename Tree::key_type;
using mapped_type = typename params_type::mapped_type;
using value_type = typename Tree::value_type;
using key_compare = typename Tree::original_key_compare;
using allocator_type = typename Tree::allocator_type;
using iterator = typename Tree::iterator;
using const_iterator = typename Tree::const_iterator;
// Inherit constructors.
using super_type::super_type;
btree_map_container() {}
// Insertion routines.
// Note: the nullptr template arguments and extra `const M&` overloads allow
// for supporting bitfield arguments.
template <typename K = key_type, class M>
std::pair<iterator, bool> insert_or_assign(const key_arg<K> &k, const M &obj)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_impl(k, obj);
}
template <typename K = key_type, class M, K * = nullptr>
std::pair<iterator, bool> insert_or_assign(key_arg<K> &&k, const M &obj)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_impl(std::forward<K>(k), obj);
}
template <typename K = key_type, class M, M * = nullptr>
std::pair<iterator, bool> insert_or_assign(const key_arg<K> &k, M &&obj)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_impl(k, std::forward<M>(obj));
}
template <typename K = key_type, class M, K * = nullptr, M * = nullptr>
std::pair<iterator, bool> insert_or_assign(key_arg<K> &&k, M &&obj)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_impl(std::forward<K>(k), std::forward<M>(obj));
}
template <typename K = key_type, class M>
iterator insert_or_assign(const_iterator hint, const key_arg<K> &k,
const M &obj) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_hint_impl(hint, k, obj);
}
template <typename K = key_type, class M, K * = nullptr>
iterator insert_or_assign(const_iterator hint, key_arg<K> &&k,
const M &obj) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_hint_impl(hint, std::forward<K>(k), obj);
}
template <typename K = key_type, class M, M * = nullptr>
iterator insert_or_assign(const_iterator hint, const key_arg<K> &k,
M &&obj) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_hint_impl(hint, k, std::forward<M>(obj));
}
template <typename K = key_type, class M, K * = nullptr, M * = nullptr>
iterator insert_or_assign(const_iterator hint, key_arg<K> &&k,
M &&obj) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_hint_impl(hint, std::forward<K>(k),
std::forward<M>(obj));
}
template <typename K = key_type, typename... Args,
typename absl::enable_if_t<
!std::is_convertible<K, const_iterator>::value, int> = 0>
std::pair<iterator, bool> try_emplace(const key_arg<K> &k, Args &&...args)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace_impl(k, std::forward<Args>(args)...);
}
template <typename K = key_type, typename... Args,
typename absl::enable_if_t<
!std::is_convertible<K, const_iterator>::value, int> = 0>
std::pair<iterator, bool> try_emplace(key_arg<K> &&k, Args &&...args)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace_impl(std::forward<K>(k), std::forward<Args>(args)...);
}
template <typename K = key_type, typename... Args>
iterator try_emplace(const_iterator hint, const key_arg<K> &k,
Args &&...args) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace_hint_impl(hint, k, std::forward<Args>(args)...);
}
template <typename K = key_type, typename... Args>
iterator try_emplace(const_iterator hint, key_arg<K> &&k,
Args &&...args) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace_hint_impl(hint, std::forward<K>(k),
std::forward<Args>(args)...);
}
template <typename K = key_type>
mapped_type &operator[](const key_arg<K> &k) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace(k).first->second;
}
template <typename K = key_type>
mapped_type &operator[](key_arg<K> &&k) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace(std::forward<K>(k)).first->second;
}
template <typename K = key_type>
mapped_type &at(const key_arg<K> &key) ABSL_ATTRIBUTE_LIFETIME_BOUND {
auto it = this->find(key);
if (it == this->end())
base_internal::ThrowStdOutOfRange("absl::btree_map::at");
return it->second;
}
template <typename K = key_type>
const mapped_type &at(const key_arg<K> &key) const
ABSL_ATTRIBUTE_LIFETIME_BOUND {
auto it = this->find(key);
if (it == this->end())
base_internal::ThrowStdOutOfRange("absl::btree_map::at");
return it->second;
}
private:
// Note: when we call `std::forward<M>(obj)` twice, it's safe because
// insert_unique/insert_hint_unique are guaranteed to not consume `obj` when
// `ret.second` is false.
template <class K, class M>
std::pair<iterator, bool> insert_or_assign_impl(K &&k, M &&obj) {
const std::pair<iterator, bool> ret =
this->tree_.insert_unique(k, std::forward<K>(k), std::forward<M>(obj));
if (!ret.second) ret.first->second = std::forward<M>(obj);
return ret;
}
template <class K, class M>
iterator insert_or_assign_hint_impl(const_iterator hint, K &&k, M &&obj) {
const std::pair<iterator, bool> ret = this->tree_.insert_hint_unique(
iterator(hint), k, std::forward<K>(k), std::forward<M>(obj));
if (!ret.second) ret.first->second = std::forward<M>(obj);
return ret.first;
}
template <class K, class... Args>
std::pair<iterator, bool> try_emplace_impl(K &&k, Args &&... args) {
return this->tree_.insert_unique(
k, std::piecewise_construct, std::forward_as_tuple(std::forward<K>(k)),
std::forward_as_tuple(std::forward<Args>(args)...));
}
template <class K, class... Args>
iterator try_emplace_hint_impl(const_iterator hint, K &&k, Args &&... args) {
return this->tree_
.insert_hint_unique(iterator(hint), k, std::piecewise_construct,
std::forward_as_tuple(std::forward<K>(k)),
std::forward_as_tuple(std::forward<Args>(args)...))
.first;
}
};
// A common base class for btree_multiset and btree_multimap.
template <typename Tree>
class btree_multiset_container : public btree_container<Tree> {
using super_type = btree_container<Tree>;
using params_type = typename Tree::params_type;
using init_type = typename params_type::init_type;
using is_key_compare_to = typename params_type::is_key_compare_to;
friend class BtreeNodePeer;
template <class K>
using key_arg = typename super_type::template key_arg<K>;
public:
using key_type = typename Tree::key_type;
using value_type = typename Tree::value_type;
using size_type = typename Tree::size_type;
using key_compare = typename Tree::original_key_compare;
using allocator_type = typename Tree::allocator_type;
using iterator = typename Tree::iterator;
using const_iterator = typename Tree::const_iterator;
using node_type = typename super_type::node_type;
// Inherit constructors.
using super_type::super_type;
btree_multiset_container() {}
// Range constructors.
template <class InputIterator>
btree_multiset_container(InputIterator b, InputIterator e,
const key_compare &comp = key_compare(),
const allocator_type &alloc = allocator_type())
: super_type(comp, alloc) {
insert(b, e);
}
template <class InputIterator>
btree_multiset_container(InputIterator b, InputIterator e,
const allocator_type &alloc)
: btree_multiset_container(b, e, key_compare(), alloc) {}
// Initializer list constructors.
btree_multiset_container(std::initializer_list<init_type> init,
const key_compare &comp = key_compare(),
const allocator_type &alloc = allocator_type())
: btree_multiset_container(init.begin(), init.end(), comp, alloc) {}
btree_multiset_container(std::initializer_list<init_type> init,
const allocator_type &alloc)
: btree_multiset_container(init.begin(), init.end(), alloc) {}
// Insertion routines.
iterator insert(const value_type &v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return this->tree_.insert_multi(v);
}
iterator insert(value_type &&v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return this->tree_.insert_multi(std::move(v));
}
iterator insert(const_iterator hint,
const value_type &v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return this->tree_.insert_hint_multi(iterator(hint), v);
}
iterator insert(const_iterator hint,
value_type &&v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return this->tree_.insert_hint_multi(iterator(hint), std::move(v));
}
template <typename InputIterator>
void insert(InputIterator b, InputIterator e) {
this->tree_.insert_iterator_multi(b, e);
}
void insert(std::initializer_list<init_type> init) {
this->tree_.insert_iterator_multi(init.begin(), init.end());
}
template <typename... Args>
iterator emplace(Args &&...args) ABSL_ATTRIBUTE_LIFETIME_BOUND {
// Use a node handle to manage a temp slot.
auto node = CommonAccess::Construct<node_type>(this->get_allocator(),
std::forward<Args>(args)...);
return this->tree_.insert_multi(CommonAccess::GetSlot(node));
}
template <typename... Args>
iterator emplace_hint(const_iterator hint,
Args &&...args) ABSL_ATTRIBUTE_LIFETIME_BOUND {
// Use a node handle to manage a temp slot.
auto node = CommonAccess::Construct<node_type>(this->get_allocator(),
std::forward<Args>(args)...);
return this->tree_.insert_hint_multi(iterator(hint),
CommonAccess::GetSlot(node));
}
iterator insert(node_type &&node) ABSL_ATTRIBUTE_LIFETIME_BOUND {
if (!node) return this->end();
iterator res =
this->tree_.insert_multi(params_type::key(CommonAccess::GetSlot(node)),
CommonAccess::GetSlot(node));
CommonAccess::Destroy(&node);
return res;
}
iterator insert(const_iterator hint,
node_type &&node) ABSL_ATTRIBUTE_LIFETIME_BOUND {
if (!node) return this->end();
iterator res = this->tree_.insert_hint_multi(
iterator(hint),
std::move(params_type::element(CommonAccess::GetSlot(node))));
CommonAccess::Destroy(&node);
return res;
}
// Node extraction routines.
template <typename K = key_type>
node_type extract(const key_arg<K> &key) {
const std::pair<iterator, bool> lower_and_equal =
this->tree_.lower_bound_equal(key);
return lower_and_equal.second ? extract(lower_and_equal.first)
: node_type();
}
using super_type::extract;
// Merge routines.
// Moves all elements from `src` into `this`.
template <
typename T,
typename absl::enable_if_t<
absl::conjunction<
std::is_same<value_type, typename T::value_type>,
std::is_same<allocator_type, typename T::allocator_type>,
std::is_same<typename params_type::is_map_container,
typename T::params_type::is_map_container>>::value,
int> = 0>
void merge(btree_container<T> &src) { // NOLINT
for (auto src_it = src.begin(), end = src.end(); src_it != end; ++src_it) {
insert(std::move(params_type::element(src_it.slot())));
}
src.clear();
}
template <
typename T,
typename absl::enable_if_t<
absl::conjunction<
std::is_same<value_type, typename T::value_type>,
std::is_same<allocator_type, typename T::allocator_type>,
std::is_same<typename params_type::is_map_container,
typename T::params_type::is_map_container>>::value,
int> = 0>
void merge(btree_container<T> &&src) {
merge(src);
}
};
// A base class for btree_multimap.
template <typename Tree>
class btree_multimap_container : public btree_multiset_container<Tree> {
using super_type = btree_multiset_container<Tree>;
using params_type = typename Tree::params_type;
friend class BtreeNodePeer;
public:
using mapped_type = typename params_type::mapped_type;
// Inherit constructors.
using super_type::super_type;
btree_multimap_container() {}
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_BTREE_CONTAINER_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_COMMON_H_
#define ABSL_CONTAINER_INTERNAL_COMMON_H_
#include <cassert>
#include <type_traits>
#include "absl/meta/type_traits.h"
#include "absl/types/optional.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class, class = void>
struct IsTransparent : std::false_type {};
template <class T>
struct IsTransparent<T, absl::void_t<typename T::is_transparent>>
: std::true_type {};
template <bool is_transparent>
struct KeyArg {
// Transparent. Forward `K`.
template <typename K, typename key_type>
using type = K;
};
template <>
struct KeyArg<false> {
// Not transparent. Always use `key_type`.
template <typename K, typename key_type>
using type = key_type;
};
// The node_handle concept from C++17.
// We specialize node_handle for sets and maps. node_handle_base holds the
// common API of both.
template <typename PolicyTraits, typename Alloc>
class node_handle_base {
protected:
using slot_type = typename PolicyTraits::slot_type;
public:
using allocator_type = Alloc;
constexpr node_handle_base() = default;
node_handle_base(node_handle_base&& other) noexcept {
*this = std::move(other);
}
~node_handle_base() { destroy(); }
node_handle_base& operator=(node_handle_base&& other) noexcept {
destroy();
if (!other.empty()) {
alloc_ = other.alloc_;
PolicyTraits::transfer(alloc(), slot(), other.slot());
other.reset();
}
return *this;
}
bool empty() const noexcept { return !alloc_; }
explicit operator bool() const noexcept { return !empty(); }
allocator_type get_allocator() const { return *alloc_; }
protected:
friend struct CommonAccess;
struct transfer_tag_t {};
node_handle_base(transfer_tag_t, const allocator_type& a, slot_type* s)
: alloc_(a) {
PolicyTraits::transfer(alloc(), slot(), s);
}
struct construct_tag_t {};
template <typename... Args>
node_handle_base(construct_tag_t, const allocator_type& a, Args&&... args)
: alloc_(a) {
PolicyTraits::construct(alloc(), slot(), std::forward<Args>(args)...);
}
void destroy() {
if (!empty()) {
PolicyTraits::destroy(alloc(), slot());
reset();
}
}
void reset() {
assert(alloc_.has_value());
alloc_ = absl::nullopt;
}
slot_type* slot() const {
assert(!empty());
return reinterpret_cast<slot_type*>(std::addressof(slot_space_));
}
allocator_type* alloc() { return std::addressof(*alloc_); }
private:
absl::optional<allocator_type> alloc_ = {};
alignas(slot_type) mutable unsigned char slot_space_[sizeof(slot_type)] = {};
};
// For sets.
template <typename Policy, typename PolicyTraits, typename Alloc,
typename = void>
class node_handle : public node_handle_base<PolicyTraits, Alloc> {
using Base = node_handle_base<PolicyTraits, Alloc>;
public:
using value_type = typename PolicyTraits::value_type;
constexpr node_handle() {}
value_type& value() const { return PolicyTraits::element(this->slot()); }
private:
friend struct CommonAccess;
using Base::Base;
};
// For maps.
template <typename Policy, typename PolicyTraits, typename Alloc>
class node_handle<Policy, PolicyTraits, Alloc,
absl::void_t<typename Policy::mapped_type>>
: public node_handle_base<PolicyTraits, Alloc> {
using Base = node_handle_base<PolicyTraits, Alloc>;
using slot_type = typename PolicyTraits::slot_type;
public:
using key_type = typename Policy::key_type;
using mapped_type = typename Policy::mapped_type;
constexpr node_handle() {}
// When C++17 is available, we can use std::launder to provide mutable
// access to the key. Otherwise, we provide const access.
auto key() const
-> decltype(PolicyTraits::mutable_key(std::declval<slot_type*>())) {
return PolicyTraits::mutable_key(this->slot());
}
mapped_type& mapped() const {
return PolicyTraits::value(&PolicyTraits::element(this->slot()));
}
private:
friend struct CommonAccess;
using Base::Base;
};
// Provide access to non-public node-handle functions.
struct CommonAccess {
template <typename Node>
static auto GetSlot(const Node& node) -> decltype(node.slot()) {
return node.slot();
}
template <typename Node>
static void Destroy(Node* node) {
node->destroy();
}
template <typename Node>
static void Reset(Node* node) {
node->reset();
}
template <typename T, typename... Args>
static T Transfer(Args&&... args) {
return T(typename T::transfer_tag_t{}, std::forward<Args>(args)...);
}
template <typename T, typename... Args>
static T Construct(Args&&... args) {
return T(typename T::construct_tag_t{}, std::forward<Args>(args)...);
}
};
// Implement the insert_return_type<> concept of C++17.
template <class Iterator, class NodeType>
struct InsertReturnType {
Iterator position;
bool inserted;
NodeType node;
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_COMMON_H_

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// Copyright 2022 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_COMMON_POLICY_TRAITS_H_
#define ABSL_CONTAINER_INTERNAL_COMMON_POLICY_TRAITS_H_
#include <cstddef>
#include <cstring>
#include <memory>
#include <new>
#include <type_traits>
#include <utility>
#include "absl/meta/type_traits.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// Defines how slots are initialized/destroyed/moved.
template <class Policy, class = void>
struct common_policy_traits {
// The actual object stored in the container.
using slot_type = typename Policy::slot_type;
using reference = decltype(Policy::element(std::declval<slot_type*>()));
using value_type = typename std::remove_reference<reference>::type;
// PRECONDITION: `slot` is UNINITIALIZED
// POSTCONDITION: `slot` is INITIALIZED
template <class Alloc, class... Args>
static void construct(Alloc* alloc, slot_type* slot, Args&&... args) {
Policy::construct(alloc, slot, std::forward<Args>(args)...);
}
// PRECONDITION: `slot` is INITIALIZED
// POSTCONDITION: `slot` is UNINITIALIZED
template <class Alloc>
static void destroy(Alloc* alloc, slot_type* slot) {
Policy::destroy(alloc, slot);
}
// Transfers the `old_slot` to `new_slot`. Any memory allocated by the
// allocator inside `old_slot` to `new_slot` can be transferred.
//
// OPTIONAL: defaults to:
//
// clone(new_slot, std::move(*old_slot));
// destroy(old_slot);
//
// PRECONDITION: `new_slot` is UNINITIALIZED and `old_slot` is INITIALIZED
// POSTCONDITION: `new_slot` is INITIALIZED and `old_slot` is
// UNINITIALIZED
template <class Alloc>
static void transfer(Alloc* alloc, slot_type* new_slot, slot_type* old_slot) {
transfer_impl(alloc, new_slot, old_slot, Rank0{});
}
// PRECONDITION: `slot` is INITIALIZED
// POSTCONDITION: `slot` is INITIALIZED
// Note: we use remove_const_t so that the two overloads have different args
// in the case of sets with explicitly const value_types.
template <class P = Policy>
static auto element(absl::remove_const_t<slot_type>* slot)
-> decltype(P::element(slot)) {
return P::element(slot);
}
template <class P = Policy>
static auto element(const slot_type* slot) -> decltype(P::element(slot)) {
return P::element(slot);
}
static constexpr bool transfer_uses_memcpy() {
return std::is_same<decltype(transfer_impl<std::allocator<char>>(
nullptr, nullptr, nullptr, Rank0{})),
std::true_type>::value;
}
private:
// To rank the overloads below for overload resolution. Rank0 is preferred.
struct Rank2 {};
struct Rank1 : Rank2 {};
struct Rank0 : Rank1 {};
// Use auto -> decltype as an enabler.
// P::transfer returns std::true_type if transfer uses memcpy (e.g. in
// node_slot_policy).
template <class Alloc, class P = Policy>
static auto transfer_impl(Alloc* alloc, slot_type* new_slot,
slot_type* old_slot, Rank0)
-> decltype(P::transfer(alloc, new_slot, old_slot)) {
return P::transfer(alloc, new_slot, old_slot);
}
#if defined(__cpp_lib_launder) && __cpp_lib_launder >= 201606
// This overload returns true_type for the trait below.
// The conditional_t is to make the enabler type dependent.
template <class Alloc,
typename = std::enable_if_t<absl::is_trivially_relocatable<
std::conditional_t<false, Alloc, value_type>>::value>>
static std::true_type transfer_impl(Alloc*, slot_type* new_slot,
slot_type* old_slot, Rank1) {
// TODO(b/247130232): remove casts after fixing warnings.
// TODO(b/251814870): remove casts after fixing warnings.
std::memcpy(
static_cast<void*>(std::launder(
const_cast<std::remove_const_t<value_type>*>(&element(new_slot)))),
static_cast<const void*>(&element(old_slot)), sizeof(value_type));
return {};
}
#endif
template <class Alloc>
static void transfer_impl(Alloc* alloc, slot_type* new_slot,
slot_type* old_slot, Rank2) {
construct(alloc, new_slot, std::move(element(old_slot)));
destroy(alloc, old_slot);
}
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_COMMON_POLICY_TRAITS_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Helper class to perform the Empty Base Optimization.
// Ts can contain classes and non-classes, empty or not. For the ones that
// are empty classes, we perform the optimization. If all types in Ts are empty
// classes, then CompressedTuple<Ts...> is itself an empty class.
//
// To access the members, use member get<N>() function.
//
// Eg:
// absl::container_internal::CompressedTuple<int, T1, T2, T3> value(7, t1, t2,
// t3);
// assert(value.get<0>() == 7);
// T1& t1 = value.get<1>();
// const T2& t2 = value.get<2>();
// ...
//
// https://en.cppreference.com/w/cpp/language/ebo
#ifndef ABSL_CONTAINER_INTERNAL_COMPRESSED_TUPLE_H_
#define ABSL_CONTAINER_INTERNAL_COMPRESSED_TUPLE_H_
#include <initializer_list>
#include <tuple>
#include <type_traits>
#include <utility>
#include "absl/utility/utility.h"
#if defined(_MSC_VER) && !defined(__NVCC__)
// We need to mark these classes with this declspec to ensure that
// CompressedTuple happens.
#define ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC __declspec(empty_bases)
#else
#define ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC
#endif
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <typename... Ts>
class CompressedTuple;
namespace internal_compressed_tuple {
template <typename D, size_t I>
struct Elem;
template <typename... B, size_t I>
struct Elem<CompressedTuple<B...>, I>
: std::tuple_element<I, std::tuple<B...>> {};
template <typename D, size_t I>
using ElemT = typename Elem<D, I>::type;
// We can't use EBCO on other CompressedTuples because that would mean that we
// derive from multiple Storage<> instantiations with the same I parameter,
// and potentially from multiple identical Storage<> instantiations. So anytime
// we use type inheritance rather than encapsulation, we mark
// CompressedTupleImpl, to make this easy to detect.
struct uses_inheritance {};
template <typename T>
constexpr bool ShouldUseBase() {
return std::is_class<T>::value && std::is_empty<T>::value &&
!std::is_final<T>::value &&
!std::is_base_of<uses_inheritance, T>::value;
}
// The storage class provides two specializations:
// - For empty classes, it stores T as a base class.
// - For everything else, it stores T as a member.
template <typename T, size_t I, bool UseBase = ShouldUseBase<T>()>
struct Storage {
T value;
constexpr Storage() = default;
template <typename V>
explicit constexpr Storage(absl::in_place_t, V&& v)
: value(absl::forward<V>(v)) {}
constexpr const T& get() const& { return value; }
T& get() & { return value; }
constexpr const T&& get() const&& { return absl::move(*this).value; }
T&& get() && { return std::move(*this).value; }
};
template <typename T, size_t I>
struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC Storage<T, I, true> : T {
constexpr Storage() = default;
template <typename V>
explicit constexpr Storage(absl::in_place_t, V&& v)
: T(absl::forward<V>(v)) {}
constexpr const T& get() const& { return *this; }
T& get() & { return *this; }
constexpr const T&& get() const&& { return absl::move(*this); }
T&& get() && { return std::move(*this); }
};
template <typename D, typename I, bool ShouldAnyUseBase>
struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTupleImpl;
template <typename... Ts, size_t... I, bool ShouldAnyUseBase>
struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTupleImpl<
CompressedTuple<Ts...>, absl::index_sequence<I...>, ShouldAnyUseBase>
// We use the dummy identity function through std::integral_constant to
// convince MSVC of accepting and expanding I in that context. Without it
// you would get:
// error C3548: 'I': parameter pack cannot be used in this context
: uses_inheritance,
Storage<Ts, std::integral_constant<size_t, I>::value>... {
constexpr CompressedTupleImpl() = default;
template <typename... Vs>
explicit constexpr CompressedTupleImpl(absl::in_place_t, Vs&&... args)
: Storage<Ts, I>(absl::in_place, absl::forward<Vs>(args))... {}
friend CompressedTuple<Ts...>;
};
template <typename... Ts, size_t... I>
struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTupleImpl<
CompressedTuple<Ts...>, absl::index_sequence<I...>, false>
// We use the dummy identity function as above...
: Storage<Ts, std::integral_constant<size_t, I>::value, false>... {
constexpr CompressedTupleImpl() = default;
template <typename... Vs>
explicit constexpr CompressedTupleImpl(absl::in_place_t, Vs&&... args)
: Storage<Ts, I, false>(absl::in_place, absl::forward<Vs>(args))... {}
friend CompressedTuple<Ts...>;
};
std::false_type Or(std::initializer_list<std::false_type>);
std::true_type Or(std::initializer_list<bool>);
// MSVC requires this to be done separately rather than within the declaration
// of CompressedTuple below.
template <typename... Ts>
constexpr bool ShouldAnyUseBase() {
return decltype(
Or({std::integral_constant<bool, ShouldUseBase<Ts>()>()...})){};
}
template <typename T, typename V>
using TupleElementMoveConstructible =
typename std::conditional<std::is_reference<T>::value,
std::is_convertible<V, T>,
std::is_constructible<T, V&&>>::type;
template <bool SizeMatches, class T, class... Vs>
struct TupleMoveConstructible : std::false_type {};
template <class... Ts, class... Vs>
struct TupleMoveConstructible<true, CompressedTuple<Ts...>, Vs...>
: std::integral_constant<
bool, absl::conjunction<
TupleElementMoveConstructible<Ts, Vs&&>...>::value> {};
template <typename T>
struct compressed_tuple_size;
template <typename... Es>
struct compressed_tuple_size<CompressedTuple<Es...>>
: public std::integral_constant<std::size_t, sizeof...(Es)> {};
template <class T, class... Vs>
struct TupleItemsMoveConstructible
: std::integral_constant<
bool, TupleMoveConstructible<compressed_tuple_size<T>::value ==
sizeof...(Vs),
T, Vs...>::value> {};
} // namespace internal_compressed_tuple
// Helper class to perform the Empty Base Class Optimization.
// Ts can contain classes and non-classes, empty or not. For the ones that
// are empty classes, we perform the CompressedTuple. If all types in Ts are
// empty classes, then CompressedTuple<Ts...> is itself an empty class. (This
// does not apply when one or more of those empty classes is itself an empty
// CompressedTuple.)
//
// To access the members, use member .get<N>() function.
//
// Eg:
// absl::container_internal::CompressedTuple<int, T1, T2, T3> value(7, t1, t2,
// t3);
// assert(value.get<0>() == 7);
// T1& t1 = value.get<1>();
// const T2& t2 = value.get<2>();
// ...
//
// https://en.cppreference.com/w/cpp/language/ebo
template <typename... Ts>
class ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTuple
: private internal_compressed_tuple::CompressedTupleImpl<
CompressedTuple<Ts...>, absl::index_sequence_for<Ts...>,
internal_compressed_tuple::ShouldAnyUseBase<Ts...>()> {
private:
template <int I>
using ElemT = internal_compressed_tuple::ElemT<CompressedTuple, I>;
template <int I>
using StorageT = internal_compressed_tuple::Storage<ElemT<I>, I>;
public:
// There seems to be a bug in MSVC dealing in which using '=default' here will
// cause the compiler to ignore the body of other constructors. The work-
// around is to explicitly implement the default constructor.
#if defined(_MSC_VER)
constexpr CompressedTuple() : CompressedTuple::CompressedTupleImpl() {}
#else
constexpr CompressedTuple() = default;
#endif
explicit constexpr CompressedTuple(const Ts&... base)
: CompressedTuple::CompressedTupleImpl(absl::in_place, base...) {}
template <typename First, typename... Vs,
absl::enable_if_t<
absl::conjunction<
// Ensure we are not hiding default copy/move constructors.
absl::negation<std::is_same<void(CompressedTuple),
void(absl::decay_t<First>)>>,
internal_compressed_tuple::TupleItemsMoveConstructible<
CompressedTuple<Ts...>, First, Vs...>>::value,
bool> = true>
explicit constexpr CompressedTuple(First&& first, Vs&&... base)
: CompressedTuple::CompressedTupleImpl(absl::in_place,
absl::forward<First>(first),
absl::forward<Vs>(base)...) {}
template <int I>
ElemT<I>& get() & {
return StorageT<I>::get();
}
template <int I>
constexpr const ElemT<I>& get() const& {
return StorageT<I>::get();
}
template <int I>
ElemT<I>&& get() && {
return std::move(*this).StorageT<I>::get();
}
template <int I>
constexpr const ElemT<I>&& get() const&& {
return absl::move(*this).StorageT<I>::get();
}
};
// Explicit specialization for a zero-element tuple
// (needed to avoid ambiguous overloads for the default constructor).
template <>
class ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTuple<> {};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#undef ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC
#endif // ABSL_CONTAINER_INTERNAL_COMPRESSED_TUPLE_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_CONTAINER_MEMORY_H_
#define ABSL_CONTAINER_INTERNAL_CONTAINER_MEMORY_H_
#include <cassert>
#include <cstddef>
#include <cstring>
#include <memory>
#include <new>
#include <tuple>
#include <type_traits>
#include <utility>
#include "absl/base/config.h"
#include "absl/memory/memory.h"
#include "absl/meta/type_traits.h"
#include "absl/utility/utility.h"
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
#include <sanitizer/asan_interface.h>
#endif
#ifdef ABSL_HAVE_MEMORY_SANITIZER
#include <sanitizer/msan_interface.h>
#endif
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <size_t Alignment>
struct alignas(Alignment) AlignedType {};
// Allocates at least n bytes aligned to the specified alignment.
// Alignment must be a power of 2. It must be positive.
//
// Note that many allocators don't honor alignment requirements above certain
// threshold (usually either alignof(std::max_align_t) or alignof(void*)).
// Allocate() doesn't apply alignment corrections. If the underlying allocator
// returns insufficiently alignment pointer, that's what you are going to get.
template <size_t Alignment, class Alloc>
void* Allocate(Alloc* alloc, size_t n) {
static_assert(Alignment > 0, "");
assert(n && "n must be positive");
using M = AlignedType<Alignment>;
using A = typename absl::allocator_traits<Alloc>::template rebind_alloc<M>;
using AT = typename absl::allocator_traits<Alloc>::template rebind_traits<M>;
// On macOS, "mem_alloc" is a #define with one argument defined in
// rpc/types.h, so we can't name the variable "mem_alloc" and initialize it
// with the "foo(bar)" syntax.
A my_mem_alloc(*alloc);
void* p = AT::allocate(my_mem_alloc, (n + sizeof(M) - 1) / sizeof(M));
assert(reinterpret_cast<uintptr_t>(p) % Alignment == 0 &&
"allocator does not respect alignment");
return p;
}
// The pointer must have been previously obtained by calling
// Allocate<Alignment>(alloc, n).
template <size_t Alignment, class Alloc>
void Deallocate(Alloc* alloc, void* p, size_t n) {
static_assert(Alignment > 0, "");
assert(n && "n must be positive");
using M = AlignedType<Alignment>;
using A = typename absl::allocator_traits<Alloc>::template rebind_alloc<M>;
using AT = typename absl::allocator_traits<Alloc>::template rebind_traits<M>;
// On macOS, "mem_alloc" is a #define with one argument defined in
// rpc/types.h, so we can't name the variable "mem_alloc" and initialize it
// with the "foo(bar)" syntax.
A my_mem_alloc(*alloc);
AT::deallocate(my_mem_alloc, static_cast<M*>(p),
(n + sizeof(M) - 1) / sizeof(M));
}
namespace memory_internal {
// Constructs T into uninitialized storage pointed by `ptr` using the args
// specified in the tuple.
template <class Alloc, class T, class Tuple, size_t... I>
void ConstructFromTupleImpl(Alloc* alloc, T* ptr, Tuple&& t,
absl::index_sequence<I...>) {
absl::allocator_traits<Alloc>::construct(
*alloc, ptr, std::get<I>(std::forward<Tuple>(t))...);
}
template <class T, class F>
struct WithConstructedImplF {
template <class... Args>
decltype(std::declval<F>()(std::declval<T>())) operator()(
Args&&... args) const {
return std::forward<F>(f)(T(std::forward<Args>(args)...));
}
F&& f;
};
template <class T, class Tuple, size_t... Is, class F>
decltype(std::declval<F>()(std::declval<T>())) WithConstructedImpl(
Tuple&& t, absl::index_sequence<Is...>, F&& f) {
return WithConstructedImplF<T, F>{std::forward<F>(f)}(
std::get<Is>(std::forward<Tuple>(t))...);
}
template <class T, size_t... Is>
auto TupleRefImpl(T&& t, absl::index_sequence<Is...>)
-> decltype(std::forward_as_tuple(std::get<Is>(std::forward<T>(t))...)) {
return std::forward_as_tuple(std::get<Is>(std::forward<T>(t))...);
}
// Returns a tuple of references to the elements of the input tuple. T must be a
// tuple.
template <class T>
auto TupleRef(T&& t) -> decltype(TupleRefImpl(
std::forward<T>(t),
absl::make_index_sequence<
std::tuple_size<typename std::decay<T>::type>::value>())) {
return TupleRefImpl(
std::forward<T>(t),
absl::make_index_sequence<
std::tuple_size<typename std::decay<T>::type>::value>());
}
template <class F, class K, class V>
decltype(std::declval<F>()(std::declval<const K&>(), std::piecewise_construct,
std::declval<std::tuple<K>>(), std::declval<V>()))
DecomposePairImpl(F&& f, std::pair<std::tuple<K>, V> p) {
const auto& key = std::get<0>(p.first);
return std::forward<F>(f)(key, std::piecewise_construct, std::move(p.first),
std::move(p.second));
}
} // namespace memory_internal
// Constructs T into uninitialized storage pointed by `ptr` using the args
// specified in the tuple.
template <class Alloc, class T, class Tuple>
void ConstructFromTuple(Alloc* alloc, T* ptr, Tuple&& t) {
memory_internal::ConstructFromTupleImpl(
alloc, ptr, std::forward<Tuple>(t),
absl::make_index_sequence<
std::tuple_size<typename std::decay<Tuple>::type>::value>());
}
// Constructs T using the args specified in the tuple and calls F with the
// constructed value.
template <class T, class Tuple, class F>
decltype(std::declval<F>()(std::declval<T>())) WithConstructed(Tuple&& t,
F&& f) {
return memory_internal::WithConstructedImpl<T>(
std::forward<Tuple>(t),
absl::make_index_sequence<
std::tuple_size<typename std::decay<Tuple>::type>::value>(),
std::forward<F>(f));
}
// Given arguments of an std::pair's constructor, PairArgs() returns a pair of
// tuples with references to the passed arguments. The tuples contain
// constructor arguments for the first and the second elements of the pair.
//
// The following two snippets are equivalent.
//
// 1. std::pair<F, S> p(args...);
//
// 2. auto a = PairArgs(args...);
// std::pair<F, S> p(std::piecewise_construct,
// std::move(a.first), std::move(a.second));
inline std::pair<std::tuple<>, std::tuple<>> PairArgs() { return {}; }
template <class F, class S>
std::pair<std::tuple<F&&>, std::tuple<S&&>> PairArgs(F&& f, S&& s) {
return {std::piecewise_construct, std::forward_as_tuple(std::forward<F>(f)),
std::forward_as_tuple(std::forward<S>(s))};
}
template <class F, class S>
std::pair<std::tuple<const F&>, std::tuple<const S&>> PairArgs(
const std::pair<F, S>& p) {
return PairArgs(p.first, p.second);
}
template <class F, class S>
std::pair<std::tuple<F&&>, std::tuple<S&&>> PairArgs(std::pair<F, S>&& p) {
return PairArgs(std::forward<F>(p.first), std::forward<S>(p.second));
}
template <class F, class S>
auto PairArgs(std::piecewise_construct_t, F&& f, S&& s)
-> decltype(std::make_pair(memory_internal::TupleRef(std::forward<F>(f)),
memory_internal::TupleRef(std::forward<S>(s)))) {
return std::make_pair(memory_internal::TupleRef(std::forward<F>(f)),
memory_internal::TupleRef(std::forward<S>(s)));
}
// A helper function for implementing apply() in map policies.
template <class F, class... Args>
auto DecomposePair(F&& f, Args&&... args)
-> decltype(memory_internal::DecomposePairImpl(
std::forward<F>(f), PairArgs(std::forward<Args>(args)...))) {
return memory_internal::DecomposePairImpl(
std::forward<F>(f), PairArgs(std::forward<Args>(args)...));
}
// A helper function for implementing apply() in set policies.
template <class F, class Arg>
decltype(std::declval<F>()(std::declval<const Arg&>(), std::declval<Arg>()))
DecomposeValue(F&& f, Arg&& arg) {
const auto& key = arg;
return std::forward<F>(f)(key, std::forward<Arg>(arg));
}
// Helper functions for asan and msan.
inline void SanitizerPoisonMemoryRegion(const void* m, size_t s) {
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
ASAN_POISON_MEMORY_REGION(m, s);
#endif
#ifdef ABSL_HAVE_MEMORY_SANITIZER
__msan_poison(m, s);
#endif
(void)m;
(void)s;
}
inline void SanitizerUnpoisonMemoryRegion(const void* m, size_t s) {
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
ASAN_UNPOISON_MEMORY_REGION(m, s);
#endif
#ifdef ABSL_HAVE_MEMORY_SANITIZER
__msan_unpoison(m, s);
#endif
(void)m;
(void)s;
}
template <typename T>
inline void SanitizerPoisonObject(const T* object) {
SanitizerPoisonMemoryRegion(object, sizeof(T));
}
template <typename T>
inline void SanitizerUnpoisonObject(const T* object) {
SanitizerUnpoisonMemoryRegion(object, sizeof(T));
}
namespace memory_internal {
// If Pair is a standard-layout type, OffsetOf<Pair>::kFirst and
// OffsetOf<Pair>::kSecond are equivalent to offsetof(Pair, first) and
// offsetof(Pair, second) respectively. Otherwise they are -1.
//
// The purpose of OffsetOf is to avoid calling offsetof() on non-standard-layout
// type, which is non-portable.
template <class Pair, class = std::true_type>
struct OffsetOf {
static constexpr size_t kFirst = static_cast<size_t>(-1);
static constexpr size_t kSecond = static_cast<size_t>(-1);
};
template <class Pair>
struct OffsetOf<Pair, typename std::is_standard_layout<Pair>::type> {
static constexpr size_t kFirst = offsetof(Pair, first);
static constexpr size_t kSecond = offsetof(Pair, second);
};
template <class K, class V>
struct IsLayoutCompatible {
private:
struct Pair {
K first;
V second;
};
// Is P layout-compatible with Pair?
template <class P>
static constexpr bool LayoutCompatible() {
return std::is_standard_layout<P>() && sizeof(P) == sizeof(Pair) &&
alignof(P) == alignof(Pair) &&
memory_internal::OffsetOf<P>::kFirst ==
memory_internal::OffsetOf<Pair>::kFirst &&
memory_internal::OffsetOf<P>::kSecond ==
memory_internal::OffsetOf<Pair>::kSecond;
}
public:
// Whether pair<const K, V> and pair<K, V> are layout-compatible. If they are,
// then it is safe to store them in a union and read from either.
static constexpr bool value = std::is_standard_layout<K>() &&
std::is_standard_layout<Pair>() &&
memory_internal::OffsetOf<Pair>::kFirst == 0 &&
LayoutCompatible<std::pair<K, V>>() &&
LayoutCompatible<std::pair<const K, V>>();
};
} // namespace memory_internal
// The internal storage type for key-value containers like flat_hash_map.
//
// It is convenient for the value_type of a flat_hash_map<K, V> to be
// pair<const K, V>; the "const K" prevents accidental modification of the key
// when dealing with the reference returned from find() and similar methods.
// However, this creates other problems; we want to be able to emplace(K, V)
// efficiently with move operations, and similarly be able to move a
// pair<K, V> in insert().
//
// The solution is this union, which aliases the const and non-const versions
// of the pair. This also allows flat_hash_map<const K, V> to work, even though
// that has the same efficiency issues with move in emplace() and insert() -
// but people do it anyway.
//
// If kMutableKeys is false, only the value member can be accessed.
//
// If kMutableKeys is true, key can be accessed through all slots while value
// and mutable_value must be accessed only via INITIALIZED slots. Slots are
// created and destroyed via mutable_value so that the key can be moved later.
//
// Accessing one of the union fields while the other is active is safe as
// long as they are layout-compatible, which is guaranteed by the definition of
// kMutableKeys. For C++11, the relevant section of the standard is
// https://timsong-cpp.github.io/cppwp/n3337/class.mem#19 (9.2.19)
template <class K, class V>
union map_slot_type {
map_slot_type() {}
~map_slot_type() = delete;
using value_type = std::pair<const K, V>;
using mutable_value_type =
std::pair<absl::remove_const_t<K>, absl::remove_const_t<V>>;
value_type value;
mutable_value_type mutable_value;
absl::remove_const_t<K> key;
};
template <class K, class V>
struct map_slot_policy {
using slot_type = map_slot_type<K, V>;
using value_type = std::pair<const K, V>;
using mutable_value_type =
std::pair<absl::remove_const_t<K>, absl::remove_const_t<V>>;
private:
static void emplace(slot_type* slot) {
// The construction of union doesn't do anything at runtime but it allows us
// to access its members without violating aliasing rules.
new (slot) slot_type;
}
// If pair<const K, V> and pair<K, V> are layout-compatible, we can accept one
// or the other via slot_type. We are also free to access the key via
// slot_type::key in this case.
using kMutableKeys = memory_internal::IsLayoutCompatible<K, V>;
public:
static value_type& element(slot_type* slot) { return slot->value; }
static const value_type& element(const slot_type* slot) {
return slot->value;
}
// When C++17 is available, we can use std::launder to provide mutable
// access to the key for use in node handle.
#if defined(__cpp_lib_launder) && __cpp_lib_launder >= 201606
static K& mutable_key(slot_type* slot) {
// Still check for kMutableKeys so that we can avoid calling std::launder
// unless necessary because it can interfere with optimizations.
return kMutableKeys::value ? slot->key
: *std::launder(const_cast<K*>(
std::addressof(slot->value.first)));
}
#else // !(defined(__cpp_lib_launder) && __cpp_lib_launder >= 201606)
static const K& mutable_key(slot_type* slot) { return key(slot); }
#endif
static const K& key(const slot_type* slot) {
return kMutableKeys::value ? slot->key : slot->value.first;
}
template <class Allocator, class... Args>
static void construct(Allocator* alloc, slot_type* slot, Args&&... args) {
emplace(slot);
if (kMutableKeys::value) {
absl::allocator_traits<Allocator>::construct(*alloc, &slot->mutable_value,
std::forward<Args>(args)...);
} else {
absl::allocator_traits<Allocator>::construct(*alloc, &slot->value,
std::forward<Args>(args)...);
}
}
// Construct this slot by moving from another slot.
template <class Allocator>
static void construct(Allocator* alloc, slot_type* slot, slot_type* other) {
emplace(slot);
if (kMutableKeys::value) {
absl::allocator_traits<Allocator>::construct(
*alloc, &slot->mutable_value, std::move(other->mutable_value));
} else {
absl::allocator_traits<Allocator>::construct(*alloc, &slot->value,
std::move(other->value));
}
}
// Construct this slot by copying from another slot.
template <class Allocator>
static void construct(Allocator* alloc, slot_type* slot,
const slot_type* other) {
emplace(slot);
absl::allocator_traits<Allocator>::construct(*alloc, &slot->value,
other->value);
}
template <class Allocator>
static void destroy(Allocator* alloc, slot_type* slot) {
if (kMutableKeys::value) {
absl::allocator_traits<Allocator>::destroy(*alloc, &slot->mutable_value);
} else {
absl::allocator_traits<Allocator>::destroy(*alloc, &slot->value);
}
}
template <class Allocator>
static auto transfer(Allocator* alloc, slot_type* new_slot,
slot_type* old_slot) {
auto is_relocatable =
typename absl::is_trivially_relocatable<value_type>::type();
emplace(new_slot);
#if defined(__cpp_lib_launder) && __cpp_lib_launder >= 201606
if (is_relocatable) {
// TODO(b/247130232,b/251814870): remove casts after fixing warnings.
std::memcpy(static_cast<void*>(std::launder(&new_slot->value)),
static_cast<const void*>(&old_slot->value),
sizeof(value_type));
return is_relocatable;
}
#endif
if (kMutableKeys::value) {
absl::allocator_traits<Allocator>::construct(
*alloc, &new_slot->mutable_value, std::move(old_slot->mutable_value));
} else {
absl::allocator_traits<Allocator>::construct(*alloc, &new_slot->value,
std::move(old_slot->value));
}
destroy(alloc, old_slot);
return is_relocatable;
}
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_CONTAINER_MEMORY_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Define the default Hash and Eq functions for SwissTable containers.
//
// std::hash<T> and std::equal_to<T> are not appropriate hash and equal
// functions for SwissTable containers. There are two reasons for this.
//
// SwissTable containers are power of 2 sized containers:
//
// This means they use the lower bits of the hash value to find the slot for
// each entry. The typical hash function for integral types is the identity.
// This is a very weak hash function for SwissTable and any power of 2 sized
// hashtable implementation which will lead to excessive collisions. For
// SwissTable we use murmur3 style mixing to reduce collisions to a minimum.
//
// SwissTable containers support heterogeneous lookup:
//
// In order to make heterogeneous lookup work, hash and equal functions must be
// polymorphic. At the same time they have to satisfy the same requirements the
// C++ standard imposes on hash functions and equality operators. That is:
//
// if hash_default_eq<T>(a, b) returns true for any a and b of type T, then
// hash_default_hash<T>(a) must equal hash_default_hash<T>(b)
//
// For SwissTable containers this requirement is relaxed to allow a and b of
// any and possibly different types. Note that like the standard the hash and
// equal functions are still bound to T. This is important because some type U
// can be hashed by/tested for equality differently depending on T. A notable
// example is `const char*`. `const char*` is treated as a c-style string when
// the hash function is hash<std::string> but as a pointer when the hash
// function is hash<void*>.
//
#ifndef ABSL_CONTAINER_INTERNAL_HASH_FUNCTION_DEFAULTS_H_
#define ABSL_CONTAINER_INTERNAL_HASH_FUNCTION_DEFAULTS_H_
#include <stdint.h>
#include <cstddef>
#include <memory>
#include <string>
#include <type_traits>
#include "absl/base/config.h"
#include "absl/hash/hash.h"
#include "absl/strings/cord.h"
#include "absl/strings/string_view.h"
#ifdef ABSL_HAVE_STD_STRING_VIEW
#include <string_view>
#endif
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// The hash of an object of type T is computed by using absl::Hash.
template <class T, class E = void>
struct HashEq {
using Hash = absl::Hash<T>;
using Eq = std::equal_to<T>;
};
struct StringHash {
using is_transparent = void;
size_t operator()(absl::string_view v) const {
return absl::Hash<absl::string_view>{}(v);
}
size_t operator()(const absl::Cord& v) const {
return absl::Hash<absl::Cord>{}(v);
}
};
struct StringEq {
using is_transparent = void;
bool operator()(absl::string_view lhs, absl::string_view rhs) const {
return lhs == rhs;
}
bool operator()(const absl::Cord& lhs, const absl::Cord& rhs) const {
return lhs == rhs;
}
bool operator()(const absl::Cord& lhs, absl::string_view rhs) const {
return lhs == rhs;
}
bool operator()(absl::string_view lhs, const absl::Cord& rhs) const {
return lhs == rhs;
}
};
// Supports heterogeneous lookup for string-like elements.
struct StringHashEq {
using Hash = StringHash;
using Eq = StringEq;
};
template <>
struct HashEq<std::string> : StringHashEq {};
template <>
struct HashEq<absl::string_view> : StringHashEq {};
template <>
struct HashEq<absl::Cord> : StringHashEq {};
#ifdef ABSL_HAVE_STD_STRING_VIEW
template <typename TChar>
struct BasicStringHash {
using is_transparent = void;
size_t operator()(std::basic_string_view<TChar> v) const {
return absl::Hash<std::basic_string_view<TChar>>{}(v);
}
};
template <typename TChar>
struct BasicStringEq {
using is_transparent = void;
bool operator()(std::basic_string_view<TChar> lhs,
std::basic_string_view<TChar> rhs) const {
return lhs == rhs;
}
};
// Supports heterogeneous lookup for w/u16/u32 string + string_view + char*.
template <typename TChar>
struct BasicStringHashEq {
using Hash = BasicStringHash<TChar>;
using Eq = BasicStringEq<TChar>;
};
template <>
struct HashEq<std::wstring> : BasicStringHashEq<wchar_t> {};
template <>
struct HashEq<std::wstring_view> : BasicStringHashEq<wchar_t> {};
template <>
struct HashEq<std::u16string> : BasicStringHashEq<char16_t> {};
template <>
struct HashEq<std::u16string_view> : BasicStringHashEq<char16_t> {};
template <>
struct HashEq<std::u32string> : BasicStringHashEq<char32_t> {};
template <>
struct HashEq<std::u32string_view> : BasicStringHashEq<char32_t> {};
#endif // ABSL_HAVE_STD_STRING_VIEW
// Supports heterogeneous lookup for pointers and smart pointers.
template <class T>
struct HashEq<T*> {
struct Hash {
using is_transparent = void;
template <class U>
size_t operator()(const U& ptr) const {
return absl::Hash<const T*>{}(HashEq::ToPtr(ptr));
}
};
struct Eq {
using is_transparent = void;
template <class A, class B>
bool operator()(const A& a, const B& b) const {
return HashEq::ToPtr(a) == HashEq::ToPtr(b);
}
};
private:
static const T* ToPtr(const T* ptr) { return ptr; }
template <class U, class D>
static const T* ToPtr(const std::unique_ptr<U, D>& ptr) {
return ptr.get();
}
template <class U>
static const T* ToPtr(const std::shared_ptr<U>& ptr) {
return ptr.get();
}
};
template <class T, class D>
struct HashEq<std::unique_ptr<T, D>> : HashEq<T*> {};
template <class T>
struct HashEq<std::shared_ptr<T>> : HashEq<T*> {};
// This header's visibility is restricted. If you need to access the default
// hasher please use the container's ::hasher alias instead.
//
// Example: typename Hash = typename absl::flat_hash_map<K, V>::hasher
template <class T>
using hash_default_hash = typename container_internal::HashEq<T>::Hash;
// This header's visibility is restricted. If you need to access the default
// key equal please use the container's ::key_equal alias instead.
//
// Example: typename Eq = typename absl::flat_hash_map<K, V, Hash>::key_equal
template <class T>
using hash_default_eq = typename container_internal::HashEq<T>::Eq;
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_HASH_FUNCTION_DEFAULTS_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Generates random values for testing. Specialized only for the few types we
// care about.
#ifndef ABSL_CONTAINER_INTERNAL_HASH_GENERATOR_TESTING_H_
#define ABSL_CONTAINER_INTERNAL_HASH_GENERATOR_TESTING_H_
#include <stdint.h>
#include <algorithm>
#include <cassert>
#include <iosfwd>
#include <random>
#include <tuple>
#include <type_traits>
#include <utility>
#include <vector>
#include "absl/container/internal/hash_policy_testing.h"
#include "absl/memory/memory.h"
#include "absl/meta/type_traits.h"
#include "absl/strings/string_view.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
namespace hash_internal {
namespace generator_internal {
template <class Container, class = void>
struct IsMap : std::false_type {};
template <class Map>
struct IsMap<Map, absl::void_t<typename Map::mapped_type>> : std::true_type {};
} // namespace generator_internal
std::mt19937_64* GetSharedRng();
enum Enum {
kEnumEmpty,
kEnumDeleted,
};
enum class EnumClass : uint64_t {
kEmpty,
kDeleted,
};
inline std::ostream& operator<<(std::ostream& o, const EnumClass& ec) {
return o << static_cast<uint64_t>(ec);
}
template <class T, class E = void>
struct Generator;
template <class T>
struct Generator<T, typename std::enable_if<std::is_integral<T>::value>::type> {
T operator()() const {
std::uniform_int_distribution<T> dist;
return dist(*GetSharedRng());
}
};
template <>
struct Generator<Enum> {
Enum operator()() const {
std::uniform_int_distribution<typename std::underlying_type<Enum>::type>
dist;
while (true) {
auto variate = dist(*GetSharedRng());
if (variate != kEnumEmpty && variate != kEnumDeleted)
return static_cast<Enum>(variate);
}
}
};
template <>
struct Generator<EnumClass> {
EnumClass operator()() const {
std::uniform_int_distribution<
typename std::underlying_type<EnumClass>::type>
dist;
while (true) {
EnumClass variate = static_cast<EnumClass>(dist(*GetSharedRng()));
if (variate != EnumClass::kEmpty && variate != EnumClass::kDeleted)
return static_cast<EnumClass>(variate);
}
}
};
template <>
struct Generator<std::string> {
std::string operator()() const;
};
template <>
struct Generator<absl::string_view> {
absl::string_view operator()() const;
};
template <>
struct Generator<NonStandardLayout> {
NonStandardLayout operator()() const {
return NonStandardLayout(Generator<std::string>()());
}
};
template <class K, class V>
struct Generator<std::pair<K, V>> {
std::pair<K, V> operator()() const {
return std::pair<K, V>(Generator<typename std::decay<K>::type>()(),
Generator<typename std::decay<V>::type>()());
}
};
template <class... Ts>
struct Generator<std::tuple<Ts...>> {
std::tuple<Ts...> operator()() const {
return std::tuple<Ts...>(Generator<typename std::decay<Ts>::type>()()...);
}
};
template <class T>
struct Generator<std::unique_ptr<T>> {
std::unique_ptr<T> operator()() const {
return absl::make_unique<T>(Generator<T>()());
}
};
template <class U>
struct Generator<U, absl::void_t<decltype(std::declval<U&>().key()),
decltype(std::declval<U&>().value())>>
: Generator<std::pair<
typename std::decay<decltype(std::declval<U&>().key())>::type,
typename std::decay<decltype(std::declval<U&>().value())>::type>> {};
template <class Container>
using GeneratedType = decltype(
std::declval<const Generator<
typename std::conditional<generator_internal::IsMap<Container>::value,
typename Container::value_type,
typename Container::key_type>::type>&>()());
// Naive wrapper that performs a linear search of previous values.
// Beware this is O(SQR), which is reasonable for smaller kMaxValues.
template <class T, size_t kMaxValues = 64, class E = void>
struct UniqueGenerator {
Generator<T, E> gen;
std::vector<T> values;
T operator()() {
assert(values.size() < kMaxValues);
for (;;) {
T value = gen();
if (std::find(values.begin(), values.end(), value) == values.end()) {
values.push_back(value);
return value;
}
}
}
};
} // namespace hash_internal
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_HASH_GENERATOR_TESTING_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Utilities to help tests verify that hash tables properly handle stateful
// allocators and hash functions.
#ifndef ABSL_CONTAINER_INTERNAL_HASH_POLICY_TESTING_H_
#define ABSL_CONTAINER_INTERNAL_HASH_POLICY_TESTING_H_
#include <cstdlib>
#include <limits>
#include <memory>
#include <ostream>
#include <type_traits>
#include <utility>
#include <vector>
#include "absl/hash/hash.h"
#include "absl/strings/string_view.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
namespace hash_testing_internal {
template <class Derived>
struct WithId {
WithId() : id_(next_id<Derived>()) {}
WithId(const WithId& that) : id_(that.id_) {}
WithId(WithId&& that) : id_(that.id_) { that.id_ = 0; }
WithId& operator=(const WithId& that) {
id_ = that.id_;
return *this;
}
WithId& operator=(WithId&& that) {
id_ = that.id_;
that.id_ = 0;
return *this;
}
size_t id() const { return id_; }
friend bool operator==(const WithId& a, const WithId& b) {
return a.id_ == b.id_;
}
friend bool operator!=(const WithId& a, const WithId& b) { return !(a == b); }
protected:
explicit WithId(size_t id) : id_(id) {}
private:
size_t id_;
template <class T>
static size_t next_id() {
// 0 is reserved for moved from state.
static size_t gId = 1;
return gId++;
}
};
} // namespace hash_testing_internal
struct NonStandardLayout {
NonStandardLayout() {}
explicit NonStandardLayout(std::string s) : value(std::move(s)) {}
virtual ~NonStandardLayout() {}
friend bool operator==(const NonStandardLayout& a,
const NonStandardLayout& b) {
return a.value == b.value;
}
friend bool operator!=(const NonStandardLayout& a,
const NonStandardLayout& b) {
return a.value != b.value;
}
template <typename H>
friend H AbslHashValue(H h, const NonStandardLayout& v) {
return H::combine(std::move(h), v.value);
}
std::string value;
};
struct StatefulTestingHash
: absl::container_internal::hash_testing_internal::WithId<
StatefulTestingHash> {
template <class T>
size_t operator()(const T& t) const {
return absl::Hash<T>{}(t);
}
};
struct StatefulTestingEqual
: absl::container_internal::hash_testing_internal::WithId<
StatefulTestingEqual> {
template <class T, class U>
bool operator()(const T& t, const U& u) const {
return t == u;
}
};
// It is expected that Alloc() == Alloc() for all allocators so we cannot use
// WithId base. We need to explicitly assign ids.
template <class T = int>
struct Alloc : std::allocator<T> {
using propagate_on_container_swap = std::true_type;
// Using old paradigm for this to ensure compatibility.
explicit Alloc(size_t id = 0) : id_(id) {}
Alloc(const Alloc&) = default;
Alloc& operator=(const Alloc&) = default;
template <class U>
Alloc(const Alloc<U>& that) : std::allocator<T>(that), id_(that.id()) {}
template <class U>
struct rebind {
using other = Alloc<U>;
};
size_t id() const { return id_; }
friend bool operator==(const Alloc& a, const Alloc& b) {
return a.id_ == b.id_;
}
friend bool operator!=(const Alloc& a, const Alloc& b) { return !(a == b); }
private:
size_t id_ = (std::numeric_limits<size_t>::max)();
};
template <class Map>
auto items(const Map& m) -> std::vector<
std::pair<typename Map::key_type, typename Map::mapped_type>> {
using std::get;
std::vector<std::pair<typename Map::key_type, typename Map::mapped_type>> res;
res.reserve(m.size());
for (const auto& v : m) res.emplace_back(get<0>(v), get<1>(v));
return res;
}
template <class Set>
auto keys(const Set& s)
-> std::vector<typename std::decay<typename Set::key_type>::type> {
std::vector<typename std::decay<typename Set::key_type>::type> res;
res.reserve(s.size());
for (const auto& v : s) res.emplace_back(v);
return res;
}
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
// ABSL_UNORDERED_SUPPORTS_ALLOC_CTORS is false for glibcxx versions
// where the unordered containers are missing certain constructors that
// take allocator arguments. This test is defined ad-hoc for the platforms
// we care about (notably Crosstool 17) because libstdcxx's useless
// versioning scheme precludes a more principled solution.
// From GCC-4.9 Changelog: (src: https://gcc.gnu.org/gcc-4.9/changes.html)
// "the unordered associative containers in <unordered_map> and <unordered_set>
// meet the allocator-aware container requirements;"
#if (defined(__GLIBCXX__) && __GLIBCXX__ <= 20140425 ) || \
( __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 9 ))
#define ABSL_UNORDERED_SUPPORTS_ALLOC_CTORS 0
#else
#define ABSL_UNORDERED_SUPPORTS_ALLOC_CTORS 1
#endif
#endif // ABSL_CONTAINER_INTERNAL_HASH_POLICY_TESTING_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_HASH_POLICY_TRAITS_H_
#define ABSL_CONTAINER_INTERNAL_HASH_POLICY_TRAITS_H_
#include <cstddef>
#include <memory>
#include <new>
#include <type_traits>
#include <utility>
#include "absl/container/internal/common_policy_traits.h"
#include "absl/meta/type_traits.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// Defines how slots are initialized/destroyed/moved.
template <class Policy, class = void>
struct hash_policy_traits : common_policy_traits<Policy> {
// The type of the keys stored in the hashtable.
using key_type = typename Policy::key_type;
private:
struct ReturnKey {
// When C++17 is available, we can use std::launder to provide mutable
// access to the key for use in node handle.
#if defined(__cpp_lib_launder) && __cpp_lib_launder >= 201606
template <class Key,
absl::enable_if_t<std::is_lvalue_reference<Key>::value, int> = 0>
static key_type& Impl(Key&& k, int) {
return *std::launder(
const_cast<key_type*>(std::addressof(std::forward<Key>(k))));
}
#endif
template <class Key>
static Key Impl(Key&& k, char) {
return std::forward<Key>(k);
}
// When Key=T&, we forward the lvalue reference.
// When Key=T, we return by value to avoid a dangling reference.
// eg, for string_hash_map.
template <class Key, class... Args>
auto operator()(Key&& k, const Args&...) const
-> decltype(Impl(std::forward<Key>(k), 0)) {
return Impl(std::forward<Key>(k), 0);
}
};
template <class P = Policy, class = void>
struct ConstantIteratorsImpl : std::false_type {};
template <class P>
struct ConstantIteratorsImpl<P, absl::void_t<typename P::constant_iterators>>
: P::constant_iterators {};
public:
// The actual object stored in the hash table.
using slot_type = typename Policy::slot_type;
// The argument type for insertions into the hashtable. This is different
// from value_type for increased performance. See initializer_list constructor
// and insert() member functions for more details.
using init_type = typename Policy::init_type;
using reference = decltype(Policy::element(std::declval<slot_type*>()));
using pointer = typename std::remove_reference<reference>::type*;
using value_type = typename std::remove_reference<reference>::type;
// Policies can set this variable to tell raw_hash_set that all iterators
// should be constant, even `iterator`. This is useful for set-like
// containers.
// Defaults to false if not provided by the policy.
using constant_iterators = ConstantIteratorsImpl<>;
// Returns the amount of memory owned by `slot`, exclusive of `sizeof(*slot)`.
//
// If `slot` is nullptr, returns the constant amount of memory owned by any
// full slot or -1 if slots own variable amounts of memory.
//
// PRECONDITION: `slot` is INITIALIZED or nullptr
template <class P = Policy>
static size_t space_used(const slot_type* slot) {
return P::space_used(slot);
}
// Provides generalized access to the key for elements, both for elements in
// the table and for elements that have not yet been inserted (or even
// constructed). We would like an API that allows us to say: `key(args...)`
// but we cannot do that for all cases, so we use this more general API that
// can be used for many things, including the following:
//
// - Given an element in a table, get its key.
// - Given an element initializer, get its key.
// - Given `emplace()` arguments, get the element key.
//
// Implementations of this must adhere to a very strict technical
// specification around aliasing and consuming arguments:
//
// Let `value_type` be the result type of `element()` without ref- and
// cv-qualifiers. The first argument is a functor, the rest are constructor
// arguments for `value_type`. Returns `std::forward<F>(f)(k, xs...)`, where
// `k` is the element key, and `xs...` are the new constructor arguments for
// `value_type`. It's allowed for `k` to alias `xs...`, and for both to alias
// `ts...`. The key won't be touched once `xs...` are used to construct an
// element; `ts...` won't be touched at all, which allows `apply()` to consume
// any rvalues among them.
//
// If `value_type` is constructible from `Ts&&...`, `Policy::apply()` must not
// trigger a hard compile error unless it originates from `f`. In other words,
// `Policy::apply()` must be SFINAE-friendly. If `value_type` is not
// constructible from `Ts&&...`, either SFINAE or a hard compile error is OK.
//
// If `Ts...` is `[cv] value_type[&]` or `[cv] init_type[&]`,
// `Policy::apply()` must work. A compile error is not allowed, SFINAE or not.
template <class F, class... Ts, class P = Policy>
static auto apply(F&& f, Ts&&... ts)
-> decltype(P::apply(std::forward<F>(f), std::forward<Ts>(ts)...)) {
return P::apply(std::forward<F>(f), std::forward<Ts>(ts)...);
}
// Returns the "key" portion of the slot.
// Used for node handle manipulation.
template <class P = Policy>
static auto mutable_key(slot_type* slot)
-> decltype(P::apply(ReturnKey(), hash_policy_traits::element(slot))) {
return P::apply(ReturnKey(), hash_policy_traits::element(slot));
}
// Returns the "value" (as opposed to the "key") portion of the element. Used
// by maps to implement `operator[]`, `at()` and `insert_or_assign()`.
template <class T, class P = Policy>
static auto value(T* elem) -> decltype(P::value(elem)) {
return P::value(elem);
}
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_HASH_POLICY_TRAITS_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// This library provides APIs to debug the probing behavior of hash tables.
//
// In general, the probing behavior is a black box for users and only the
// side effects can be measured in the form of performance differences.
// These APIs give a glimpse on the actual behavior of the probing algorithms in
// these hashtables given a specified hash function and a set of elements.
//
// The probe count distribution can be used to assess the quality of the hash
// function for that particular hash table. Note that a hash function that
// performs well in one hash table implementation does not necessarily performs
// well in a different one.
//
// This library supports std::unordered_{set,map}, dense_hash_{set,map} and
// absl::{flat,node,string}_hash_{set,map}.
#ifndef ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_H_
#define ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_H_
#include <cstddef>
#include <algorithm>
#include <type_traits>
#include <vector>
#include "absl/container/internal/hashtable_debug_hooks.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// Returns the number of probes required to lookup `key`. Returns 0 for a
// search with no collisions. Higher values mean more hash collisions occurred;
// however, the exact meaning of this number varies according to the container
// type.
template <typename C>
size_t GetHashtableDebugNumProbes(
const C& c, const typename C::key_type& key) {
return absl::container_internal::hashtable_debug_internal::
HashtableDebugAccess<C>::GetNumProbes(c, key);
}
// Gets a histogram of the number of probes for each elements in the container.
// The sum of all the values in the vector is equal to container.size().
template <typename C>
std::vector<size_t> GetHashtableDebugNumProbesHistogram(const C& container) {
std::vector<size_t> v;
for (auto it = container.begin(); it != container.end(); ++it) {
size_t num_probes = GetHashtableDebugNumProbes(
container,
absl::container_internal::hashtable_debug_internal::GetKey<C>(*it, 0));
v.resize((std::max)(v.size(), num_probes + 1));
v[num_probes]++;
}
return v;
}
struct HashtableDebugProbeSummary {
size_t total_elements;
size_t total_num_probes;
double mean;
};
// Gets a summary of the probe count distribution for the elements in the
// container.
template <typename C>
HashtableDebugProbeSummary GetHashtableDebugProbeSummary(const C& container) {
auto probes = GetHashtableDebugNumProbesHistogram(container);
HashtableDebugProbeSummary summary = {};
for (size_t i = 0; i < probes.size(); ++i) {
summary.total_elements += probes[i];
summary.total_num_probes += probes[i] * i;
}
summary.mean = 1.0 * summary.total_num_probes / summary.total_elements;
return summary;
}
// Returns the number of bytes requested from the allocator by the container
// and not freed.
template <typename C>
size_t AllocatedByteSize(const C& c) {
return absl::container_internal::hashtable_debug_internal::
HashtableDebugAccess<C>::AllocatedByteSize(c);
}
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Provides the internal API for hashtable_debug.h.
#ifndef ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_HOOKS_H_
#define ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_HOOKS_H_
#include <cstddef>
#include <algorithm>
#include <type_traits>
#include <vector>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
namespace hashtable_debug_internal {
// If it is a map, call get<0>().
using std::get;
template <typename T, typename = typename T::mapped_type>
auto GetKey(const typename T::value_type& pair, int) -> decltype(get<0>(pair)) {
return get<0>(pair);
}
// If it is not a map, return the value directly.
template <typename T>
const typename T::key_type& GetKey(const typename T::key_type& key, char) {
return key;
}
// Containers should specialize this to provide debug information for that
// container.
template <class Container, typename Enabler = void>
struct HashtableDebugAccess {
// Returns the number of probes required to find `key` in `c`. The "number of
// probes" is a concept that can vary by container. Implementations should
// return 0 when `key` was found in the minimum number of operations and
// should increment the result for each non-trivial operation required to find
// `key`.
//
// The default implementation uses the bucket api from the standard and thus
// works for `std::unordered_*` containers.
static size_t GetNumProbes(const Container& c,
const typename Container::key_type& key) {
if (!c.bucket_count()) return {};
size_t num_probes = 0;
size_t bucket = c.bucket(key);
for (auto it = c.begin(bucket), e = c.end(bucket);; ++it, ++num_probes) {
if (it == e) return num_probes;
if (c.key_eq()(key, GetKey<Container>(*it, 0))) return num_probes;
}
}
// Returns the number of bytes requested from the allocator by the container
// and not freed.
//
// static size_t AllocatedByteSize(const Container& c);
// Returns a tight lower bound for AllocatedByteSize(c) where `c` is of type
// `Container` and `c.size()` is equal to `num_elements`.
//
// static size_t LowerBoundAllocatedByteSize(size_t num_elements);
};
} // namespace hashtable_debug_internal
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_HOOKS_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: hashtablez_sampler.h
// -----------------------------------------------------------------------------
//
// This header file defines the API for a low level library to sample hashtables
// and collect runtime statistics about them.
//
// `HashtablezSampler` controls the lifecycle of `HashtablezInfo` objects which
// store information about a single sample.
//
// `Record*` methods store information into samples.
// `Sample()` and `Unsample()` make use of a single global sampler with
// properties controlled by the flags hashtablez_enabled,
// hashtablez_sample_rate, and hashtablez_max_samples.
//
// WARNING
//
// Using this sampling API may cause sampled Swiss tables to use the global
// allocator (operator `new`) in addition to any custom allocator. If you
// are using a table in an unusual circumstance where allocation or calling a
// linux syscall is unacceptable, this could interfere.
//
// This utility is internal-only. Use at your own risk.
#ifndef ABSL_CONTAINER_INTERNAL_HASHTABLEZ_SAMPLER_H_
#define ABSL_CONTAINER_INTERNAL_HASHTABLEZ_SAMPLER_H_
#include <atomic>
#include <functional>
#include <memory>
#include <vector>
#include "absl/base/config.h"
#include "absl/base/internal/per_thread_tls.h"
#include "absl/base/optimization.h"
#include "absl/profiling/internal/sample_recorder.h"
#include "absl/synchronization/mutex.h"
#include "absl/utility/utility.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// Stores information about a sampled hashtable. All mutations to this *must*
// be made through `Record*` functions below. All reads from this *must* only
// occur in the callback to `HashtablezSampler::Iterate`.
struct HashtablezInfo : public profiling_internal::Sample<HashtablezInfo> {
// Constructs the object but does not fill in any fields.
HashtablezInfo();
~HashtablezInfo();
HashtablezInfo(const HashtablezInfo&) = delete;
HashtablezInfo& operator=(const HashtablezInfo&) = delete;
// Puts the object into a clean state, fills in the logically `const` members,
// blocking for any readers that are currently sampling the object.
void PrepareForSampling(int64_t stride, size_t inline_element_size_value)
ABSL_EXCLUSIVE_LOCKS_REQUIRED(init_mu);
// These fields are mutated by the various Record* APIs and need to be
// thread-safe.
std::atomic<size_t> capacity;
std::atomic<size_t> size;
std::atomic<size_t> num_erases;
std::atomic<size_t> num_rehashes;
std::atomic<size_t> max_probe_length;
std::atomic<size_t> total_probe_length;
std::atomic<size_t> hashes_bitwise_or;
std::atomic<size_t> hashes_bitwise_and;
std::atomic<size_t> hashes_bitwise_xor;
std::atomic<size_t> max_reserve;
// All of the fields below are set by `PrepareForSampling`, they must not be
// mutated in `Record*` functions. They are logically `const` in that sense.
// These are guarded by init_mu, but that is not externalized to clients,
// which can read them only during `SampleRecorder::Iterate` which will hold
// the lock.
static constexpr int kMaxStackDepth = 64;
absl::Time create_time;
int32_t depth;
void* stack[kMaxStackDepth];
size_t inline_element_size; // How big is the slot?
};
void RecordRehashSlow(HashtablezInfo* info, size_t total_probe_length);
void RecordReservationSlow(HashtablezInfo* info, size_t target_capacity);
void RecordClearedReservationSlow(HashtablezInfo* info);
void RecordStorageChangedSlow(HashtablezInfo* info, size_t size,
size_t capacity);
void RecordInsertSlow(HashtablezInfo* info, size_t hash,
size_t distance_from_desired);
void RecordEraseSlow(HashtablezInfo* info);
struct SamplingState {
int64_t next_sample;
// When we make a sampling decision, we record that distance so we can weight
// each sample.
int64_t sample_stride;
};
HashtablezInfo* SampleSlow(SamplingState& next_sample,
size_t inline_element_size);
void UnsampleSlow(HashtablezInfo* info);
#if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
#error ABSL_INTERNAL_HASHTABLEZ_SAMPLE cannot be directly set
#endif // defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
#if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
class HashtablezInfoHandle {
public:
explicit HashtablezInfoHandle() : info_(nullptr) {}
explicit HashtablezInfoHandle(HashtablezInfo* info) : info_(info) {}
// We do not have a destructor. Caller is responsible for calling Unregister
// before destroying the handle.
void Unregister() {
if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
UnsampleSlow(info_);
}
inline bool IsSampled() const { return ABSL_PREDICT_FALSE(info_ != nullptr); }
inline void RecordStorageChanged(size_t size, size_t capacity) {
if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
RecordStorageChangedSlow(info_, size, capacity);
}
inline void RecordRehash(size_t total_probe_length) {
if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
RecordRehashSlow(info_, total_probe_length);
}
inline void RecordReservation(size_t target_capacity) {
if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
RecordReservationSlow(info_, target_capacity);
}
inline void RecordClearedReservation() {
if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
RecordClearedReservationSlow(info_);
}
inline void RecordInsert(size_t hash, size_t distance_from_desired) {
if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
RecordInsertSlow(info_, hash, distance_from_desired);
}
inline void RecordErase() {
if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
RecordEraseSlow(info_);
}
friend inline void swap(HashtablezInfoHandle& lhs,
HashtablezInfoHandle& rhs) {
std::swap(lhs.info_, rhs.info_);
}
private:
friend class HashtablezInfoHandlePeer;
HashtablezInfo* info_;
};
#else
// Ensure that when Hashtablez is turned off at compile time, HashtablezInfo can
// be removed by the linker, in order to reduce the binary size.
class HashtablezInfoHandle {
public:
explicit HashtablezInfoHandle() = default;
explicit HashtablezInfoHandle(std::nullptr_t) {}
inline void Unregister() {}
inline bool IsSampled() const { return false; }
inline void RecordStorageChanged(size_t /*size*/, size_t /*capacity*/) {}
inline void RecordRehash(size_t /*total_probe_length*/) {}
inline void RecordReservation(size_t /*target_capacity*/) {}
inline void RecordClearedReservation() {}
inline void RecordInsert(size_t /*hash*/, size_t /*distance_from_desired*/) {}
inline void RecordErase() {}
friend inline void swap(HashtablezInfoHandle& /*lhs*/,
HashtablezInfoHandle& /*rhs*/) {}
};
#endif // defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
#if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
extern ABSL_PER_THREAD_TLS_KEYWORD SamplingState global_next_sample;
#endif // defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
// Returns an RAII sampling handle that manages registration and unregistation
// with the global sampler.
inline HashtablezInfoHandle Sample(
size_t inline_element_size ABSL_ATTRIBUTE_UNUSED) {
#if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
if (ABSL_PREDICT_TRUE(--global_next_sample.next_sample > 0)) {
return HashtablezInfoHandle(nullptr);
}
return HashtablezInfoHandle(
SampleSlow(global_next_sample, inline_element_size));
#else
return HashtablezInfoHandle(nullptr);
#endif // !ABSL_PER_THREAD_TLS
}
using HashtablezSampler =
::absl::profiling_internal::SampleRecorder<HashtablezInfo>;
// Returns a global Sampler.
HashtablezSampler& GlobalHashtablezSampler();
using HashtablezConfigListener = void (*)();
void SetHashtablezConfigListener(HashtablezConfigListener l);
// Enables or disables sampling for Swiss tables.
bool IsHashtablezEnabled();
void SetHashtablezEnabled(bool enabled);
void SetHashtablezEnabledInternal(bool enabled);
// Sets the rate at which Swiss tables will be sampled.
int32_t GetHashtablezSampleParameter();
void SetHashtablezSampleParameter(int32_t rate);
void SetHashtablezSampleParameterInternal(int32_t rate);
// Sets a soft max for the number of samples that will be kept.
size_t GetHashtablezMaxSamples();
void SetHashtablezMaxSamples(size_t max);
void SetHashtablezMaxSamplesInternal(size_t max);
// Configuration override.
// This allows process-wide sampling without depending on order of
// initialization of static storage duration objects.
// The definition of this constant is weak, which allows us to inject a
// different value for it at link time.
extern "C" bool ABSL_INTERNAL_C_SYMBOL(AbslContainerInternalSampleEverything)();
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_HASHTABLEZ_SAMPLER_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// MOTIVATION AND TUTORIAL
//
// If you want to put in a single heap allocation N doubles followed by M ints,
// it's easy if N and M are known at compile time.
//
// struct S {
// double a[N];
// int b[M];
// };
//
// S* p = new S;
//
// But what if N and M are known only in run time? Class template Layout to the
// rescue! It's a portable generalization of the technique known as struct hack.
//
// // This object will tell us everything we need to know about the memory
// // layout of double[N] followed by int[M]. It's structurally identical to
// // size_t[2] that stores N and M. It's very cheap to create.
// const Layout<double, int> layout(N, M);
//
// // Allocate enough memory for both arrays. `AllocSize()` tells us how much
// // memory is needed. We are free to use any allocation function we want as
// // long as it returns aligned memory.
// std::unique_ptr<unsigned char[]> p(new unsigned char[layout.AllocSize()]);
//
// // Obtain the pointer to the array of doubles.
// // Equivalent to `reinterpret_cast<double*>(p.get())`.
// //
// // We could have written layout.Pointer<0>(p) instead. If all the types are
// // unique you can use either form, but if some types are repeated you must
// // use the index form.
// double* a = layout.Pointer<double>(p.get());
//
// // Obtain the pointer to the array of ints.
// // Equivalent to `reinterpret_cast<int*>(p.get() + N * 8)`.
// int* b = layout.Pointer<int>(p);
//
// If we are unable to specify sizes of all fields, we can pass as many sizes as
// we can to `Partial()`. In return, it'll allow us to access the fields whose
// locations and sizes can be computed from the provided information.
// `Partial()` comes in handy when the array sizes are embedded into the
// allocation.
//
// // size_t[0] containing N, size_t[1] containing M, double[N], int[M].
// using L = Layout<size_t, size_t, double, int>;
//
// unsigned char* Allocate(size_t n, size_t m) {
// const L layout(1, 1, n, m);
// unsigned char* p = new unsigned char[layout.AllocSize()];
// *layout.Pointer<0>(p) = n;
// *layout.Pointer<1>(p) = m;
// return p;
// }
//
// void Use(unsigned char* p) {
// // First, extract N and M.
// // Specify that the first array has only one element. Using `prefix` we
// // can access the first two arrays but not more.
// constexpr auto prefix = L::Partial(1);
// size_t n = *prefix.Pointer<0>(p);
// size_t m = *prefix.Pointer<1>(p);
//
// // Now we can get pointers to the payload.
// const L layout(1, 1, n, m);
// double* a = layout.Pointer<double>(p);
// int* b = layout.Pointer<int>(p);
// }
//
// The layout we used above combines fixed-size with dynamically-sized fields.
// This is quite common. Layout is optimized for this use case and generates
// optimal code. All computations that can be performed at compile time are
// indeed performed at compile time.
//
// Efficiency tip: The order of fields matters. In `Layout<T1, ..., TN>` try to
// ensure that `alignof(T1) >= ... >= alignof(TN)`. This way you'll have no
// padding in between arrays.
//
// You can manually override the alignment of an array by wrapping the type in
// `Aligned<T, N>`. `Layout<..., Aligned<T, N>, ...>` has exactly the same API
// and behavior as `Layout<..., T, ...>` except that the first element of the
// array of `T` is aligned to `N` (the rest of the elements follow without
// padding). `N` cannot be less than `alignof(T)`.
//
// `AllocSize()` and `Pointer()` are the most basic methods for dealing with
// memory layouts. Check out the reference or code below to discover more.
//
// EXAMPLE
//
// // Immutable move-only string with sizeof equal to sizeof(void*). The
// // string size and the characters are kept in the same heap allocation.
// class CompactString {
// public:
// CompactString(const char* s = "") {
// const size_t size = strlen(s);
// // size_t[1] followed by char[size + 1].
// const L layout(1, size + 1);
// p_.reset(new unsigned char[layout.AllocSize()]);
// // If running under ASAN, mark the padding bytes, if any, to catch
// // memory errors.
// layout.PoisonPadding(p_.get());
// // Store the size in the allocation.
// *layout.Pointer<size_t>(p_.get()) = size;
// // Store the characters in the allocation.
// memcpy(layout.Pointer<char>(p_.get()), s, size + 1);
// }
//
// size_t size() const {
// // Equivalent to reinterpret_cast<size_t&>(*p).
// return *L::Partial().Pointer<size_t>(p_.get());
// }
//
// const char* c_str() const {
// // Equivalent to reinterpret_cast<char*>(p.get() + sizeof(size_t)).
// // The argument in Partial(1) specifies that we have size_t[1] in front
// // of the characters.
// return L::Partial(1).Pointer<char>(p_.get());
// }
//
// private:
// // Our heap allocation contains a size_t followed by an array of chars.
// using L = Layout<size_t, char>;
// std::unique_ptr<unsigned char[]> p_;
// };
//
// int main() {
// CompactString s = "hello";
// assert(s.size() == 5);
// assert(strcmp(s.c_str(), "hello") == 0);
// }
//
// DOCUMENTATION
//
// The interface exported by this file consists of:
// - class `Layout<>` and its public members.
// - The public members of class `internal_layout::LayoutImpl<>`. That class
// isn't intended to be used directly, and its name and template parameter
// list are internal implementation details, but the class itself provides
// most of the functionality in this file. See comments on its members for
// detailed documentation.
//
// `Layout<T1,... Tn>::Partial(count1,..., countm)` (where `m` <= `n`) returns a
// `LayoutImpl<>` object. `Layout<T1,..., Tn> layout(count1,..., countn)`
// creates a `Layout` object, which exposes the same functionality by inheriting
// from `LayoutImpl<>`.
#ifndef ABSL_CONTAINER_INTERNAL_LAYOUT_H_
#define ABSL_CONTAINER_INTERNAL_LAYOUT_H_
#include <assert.h>
#include <stddef.h>
#include <stdint.h>
#include <ostream>
#include <string>
#include <tuple>
#include <type_traits>
#include <typeinfo>
#include <utility>
#include "absl/base/config.h"
#include "absl/debugging/internal/demangle.h"
#include "absl/meta/type_traits.h"
#include "absl/strings/str_cat.h"
#include "absl/types/span.h"
#include "absl/utility/utility.h"
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
#include <sanitizer/asan_interface.h>
#endif
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// A type wrapper that instructs `Layout` to use the specific alignment for the
// array. `Layout<..., Aligned<T, N>, ...>` has exactly the same API
// and behavior as `Layout<..., T, ...>` except that the first element of the
// array of `T` is aligned to `N` (the rest of the elements follow without
// padding).
//
// Requires: `N >= alignof(T)` and `N` is a power of 2.
template <class T, size_t N>
struct Aligned;
namespace internal_layout {
template <class T>
struct NotAligned {};
template <class T, size_t N>
struct NotAligned<const Aligned<T, N>> {
static_assert(sizeof(T) == 0, "Aligned<T, N> cannot be const-qualified");
};
template <size_t>
using IntToSize = size_t;
template <class>
using TypeToSize = size_t;
template <class T>
struct Type : NotAligned<T> {
using type = T;
};
template <class T, size_t N>
struct Type<Aligned<T, N>> {
using type = T;
};
template <class T>
struct SizeOf : NotAligned<T>, std::integral_constant<size_t, sizeof(T)> {};
template <class T, size_t N>
struct SizeOf<Aligned<T, N>> : std::integral_constant<size_t, sizeof(T)> {};
// Note: workaround for https://gcc.gnu.org/PR88115
template <class T>
struct AlignOf : NotAligned<T> {
static constexpr size_t value = alignof(T);
};
template <class T, size_t N>
struct AlignOf<Aligned<T, N>> {
static_assert(N % alignof(T) == 0,
"Custom alignment can't be lower than the type's alignment");
static constexpr size_t value = N;
};
// Does `Ts...` contain `T`?
template <class T, class... Ts>
using Contains = absl::disjunction<std::is_same<T, Ts>...>;
template <class From, class To>
using CopyConst =
typename std::conditional<std::is_const<From>::value, const To, To>::type;
// Note: We're not qualifying this with absl:: because it doesn't compile under
// MSVC.
template <class T>
using SliceType = Span<T>;
// This namespace contains no types. It prevents functions defined in it from
// being found by ADL.
namespace adl_barrier {
template <class Needle, class... Ts>
constexpr size_t Find(Needle, Needle, Ts...) {
static_assert(!Contains<Needle, Ts...>(), "Duplicate element type");
return 0;
}
template <class Needle, class T, class... Ts>
constexpr size_t Find(Needle, T, Ts...) {
return adl_barrier::Find(Needle(), Ts()...) + 1;
}
constexpr bool IsPow2(size_t n) { return !(n & (n - 1)); }
// Returns `q * m` for the smallest `q` such that `q * m >= n`.
// Requires: `m` is a power of two. It's enforced by IsLegalElementType below.
constexpr size_t Align(size_t n, size_t m) { return (n + m - 1) & ~(m - 1); }
constexpr size_t Min(size_t a, size_t b) { return b < a ? b : a; }
constexpr size_t Max(size_t a) { return a; }
template <class... Ts>
constexpr size_t Max(size_t a, size_t b, Ts... rest) {
return adl_barrier::Max(b < a ? a : b, rest...);
}
template <class T>
std::string TypeName() {
std::string out;
#if ABSL_INTERNAL_HAS_RTTI
absl::StrAppend(&out, "<",
absl::debugging_internal::DemangleString(typeid(T).name()),
">");
#endif
return out;
}
} // namespace adl_barrier
template <bool C>
using EnableIf = typename std::enable_if<C, int>::type;
// Can `T` be a template argument of `Layout`?
template <class T>
using IsLegalElementType = std::integral_constant<
bool, !std::is_reference<T>::value && !std::is_volatile<T>::value &&
!std::is_reference<typename Type<T>::type>::value &&
!std::is_volatile<typename Type<T>::type>::value &&
adl_barrier::IsPow2(AlignOf<T>::value)>;
template <class Elements, class SizeSeq, class OffsetSeq>
class LayoutImpl;
// Public base class of `Layout` and the result type of `Layout::Partial()`.
//
// `Elements...` contains all template arguments of `Layout` that created this
// instance.
//
// `SizeSeq...` is `[0, NumSizes)` where `NumSizes` is the number of arguments
// passed to `Layout::Partial()` or `Layout::Layout()`.
//
// `OffsetSeq...` is `[0, NumOffsets)` where `NumOffsets` is
// `Min(sizeof...(Elements), NumSizes + 1)` (the number of arrays for which we
// can compute offsets).
template <class... Elements, size_t... SizeSeq, size_t... OffsetSeq>
class LayoutImpl<std::tuple<Elements...>, absl::index_sequence<SizeSeq...>,
absl::index_sequence<OffsetSeq...>> {
private:
static_assert(sizeof...(Elements) > 0, "At least one field is required");
static_assert(absl::conjunction<IsLegalElementType<Elements>...>::value,
"Invalid element type (see IsLegalElementType)");
enum {
NumTypes = sizeof...(Elements),
NumSizes = sizeof...(SizeSeq),
NumOffsets = sizeof...(OffsetSeq),
};
// These are guaranteed by `Layout`.
static_assert(NumOffsets == adl_barrier::Min(NumTypes, NumSizes + 1),
"Internal error");
static_assert(NumTypes > 0, "Internal error");
// Returns the index of `T` in `Elements...`. Results in a compilation error
// if `Elements...` doesn't contain exactly one instance of `T`.
template <class T>
static constexpr size_t ElementIndex() {
static_assert(Contains<Type<T>, Type<typename Type<Elements>::type>...>(),
"Type not found");
return adl_barrier::Find(Type<T>(),
Type<typename Type<Elements>::type>()...);
}
template <size_t N>
using ElementAlignment =
AlignOf<typename std::tuple_element<N, std::tuple<Elements...>>::type>;
public:
// Element types of all arrays packed in a tuple.
using ElementTypes = std::tuple<typename Type<Elements>::type...>;
// Element type of the Nth array.
template <size_t N>
using ElementType = typename std::tuple_element<N, ElementTypes>::type;
constexpr explicit LayoutImpl(IntToSize<SizeSeq>... sizes)
: size_{sizes...} {}
// Alignment of the layout, equal to the strictest alignment of all elements.
// All pointers passed to the methods of layout must be aligned to this value.
static constexpr size_t Alignment() {
return adl_barrier::Max(AlignOf<Elements>::value...);
}
// Offset in bytes of the Nth array.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// assert(x.Offset<0>() == 0); // The ints starts from 0.
// assert(x.Offset<1>() == 16); // The doubles starts from 16.
//
// Requires: `N <= NumSizes && N < sizeof...(Ts)`.
template <size_t N, EnableIf<N == 0> = 0>
constexpr size_t Offset() const {
return 0;
}
template <size_t N, EnableIf<N != 0> = 0>
constexpr size_t Offset() const {
static_assert(N < NumOffsets, "Index out of bounds");
return adl_barrier::Align(
Offset<N - 1>() + SizeOf<ElementType<N - 1>>::value * size_[N - 1],
ElementAlignment<N>::value);
}
// Offset in bytes of the array with the specified element type. There must
// be exactly one such array and its zero-based index must be at most
// `NumSizes`.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// assert(x.Offset<int>() == 0); // The ints starts from 0.
// assert(x.Offset<double>() == 16); // The doubles starts from 16.
template <class T>
constexpr size_t Offset() const {
return Offset<ElementIndex<T>()>();
}
// Offsets in bytes of all arrays for which the offsets are known.
constexpr std::array<size_t, NumOffsets> Offsets() const {
return {{Offset<OffsetSeq>()...}};
}
// The number of elements in the Nth array. This is the Nth argument of
// `Layout::Partial()` or `Layout::Layout()` (zero-based).
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// assert(x.Size<0>() == 3);
// assert(x.Size<1>() == 4);
//
// Requires: `N < NumSizes`.
template <size_t N>
constexpr size_t Size() const {
static_assert(N < NumSizes, "Index out of bounds");
return size_[N];
}
// The number of elements in the array with the specified element type.
// There must be exactly one such array and its zero-based index must be
// at most `NumSizes`.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// assert(x.Size<int>() == 3);
// assert(x.Size<double>() == 4);
template <class T>
constexpr size_t Size() const {
return Size<ElementIndex<T>()>();
}
// The number of elements of all arrays for which they are known.
constexpr std::array<size_t, NumSizes> Sizes() const {
return {{Size<SizeSeq>()...}};
}
// Pointer to the beginning of the Nth array.
//
// `Char` must be `[const] [signed|unsigned] char`.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// unsigned char* p = new unsigned char[x.AllocSize()];
// int* ints = x.Pointer<0>(p);
// double* doubles = x.Pointer<1>(p);
//
// Requires: `N <= NumSizes && N < sizeof...(Ts)`.
// Requires: `p` is aligned to `Alignment()`.
template <size_t N, class Char>
CopyConst<Char, ElementType<N>>* Pointer(Char* p) const {
using C = typename std::remove_const<Char>::type;
static_assert(
std::is_same<C, char>() || std::is_same<C, unsigned char>() ||
std::is_same<C, signed char>(),
"The argument must be a pointer to [const] [signed|unsigned] char");
constexpr size_t alignment = Alignment();
(void)alignment;
assert(reinterpret_cast<uintptr_t>(p) % alignment == 0);
return reinterpret_cast<CopyConst<Char, ElementType<N>>*>(p + Offset<N>());
}
// Pointer to the beginning of the array with the specified element type.
// There must be exactly one such array and its zero-based index must be at
// most `NumSizes`.
//
// `Char` must be `[const] [signed|unsigned] char`.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// unsigned char* p = new unsigned char[x.AllocSize()];
// int* ints = x.Pointer<int>(p);
// double* doubles = x.Pointer<double>(p);
//
// Requires: `p` is aligned to `Alignment()`.
template <class T, class Char>
CopyConst<Char, T>* Pointer(Char* p) const {
return Pointer<ElementIndex<T>()>(p);
}
// Pointers to all arrays for which pointers are known.
//
// `Char` must be `[const] [signed|unsigned] char`.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// unsigned char* p = new unsigned char[x.AllocSize()];
//
// int* ints;
// double* doubles;
// std::tie(ints, doubles) = x.Pointers(p);
//
// Requires: `p` is aligned to `Alignment()`.
//
// Note: We're not using ElementType alias here because it does not compile
// under MSVC.
template <class Char>
std::tuple<CopyConst<
Char, typename std::tuple_element<OffsetSeq, ElementTypes>::type>*...>
Pointers(Char* p) const {
return std::tuple<CopyConst<Char, ElementType<OffsetSeq>>*...>(
Pointer<OffsetSeq>(p)...);
}
// The Nth array.
//
// `Char` must be `[const] [signed|unsigned] char`.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// unsigned char* p = new unsigned char[x.AllocSize()];
// Span<int> ints = x.Slice<0>(p);
// Span<double> doubles = x.Slice<1>(p);
//
// Requires: `N < NumSizes`.
// Requires: `p` is aligned to `Alignment()`.
template <size_t N, class Char>
SliceType<CopyConst<Char, ElementType<N>>> Slice(Char* p) const {
return SliceType<CopyConst<Char, ElementType<N>>>(Pointer<N>(p), Size<N>());
}
// The array with the specified element type. There must be exactly one
// such array and its zero-based index must be less than `NumSizes`.
//
// `Char` must be `[const] [signed|unsigned] char`.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// unsigned char* p = new unsigned char[x.AllocSize()];
// Span<int> ints = x.Slice<int>(p);
// Span<double> doubles = x.Slice<double>(p);
//
// Requires: `p` is aligned to `Alignment()`.
template <class T, class Char>
SliceType<CopyConst<Char, T>> Slice(Char* p) const {
return Slice<ElementIndex<T>()>(p);
}
// All arrays with known sizes.
//
// `Char` must be `[const] [signed|unsigned] char`.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// unsigned char* p = new unsigned char[x.AllocSize()];
//
// Span<int> ints;
// Span<double> doubles;
// std::tie(ints, doubles) = x.Slices(p);
//
// Requires: `p` is aligned to `Alignment()`.
//
// Note: We're not using ElementType alias here because it does not compile
// under MSVC.
template <class Char>
std::tuple<SliceType<CopyConst<
Char, typename std::tuple_element<SizeSeq, ElementTypes>::type>>...>
Slices(Char* p) const {
// Workaround for https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63875 (fixed
// in 6.1).
(void)p;
return std::tuple<SliceType<CopyConst<Char, ElementType<SizeSeq>>>...>(
Slice<SizeSeq>(p)...);
}
// The size of the allocation that fits all arrays.
//
// // int[3], 4 bytes of padding, double[4].
// Layout<int, double> x(3, 4);
// unsigned char* p = new unsigned char[x.AllocSize()]; // 48 bytes
//
// Requires: `NumSizes == sizeof...(Ts)`.
constexpr size_t AllocSize() const {
static_assert(NumTypes == NumSizes, "You must specify sizes of all fields");
return Offset<NumTypes - 1>() +
SizeOf<ElementType<NumTypes - 1>>::value * size_[NumTypes - 1];
}
// If built with --config=asan, poisons padding bytes (if any) in the
// allocation. The pointer must point to a memory block at least
// `AllocSize()` bytes in length.
//
// `Char` must be `[const] [signed|unsigned] char`.
//
// Requires: `p` is aligned to `Alignment()`.
template <class Char, size_t N = NumOffsets - 1, EnableIf<N == 0> = 0>
void PoisonPadding(const Char* p) const {
Pointer<0>(p); // verify the requirements on `Char` and `p`
}
template <class Char, size_t N = NumOffsets - 1, EnableIf<N != 0> = 0>
void PoisonPadding(const Char* p) const {
static_assert(N < NumOffsets, "Index out of bounds");
(void)p;
#ifdef ABSL_HAVE_ADDRESS_SANITIZER
PoisonPadding<Char, N - 1>(p);
// The `if` is an optimization. It doesn't affect the observable behaviour.
if (ElementAlignment<N - 1>::value % ElementAlignment<N>::value) {
size_t start =
Offset<N - 1>() + SizeOf<ElementType<N - 1>>::value * size_[N - 1];
ASAN_POISON_MEMORY_REGION(p + start, Offset<N>() - start);
}
#endif
}
// Human-readable description of the memory layout. Useful for debugging.
// Slow.
//
// // char[5], 3 bytes of padding, int[3], 4 bytes of padding, followed
// // by an unknown number of doubles.
// auto x = Layout<char, int, double>::Partial(5, 3);
// assert(x.DebugString() ==
// "@0<char>(1)[5]; @8<int>(4)[3]; @24<double>(8)");
//
// Each field is in the following format: @offset<type>(sizeof)[size] (<type>
// may be missing depending on the target platform). For example,
// @8<int>(4)[3] means that at offset 8 we have an array of ints, where each
// int is 4 bytes, and we have 3 of those ints. The size of the last field may
// be missing (as in the example above). Only fields with known offsets are
// described. Type names may differ across platforms: one compiler might
// produce "unsigned*" where another produces "unsigned int *".
std::string DebugString() const {
const auto offsets = Offsets();
const size_t sizes[] = {SizeOf<ElementType<OffsetSeq>>::value...};
const std::string types[] = {
adl_barrier::TypeName<ElementType<OffsetSeq>>()...};
std::string res = absl::StrCat("@0", types[0], "(", sizes[0], ")");
for (size_t i = 0; i != NumOffsets - 1; ++i) {
absl::StrAppend(&res, "[", size_[i], "]; @", offsets[i + 1], types[i + 1],
"(", sizes[i + 1], ")");
}
// NumSizes is a constant that may be zero. Some compilers cannot see that
// inside the if statement "size_[NumSizes - 1]" must be valid.
int last = static_cast<int>(NumSizes) - 1;
if (NumTypes == NumSizes && last >= 0) {
absl::StrAppend(&res, "[", size_[last], "]");
}
return res;
}
private:
// Arguments of `Layout::Partial()` or `Layout::Layout()`.
size_t size_[NumSizes > 0 ? NumSizes : 1];
};
template <size_t NumSizes, class... Ts>
using LayoutType = LayoutImpl<
std::tuple<Ts...>, absl::make_index_sequence<NumSizes>,
absl::make_index_sequence<adl_barrier::Min(sizeof...(Ts), NumSizes + 1)>>;
} // namespace internal_layout
// Descriptor of arrays of various types and sizes laid out in memory one after
// another. See the top of the file for documentation.
//
// Check out the public API of internal_layout::LayoutImpl above. The type is
// internal to the library but its methods are public, and they are inherited
// by `Layout`.
template <class... Ts>
class Layout : public internal_layout::LayoutType<sizeof...(Ts), Ts...> {
public:
static_assert(sizeof...(Ts) > 0, "At least one field is required");
static_assert(
absl::conjunction<internal_layout::IsLegalElementType<Ts>...>::value,
"Invalid element type (see IsLegalElementType)");
// The result type of `Partial()` with `NumSizes` arguments.
template <size_t NumSizes>
using PartialType = internal_layout::LayoutType<NumSizes, Ts...>;
// `Layout` knows the element types of the arrays we want to lay out in
// memory but not the number of elements in each array.
// `Partial(size1, ..., sizeN)` allows us to specify the latter. The
// resulting immutable object can be used to obtain pointers to the
// individual arrays.
//
// It's allowed to pass fewer array sizes than the number of arrays. E.g.,
// if all you need is to the offset of the second array, you only need to
// pass one argument -- the number of elements in the first array.
//
// // int[3] followed by 4 bytes of padding and an unknown number of
// // doubles.
// auto x = Layout<int, double>::Partial(3);
// // doubles start at byte 16.
// assert(x.Offset<1>() == 16);
//
// If you know the number of elements in all arrays, you can still call
// `Partial()` but it's more convenient to use the constructor of `Layout`.
//
// Layout<int, double> x(3, 5);
//
// Note: The sizes of the arrays must be specified in number of elements,
// not in bytes.
//
// Requires: `sizeof...(Sizes) <= sizeof...(Ts)`.
// Requires: all arguments are convertible to `size_t`.
template <class... Sizes>
static constexpr PartialType<sizeof...(Sizes)> Partial(Sizes&&... sizes) {
static_assert(sizeof...(Sizes) <= sizeof...(Ts), "");
return PartialType<sizeof...(Sizes)>(absl::forward<Sizes>(sizes)...);
}
// Creates a layout with the sizes of all arrays specified. If you know
// only the sizes of the first N arrays (where N can be zero), you can use
// `Partial()` defined above. The constructor is essentially equivalent to
// calling `Partial()` and passing in all array sizes; the constructor is
// provided as a convenient abbreviation.
//
// Note: The sizes of the arrays must be specified in number of elements,
// not in bytes.
constexpr explicit Layout(internal_layout::TypeToSize<Ts>... sizes)
: internal_layout::LayoutType<sizeof...(Ts), Ts...>(sizes...) {}
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_LAYOUT_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Adapts a policy for nodes.
//
// The node policy should model:
//
// struct Policy {
// // Returns a new node allocated and constructed using the allocator, using
// // the specified arguments.
// template <class Alloc, class... Args>
// value_type* new_element(Alloc* alloc, Args&&... args) const;
//
// // Destroys and deallocates node using the allocator.
// template <class Alloc>
// void delete_element(Alloc* alloc, value_type* node) const;
// };
//
// It may also optionally define `value()` and `apply()`. For documentation on
// these, see hash_policy_traits.h.
#ifndef ABSL_CONTAINER_INTERNAL_NODE_SLOT_POLICY_H_
#define ABSL_CONTAINER_INTERNAL_NODE_SLOT_POLICY_H_
#include <cassert>
#include <cstddef>
#include <memory>
#include <type_traits>
#include <utility>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class Reference, class Policy>
struct node_slot_policy {
static_assert(std::is_lvalue_reference<Reference>::value, "");
using slot_type = typename std::remove_cv<
typename std::remove_reference<Reference>::type>::type*;
template <class Alloc, class... Args>
static void construct(Alloc* alloc, slot_type* slot, Args&&... args) {
*slot = Policy::new_element(alloc, std::forward<Args>(args)...);
}
template <class Alloc>
static void destroy(Alloc* alloc, slot_type* slot) {
Policy::delete_element(alloc, *slot);
}
// Returns true_type to indicate that transfer can use memcpy.
template <class Alloc>
static std::true_type transfer(Alloc*, slot_type* new_slot,
slot_type* old_slot) {
*new_slot = *old_slot;
return {};
}
static size_t space_used(const slot_type* slot) {
if (slot == nullptr) return Policy::element_space_used(nullptr);
return Policy::element_space_used(*slot);
}
static Reference element(slot_type* slot) { return **slot; }
template <class T, class P = Policy>
static auto value(T* elem) -> decltype(P::value(elem)) {
return P::value(elem);
}
template <class... Ts, class P = Policy>
static auto apply(Ts&&... ts) -> decltype(P::apply(std::forward<Ts>(ts)...)) {
return P::apply(std::forward<Ts>(ts)...);
}
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_NODE_SLOT_POLICY_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_RAW_HASH_MAP_H_
#define ABSL_CONTAINER_INTERNAL_RAW_HASH_MAP_H_
#include <tuple>
#include <type_traits>
#include <utility>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#include "absl/base/internal/throw_delegate.h"
#include "absl/container/internal/container_memory.h"
#include "absl/container/internal/raw_hash_set.h" // IWYU pragma: export
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class Policy, class Hash, class Eq, class Alloc>
class raw_hash_map : public raw_hash_set<Policy, Hash, Eq, Alloc> {
// P is Policy. It's passed as a template argument to support maps that have
// incomplete types as values, as in unordered_map<K, IncompleteType>.
// MappedReference<> may be a non-reference type.
template <class P>
using MappedReference = decltype(P::value(
std::addressof(std::declval<typename raw_hash_map::reference>())));
// MappedConstReference<> may be a non-reference type.
template <class P>
using MappedConstReference = decltype(P::value(
std::addressof(std::declval<typename raw_hash_map::const_reference>())));
using KeyArgImpl =
KeyArg<IsTransparent<Eq>::value && IsTransparent<Hash>::value>;
public:
using key_type = typename Policy::key_type;
using mapped_type = typename Policy::mapped_type;
template <class K>
using key_arg = typename KeyArgImpl::template type<K, key_type>;
static_assert(!std::is_reference<key_type>::value, "");
// TODO(b/187807849): Evaluate whether to support reference mapped_type and
// remove this assertion if/when it is supported.
static_assert(!std::is_reference<mapped_type>::value, "");
using iterator = typename raw_hash_map::raw_hash_set::iterator;
using const_iterator = typename raw_hash_map::raw_hash_set::const_iterator;
raw_hash_map() {}
using raw_hash_map::raw_hash_set::raw_hash_set;
// The last two template parameters ensure that both arguments are rvalues
// (lvalue arguments are handled by the overloads below). This is necessary
// for supporting bitfield arguments.
//
// union { int n : 1; };
// flat_hash_map<int, int> m;
// m.insert_or_assign(n, n);
template <class K = key_type, class V = mapped_type, K* = nullptr,
V* = nullptr>
std::pair<iterator, bool> insert_or_assign(key_arg<K>&& k, V&& v)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_impl(std::forward<K>(k), std::forward<V>(v));
}
template <class K = key_type, class V = mapped_type, K* = nullptr>
std::pair<iterator, bool> insert_or_assign(key_arg<K>&& k, const V& v)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_impl(std::forward<K>(k), v);
}
template <class K = key_type, class V = mapped_type, V* = nullptr>
std::pair<iterator, bool> insert_or_assign(const key_arg<K>& k, V&& v)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_impl(k, std::forward<V>(v));
}
template <class K = key_type, class V = mapped_type>
std::pair<iterator, bool> insert_or_assign(const key_arg<K>& k, const V& v)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign_impl(k, v);
}
template <class K = key_type, class V = mapped_type, K* = nullptr,
V* = nullptr>
iterator insert_or_assign(const_iterator, key_arg<K>&& k,
V&& v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign(std::forward<K>(k), std::forward<V>(v)).first;
}
template <class K = key_type, class V = mapped_type, K* = nullptr>
iterator insert_or_assign(const_iterator, key_arg<K>&& k,
const V& v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign(std::forward<K>(k), v).first;
}
template <class K = key_type, class V = mapped_type, V* = nullptr>
iterator insert_or_assign(const_iterator, const key_arg<K>& k,
V&& v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign(k, std::forward<V>(v)).first;
}
template <class K = key_type, class V = mapped_type>
iterator insert_or_assign(const_iterator, const key_arg<K>& k,
const V& v) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return insert_or_assign(k, v).first;
}
// All `try_emplace()` overloads make the same guarantees regarding rvalue
// arguments as `std::unordered_map::try_emplace()`, namely that these
// functions will not move from rvalue arguments if insertions do not happen.
template <class K = key_type, class... Args,
typename std::enable_if<
!std::is_convertible<K, const_iterator>::value, int>::type = 0,
K* = nullptr>
std::pair<iterator, bool> try_emplace(key_arg<K>&& k, Args&&... args)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace_impl(std::forward<K>(k), std::forward<Args>(args)...);
}
template <class K = key_type, class... Args,
typename std::enable_if<
!std::is_convertible<K, const_iterator>::value, int>::type = 0>
std::pair<iterator, bool> try_emplace(const key_arg<K>& k, Args&&... args)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace_impl(k, std::forward<Args>(args)...);
}
template <class K = key_type, class... Args, K* = nullptr>
iterator try_emplace(const_iterator, key_arg<K>&& k,
Args&&... args) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace(std::forward<K>(k), std::forward<Args>(args)...).first;
}
template <class K = key_type, class... Args>
iterator try_emplace(const_iterator, const key_arg<K>& k,
Args&&... args) ABSL_ATTRIBUTE_LIFETIME_BOUND {
return try_emplace(k, std::forward<Args>(args)...).first;
}
template <class K = key_type, class P = Policy>
MappedReference<P> at(const key_arg<K>& key) ABSL_ATTRIBUTE_LIFETIME_BOUND {
auto it = this->find(key);
if (it == this->end()) {
base_internal::ThrowStdOutOfRange(
"absl::container_internal::raw_hash_map<>::at");
}
return Policy::value(&*it);
}
template <class K = key_type, class P = Policy>
MappedConstReference<P> at(const key_arg<K>& key) const
ABSL_ATTRIBUTE_LIFETIME_BOUND {
auto it = this->find(key);
if (it == this->end()) {
base_internal::ThrowStdOutOfRange(
"absl::container_internal::raw_hash_map<>::at");
}
return Policy::value(&*it);
}
template <class K = key_type, class P = Policy, K* = nullptr>
MappedReference<P> operator[](key_arg<K>&& key)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return Policy::value(&*try_emplace(std::forward<K>(key)).first);
}
template <class K = key_type, class P = Policy>
MappedReference<P> operator[](const key_arg<K>& key)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
return Policy::value(&*try_emplace(key).first);
}
private:
template <class K, class V>
std::pair<iterator, bool> insert_or_assign_impl(K&& k, V&& v)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
auto res = this->find_or_prepare_insert(k);
if (res.second)
this->emplace_at(res.first, std::forward<K>(k), std::forward<V>(v));
else
Policy::value(&*this->iterator_at(res.first)) = std::forward<V>(v);
return {this->iterator_at(res.first), res.second};
}
template <class K = key_type, class... Args>
std::pair<iterator, bool> try_emplace_impl(K&& k, Args&&... args)
ABSL_ATTRIBUTE_LIFETIME_BOUND {
auto res = this->find_or_prepare_insert(k);
if (res.second)
this->emplace_at(res.first, std::piecewise_construct,
std::forward_as_tuple(std::forward<K>(k)),
std::forward_as_tuple(std::forward<Args>(args)...));
return {this->iterator_at(res.first), res.second};
}
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_RAW_HASH_MAP_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_TEST_ALLOCATOR_H_
#define ABSL_CONTAINER_INTERNAL_TEST_ALLOCATOR_H_
#include <cassert>
#include <cstddef>
#include <cstdint>
#include <memory>
#include <type_traits>
#include "gtest/gtest.h"
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// This is a stateful allocator, but the state lives outside of the
// allocator (in whatever test is using the allocator). This is odd
// but helps in tests where the allocator is propagated into nested
// containers - that chain of allocators uses the same state and is
// thus easier to query for aggregate allocation information.
template <typename T>
class CountingAllocator {
public:
using Allocator = std::allocator<T>;
using AllocatorTraits = std::allocator_traits<Allocator>;
using value_type = typename AllocatorTraits::value_type;
using pointer = typename AllocatorTraits::pointer;
using const_pointer = typename AllocatorTraits::const_pointer;
using size_type = typename AllocatorTraits::size_type;
using difference_type = typename AllocatorTraits::difference_type;
CountingAllocator() = default;
explicit CountingAllocator(int64_t* bytes_used) : bytes_used_(bytes_used) {}
CountingAllocator(int64_t* bytes_used, int64_t* instance_count)
: bytes_used_(bytes_used), instance_count_(instance_count) {}
template <typename U>
CountingAllocator(const CountingAllocator<U>& x)
: bytes_used_(x.bytes_used_), instance_count_(x.instance_count_) {}
pointer allocate(
size_type n,
typename AllocatorTraits::const_void_pointer hint = nullptr) {
Allocator allocator;
pointer ptr = AllocatorTraits::allocate(allocator, n, hint);
if (bytes_used_ != nullptr) {
*bytes_used_ += n * sizeof(T);
}
return ptr;
}
void deallocate(pointer p, size_type n) {
Allocator allocator;
AllocatorTraits::deallocate(allocator, p, n);
if (bytes_used_ != nullptr) {
*bytes_used_ -= n * sizeof(T);
}
}
template <typename U, typename... Args>
void construct(U* p, Args&&... args) {
Allocator allocator;
AllocatorTraits::construct(allocator, p, std::forward<Args>(args)...);
if (instance_count_ != nullptr) {
*instance_count_ += 1;
}
}
template <typename U>
void destroy(U* p) {
Allocator allocator;
// Ignore GCC warning bug.
#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0)
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wuse-after-free"
#endif
AllocatorTraits::destroy(allocator, p);
#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0)
#pragma GCC diagnostic pop
#endif
if (instance_count_ != nullptr) {
*instance_count_ -= 1;
}
}
template <typename U>
class rebind {
public:
using other = CountingAllocator<U>;
};
friend bool operator==(const CountingAllocator& a,
const CountingAllocator& b) {
return a.bytes_used_ == b.bytes_used_ &&
a.instance_count_ == b.instance_count_;
}
friend bool operator!=(const CountingAllocator& a,
const CountingAllocator& b) {
return !(a == b);
}
int64_t* bytes_used_ = nullptr;
int64_t* instance_count_ = nullptr;
};
template <typename T>
struct CopyAssignPropagatingCountingAlloc : public CountingAllocator<T> {
using propagate_on_container_copy_assignment = std::true_type;
using Base = CountingAllocator<T>;
using Base::Base;
template <typename U>
explicit CopyAssignPropagatingCountingAlloc(
const CopyAssignPropagatingCountingAlloc<U>& other)
: Base(other.bytes_used_, other.instance_count_) {}
template <typename U>
struct rebind {
using other = CopyAssignPropagatingCountingAlloc<U>;
};
};
template <typename T>
struct MoveAssignPropagatingCountingAlloc : public CountingAllocator<T> {
using propagate_on_container_move_assignment = std::true_type;
using Base = CountingAllocator<T>;
using Base::Base;
template <typename U>
explicit MoveAssignPropagatingCountingAlloc(
const MoveAssignPropagatingCountingAlloc<U>& other)
: Base(other.bytes_used_, other.instance_count_) {}
template <typename U>
struct rebind {
using other = MoveAssignPropagatingCountingAlloc<U>;
};
};
template <typename T>
struct SwapPropagatingCountingAlloc : public CountingAllocator<T> {
using propagate_on_container_swap = std::true_type;
using Base = CountingAllocator<T>;
using Base::Base;
template <typename U>
explicit SwapPropagatingCountingAlloc(
const SwapPropagatingCountingAlloc<U>& other)
: Base(other.bytes_used_, other.instance_count_) {}
template <typename U>
struct rebind {
using other = SwapPropagatingCountingAlloc<U>;
};
};
// Tries to allocate memory at the minimum alignment even when the default
// allocator uses a higher alignment.
template <typename T>
struct MinimumAlignmentAlloc : std::allocator<T> {
MinimumAlignmentAlloc() = default;
template <typename U>
explicit MinimumAlignmentAlloc(const MinimumAlignmentAlloc<U>& /*other*/) {}
template <class U>
struct rebind {
using other = MinimumAlignmentAlloc<U>;
};
T* allocate(size_t n) {
T* ptr = std::allocator<T>::allocate(n + 1);
char* cptr = reinterpret_cast<char*>(ptr);
cptr += alignof(T);
return reinterpret_cast<T*>(cptr);
}
void deallocate(T* ptr, size_t n) {
char* cptr = reinterpret_cast<char*>(ptr);
cptr -= alignof(T);
std::allocator<T>::deallocate(reinterpret_cast<T*>(cptr), n + 1);
}
};
inline bool IsAssertEnabled() {
// Use an assert with side-effects to figure out if they are actually enabled.
bool assert_enabled = false;
assert([&]() { // NOLINT
assert_enabled = true;
return true;
}());
return assert_enabled;
}
template <template <class Alloc> class Container>
void TestCopyAssignAllocPropagation() {
int64_t bytes1 = 0, instances1 = 0, bytes2 = 0, instances2 = 0;
CopyAssignPropagatingCountingAlloc<int> allocator1(&bytes1, &instances1);
CopyAssignPropagatingCountingAlloc<int> allocator2(&bytes2, &instances2);
// Test propagating allocator_type.
{
Container<CopyAssignPropagatingCountingAlloc<int>> c1(allocator1);
Container<CopyAssignPropagatingCountingAlloc<int>> c2(allocator2);
for (int i = 0; i < 100; ++i) c1.insert(i);
EXPECT_NE(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
c2 = c1;
EXPECT_EQ(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 200);
EXPECT_EQ(instances2, 0);
}
// Test non-propagating allocator_type with different allocators.
{
Container<CountingAllocator<int>> c1(allocator1), c2(allocator2);
for (int i = 0; i < 100; ++i) c1.insert(i);
EXPECT_EQ(c2.get_allocator(), allocator2);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
c2 = c1;
EXPECT_EQ(c2.get_allocator(), allocator2);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 100);
}
EXPECT_EQ(bytes1, 0);
EXPECT_EQ(instances1, 0);
EXPECT_EQ(bytes2, 0);
EXPECT_EQ(instances2, 0);
}
template <template <class Alloc> class Container>
void TestMoveAssignAllocPropagation() {
int64_t bytes1 = 0, instances1 = 0, bytes2 = 0, instances2 = 0;
MoveAssignPropagatingCountingAlloc<int> allocator1(&bytes1, &instances1);
MoveAssignPropagatingCountingAlloc<int> allocator2(&bytes2, &instances2);
// Test propagating allocator_type.
{
Container<MoveAssignPropagatingCountingAlloc<int>> c1(allocator1);
Container<MoveAssignPropagatingCountingAlloc<int>> c2(allocator2);
for (int i = 0; i < 100; ++i) c1.insert(i);
EXPECT_NE(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
c2 = std::move(c1);
EXPECT_EQ(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
}
// Test non-propagating allocator_type with equal allocators.
{
Container<CountingAllocator<int>> c1(allocator1), c2(allocator1);
for (int i = 0; i < 100; ++i) c1.insert(i);
EXPECT_EQ(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
c2 = std::move(c1);
EXPECT_EQ(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
}
// Test non-propagating allocator_type with different allocators.
{
Container<CountingAllocator<int>> c1(allocator1), c2(allocator2);
for (int i = 0; i < 100; ++i) c1.insert(i);
EXPECT_NE(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
c2 = std::move(c1);
EXPECT_EQ(c2.get_allocator(), allocator2);
EXPECT_LE(instances1, 100); // The values in c1 may or may not have been
// destroyed at this point.
EXPECT_EQ(instances2, 100);
}
EXPECT_EQ(bytes1, 0);
EXPECT_EQ(instances1, 0);
EXPECT_EQ(bytes2, 0);
EXPECT_EQ(instances2, 0);
}
template <template <class Alloc> class Container>
void TestSwapAllocPropagation() {
int64_t bytes1 = 0, instances1 = 0, bytes2 = 0, instances2 = 0;
SwapPropagatingCountingAlloc<int> allocator1(&bytes1, &instances1);
SwapPropagatingCountingAlloc<int> allocator2(&bytes2, &instances2);
// Test propagating allocator_type.
{
Container<SwapPropagatingCountingAlloc<int>> c1(allocator1), c2(allocator2);
for (int i = 0; i < 100; ++i) c1.insert(i);
EXPECT_NE(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
c2.swap(c1);
EXPECT_EQ(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
}
// Test non-propagating allocator_type with equal allocators.
{
Container<CountingAllocator<int>> c1(allocator1), c2(allocator1);
for (int i = 0; i < 100; ++i) c1.insert(i);
EXPECT_EQ(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
c2.swap(c1);
EXPECT_EQ(c2.get_allocator(), allocator1);
EXPECT_EQ(instances1, 100);
EXPECT_EQ(instances2, 0);
}
// Test non-propagating allocator_type with different allocators.
{
Container<CountingAllocator<int>> c1(allocator1), c2(allocator2);
for (int i = 0; i < 100; ++i) c1.insert(i);
EXPECT_NE(c1.get_allocator(), c2.get_allocator());
if (IsAssertEnabled()) {
EXPECT_DEATH_IF_SUPPORTED(c2.swap(c1), "");
}
}
EXPECT_EQ(bytes1, 0);
EXPECT_EQ(instances1, 0);
EXPECT_EQ(bytes2, 0);
EXPECT_EQ(instances2, 0);
}
template <template <class Alloc> class Container>
void TestAllocPropagation() {
TestCopyAssignAllocPropagation<Container>();
TestMoveAssignAllocPropagation<Container>();
TestSwapAllocPropagation<Container>();
}
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_TEST_ALLOCATOR_H_

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_TEST_INSTANCE_TRACKER_H_
#define ABSL_CONTAINER_INTERNAL_TEST_INSTANCE_TRACKER_H_
#include <cstdlib>
#include <ostream>
#include "absl/types/compare.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace test_internal {
// A type that counts number of occurrences of the type, the live occurrences of
// the type, as well as the number of copies, moves, swaps, and comparisons that
// have occurred on the type. This is used as a base class for the copyable,
// copyable+movable, and movable types below that are used in actual tests. Use
// InstanceTracker in tests to track the number of instances.
class BaseCountedInstance {
public:
explicit BaseCountedInstance(int x) : value_(x) {
++num_instances_;
++num_live_instances_;
}
BaseCountedInstance(const BaseCountedInstance& x)
: value_(x.value_), is_live_(x.is_live_) {
++num_instances_;
if (is_live_) ++num_live_instances_;
++num_copies_;
}
BaseCountedInstance(BaseCountedInstance&& x)
: value_(x.value_), is_live_(x.is_live_) {
x.is_live_ = false;
++num_instances_;
++num_moves_;
}
~BaseCountedInstance() {
--num_instances_;
if (is_live_) --num_live_instances_;
}
BaseCountedInstance& operator=(const BaseCountedInstance& x) {
value_ = x.value_;
if (is_live_) --num_live_instances_;
is_live_ = x.is_live_;
if (is_live_) ++num_live_instances_;
++num_copies_;
return *this;
}
BaseCountedInstance& operator=(BaseCountedInstance&& x) {
value_ = x.value_;
if (is_live_) --num_live_instances_;
is_live_ = x.is_live_;
x.is_live_ = false;
++num_moves_;
return *this;
}
bool operator==(const BaseCountedInstance& x) const {
++num_comparisons_;
return value_ == x.value_;
}
bool operator!=(const BaseCountedInstance& x) const {
++num_comparisons_;
return value_ != x.value_;
}
bool operator<(const BaseCountedInstance& x) const {
++num_comparisons_;
return value_ < x.value_;
}
bool operator>(const BaseCountedInstance& x) const {
++num_comparisons_;
return value_ > x.value_;
}
bool operator<=(const BaseCountedInstance& x) const {
++num_comparisons_;
return value_ <= x.value_;
}
bool operator>=(const BaseCountedInstance& x) const {
++num_comparisons_;
return value_ >= x.value_;
}
absl::weak_ordering compare(const BaseCountedInstance& x) const {
++num_comparisons_;
return value_ < x.value_
? absl::weak_ordering::less
: value_ == x.value_ ? absl::weak_ordering::equivalent
: absl::weak_ordering::greater;
}
int value() const {
if (!is_live_) std::abort();
return value_;
}
friend std::ostream& operator<<(std::ostream& o,
const BaseCountedInstance& v) {
return o << "[value:" << v.value() << "]";
}
// Implementation of efficient swap() that counts swaps.
static void SwapImpl(
BaseCountedInstance& lhs, // NOLINT(runtime/references)
BaseCountedInstance& rhs) { // NOLINT(runtime/references)
using std::swap;
swap(lhs.value_, rhs.value_);
swap(lhs.is_live_, rhs.is_live_);
++BaseCountedInstance::num_swaps_;
}
private:
friend class InstanceTracker;
int value_;
// Indicates if the value is live, ie it hasn't been moved away from.
bool is_live_ = true;
// Number of instances.
static int num_instances_;
// Number of live instances (those that have not been moved away from.)
static int num_live_instances_;
// Number of times that BaseCountedInstance objects were moved.
static int num_moves_;
// Number of times that BaseCountedInstance objects were copied.
static int num_copies_;
// Number of times that BaseCountedInstance objects were swapped.
static int num_swaps_;
// Number of times that BaseCountedInstance objects were compared.
static int num_comparisons_;
};
// Helper to track the BaseCountedInstance instance counters. Expects that the
// number of instances and live_instances are the same when it is constructed
// and when it is destructed.
class InstanceTracker {
public:
InstanceTracker()
: start_instances_(BaseCountedInstance::num_instances_),
start_live_instances_(BaseCountedInstance::num_live_instances_) {
ResetCopiesMovesSwaps();
}
~InstanceTracker() {
if (instances() != 0) std::abort();
if (live_instances() != 0) std::abort();
}
// Returns the number of BaseCountedInstance instances both containing valid
// values and those moved away from compared to when the InstanceTracker was
// constructed
int instances() const {
return BaseCountedInstance::num_instances_ - start_instances_;
}
// Returns the number of live BaseCountedInstance instances compared to when
// the InstanceTracker was constructed
int live_instances() const {
return BaseCountedInstance::num_live_instances_ - start_live_instances_;
}
// Returns the number of moves on BaseCountedInstance objects since
// construction or since the last call to ResetCopiesMovesSwaps().
int moves() const { return BaseCountedInstance::num_moves_ - start_moves_; }
// Returns the number of copies on BaseCountedInstance objects since
// construction or the last call to ResetCopiesMovesSwaps().
int copies() const {
return BaseCountedInstance::num_copies_ - start_copies_;
}
// Returns the number of swaps on BaseCountedInstance objects since
// construction or the last call to ResetCopiesMovesSwaps().
int swaps() const { return BaseCountedInstance::num_swaps_ - start_swaps_; }
// Returns the number of comparisons on BaseCountedInstance objects since
// construction or the last call to ResetCopiesMovesSwaps().
int comparisons() const {
return BaseCountedInstance::num_comparisons_ - start_comparisons_;
}
// Resets the base values for moves, copies, comparisons, and swaps to the
// current values, so that subsequent Get*() calls for moves, copies,
// comparisons, and swaps will compare to the situation at the point of this
// call.
void ResetCopiesMovesSwaps() {
start_moves_ = BaseCountedInstance::num_moves_;
start_copies_ = BaseCountedInstance::num_copies_;
start_swaps_ = BaseCountedInstance::num_swaps_;
start_comparisons_ = BaseCountedInstance::num_comparisons_;
}
private:
int start_instances_;
int start_live_instances_;
int start_moves_;
int start_copies_;
int start_swaps_;
int start_comparisons_;
};
// Copyable, not movable.
class CopyableOnlyInstance : public BaseCountedInstance {
public:
explicit CopyableOnlyInstance(int x) : BaseCountedInstance(x) {}
CopyableOnlyInstance(const CopyableOnlyInstance& rhs) = default;
CopyableOnlyInstance& operator=(const CopyableOnlyInstance& rhs) = default;
friend void swap(CopyableOnlyInstance& lhs, CopyableOnlyInstance& rhs) {
BaseCountedInstance::SwapImpl(lhs, rhs);
}
static bool supports_move() { return false; }
};
// Copyable and movable.
class CopyableMovableInstance : public BaseCountedInstance {
public:
explicit CopyableMovableInstance(int x) : BaseCountedInstance(x) {}
CopyableMovableInstance(const CopyableMovableInstance& rhs) = default;
CopyableMovableInstance(CopyableMovableInstance&& rhs) = default;
CopyableMovableInstance& operator=(const CopyableMovableInstance& rhs) =
default;
CopyableMovableInstance& operator=(CopyableMovableInstance&& rhs) = default;
friend void swap(CopyableMovableInstance& lhs, CopyableMovableInstance& rhs) {
BaseCountedInstance::SwapImpl(lhs, rhs);
}
static bool supports_move() { return true; }
};
// Only movable, not default-constructible.
class MovableOnlyInstance : public BaseCountedInstance {
public:
explicit MovableOnlyInstance(int x) : BaseCountedInstance(x) {}
MovableOnlyInstance(MovableOnlyInstance&& other) = default;
MovableOnlyInstance& operator=(MovableOnlyInstance&& other) = default;
friend void swap(MovableOnlyInstance& lhs, MovableOnlyInstance& rhs) {
BaseCountedInstance::SwapImpl(lhs, rhs);
}
static bool supports_move() { return true; }
};
} // namespace test_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_TEST_INSTANCE_TRACKER_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_TRACKED_H_
#define ABSL_CONTAINER_INTERNAL_TRACKED_H_
#include <stddef.h>
#include <memory>
#include <utility>
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// A class that tracks its copies and moves so that it can be queried in tests.
template <class T>
class Tracked {
public:
Tracked() {}
// NOLINTNEXTLINE(runtime/explicit)
Tracked(const T& val) : val_(val) {}
Tracked(const Tracked& that)
: val_(that.val_),
num_moves_(that.num_moves_),
num_copies_(that.num_copies_) {
++(*num_copies_);
}
Tracked(Tracked&& that)
: val_(std::move(that.val_)),
num_moves_(std::move(that.num_moves_)),
num_copies_(std::move(that.num_copies_)) {
++(*num_moves_);
}
Tracked& operator=(const Tracked& that) {
val_ = that.val_;
num_moves_ = that.num_moves_;
num_copies_ = that.num_copies_;
++(*num_copies_);
}
Tracked& operator=(Tracked&& that) {
val_ = std::move(that.val_);
num_moves_ = std::move(that.num_moves_);
num_copies_ = std::move(that.num_copies_);
++(*num_moves_);
}
const T& val() const { return val_; }
friend bool operator==(const Tracked& a, const Tracked& b) {
return a.val_ == b.val_;
}
friend bool operator!=(const Tracked& a, const Tracked& b) {
return !(a == b);
}
size_t num_copies() { return *num_copies_; }
size_t num_moves() { return *num_moves_; }
private:
T val_;
std::shared_ptr<size_t> num_moves_ = std::make_shared<size_t>(0);
std::shared_ptr<size_t> num_copies_ = std::make_shared<size_t>(0);
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_TRACKED_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_CONSTRUCTOR_TEST_H_
#define ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_CONSTRUCTOR_TEST_H_
#include <algorithm>
#include <unordered_map>
#include <vector>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/container/internal/hash_generator_testing.h"
#include "absl/container/internal/hash_policy_testing.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class UnordMap>
class ConstructorTest : public ::testing::Test {};
TYPED_TEST_SUITE_P(ConstructorTest);
TYPED_TEST_P(ConstructorTest, NoArgs) {
TypeParam m;
EXPECT_TRUE(m.empty());
EXPECT_THAT(m, ::testing::UnorderedElementsAre());
}
TYPED_TEST_P(ConstructorTest, BucketCount) {
TypeParam m(123);
EXPECT_TRUE(m.empty());
EXPECT_THAT(m, ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountHash) {
using H = typename TypeParam::hasher;
H hasher;
TypeParam m(123, hasher);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_TRUE(m.empty());
EXPECT_THAT(m, ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountHashEqual) {
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
H hasher;
E equal;
TypeParam m(123, hasher, equal);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.key_eq(), equal);
EXPECT_TRUE(m.empty());
EXPECT_THAT(m, ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountHashEqualAlloc) {
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
TypeParam m(123, hasher, equal, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.key_eq(), equal);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_TRUE(m.empty());
EXPECT_THAT(m, ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
template <typename T>
struct is_std_unordered_map : std::false_type {};
template <typename... T>
struct is_std_unordered_map<std::unordered_map<T...>> : std::true_type {};
#if defined(UNORDERED_MAP_CXX14) || defined(UNORDERED_MAP_CXX17)
using has_cxx14_std_apis = std::true_type;
#else
using has_cxx14_std_apis = std::false_type;
#endif
template <typename T>
using expect_cxx14_apis =
absl::disjunction<absl::negation<is_std_unordered_map<T>>,
has_cxx14_std_apis>;
template <typename TypeParam>
void BucketCountAllocTest(std::false_type) {}
template <typename TypeParam>
void BucketCountAllocTest(std::true_type) {
using A = typename TypeParam::allocator_type;
A alloc(0);
TypeParam m(123, alloc);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_TRUE(m.empty());
EXPECT_THAT(m, ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountAlloc) {
BucketCountAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
template <typename TypeParam>
void BucketCountHashAllocTest(std::false_type) {}
template <typename TypeParam>
void BucketCountHashAllocTest(std::true_type) {
using H = typename TypeParam::hasher;
using A = typename TypeParam::allocator_type;
H hasher;
A alloc(0);
TypeParam m(123, hasher, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_TRUE(m.empty());
EXPECT_THAT(m, ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountHashAlloc) {
BucketCountHashAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
#if ABSL_UNORDERED_SUPPORTS_ALLOC_CTORS
using has_alloc_std_constructors = std::true_type;
#else
using has_alloc_std_constructors = std::false_type;
#endif
template <typename T>
using expect_alloc_constructors =
absl::disjunction<absl::negation<is_std_unordered_map<T>>,
has_alloc_std_constructors>;
template <typename TypeParam>
void AllocTest(std::false_type) {}
template <typename TypeParam>
void AllocTest(std::true_type) {
using A = typename TypeParam::allocator_type;
A alloc(0);
TypeParam m(alloc);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_TRUE(m.empty());
EXPECT_THAT(m, ::testing::UnorderedElementsAre());
}
TYPED_TEST_P(ConstructorTest, Alloc) {
AllocTest<TypeParam>(expect_alloc_constructors<TypeParam>());
}
TYPED_TEST_P(ConstructorTest, InputIteratorBucketHashEqualAlloc) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::UniqueGenerator<T>());
TypeParam m(values.begin(), values.end(), 123, hasher, equal, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.key_eq(), equal);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
template <typename TypeParam>
void InputIteratorBucketAllocTest(std::false_type) {}
template <typename TypeParam>
void InputIteratorBucketAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using A = typename TypeParam::allocator_type;
A alloc(0);
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::UniqueGenerator<T>());
TypeParam m(values.begin(), values.end(), 123, alloc);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, InputIteratorBucketAlloc) {
InputIteratorBucketAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
template <typename TypeParam>
void InputIteratorBucketHashAllocTest(std::false_type) {}
template <typename TypeParam>
void InputIteratorBucketHashAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using A = typename TypeParam::allocator_type;
H hasher;
A alloc(0);
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::UniqueGenerator<T>());
TypeParam m(values.begin(), values.end(), 123, hasher, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, InputIteratorBucketHashAlloc) {
InputIteratorBucketHashAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
TYPED_TEST_P(ConstructorTest, CopyConstructor) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
hash_internal::UniqueGenerator<T> gen;
TypeParam m(123, hasher, equal, alloc);
for (size_t i = 0; i != 10; ++i) m.insert(gen());
TypeParam n(m);
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_EQ(m.get_allocator(), n.get_allocator());
EXPECT_EQ(m, n);
}
template <typename TypeParam>
void CopyConstructorAllocTest(std::false_type) {}
template <typename TypeParam>
void CopyConstructorAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
hash_internal::UniqueGenerator<T> gen;
TypeParam m(123, hasher, equal, alloc);
for (size_t i = 0; i != 10; ++i) m.insert(gen());
TypeParam n(m, A(11));
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_NE(m.get_allocator(), n.get_allocator());
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, CopyConstructorAlloc) {
CopyConstructorAllocTest<TypeParam>(expect_alloc_constructors<TypeParam>());
}
// TODO(alkis): Test non-propagating allocators on copy constructors.
TYPED_TEST_P(ConstructorTest, MoveConstructor) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
hash_internal::UniqueGenerator<T> gen;
TypeParam m(123, hasher, equal, alloc);
for (size_t i = 0; i != 10; ++i) m.insert(gen());
TypeParam t(m);
TypeParam n(std::move(t));
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_EQ(m.get_allocator(), n.get_allocator());
EXPECT_EQ(m, n);
}
template <typename TypeParam>
void MoveConstructorAllocTest(std::false_type) {}
template <typename TypeParam>
void MoveConstructorAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
hash_internal::UniqueGenerator<T> gen;
TypeParam m(123, hasher, equal, alloc);
for (size_t i = 0; i != 10; ++i) m.insert(gen());
TypeParam t(m);
TypeParam n(std::move(t), A(1));
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_NE(m.get_allocator(), n.get_allocator());
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, MoveConstructorAlloc) {
MoveConstructorAllocTest<TypeParam>(expect_alloc_constructors<TypeParam>());
}
// TODO(alkis): Test non-propagating allocators on move constructors.
TYPED_TEST_P(ConstructorTest, InitializerListBucketHashEqualAlloc) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::UniqueGenerator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
TypeParam m(values, 123, hasher, equal, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.key_eq(), equal);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
template <typename TypeParam>
void InitializerListBucketAllocTest(std::false_type) {}
template <typename TypeParam>
void InitializerListBucketAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using A = typename TypeParam::allocator_type;
hash_internal::UniqueGenerator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
A alloc(0);
TypeParam m(values, 123, alloc);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, InitializerListBucketAlloc) {
InitializerListBucketAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
template <typename TypeParam>
void InitializerListBucketHashAllocTest(std::false_type) {}
template <typename TypeParam>
void InitializerListBucketHashAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using A = typename TypeParam::allocator_type;
H hasher;
A alloc(0);
hash_internal::UniqueGenerator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
TypeParam m(values, 123, hasher, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, InitializerListBucketHashAlloc) {
InitializerListBucketHashAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
TYPED_TEST_P(ConstructorTest, Assignment) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
hash_internal::UniqueGenerator<T> gen;
TypeParam m({gen(), gen(), gen()}, 123, hasher, equal, alloc);
TypeParam n;
n = m;
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_EQ(m, n);
}
// TODO(alkis): Test [non-]propagating allocators on move/copy assignments
// (it depends on traits).
TYPED_TEST_P(ConstructorTest, MoveAssignment) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
hash_internal::UniqueGenerator<T> gen;
TypeParam m({gen(), gen(), gen()}, 123, hasher, equal, alloc);
TypeParam t(m);
TypeParam n;
n = std::move(t);
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, AssignmentFromInitializerList) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::UniqueGenerator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
TypeParam m;
m = values;
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
}
TYPED_TEST_P(ConstructorTest, AssignmentOverwritesExisting) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::UniqueGenerator<T> gen;
TypeParam m({gen(), gen(), gen()});
TypeParam n({gen()});
n = m;
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, MoveAssignmentOverwritesExisting) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::UniqueGenerator<T> gen;
TypeParam m({gen(), gen(), gen()});
TypeParam t(m);
TypeParam n({gen()});
n = std::move(t);
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, AssignmentFromInitializerListOverwritesExisting) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::UniqueGenerator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
TypeParam m;
m = values;
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
}
TYPED_TEST_P(ConstructorTest, AssignmentOnSelf) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::UniqueGenerator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
TypeParam m(values);
m = *&m; // Avoid -Wself-assign
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
}
// We cannot test self move as standard states that it leaves standard
// containers in unspecified state (and in practice in causes memory-leak
// according to heap-checker!).
REGISTER_TYPED_TEST_SUITE_P(
ConstructorTest, NoArgs, BucketCount, BucketCountHash, BucketCountHashEqual,
BucketCountHashEqualAlloc, BucketCountAlloc, BucketCountHashAlloc, Alloc,
InputIteratorBucketHashEqualAlloc, InputIteratorBucketAlloc,
InputIteratorBucketHashAlloc, CopyConstructor, CopyConstructorAlloc,
MoveConstructor, MoveConstructorAlloc, InitializerListBucketHashEqualAlloc,
InitializerListBucketAlloc, InitializerListBucketHashAlloc, Assignment,
MoveAssignment, AssignmentFromInitializerList, AssignmentOverwritesExisting,
MoveAssignmentOverwritesExisting,
AssignmentFromInitializerListOverwritesExisting, AssignmentOnSelf);
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_CONSTRUCTOR_TEST_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_LOOKUP_TEST_H_
#define ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_LOOKUP_TEST_H_
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/container/internal/hash_generator_testing.h"
#include "absl/container/internal/hash_policy_testing.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class UnordMap>
class LookupTest : public ::testing::Test {};
TYPED_TEST_SUITE_P(LookupTest);
TYPED_TEST_P(LookupTest, At) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m(values.begin(), values.end());
for (const auto& p : values) {
const auto& val = m.at(p.first);
EXPECT_EQ(p.second, val) << ::testing::PrintToString(p.first);
}
}
TYPED_TEST_P(LookupTest, OperatorBracket) {
using T = hash_internal::GeneratedType<TypeParam>;
using V = typename TypeParam::mapped_type;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m;
for (const auto& p : values) {
auto& val = m[p.first];
EXPECT_EQ(V(), val) << ::testing::PrintToString(p.first);
val = p.second;
}
for (const auto& p : values)
EXPECT_EQ(p.second, m[p.first]) << ::testing::PrintToString(p.first);
}
TYPED_TEST_P(LookupTest, Count) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m;
for (const auto& p : values)
EXPECT_EQ(0, m.count(p.first)) << ::testing::PrintToString(p.first);
m.insert(values.begin(), values.end());
for (const auto& p : values)
EXPECT_EQ(1, m.count(p.first)) << ::testing::PrintToString(p.first);
}
TYPED_TEST_P(LookupTest, Find) {
using std::get;
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m;
for (const auto& p : values)
EXPECT_TRUE(m.end() == m.find(p.first))
<< ::testing::PrintToString(p.first);
m.insert(values.begin(), values.end());
for (const auto& p : values) {
auto it = m.find(p.first);
EXPECT_TRUE(m.end() != it) << ::testing::PrintToString(p.first);
EXPECT_EQ(p.second, get<1>(*it)) << ::testing::PrintToString(p.first);
}
}
TYPED_TEST_P(LookupTest, EqualRange) {
using std::get;
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m;
for (const auto& p : values) {
auto r = m.equal_range(p.first);
ASSERT_EQ(0, std::distance(r.first, r.second));
}
m.insert(values.begin(), values.end());
for (const auto& p : values) {
auto r = m.equal_range(p.first);
ASSERT_EQ(1, std::distance(r.first, r.second));
EXPECT_EQ(p.second, get<1>(*r.first)) << ::testing::PrintToString(p.first);
}
}
REGISTER_TYPED_TEST_SUITE_P(LookupTest, At, OperatorBracket, Count, Find,
EqualRange);
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_LOOKUP_TEST_H_

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// Copyright 2019 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_MEMBERS_TEST_H_
#define ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_MEMBERS_TEST_H_
#include <type_traits>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/meta/type_traits.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class UnordMap>
class MembersTest : public ::testing::Test {};
TYPED_TEST_SUITE_P(MembersTest);
template <typename T>
void UseType() {}
TYPED_TEST_P(MembersTest, Typedefs) {
EXPECT_TRUE((std::is_same<std::pair<const typename TypeParam::key_type,
typename TypeParam::mapped_type>,
typename TypeParam::value_type>()));
EXPECT_TRUE((absl::conjunction<
absl::negation<std::is_signed<typename TypeParam::size_type>>,
std::is_integral<typename TypeParam::size_type>>()));
EXPECT_TRUE((absl::conjunction<
std::is_signed<typename TypeParam::difference_type>,
std::is_integral<typename TypeParam::difference_type>>()));
EXPECT_TRUE((std::is_convertible<
decltype(std::declval<const typename TypeParam::hasher&>()(
std::declval<const typename TypeParam::key_type&>())),
size_t>()));
EXPECT_TRUE((std::is_convertible<
decltype(std::declval<const typename TypeParam::key_equal&>()(
std::declval<const typename TypeParam::key_type&>(),
std::declval<const typename TypeParam::key_type&>())),
bool>()));
EXPECT_TRUE((std::is_same<typename TypeParam::allocator_type::value_type,
typename TypeParam::value_type>()));
EXPECT_TRUE((std::is_same<typename TypeParam::value_type&,
typename TypeParam::reference>()));
EXPECT_TRUE((std::is_same<const typename TypeParam::value_type&,
typename TypeParam::const_reference>()));
EXPECT_TRUE((std::is_same<typename std::allocator_traits<
typename TypeParam::allocator_type>::pointer,
typename TypeParam::pointer>()));
EXPECT_TRUE(
(std::is_same<typename std::allocator_traits<
typename TypeParam::allocator_type>::const_pointer,
typename TypeParam::const_pointer>()));
}
TYPED_TEST_P(MembersTest, SimpleFunctions) {
EXPECT_GT(TypeParam().max_size(), 0);
}
TYPED_TEST_P(MembersTest, BeginEnd) {
TypeParam t = {typename TypeParam::value_type{}};
EXPECT_EQ(t.begin(), t.cbegin());
EXPECT_EQ(t.end(), t.cend());
EXPECT_NE(t.begin(), t.end());
EXPECT_NE(t.cbegin(), t.cend());
}
REGISTER_TYPED_TEST_SUITE_P(MembersTest, Typedefs, SimpleFunctions, BeginEnd);
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_MEMBERS_TEST_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_MODIFIERS_TEST_H_
#define ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_MODIFIERS_TEST_H_
#include <memory>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/container/internal/hash_generator_testing.h"
#include "absl/container/internal/hash_policy_testing.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class UnordMap>
class ModifiersTest : public ::testing::Test {};
TYPED_TEST_SUITE_P(ModifiersTest);
TYPED_TEST_P(ModifiersTest, Clear) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m(values.begin(), values.end());
ASSERT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
m.clear();
EXPECT_THAT(items(m), ::testing::UnorderedElementsAre());
EXPECT_TRUE(m.empty());
}
TYPED_TEST_P(ModifiersTest, Insert) {
using T = hash_internal::GeneratedType<TypeParam>;
using V = typename TypeParam::mapped_type;
T val = hash_internal::Generator<T>()();
TypeParam m;
auto p = m.insert(val);
EXPECT_TRUE(p.second);
EXPECT_EQ(val, *p.first);
T val2 = {val.first, hash_internal::Generator<V>()()};
p = m.insert(val2);
EXPECT_FALSE(p.second);
EXPECT_EQ(val, *p.first);
}
TYPED_TEST_P(ModifiersTest, InsertHint) {
using T = hash_internal::GeneratedType<TypeParam>;
using V = typename TypeParam::mapped_type;
T val = hash_internal::Generator<T>()();
TypeParam m;
auto it = m.insert(m.end(), val);
EXPECT_TRUE(it != m.end());
EXPECT_EQ(val, *it);
T val2 = {val.first, hash_internal::Generator<V>()()};
it = m.insert(it, val2);
EXPECT_TRUE(it != m.end());
EXPECT_EQ(val, *it);
}
TYPED_TEST_P(ModifiersTest, InsertRange) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m;
m.insert(values.begin(), values.end());
ASSERT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
}
TYPED_TEST_P(ModifiersTest, InsertWithinCapacity) {
using T = hash_internal::GeneratedType<TypeParam>;
using V = typename TypeParam::mapped_type;
T val = hash_internal::Generator<T>()();
TypeParam m;
m.reserve(10);
const size_t original_capacity = m.bucket_count();
m.insert(val);
EXPECT_EQ(m.bucket_count(), original_capacity);
T val2 = {val.first, hash_internal::Generator<V>()()};
m.insert(val2);
EXPECT_EQ(m.bucket_count(), original_capacity);
}
TYPED_TEST_P(ModifiersTest, InsertRangeWithinCapacity) {
#if !defined(__GLIBCXX__)
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> base_values;
std::generate_n(std::back_inserter(base_values), 10,
hash_internal::Generator<T>());
std::vector<T> values;
while (values.size() != 100) {
std::copy_n(base_values.begin(), 10, std::back_inserter(values));
}
TypeParam m;
m.reserve(10);
const size_t original_capacity = m.bucket_count();
m.insert(values.begin(), values.end());
EXPECT_EQ(m.bucket_count(), original_capacity);
#endif
}
TYPED_TEST_P(ModifiersTest, InsertOrAssign) {
#ifdef UNORDERED_MAP_CXX17
using std::get;
using K = typename TypeParam::key_type;
using V = typename TypeParam::mapped_type;
K k = hash_internal::Generator<K>()();
V val = hash_internal::Generator<V>()();
TypeParam m;
auto p = m.insert_or_assign(k, val);
EXPECT_TRUE(p.second);
EXPECT_EQ(k, get<0>(*p.first));
EXPECT_EQ(val, get<1>(*p.first));
V val2 = hash_internal::Generator<V>()();
p = m.insert_or_assign(k, val2);
EXPECT_FALSE(p.second);
EXPECT_EQ(k, get<0>(*p.first));
EXPECT_EQ(val2, get<1>(*p.first));
#endif
}
TYPED_TEST_P(ModifiersTest, InsertOrAssignHint) {
#ifdef UNORDERED_MAP_CXX17
using std::get;
using K = typename TypeParam::key_type;
using V = typename TypeParam::mapped_type;
K k = hash_internal::Generator<K>()();
V val = hash_internal::Generator<V>()();
TypeParam m;
auto it = m.insert_or_assign(m.end(), k, val);
EXPECT_TRUE(it != m.end());
EXPECT_EQ(k, get<0>(*it));
EXPECT_EQ(val, get<1>(*it));
V val2 = hash_internal::Generator<V>()();
it = m.insert_or_assign(it, k, val2);
EXPECT_EQ(k, get<0>(*it));
EXPECT_EQ(val2, get<1>(*it));
#endif
}
TYPED_TEST_P(ModifiersTest, Emplace) {
using T = hash_internal::GeneratedType<TypeParam>;
using V = typename TypeParam::mapped_type;
T val = hash_internal::Generator<T>()();
TypeParam m;
// TODO(alkis): We need a way to run emplace in a more meaningful way. Perhaps
// with test traits/policy.
auto p = m.emplace(val);
EXPECT_TRUE(p.second);
EXPECT_EQ(val, *p.first);
T val2 = {val.first, hash_internal::Generator<V>()()};
p = m.emplace(val2);
EXPECT_FALSE(p.second);
EXPECT_EQ(val, *p.first);
}
TYPED_TEST_P(ModifiersTest, EmplaceHint) {
using T = hash_internal::GeneratedType<TypeParam>;
using V = typename TypeParam::mapped_type;
T val = hash_internal::Generator<T>()();
TypeParam m;
// TODO(alkis): We need a way to run emplace in a more meaningful way. Perhaps
// with test traits/policy.
auto it = m.emplace_hint(m.end(), val);
EXPECT_EQ(val, *it);
T val2 = {val.first, hash_internal::Generator<V>()()};
it = m.emplace_hint(it, val2);
EXPECT_EQ(val, *it);
}
TYPED_TEST_P(ModifiersTest, TryEmplace) {
#ifdef UNORDERED_MAP_CXX17
using T = hash_internal::GeneratedType<TypeParam>;
using V = typename TypeParam::mapped_type;
T val = hash_internal::Generator<T>()();
TypeParam m;
// TODO(alkis): We need a way to run emplace in a more meaningful way. Perhaps
// with test traits/policy.
auto p = m.try_emplace(val.first, val.second);
EXPECT_TRUE(p.second);
EXPECT_EQ(val, *p.first);
T val2 = {val.first, hash_internal::Generator<V>()()};
p = m.try_emplace(val2.first, val2.second);
EXPECT_FALSE(p.second);
EXPECT_EQ(val, *p.first);
#endif
}
TYPED_TEST_P(ModifiersTest, TryEmplaceHint) {
#ifdef UNORDERED_MAP_CXX17
using T = hash_internal::GeneratedType<TypeParam>;
using V = typename TypeParam::mapped_type;
T val = hash_internal::Generator<T>()();
TypeParam m;
// TODO(alkis): We need a way to run emplace in a more meaningful way. Perhaps
// with test traits/policy.
auto it = m.try_emplace(m.end(), val.first, val.second);
EXPECT_EQ(val, *it);
T val2 = {val.first, hash_internal::Generator<V>()()};
it = m.try_emplace(it, val2.first, val2.second);
EXPECT_EQ(val, *it);
#endif
}
template <class V>
using IfNotVoid = typename std::enable_if<!std::is_void<V>::value, V>::type;
// In openmap we chose not to return the iterator from erase because that's
// more expensive. As such we adapt erase to return an iterator here.
struct EraseFirst {
template <class Map>
auto operator()(Map* m, int) const
-> IfNotVoid<decltype(m->erase(m->begin()))> {
return m->erase(m->begin());
}
template <class Map>
typename Map::iterator operator()(Map* m, ...) const {
auto it = m->begin();
m->erase(it++);
return it;
}
};
TYPED_TEST_P(ModifiersTest, Erase) {
using T = hash_internal::GeneratedType<TypeParam>;
using std::get;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m(values.begin(), values.end());
ASSERT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
auto& first = *m.begin();
std::vector<T> values2;
for (const auto& val : values)
if (get<0>(val) != get<0>(first)) values2.push_back(val);
auto it = EraseFirst()(&m, 0);
ASSERT_TRUE(it != m.end());
EXPECT_EQ(1, std::count(values2.begin(), values2.end(), *it));
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values2.begin(),
values2.end()));
}
TYPED_TEST_P(ModifiersTest, EraseRange) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m(values.begin(), values.end());
ASSERT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
auto it = m.erase(m.begin(), m.end());
EXPECT_THAT(items(m), ::testing::UnorderedElementsAre());
EXPECT_TRUE(it == m.end());
}
TYPED_TEST_P(ModifiersTest, EraseKey) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m(values.begin(), values.end());
ASSERT_THAT(items(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_EQ(1, m.erase(values[0].first));
EXPECT_EQ(0, std::count(m.begin(), m.end(), values[0]));
EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values.begin() + 1,
values.end()));
}
TYPED_TEST_P(ModifiersTest, Swap) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> v1;
std::vector<T> v2;
std::generate_n(std::back_inserter(v1), 5, hash_internal::Generator<T>());
std::generate_n(std::back_inserter(v2), 5, hash_internal::Generator<T>());
TypeParam m1(v1.begin(), v1.end());
TypeParam m2(v2.begin(), v2.end());
EXPECT_THAT(items(m1), ::testing::UnorderedElementsAreArray(v1));
EXPECT_THAT(items(m2), ::testing::UnorderedElementsAreArray(v2));
m1.swap(m2);
EXPECT_THAT(items(m1), ::testing::UnorderedElementsAreArray(v2));
EXPECT_THAT(items(m2), ::testing::UnorderedElementsAreArray(v1));
}
// TODO(alkis): Write tests for extract.
// TODO(alkis): Write tests for merge.
REGISTER_TYPED_TEST_SUITE_P(ModifiersTest, Clear, Insert, InsertHint,
InsertRange, InsertWithinCapacity,
InsertRangeWithinCapacity, InsertOrAssign,
InsertOrAssignHint, Emplace, EmplaceHint,
TryEmplace, TryEmplaceHint, Erase, EraseRange,
EraseKey, Swap);
template <typename Type>
struct is_unique_ptr : std::false_type {};
template <typename Type>
struct is_unique_ptr<std::unique_ptr<Type>> : std::true_type {};
template <class UnordMap>
class UniquePtrModifiersTest : public ::testing::Test {
protected:
UniquePtrModifiersTest() {
static_assert(is_unique_ptr<typename UnordMap::mapped_type>::value,
"UniquePtrModifiersTyest may only be called with a "
"std::unique_ptr value type.");
}
};
GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(UniquePtrModifiersTest);
TYPED_TEST_SUITE_P(UniquePtrModifiersTest);
// Test that we do not move from rvalue arguments if an insertion does not
// happen.
TYPED_TEST_P(UniquePtrModifiersTest, TryEmplace) {
#ifdef UNORDERED_MAP_CXX17
using T = hash_internal::GeneratedType<TypeParam>;
using V = typename TypeParam::mapped_type;
T val = hash_internal::Generator<T>()();
TypeParam m;
auto p = m.try_emplace(val.first, std::move(val.second));
EXPECT_TRUE(p.second);
// A moved from std::unique_ptr is guaranteed to be nullptr.
EXPECT_EQ(val.second, nullptr);
T val2 = {val.first, hash_internal::Generator<V>()()};
p = m.try_emplace(val2.first, std::move(val2.second));
EXPECT_FALSE(p.second);
EXPECT_NE(val2.second, nullptr);
#endif
}
REGISTER_TYPED_TEST_SUITE_P(UniquePtrModifiersTest, TryEmplace);
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_MODIFIERS_TEST_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_UNORDERED_SET_CONSTRUCTOR_TEST_H_
#define ABSL_CONTAINER_INTERNAL_UNORDERED_SET_CONSTRUCTOR_TEST_H_
#include <algorithm>
#include <unordered_set>
#include <vector>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/container/internal/hash_generator_testing.h"
#include "absl/container/internal/hash_policy_testing.h"
#include "absl/meta/type_traits.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class UnordMap>
class ConstructorTest : public ::testing::Test {};
TYPED_TEST_SUITE_P(ConstructorTest);
TYPED_TEST_P(ConstructorTest, NoArgs) {
TypeParam m;
EXPECT_TRUE(m.empty());
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
}
TYPED_TEST_P(ConstructorTest, BucketCount) {
TypeParam m(123);
EXPECT_TRUE(m.empty());
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountHash) {
using H = typename TypeParam::hasher;
H hasher;
TypeParam m(123, hasher);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_TRUE(m.empty());
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountHashEqual) {
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
H hasher;
E equal;
TypeParam m(123, hasher, equal);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.key_eq(), equal);
EXPECT_TRUE(m.empty());
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountHashEqualAlloc) {
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
TypeParam m(123, hasher, equal, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.key_eq(), equal);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_TRUE(m.empty());
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
const auto& cm = m;
EXPECT_EQ(cm.hash_function(), hasher);
EXPECT_EQ(cm.key_eq(), equal);
EXPECT_EQ(cm.get_allocator(), alloc);
EXPECT_TRUE(cm.empty());
EXPECT_THAT(keys(cm), ::testing::UnorderedElementsAre());
EXPECT_GE(cm.bucket_count(), 123);
}
template <typename T>
struct is_std_unordered_set : std::false_type {};
template <typename... T>
struct is_std_unordered_set<std::unordered_set<T...>> : std::true_type {};
#if defined(UNORDERED_SET_CXX14) || defined(UNORDERED_SET_CXX17)
using has_cxx14_std_apis = std::true_type;
#else
using has_cxx14_std_apis = std::false_type;
#endif
template <typename T>
using expect_cxx14_apis =
absl::disjunction<absl::negation<is_std_unordered_set<T>>,
has_cxx14_std_apis>;
template <typename TypeParam>
void BucketCountAllocTest(std::false_type) {}
template <typename TypeParam>
void BucketCountAllocTest(std::true_type) {
using A = typename TypeParam::allocator_type;
A alloc(0);
TypeParam m(123, alloc);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_TRUE(m.empty());
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountAlloc) {
BucketCountAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
template <typename TypeParam>
void BucketCountHashAllocTest(std::false_type) {}
template <typename TypeParam>
void BucketCountHashAllocTest(std::true_type) {
using H = typename TypeParam::hasher;
using A = typename TypeParam::allocator_type;
H hasher;
A alloc(0);
TypeParam m(123, hasher, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_TRUE(m.empty());
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, BucketCountHashAlloc) {
BucketCountHashAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
#if ABSL_UNORDERED_SUPPORTS_ALLOC_CTORS
using has_alloc_std_constructors = std::true_type;
#else
using has_alloc_std_constructors = std::false_type;
#endif
template <typename T>
using expect_alloc_constructors =
absl::disjunction<absl::negation<is_std_unordered_set<T>>,
has_alloc_std_constructors>;
template <typename TypeParam>
void AllocTest(std::false_type) {}
template <typename TypeParam>
void AllocTest(std::true_type) {
using A = typename TypeParam::allocator_type;
A alloc(0);
TypeParam m(alloc);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_TRUE(m.empty());
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
}
TYPED_TEST_P(ConstructorTest, Alloc) {
AllocTest<TypeParam>(expect_alloc_constructors<TypeParam>());
}
TYPED_TEST_P(ConstructorTest, InputIteratorBucketHashEqualAlloc) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
std::vector<T> values;
for (size_t i = 0; i != 10; ++i)
values.push_back(hash_internal::Generator<T>()());
TypeParam m(values.begin(), values.end(), 123, hasher, equal, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.key_eq(), equal);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
template <typename TypeParam>
void InputIteratorBucketAllocTest(std::false_type) {}
template <typename TypeParam>
void InputIteratorBucketAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using A = typename TypeParam::allocator_type;
A alloc(0);
std::vector<T> values;
for (size_t i = 0; i != 10; ++i)
values.push_back(hash_internal::Generator<T>()());
TypeParam m(values.begin(), values.end(), 123, alloc);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, InputIteratorBucketAlloc) {
InputIteratorBucketAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
template <typename TypeParam>
void InputIteratorBucketHashAllocTest(std::false_type) {}
template <typename TypeParam>
void InputIteratorBucketHashAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using A = typename TypeParam::allocator_type;
H hasher;
A alloc(0);
std::vector<T> values;
for (size_t i = 0; i != 10; ++i)
values.push_back(hash_internal::Generator<T>()());
TypeParam m(values.begin(), values.end(), 123, hasher, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, InputIteratorBucketHashAlloc) {
InputIteratorBucketHashAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
TYPED_TEST_P(ConstructorTest, CopyConstructor) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
TypeParam m(123, hasher, equal, alloc);
for (size_t i = 0; i != 10; ++i) m.insert(hash_internal::Generator<T>()());
TypeParam n(m);
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_EQ(m.get_allocator(), n.get_allocator());
EXPECT_EQ(m, n);
EXPECT_NE(TypeParam(0, hasher, equal, alloc), n);
}
template <typename TypeParam>
void CopyConstructorAllocTest(std::false_type) {}
template <typename TypeParam>
void CopyConstructorAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
TypeParam m(123, hasher, equal, alloc);
for (size_t i = 0; i != 10; ++i) m.insert(hash_internal::Generator<T>()());
TypeParam n(m, A(11));
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_NE(m.get_allocator(), n.get_allocator());
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, CopyConstructorAlloc) {
CopyConstructorAllocTest<TypeParam>(expect_alloc_constructors<TypeParam>());
}
// TODO(alkis): Test non-propagating allocators on copy constructors.
TYPED_TEST_P(ConstructorTest, MoveConstructor) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
TypeParam m(123, hasher, equal, alloc);
for (size_t i = 0; i != 10; ++i) m.insert(hash_internal::Generator<T>()());
TypeParam t(m);
TypeParam n(std::move(t));
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_EQ(m.get_allocator(), n.get_allocator());
EXPECT_EQ(m, n);
}
template <typename TypeParam>
void MoveConstructorAllocTest(std::false_type) {}
template <typename TypeParam>
void MoveConstructorAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
TypeParam m(123, hasher, equal, alloc);
for (size_t i = 0; i != 10; ++i) m.insert(hash_internal::Generator<T>()());
TypeParam t(m);
TypeParam n(std::move(t), A(1));
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_NE(m.get_allocator(), n.get_allocator());
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, MoveConstructorAlloc) {
MoveConstructorAllocTest<TypeParam>(expect_alloc_constructors<TypeParam>());
}
// TODO(alkis): Test non-propagating allocators on move constructors.
TYPED_TEST_P(ConstructorTest, InitializerListBucketHashEqualAlloc) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::Generator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
TypeParam m(values, 123, hasher, equal, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.key_eq(), equal);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
template <typename TypeParam>
void InitializerListBucketAllocTest(std::false_type) {}
template <typename TypeParam>
void InitializerListBucketAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using A = typename TypeParam::allocator_type;
hash_internal::Generator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
A alloc(0);
TypeParam m(values, 123, alloc);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, InitializerListBucketAlloc) {
InitializerListBucketAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
template <typename TypeParam>
void InitializerListBucketHashAllocTest(std::false_type) {}
template <typename TypeParam>
void InitializerListBucketHashAllocTest(std::true_type) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using A = typename TypeParam::allocator_type;
H hasher;
A alloc(0);
hash_internal::Generator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
TypeParam m(values, 123, hasher, alloc);
EXPECT_EQ(m.hash_function(), hasher);
EXPECT_EQ(m.get_allocator(), alloc);
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_GE(m.bucket_count(), 123);
}
TYPED_TEST_P(ConstructorTest, InitializerListBucketHashAlloc) {
InitializerListBucketHashAllocTest<TypeParam>(expect_cxx14_apis<TypeParam>());
}
TYPED_TEST_P(ConstructorTest, CopyAssignment) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
hash_internal::Generator<T> gen;
TypeParam m({gen(), gen(), gen()}, 123, hasher, equal, alloc);
TypeParam n;
n = m;
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_EQ(m, n);
}
// TODO(alkis): Test [non-]propagating allocators on move/copy assignments
// (it depends on traits).
TYPED_TEST_P(ConstructorTest, MoveAssignment) {
using T = hash_internal::GeneratedType<TypeParam>;
using H = typename TypeParam::hasher;
using E = typename TypeParam::key_equal;
using A = typename TypeParam::allocator_type;
H hasher;
E equal;
A alloc(0);
hash_internal::Generator<T> gen;
TypeParam m({gen(), gen(), gen()}, 123, hasher, equal, alloc);
TypeParam t(m);
TypeParam n;
n = std::move(t);
EXPECT_EQ(m.hash_function(), n.hash_function());
EXPECT_EQ(m.key_eq(), n.key_eq());
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, AssignmentFromInitializerList) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::Generator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
TypeParam m;
m = values;
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
}
TYPED_TEST_P(ConstructorTest, AssignmentOverwritesExisting) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::Generator<T> gen;
TypeParam m({gen(), gen(), gen()});
TypeParam n({gen()});
n = m;
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, MoveAssignmentOverwritesExisting) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::Generator<T> gen;
TypeParam m({gen(), gen(), gen()});
TypeParam t(m);
TypeParam n({gen()});
n = std::move(t);
EXPECT_EQ(m, n);
}
TYPED_TEST_P(ConstructorTest, AssignmentFromInitializerListOverwritesExisting) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::Generator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
TypeParam m;
m = values;
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
}
TYPED_TEST_P(ConstructorTest, AssignmentOnSelf) {
using T = hash_internal::GeneratedType<TypeParam>;
hash_internal::Generator<T> gen;
std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()};
TypeParam m(values);
m = *&m; // Avoid -Wself-assign.
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
}
REGISTER_TYPED_TEST_SUITE_P(
ConstructorTest, NoArgs, BucketCount, BucketCountHash, BucketCountHashEqual,
BucketCountHashEqualAlloc, BucketCountAlloc, BucketCountHashAlloc, Alloc,
InputIteratorBucketHashEqualAlloc, InputIteratorBucketAlloc,
InputIteratorBucketHashAlloc, CopyConstructor, CopyConstructorAlloc,
MoveConstructor, MoveConstructorAlloc, InitializerListBucketHashEqualAlloc,
InitializerListBucketAlloc, InitializerListBucketHashAlloc, CopyAssignment,
MoveAssignment, AssignmentFromInitializerList, AssignmentOverwritesExisting,
MoveAssignmentOverwritesExisting,
AssignmentFromInitializerListOverwritesExisting, AssignmentOnSelf);
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_UNORDERED_SET_CONSTRUCTOR_TEST_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_UNORDERED_SET_LOOKUP_TEST_H_
#define ABSL_CONTAINER_INTERNAL_UNORDERED_SET_LOOKUP_TEST_H_
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/container/internal/hash_generator_testing.h"
#include "absl/container/internal/hash_policy_testing.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class UnordSet>
class LookupTest : public ::testing::Test {};
TYPED_TEST_SUITE_P(LookupTest);
TYPED_TEST_P(LookupTest, Count) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m;
for (const auto& v : values)
EXPECT_EQ(0, m.count(v)) << ::testing::PrintToString(v);
m.insert(values.begin(), values.end());
for (const auto& v : values)
EXPECT_EQ(1, m.count(v)) << ::testing::PrintToString(v);
}
TYPED_TEST_P(LookupTest, Find) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m;
for (const auto& v : values)
EXPECT_TRUE(m.end() == m.find(v)) << ::testing::PrintToString(v);
m.insert(values.begin(), values.end());
for (const auto& v : values) {
typename TypeParam::iterator it = m.find(v);
static_assert(std::is_same<const typename TypeParam::value_type&,
decltype(*it)>::value,
"");
static_assert(std::is_same<const typename TypeParam::value_type*,
decltype(it.operator->())>::value,
"");
EXPECT_TRUE(m.end() != it) << ::testing::PrintToString(v);
EXPECT_EQ(v, *it) << ::testing::PrintToString(v);
}
}
TYPED_TEST_P(LookupTest, EqualRange) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m;
for (const auto& v : values) {
auto r = m.equal_range(v);
ASSERT_EQ(0, std::distance(r.first, r.second));
}
m.insert(values.begin(), values.end());
for (const auto& v : values) {
auto r = m.equal_range(v);
ASSERT_EQ(1, std::distance(r.first, r.second));
EXPECT_EQ(v, *r.first);
}
}
REGISTER_TYPED_TEST_SUITE_P(LookupTest, Count, Find, EqualRange);
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_UNORDERED_SET_LOOKUP_TEST_H_

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// Copyright 2019 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_UNORDERED_SET_MEMBERS_TEST_H_
#define ABSL_CONTAINER_INTERNAL_UNORDERED_SET_MEMBERS_TEST_H_
#include <type_traits>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/meta/type_traits.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class UnordSet>
class MembersTest : public ::testing::Test {};
TYPED_TEST_SUITE_P(MembersTest);
template <typename T>
void UseType() {}
TYPED_TEST_P(MembersTest, Typedefs) {
EXPECT_TRUE((std::is_same<typename TypeParam::key_type,
typename TypeParam::value_type>()));
EXPECT_TRUE((absl::conjunction<
absl::negation<std::is_signed<typename TypeParam::size_type>>,
std::is_integral<typename TypeParam::size_type>>()));
EXPECT_TRUE((absl::conjunction<
std::is_signed<typename TypeParam::difference_type>,
std::is_integral<typename TypeParam::difference_type>>()));
EXPECT_TRUE((std::is_convertible<
decltype(std::declval<const typename TypeParam::hasher&>()(
std::declval<const typename TypeParam::key_type&>())),
size_t>()));
EXPECT_TRUE((std::is_convertible<
decltype(std::declval<const typename TypeParam::key_equal&>()(
std::declval<const typename TypeParam::key_type&>(),
std::declval<const typename TypeParam::key_type&>())),
bool>()));
EXPECT_TRUE((std::is_same<typename TypeParam::allocator_type::value_type,
typename TypeParam::value_type>()));
EXPECT_TRUE((std::is_same<typename TypeParam::value_type&,
typename TypeParam::reference>()));
EXPECT_TRUE((std::is_same<const typename TypeParam::value_type&,
typename TypeParam::const_reference>()));
EXPECT_TRUE((std::is_same<typename std::allocator_traits<
typename TypeParam::allocator_type>::pointer,
typename TypeParam::pointer>()));
EXPECT_TRUE(
(std::is_same<typename std::allocator_traits<
typename TypeParam::allocator_type>::const_pointer,
typename TypeParam::const_pointer>()));
}
TYPED_TEST_P(MembersTest, SimpleFunctions) {
EXPECT_GT(TypeParam().max_size(), 0);
}
TYPED_TEST_P(MembersTest, BeginEnd) {
TypeParam t = {typename TypeParam::value_type{}};
EXPECT_EQ(t.begin(), t.cbegin());
EXPECT_EQ(t.end(), t.cend());
EXPECT_NE(t.begin(), t.end());
EXPECT_NE(t.cbegin(), t.cend());
}
REGISTER_TYPED_TEST_SUITE_P(MembersTest, Typedefs, SimpleFunctions, BeginEnd);
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_UNORDERED_SET_MEMBERS_TEST_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_UNORDERED_SET_MODIFIERS_TEST_H_
#define ABSL_CONTAINER_INTERNAL_UNORDERED_SET_MODIFIERS_TEST_H_
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/container/internal/hash_generator_testing.h"
#include "absl/container/internal/hash_policy_testing.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class UnordSet>
class ModifiersTest : public ::testing::Test {};
TYPED_TEST_SUITE_P(ModifiersTest);
TYPED_TEST_P(ModifiersTest, Clear) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m(values.begin(), values.end());
ASSERT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
m.clear();
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
EXPECT_TRUE(m.empty());
}
TYPED_TEST_P(ModifiersTest, Insert) {
using T = hash_internal::GeneratedType<TypeParam>;
T val = hash_internal::Generator<T>()();
TypeParam m;
auto p = m.insert(val);
EXPECT_TRUE(p.second);
EXPECT_EQ(val, *p.first);
p = m.insert(val);
EXPECT_FALSE(p.second);
}
TYPED_TEST_P(ModifiersTest, InsertHint) {
using T = hash_internal::GeneratedType<TypeParam>;
T val = hash_internal::Generator<T>()();
TypeParam m;
auto it = m.insert(m.end(), val);
EXPECT_TRUE(it != m.end());
EXPECT_EQ(val, *it);
it = m.insert(it, val);
EXPECT_TRUE(it != m.end());
EXPECT_EQ(val, *it);
}
TYPED_TEST_P(ModifiersTest, InsertRange) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m;
m.insert(values.begin(), values.end());
ASSERT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
}
TYPED_TEST_P(ModifiersTest, InsertWithinCapacity) {
using T = hash_internal::GeneratedType<TypeParam>;
T val = hash_internal::Generator<T>()();
TypeParam m;
m.reserve(10);
const size_t original_capacity = m.bucket_count();
m.insert(val);
EXPECT_EQ(m.bucket_count(), original_capacity);
m.insert(val);
EXPECT_EQ(m.bucket_count(), original_capacity);
}
TYPED_TEST_P(ModifiersTest, InsertRangeWithinCapacity) {
#if !defined(__GLIBCXX__)
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> base_values;
std::generate_n(std::back_inserter(base_values), 10,
hash_internal::Generator<T>());
std::vector<T> values;
while (values.size() != 100) {
values.insert(values.end(), base_values.begin(), base_values.end());
}
TypeParam m;
m.reserve(10);
const size_t original_capacity = m.bucket_count();
m.insert(values.begin(), values.end());
EXPECT_EQ(m.bucket_count(), original_capacity);
#endif
}
TYPED_TEST_P(ModifiersTest, Emplace) {
using T = hash_internal::GeneratedType<TypeParam>;
T val = hash_internal::Generator<T>()();
TypeParam m;
// TODO(alkis): We need a way to run emplace in a more meaningful way. Perhaps
// with test traits/policy.
auto p = m.emplace(val);
EXPECT_TRUE(p.second);
EXPECT_EQ(val, *p.first);
p = m.emplace(val);
EXPECT_FALSE(p.second);
EXPECT_EQ(val, *p.first);
}
TYPED_TEST_P(ModifiersTest, EmplaceHint) {
using T = hash_internal::GeneratedType<TypeParam>;
T val = hash_internal::Generator<T>()();
TypeParam m;
// TODO(alkis): We need a way to run emplace in a more meaningful way. Perhaps
// with test traits/policy.
auto it = m.emplace_hint(m.end(), val);
EXPECT_EQ(val, *it);
it = m.emplace_hint(it, val);
EXPECT_EQ(val, *it);
}
template <class V>
using IfNotVoid = typename std::enable_if<!std::is_void<V>::value, V>::type;
// In openmap we chose not to return the iterator from erase because that's
// more expensive. As such we adapt erase to return an iterator here.
struct EraseFirst {
template <class Map>
auto operator()(Map* m, int) const
-> IfNotVoid<decltype(m->erase(m->begin()))> {
return m->erase(m->begin());
}
template <class Map>
typename Map::iterator operator()(Map* m, ...) const {
auto it = m->begin();
m->erase(it++);
return it;
}
};
TYPED_TEST_P(ModifiersTest, Erase) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m(values.begin(), values.end());
ASSERT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
std::vector<T> values2;
for (const auto& val : values)
if (val != *m.begin()) values2.push_back(val);
auto it = EraseFirst()(&m, 0);
ASSERT_TRUE(it != m.end());
EXPECT_EQ(1, std::count(values2.begin(), values2.end(), *it));
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values2.begin(),
values2.end()));
}
TYPED_TEST_P(ModifiersTest, EraseRange) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m(values.begin(), values.end());
ASSERT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
auto it = m.erase(m.begin(), m.end());
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAre());
EXPECT_TRUE(it == m.end());
}
TYPED_TEST_P(ModifiersTest, EraseKey) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> values;
std::generate_n(std::back_inserter(values), 10,
hash_internal::Generator<T>());
TypeParam m(values.begin(), values.end());
ASSERT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values));
EXPECT_EQ(1, m.erase(values[0]));
EXPECT_EQ(0, std::count(m.begin(), m.end(), values[0]));
EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values.begin() + 1,
values.end()));
}
TYPED_TEST_P(ModifiersTest, Swap) {
using T = hash_internal::GeneratedType<TypeParam>;
std::vector<T> v1;
std::vector<T> v2;
std::generate_n(std::back_inserter(v1), 5, hash_internal::Generator<T>());
std::generate_n(std::back_inserter(v2), 5, hash_internal::Generator<T>());
TypeParam m1(v1.begin(), v1.end());
TypeParam m2(v2.begin(), v2.end());
EXPECT_THAT(keys(m1), ::testing::UnorderedElementsAreArray(v1));
EXPECT_THAT(keys(m2), ::testing::UnorderedElementsAreArray(v2));
m1.swap(m2);
EXPECT_THAT(keys(m1), ::testing::UnorderedElementsAreArray(v2));
EXPECT_THAT(keys(m2), ::testing::UnorderedElementsAreArray(v1));
}
// TODO(alkis): Write tests for extract.
// TODO(alkis): Write tests for merge.
REGISTER_TYPED_TEST_SUITE_P(ModifiersTest, Clear, Insert, InsertHint,
InsertRange, InsertWithinCapacity,
InsertRangeWithinCapacity, Emplace, EmplaceHint,
Erase, EraseRange, EraseKey, Swap);
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_UNORDERED_SET_MODIFIERS_TEST_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: node_hash_map.h
// -----------------------------------------------------------------------------
//
// An `absl::node_hash_map<K, V>` is an unordered associative container of
// unique keys and associated values designed to be a more efficient replacement
// for `std::unordered_map`. Like `unordered_map`, search, insertion, and
// deletion of map elements can be done as an `O(1)` operation. However,
// `node_hash_map` (and other unordered associative containers known as the
// collection of Abseil "Swiss tables") contain other optimizations that result
// in both memory and computation advantages.
//
// In most cases, your default choice for a hash map should be a map of type
// `flat_hash_map`. However, if you need pointer stability and cannot store
// a `flat_hash_map` with `unique_ptr` elements, a `node_hash_map` may be a
// valid alternative. As well, if you are migrating your code from using
// `std::unordered_map`, a `node_hash_map` provides a more straightforward
// migration, because it guarantees pointer stability. Consider migrating to
// `node_hash_map` and perhaps converting to a more efficient `flat_hash_map`
// upon further review.
#ifndef ABSL_CONTAINER_NODE_HASH_MAP_H_
#define ABSL_CONTAINER_NODE_HASH_MAP_H_
#include <tuple>
#include <type_traits>
#include <utility>
#include "absl/algorithm/container.h"
#include "absl/base/macros.h"
#include "absl/container/internal/container_memory.h"
#include "absl/container/internal/hash_function_defaults.h" // IWYU pragma: export
#include "absl/container/internal/node_slot_policy.h"
#include "absl/container/internal/raw_hash_map.h" // IWYU pragma: export
#include "absl/memory/memory.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <class Key, class Value>
class NodeHashMapPolicy;
} // namespace container_internal
// -----------------------------------------------------------------------------
// absl::node_hash_map
// -----------------------------------------------------------------------------
//
// An `absl::node_hash_map<K, V>` is an unordered associative container which
// has been optimized for both speed and memory footprint in most common use
// cases. Its interface is similar to that of `std::unordered_map<K, V>` with
// the following notable differences:
//
// * Supports heterogeneous lookup, through `find()`, `operator[]()` and
// `insert()`, provided that the map is provided a compatible heterogeneous
// hashing function and equality operator.
// * Contains a `capacity()` member function indicating the number of element
// slots (open, deleted, and empty) within the hash map.
// * Returns `void` from the `erase(iterator)` overload.
//
// By default, `node_hash_map` uses the `absl::Hash` hashing framework.
// All fundamental and Abseil types that support the `absl::Hash` framework have
// a compatible equality operator for comparing insertions into `node_hash_map`.
// If your type is not yet supported by the `absl::Hash` framework, see
// absl/hash/hash.h for information on extending Abseil hashing to user-defined
// types.
//
// Using `absl::node_hash_map` at interface boundaries in dynamically loaded
// libraries (e.g. .dll, .so) is unsupported due to way `absl::Hash` values may
// be randomized across dynamically loaded libraries.
//
// Example:
//
// // Create a node hash map of three strings (that map to strings)
// absl::node_hash_map<std::string, std::string> ducks =
// {{"a", "huey"}, {"b", "dewey"}, {"c", "louie"}};
//
// // Insert a new element into the node hash map
// ducks.insert({"d", "donald"}};
//
// // Force a rehash of the node hash map
// ducks.rehash(0);
//
// // Find the element with the key "b"
// std::string search_key = "b";
// auto result = ducks.find(search_key);
// if (result != ducks.end()) {
// std::cout << "Result: " << result->second << std::endl;
// }
template <class Key, class Value,
class Hash = absl::container_internal::hash_default_hash<Key>,
class Eq = absl::container_internal::hash_default_eq<Key>,
class Alloc = std::allocator<std::pair<const Key, Value>>>
class node_hash_map
: public absl::container_internal::raw_hash_map<
absl::container_internal::NodeHashMapPolicy<Key, Value>, Hash, Eq,
Alloc> {
using Base = typename node_hash_map::raw_hash_map;
public:
// Constructors and Assignment Operators
//
// A node_hash_map supports the same overload set as `std::unordered_map`
// for construction and assignment:
//
// * Default constructor
//
// // No allocation for the table's elements is made.
// absl::node_hash_map<int, std::string> map1;
//
// * Initializer List constructor
//
// absl::node_hash_map<int, std::string> map2 =
// {{1, "huey"}, {2, "dewey"}, {3, "louie"},};
//
// * Copy constructor
//
// absl::node_hash_map<int, std::string> map3(map2);
//
// * Copy assignment operator
//
// // Hash functor and Comparator are copied as well
// absl::node_hash_map<int, std::string> map4;
// map4 = map3;
//
// * Move constructor
//
// // Move is guaranteed efficient
// absl::node_hash_map<int, std::string> map5(std::move(map4));
//
// * Move assignment operator
//
// // May be efficient if allocators are compatible
// absl::node_hash_map<int, std::string> map6;
// map6 = std::move(map5);
//
// * Range constructor
//
// std::vector<std::pair<int, std::string>> v = {{1, "a"}, {2, "b"}};
// absl::node_hash_map<int, std::string> map7(v.begin(), v.end());
node_hash_map() {}
using Base::Base;
// node_hash_map::begin()
//
// Returns an iterator to the beginning of the `node_hash_map`.
using Base::begin;
// node_hash_map::cbegin()
//
// Returns a const iterator to the beginning of the `node_hash_map`.
using Base::cbegin;
// node_hash_map::cend()
//
// Returns a const iterator to the end of the `node_hash_map`.
using Base::cend;
// node_hash_map::end()
//
// Returns an iterator to the end of the `node_hash_map`.
using Base::end;
// node_hash_map::capacity()
//
// Returns the number of element slots (assigned, deleted, and empty)
// available within the `node_hash_map`.
//
// NOTE: this member function is particular to `absl::node_hash_map` and is
// not provided in the `std::unordered_map` API.
using Base::capacity;
// node_hash_map::empty()
//
// Returns whether or not the `node_hash_map` is empty.
using Base::empty;
// node_hash_map::max_size()
//
// Returns the largest theoretical possible number of elements within a
// `node_hash_map` under current memory constraints. This value can be thought
// of as the largest value of `std::distance(begin(), end())` for a
// `node_hash_map<K, V>`.
using Base::max_size;
// node_hash_map::size()
//
// Returns the number of elements currently within the `node_hash_map`.
using Base::size;
// node_hash_map::clear()
//
// Removes all elements from the `node_hash_map`. Invalidates any references,
// pointers, or iterators referring to contained elements.
//
// NOTE: this operation may shrink the underlying buffer. To avoid shrinking
// the underlying buffer call `erase(begin(), end())`.
using Base::clear;
// node_hash_map::erase()
//
// Erases elements within the `node_hash_map`. Erasing does not trigger a
// rehash. Overloads are listed below.
//
// void erase(const_iterator pos):
//
// Erases the element at `position` of the `node_hash_map`, returning
// `void`.
//
// NOTE: this return behavior is different than that of STL containers in
// general and `std::unordered_map` in particular.
//
// iterator erase(const_iterator first, const_iterator last):
//
// Erases the elements in the open interval [`first`, `last`), returning an
// iterator pointing to `last`. The special case of calling
// `erase(begin(), end())` resets the reserved growth such that if
// `reserve(N)` has previously been called and there has been no intervening
// call to `clear()`, then after calling `erase(begin(), end())`, it is safe
// to assume that inserting N elements will not cause a rehash.
//
// size_type erase(const key_type& key):
//
// Erases the element with the matching key, if it exists, returning the
// number of elements erased (0 or 1).
using Base::erase;
// node_hash_map::insert()
//
// Inserts an element of the specified value into the `node_hash_map`,
// returning an iterator pointing to the newly inserted element, provided that
// an element with the given key does not already exist. If rehashing occurs
// due to the insertion, all iterators are invalidated. Overloads are listed
// below.
//
// std::pair<iterator,bool> insert(const init_type& value):
//
// Inserts a value into the `node_hash_map`. Returns a pair consisting of an
// iterator to the inserted element (or to the element that prevented the
// insertion) and a `bool` denoting whether the insertion took place.
//
// std::pair<iterator,bool> insert(T&& value):
// std::pair<iterator,bool> insert(init_type&& value):
//
// Inserts a moveable value into the `node_hash_map`. Returns a `std::pair`
// consisting of an iterator to the inserted element (or to the element that
// prevented the insertion) and a `bool` denoting whether the insertion took
// place.
//
// iterator insert(const_iterator hint, const init_type& value):
// iterator insert(const_iterator hint, T&& value):
// iterator insert(const_iterator hint, init_type&& value);
//
// Inserts a value, using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search. Returns an iterator to the
// inserted element, or to the existing element that prevented the
// insertion.
//
// void insert(InputIterator first, InputIterator last):
//
// Inserts a range of values [`first`, `last`).
//
// NOTE: Although the STL does not specify which element may be inserted if
// multiple keys compare equivalently, for `node_hash_map` we guarantee the
// first match is inserted.
//
// void insert(std::initializer_list<init_type> ilist):
//
// Inserts the elements within the initializer list `ilist`.
//
// NOTE: Although the STL does not specify which element may be inserted if
// multiple keys compare equivalently within the initializer list, for
// `node_hash_map` we guarantee the first match is inserted.
using Base::insert;
// node_hash_map::insert_or_assign()
//
// Inserts an element of the specified value into the `node_hash_map` provided
// that a value with the given key does not already exist, or replaces it with
// the element value if a key for that value already exists, returning an
// iterator pointing to the newly inserted element. If rehashing occurs due to
// the insertion, all iterators are invalidated. Overloads are listed
// below.
//
// std::pair<iterator, bool> insert_or_assign(const init_type& k, T&& obj):
// std::pair<iterator, bool> insert_or_assign(init_type&& k, T&& obj):
//
// Inserts/Assigns (or moves) the element of the specified key into the
// `node_hash_map`.
//
// iterator insert_or_assign(const_iterator hint,
// const init_type& k, T&& obj):
// iterator insert_or_assign(const_iterator hint, init_type&& k, T&& obj):
//
// Inserts/Assigns (or moves) the element of the specified key into the
// `node_hash_map` using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search.
using Base::insert_or_assign;
// node_hash_map::emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `node_hash_map`, provided that no element with the given key
// already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately. Prefer `try_emplace()` unless your key is not
// copyable or moveable.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
using Base::emplace;
// node_hash_map::emplace_hint()
//
// Inserts an element of the specified value by constructing it in-place
// within the `node_hash_map`, using the position of `hint` as a non-binding
// suggestion for where to begin the insertion search, and only inserts
// provided that no element with the given key already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately. Prefer `try_emplace()` unless your key is not
// copyable or moveable.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
using Base::emplace_hint;
// node_hash_map::try_emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `node_hash_map`, provided that no element with the given key
// already exists. Unlike `emplace()`, if an element with the given key
// already exists, we guarantee that no element is constructed.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
// Overloads are listed below.
//
// std::pair<iterator, bool> try_emplace(const key_type& k, Args&&... args):
// std::pair<iterator, bool> try_emplace(key_type&& k, Args&&... args):
//
// Inserts (via copy or move) the element of the specified key into the
// `node_hash_map`.
//
// iterator try_emplace(const_iterator hint,
// const key_type& k, Args&&... args):
// iterator try_emplace(const_iterator hint, key_type&& k, Args&&... args):
//
// Inserts (via copy or move) the element of the specified key into the
// `node_hash_map` using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search.
//
// All `try_emplace()` overloads make the same guarantees regarding rvalue
// arguments as `std::unordered_map::try_emplace()`, namely that these
// functions will not move from rvalue arguments if insertions do not happen.
using Base::try_emplace;
// node_hash_map::extract()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle. Overloads are listed below.
//
// node_type extract(const_iterator position):
//
// Extracts the key,value pair of the element at the indicated position and
// returns a node handle owning that extracted data.
//
// node_type extract(const key_type& x):
//
// Extracts the key,value pair of the element with a key matching the passed
// key value and returns a node handle owning that extracted data. If the
// `node_hash_map` does not contain an element with a matching key, this
// function returns an empty node handle.
//
// NOTE: when compiled in an earlier version of C++ than C++17,
// `node_type::key()` returns a const reference to the key instead of a
// mutable reference. We cannot safely return a mutable reference without
// std::launder (which is not available before C++17).
using Base::extract;
// node_hash_map::merge()
//
// Extracts elements from a given `source` node hash map into this
// `node_hash_map`. If the destination `node_hash_map` already contains an
// element with an equivalent key, that element is not extracted.
using Base::merge;
// node_hash_map::swap(node_hash_map& other)
//
// Exchanges the contents of this `node_hash_map` with those of the `other`
// node hash map, avoiding invocation of any move, copy, or swap operations on
// individual elements.
//
// All iterators and references on the `node_hash_map` remain valid, excepting
// for the past-the-end iterator, which is invalidated.
//
// `swap()` requires that the node hash map's hashing and key equivalence
// functions be Swappable, and are exchanged using unqualified calls to
// non-member `swap()`. If the map's allocator has
// `std::allocator_traits<allocator_type>::propagate_on_container_swap::value`
// set to `true`, the allocators are also exchanged using an unqualified call
// to non-member `swap()`; otherwise, the allocators are not swapped.
using Base::swap;
// node_hash_map::rehash(count)
//
// Rehashes the `node_hash_map`, setting the number of slots to be at least
// the passed value. If the new number of slots increases the load factor more
// than the current maximum load factor
// (`count` < `size()` / `max_load_factor()`), then the new number of slots
// will be at least `size()` / `max_load_factor()`.
//
// To force a rehash, pass rehash(0).
using Base::rehash;
// node_hash_map::reserve(count)
//
// Sets the number of slots in the `node_hash_map` to the number needed to
// accommodate at least `count` total elements without exceeding the current
// maximum load factor, and may rehash the container if needed.
using Base::reserve;
// node_hash_map::at()
//
// Returns a reference to the mapped value of the element with key equivalent
// to the passed key.
using Base::at;
// node_hash_map::contains()
//
// Determines whether an element with a key comparing equal to the given `key`
// exists within the `node_hash_map`, returning `true` if so or `false`
// otherwise.
using Base::contains;
// node_hash_map::count(const Key& key) const
//
// Returns the number of elements with a key comparing equal to the given
// `key` within the `node_hash_map`. note that this function will return
// either `1` or `0` since duplicate keys are not allowed within a
// `node_hash_map`.
using Base::count;
// node_hash_map::equal_range()
//
// Returns a closed range [first, last], defined by a `std::pair` of two
// iterators, containing all elements with the passed key in the
// `node_hash_map`.
using Base::equal_range;
// node_hash_map::find()
//
// Finds an element with the passed `key` within the `node_hash_map`.
using Base::find;
// node_hash_map::operator[]()
//
// Returns a reference to the value mapped to the passed key within the
// `node_hash_map`, performing an `insert()` if the key does not already
// exist. If an insertion occurs and results in a rehashing of the container,
// all iterators are invalidated. Otherwise iterators are not affected and
// references are not invalidated. Overloads are listed below.
//
// T& operator[](const Key& key):
//
// Inserts an init_type object constructed in-place if the element with the
// given key does not exist.
//
// T& operator[](Key&& key):
//
// Inserts an init_type object constructed in-place provided that an element
// with the given key does not exist.
using Base::operator[];
// node_hash_map::bucket_count()
//
// Returns the number of "buckets" within the `node_hash_map`.
using Base::bucket_count;
// node_hash_map::load_factor()
//
// Returns the current load factor of the `node_hash_map` (the average number
// of slots occupied with a value within the hash map).
using Base::load_factor;
// node_hash_map::max_load_factor()
//
// Manages the maximum load factor of the `node_hash_map`. Overloads are
// listed below.
//
// float node_hash_map::max_load_factor()
//
// Returns the current maximum load factor of the `node_hash_map`.
//
// void node_hash_map::max_load_factor(float ml)
//
// Sets the maximum load factor of the `node_hash_map` to the passed value.
//
// NOTE: This overload is provided only for API compatibility with the STL;
// `node_hash_map` will ignore any set load factor and manage its rehashing
// internally as an implementation detail.
using Base::max_load_factor;
// node_hash_map::get_allocator()
//
// Returns the allocator function associated with this `node_hash_map`.
using Base::get_allocator;
// node_hash_map::hash_function()
//
// Returns the hashing function used to hash the keys within this
// `node_hash_map`.
using Base::hash_function;
// node_hash_map::key_eq()
//
// Returns the function used for comparing keys equality.
using Base::key_eq;
};
// erase_if(node_hash_map<>, Pred)
//
// Erases all elements that satisfy the predicate `pred` from the container `c`.
// Returns the number of erased elements.
template <typename K, typename V, typename H, typename E, typename A,
typename Predicate>
typename node_hash_map<K, V, H, E, A>::size_type erase_if(
node_hash_map<K, V, H, E, A>& c, Predicate pred) {
return container_internal::EraseIf(pred, &c);
}
namespace container_internal {
template <class Key, class Value>
class NodeHashMapPolicy
: public absl::container_internal::node_slot_policy<
std::pair<const Key, Value>&, NodeHashMapPolicy<Key, Value>> {
using value_type = std::pair<const Key, Value>;
public:
using key_type = Key;
using mapped_type = Value;
using init_type = std::pair</*non const*/ key_type, mapped_type>;
template <class Allocator, class... Args>
static value_type* new_element(Allocator* alloc, Args&&... args) {
using PairAlloc = typename absl::allocator_traits<
Allocator>::template rebind_alloc<value_type>;
PairAlloc pair_alloc(*alloc);
value_type* res =
absl::allocator_traits<PairAlloc>::allocate(pair_alloc, 1);
absl::allocator_traits<PairAlloc>::construct(pair_alloc, res,
std::forward<Args>(args)...);
return res;
}
template <class Allocator>
static void delete_element(Allocator* alloc, value_type* pair) {
using PairAlloc = typename absl::allocator_traits<
Allocator>::template rebind_alloc<value_type>;
PairAlloc pair_alloc(*alloc);
absl::allocator_traits<PairAlloc>::destroy(pair_alloc, pair);
absl::allocator_traits<PairAlloc>::deallocate(pair_alloc, pair, 1);
}
template <class F, class... Args>
static decltype(absl::container_internal::DecomposePair(
std::declval<F>(), std::declval<Args>()...))
apply(F&& f, Args&&... args) {
return absl::container_internal::DecomposePair(std::forward<F>(f),
std::forward<Args>(args)...);
}
static size_t element_space_used(const value_type*) {
return sizeof(value_type);
}
static Value& value(value_type* elem) { return elem->second; }
static const Value& value(const value_type* elem) { return elem->second; }
};
} // namespace container_internal
namespace container_algorithm_internal {
// Specialization of trait in absl/algorithm/container.h
template <class Key, class T, class Hash, class KeyEqual, class Allocator>
struct IsUnorderedContainer<
absl::node_hash_map<Key, T, Hash, KeyEqual, Allocator>> : std::true_type {};
} // namespace container_algorithm_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_NODE_HASH_MAP_H_

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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: node_hash_set.h
// -----------------------------------------------------------------------------
//
// An `absl::node_hash_set<T>` is an unordered associative container designed to
// be a more efficient replacement for `std::unordered_set`. Like
// `unordered_set`, search, insertion, and deletion of set elements can be done
// as an `O(1)` operation. However, `node_hash_set` (and other unordered
// associative containers known as the collection of Abseil "Swiss tables")
// contain other optimizations that result in both memory and computation
// advantages.
//
// In most cases, your default choice for a hash table should be a map of type
// `flat_hash_map` or a set of type `flat_hash_set`. However, if you need
// pointer stability, a `node_hash_set` should be your preferred choice. As
// well, if you are migrating your code from using `std::unordered_set`, a
// `node_hash_set` should be an easy migration. Consider migrating to
// `node_hash_set` and perhaps converting to a more efficient `flat_hash_set`
// upon further review.
#ifndef ABSL_CONTAINER_NODE_HASH_SET_H_
#define ABSL_CONTAINER_NODE_HASH_SET_H_
#include <type_traits>
#include "absl/algorithm/container.h"
#include "absl/base/macros.h"
#include "absl/container/internal/hash_function_defaults.h" // IWYU pragma: export
#include "absl/container/internal/node_slot_policy.h"
#include "absl/container/internal/raw_hash_set.h" // IWYU pragma: export
#include "absl/memory/memory.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
template <typename T>
struct NodeHashSetPolicy;
} // namespace container_internal
// -----------------------------------------------------------------------------
// absl::node_hash_set
// -----------------------------------------------------------------------------
//
// An `absl::node_hash_set<T>` is an unordered associative container which
// has been optimized for both speed and memory footprint in most common use
// cases. Its interface is similar to that of `std::unordered_set<T>` with the
// following notable differences:
//
// * Supports heterogeneous lookup, through `find()`, `operator[]()` and
// `insert()`, provided that the set is provided a compatible heterogeneous
// hashing function and equality operator.
// * Contains a `capacity()` member function indicating the number of element
// slots (open, deleted, and empty) within the hash set.
// * Returns `void` from the `erase(iterator)` overload.
//
// By default, `node_hash_set` uses the `absl::Hash` hashing framework.
// All fundamental and Abseil types that support the `absl::Hash` framework have
// a compatible equality operator for comparing insertions into `node_hash_set`.
// If your type is not yet supported by the `absl::Hash` framework, see
// absl/hash/hash.h for information on extending Abseil hashing to user-defined
// types.
//
// Using `absl::node_hash_set` at interface boundaries in dynamically loaded
// libraries (e.g. .dll, .so) is unsupported due to way `absl::Hash` values may
// be randomized across dynamically loaded libraries.
//
// Example:
//
// // Create a node hash set of three strings
// absl::node_hash_set<std::string> ducks =
// {"huey", "dewey", "louie"};
//
// // Insert a new element into the node hash set
// ducks.insert("donald");
//
// // Force a rehash of the node hash set
// ducks.rehash(0);
//
// // See if "dewey" is present
// if (ducks.contains("dewey")) {
// std::cout << "We found dewey!" << std::endl;
// }
template <class T, class Hash = absl::container_internal::hash_default_hash<T>,
class Eq = absl::container_internal::hash_default_eq<T>,
class Alloc = std::allocator<T>>
class node_hash_set
: public absl::container_internal::raw_hash_set<
absl::container_internal::NodeHashSetPolicy<T>, Hash, Eq, Alloc> {
using Base = typename node_hash_set::raw_hash_set;
public:
// Constructors and Assignment Operators
//
// A node_hash_set supports the same overload set as `std::unordered_set`
// for construction and assignment:
//
// * Default constructor
//
// // No allocation for the table's elements is made.
// absl::node_hash_set<std::string> set1;
//
// * Initializer List constructor
//
// absl::node_hash_set<std::string> set2 =
// {{"huey"}, {"dewey"}, {"louie"}};
//
// * Copy constructor
//
// absl::node_hash_set<std::string> set3(set2);
//
// * Copy assignment operator
//
// // Hash functor and Comparator are copied as well
// absl::node_hash_set<std::string> set4;
// set4 = set3;
//
// * Move constructor
//
// // Move is guaranteed efficient
// absl::node_hash_set<std::string> set5(std::move(set4));
//
// * Move assignment operator
//
// // May be efficient if allocators are compatible
// absl::node_hash_set<std::string> set6;
// set6 = std::move(set5);
//
// * Range constructor
//
// std::vector<std::string> v = {"a", "b"};
// absl::node_hash_set<std::string> set7(v.begin(), v.end());
node_hash_set() {}
using Base::Base;
// node_hash_set::begin()
//
// Returns an iterator to the beginning of the `node_hash_set`.
using Base::begin;
// node_hash_set::cbegin()
//
// Returns a const iterator to the beginning of the `node_hash_set`.
using Base::cbegin;
// node_hash_set::cend()
//
// Returns a const iterator to the end of the `node_hash_set`.
using Base::cend;
// node_hash_set::end()
//
// Returns an iterator to the end of the `node_hash_set`.
using Base::end;
// node_hash_set::capacity()
//
// Returns the number of element slots (assigned, deleted, and empty)
// available within the `node_hash_set`.
//
// NOTE: this member function is particular to `absl::node_hash_set` and is
// not provided in the `std::unordered_set` API.
using Base::capacity;
// node_hash_set::empty()
//
// Returns whether or not the `node_hash_set` is empty.
using Base::empty;
// node_hash_set::max_size()
//
// Returns the largest theoretical possible number of elements within a
// `node_hash_set` under current memory constraints. This value can be thought
// of the largest value of `std::distance(begin(), end())` for a
// `node_hash_set<T>`.
using Base::max_size;
// node_hash_set::size()
//
// Returns the number of elements currently within the `node_hash_set`.
using Base::size;
// node_hash_set::clear()
//
// Removes all elements from the `node_hash_set`. Invalidates any references,
// pointers, or iterators referring to contained elements.
//
// NOTE: this operation may shrink the underlying buffer. To avoid shrinking
// the underlying buffer call `erase(begin(), end())`.
using Base::clear;
// node_hash_set::erase()
//
// Erases elements within the `node_hash_set`. Erasing does not trigger a
// rehash. Overloads are listed below.
//
// void erase(const_iterator pos):
//
// Erases the element at `position` of the `node_hash_set`, returning
// `void`.
//
// NOTE: this return behavior is different than that of STL containers in
// general and `std::unordered_set` in particular.
//
// iterator erase(const_iterator first, const_iterator last):
//
// Erases the elements in the open interval [`first`, `last`), returning an
// iterator pointing to `last`. The special case of calling
// `erase(begin(), end())` resets the reserved growth such that if
// `reserve(N)` has previously been called and there has been no intervening
// call to `clear()`, then after calling `erase(begin(), end())`, it is safe
// to assume that inserting N elements will not cause a rehash.
//
// size_type erase(const key_type& key):
//
// Erases the element with the matching key, if it exists, returning the
// number of elements erased (0 or 1).
using Base::erase;
// node_hash_set::insert()
//
// Inserts an element of the specified value into the `node_hash_set`,
// returning an iterator pointing to the newly inserted element, provided that
// an element with the given key does not already exist. If rehashing occurs
// due to the insertion, all iterators are invalidated. Overloads are listed
// below.
//
// std::pair<iterator,bool> insert(const T& value):
//
// Inserts a value into the `node_hash_set`. Returns a pair consisting of an
// iterator to the inserted element (or to the element that prevented the
// insertion) and a bool denoting whether the insertion took place.
//
// std::pair<iterator,bool> insert(T&& value):
//
// Inserts a moveable value into the `node_hash_set`. Returns a pair
// consisting of an iterator to the inserted element (or to the element that
// prevented the insertion) and a bool denoting whether the insertion took
// place.
//
// iterator insert(const_iterator hint, const T& value):
// iterator insert(const_iterator hint, T&& value):
//
// Inserts a value, using the position of `hint` as a non-binding suggestion
// for where to begin the insertion search. Returns an iterator to the
// inserted element, or to the existing element that prevented the
// insertion.
//
// void insert(InputIterator first, InputIterator last):
//
// Inserts a range of values [`first`, `last`).
//
// NOTE: Although the STL does not specify which element may be inserted if
// multiple keys compare equivalently, for `node_hash_set` we guarantee the
// first match is inserted.
//
// void insert(std::initializer_list<T> ilist):
//
// Inserts the elements within the initializer list `ilist`.
//
// NOTE: Although the STL does not specify which element may be inserted if
// multiple keys compare equivalently within the initializer list, for
// `node_hash_set` we guarantee the first match is inserted.
using Base::insert;
// node_hash_set::emplace()
//
// Inserts an element of the specified value by constructing it in-place
// within the `node_hash_set`, provided that no element with the given key
// already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
using Base::emplace;
// node_hash_set::emplace_hint()
//
// Inserts an element of the specified value by constructing it in-place
// within the `node_hash_set`, using the position of `hint` as a non-binding
// suggestion for where to begin the insertion search, and only inserts
// provided that no element with the given key already exists.
//
// The element may be constructed even if there already is an element with the
// key in the container, in which case the newly constructed element will be
// destroyed immediately.
//
// If rehashing occurs due to the insertion, all iterators are invalidated.
using Base::emplace_hint;
// node_hash_set::extract()
//
// Extracts the indicated element, erasing it in the process, and returns it
// as a C++17-compatible node handle. Overloads are listed below.
//
// node_type extract(const_iterator position):
//
// Extracts the element at the indicated position and returns a node handle
// owning that extracted data.
//
// node_type extract(const key_type& x):
//
// Extracts the element with the key matching the passed key value and
// returns a node handle owning that extracted data. If the `node_hash_set`
// does not contain an element with a matching key, this function returns an
// empty node handle.
using Base::extract;
// node_hash_set::merge()
//
// Extracts elements from a given `source` node hash set into this
// `node_hash_set`. If the destination `node_hash_set` already contains an
// element with an equivalent key, that element is not extracted.
using Base::merge;
// node_hash_set::swap(node_hash_set& other)
//
// Exchanges the contents of this `node_hash_set` with those of the `other`
// node hash set, avoiding invocation of any move, copy, or swap operations on
// individual elements.
//
// All iterators and references on the `node_hash_set` remain valid, excepting
// for the past-the-end iterator, which is invalidated.
//
// `swap()` requires that the node hash set's hashing and key equivalence
// functions be Swappable, and are exchanged using unqualified calls to
// non-member `swap()`. If the set's allocator has
// `std::allocator_traits<allocator_type>::propagate_on_container_swap::value`
// set to `true`, the allocators are also exchanged using an unqualified call
// to non-member `swap()`; otherwise, the allocators are not swapped.
using Base::swap;
// node_hash_set::rehash(count)
//
// Rehashes the `node_hash_set`, setting the number of slots to be at least
// the passed value. If the new number of slots increases the load factor more
// than the current maximum load factor
// (`count` < `size()` / `max_load_factor()`), then the new number of slots
// will be at least `size()` / `max_load_factor()`.
//
// To force a rehash, pass rehash(0).
//
// NOTE: unlike behavior in `std::unordered_set`, references are also
// invalidated upon a `rehash()`.
using Base::rehash;
// node_hash_set::reserve(count)
//
// Sets the number of slots in the `node_hash_set` to the number needed to
// accommodate at least `count` total elements without exceeding the current
// maximum load factor, and may rehash the container if needed.
using Base::reserve;
// node_hash_set::contains()
//
// Determines whether an element comparing equal to the given `key` exists
// within the `node_hash_set`, returning `true` if so or `false` otherwise.
using Base::contains;
// node_hash_set::count(const Key& key) const
//
// Returns the number of elements comparing equal to the given `key` within
// the `node_hash_set`. note that this function will return either `1` or `0`
// since duplicate elements are not allowed within a `node_hash_set`.
using Base::count;
// node_hash_set::equal_range()
//
// Returns a closed range [first, last], defined by a `std::pair` of two
// iterators, containing all elements with the passed key in the
// `node_hash_set`.
using Base::equal_range;
// node_hash_set::find()
//
// Finds an element with the passed `key` within the `node_hash_set`.
using Base::find;
// node_hash_set::bucket_count()
//
// Returns the number of "buckets" within the `node_hash_set`. Note that
// because a node hash set contains all elements within its internal storage,
// this value simply equals the current capacity of the `node_hash_set`.
using Base::bucket_count;
// node_hash_set::load_factor()
//
// Returns the current load factor of the `node_hash_set` (the average number
// of slots occupied with a value within the hash set).
using Base::load_factor;
// node_hash_set::max_load_factor()
//
// Manages the maximum load factor of the `node_hash_set`. Overloads are
// listed below.
//
// float node_hash_set::max_load_factor()
//
// Returns the current maximum load factor of the `node_hash_set`.
//
// void node_hash_set::max_load_factor(float ml)
//
// Sets the maximum load factor of the `node_hash_set` to the passed value.
//
// NOTE: This overload is provided only for API compatibility with the STL;
// `node_hash_set` will ignore any set load factor and manage its rehashing
// internally as an implementation detail.
using Base::max_load_factor;
// node_hash_set::get_allocator()
//
// Returns the allocator function associated with this `node_hash_set`.
using Base::get_allocator;
// node_hash_set::hash_function()
//
// Returns the hashing function used to hash the keys within this
// `node_hash_set`.
using Base::hash_function;
// node_hash_set::key_eq()
//
// Returns the function used for comparing keys equality.
using Base::key_eq;
};
// erase_if(node_hash_set<>, Pred)
//
// Erases all elements that satisfy the predicate `pred` from the container `c`.
// Returns the number of erased elements.
template <typename T, typename H, typename E, typename A, typename Predicate>
typename node_hash_set<T, H, E, A>::size_type erase_if(
node_hash_set<T, H, E, A>& c, Predicate pred) {
return container_internal::EraseIf(pred, &c);
}
namespace container_internal {
template <class T>
struct NodeHashSetPolicy
: absl::container_internal::node_slot_policy<T&, NodeHashSetPolicy<T>> {
using key_type = T;
using init_type = T;
using constant_iterators = std::true_type;
template <class Allocator, class... Args>
static T* new_element(Allocator* alloc, Args&&... args) {
using ValueAlloc =
typename absl::allocator_traits<Allocator>::template rebind_alloc<T>;
ValueAlloc value_alloc(*alloc);
T* res = absl::allocator_traits<ValueAlloc>::allocate(value_alloc, 1);
absl::allocator_traits<ValueAlloc>::construct(value_alloc, res,
std::forward<Args>(args)...);
return res;
}
template <class Allocator>
static void delete_element(Allocator* alloc, T* elem) {
using ValueAlloc =
typename absl::allocator_traits<Allocator>::template rebind_alloc<T>;
ValueAlloc value_alloc(*alloc);
absl::allocator_traits<ValueAlloc>::destroy(value_alloc, elem);
absl::allocator_traits<ValueAlloc>::deallocate(value_alloc, elem, 1);
}
template <class F, class... Args>
static decltype(absl::container_internal::DecomposeValue(
std::declval<F>(), std::declval<Args>()...))
apply(F&& f, Args&&... args) {
return absl::container_internal::DecomposeValue(
std::forward<F>(f), std::forward<Args>(args)...);
}
static size_t element_space_used(const T*) { return sizeof(T); }
};
} // namespace container_internal
namespace container_algorithm_internal {
// Specialization of trait in absl/algorithm/container.h
template <class Key, class Hash, class KeyEqual, class Allocator>
struct IsUnorderedContainer<absl::node_hash_set<Key, Hash, KeyEqual, Allocator>>
: std::true_type {};
} // namespace container_algorithm_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_NODE_HASH_SET_H_

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// Copyright 2022 The Abseil Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// -----------------------------------------------------------------------------
// File: crc32c.h
// -----------------------------------------------------------------------------
//
// This header file defines the API for computing CRC32C values as checksums
// for arbitrary sequences of bytes provided as a string buffer.
//
// The API includes the basic functions for computing such CRC32C values and
// some utility functions for performing more efficient mathematical
// computations using an existing checksum.
#ifndef ABSL_CRC_CRC32C_H_
#define ABSL_CRC_CRC32C_H_
#include <cstdint>
#include <ostream>
#include "absl/crc/internal/crc32c_inline.h"
#include "absl/strings/str_format.h"
#include "absl/strings/string_view.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
//-----------------------------------------------------------------------------
// crc32c_t
//-----------------------------------------------------------------------------
// `crc32c_t` defines a strongly-typed integer for holding a CRC32C value.
//
// Some operators are intentionally omitted. Only equality operators are defined
// so that `crc32c_t` can be directly compared. Methods for putting `crc32c_t`
// directly into a set are omitted because this is bug-prone due to checksum
// collisions. Use an explicit conversion to the `uint32_t` space for operations
// that treat `crc32c_t` as an integer.
class crc32c_t final {
public:
crc32c_t() = default;
constexpr explicit crc32c_t(uint32_t crc) : crc_(crc) {}
crc32c_t(const crc32c_t&) = default;
crc32c_t& operator=(const crc32c_t&) = default;
explicit operator uint32_t() const { return crc_; }
friend bool operator==(crc32c_t lhs, crc32c_t rhs) {
return static_cast<uint32_t>(lhs) == static_cast<uint32_t>(rhs);
}
friend bool operator!=(crc32c_t lhs, crc32c_t rhs) { return !(lhs == rhs); }
template <typename Sink>
friend void AbslStringify(Sink& sink, crc32c_t crc) {
absl::Format(&sink, "%08x", static_cast<uint32_t>(crc));
}
private:
uint32_t crc_;
};
namespace crc_internal {
// Non-inline code path for `absl::ExtendCrc32c()`. Do not call directly.
// Call `absl::ExtendCrc32c()` (defined below) instead.
crc32c_t ExtendCrc32cInternal(crc32c_t initial_crc,
absl::string_view buf_to_add);
} // namespace crc_internal
// -----------------------------------------------------------------------------
// CRC32C Computation Functions
// -----------------------------------------------------------------------------
// ComputeCrc32c()
//
// Returns the CRC32C value of the provided string.
crc32c_t ComputeCrc32c(absl::string_view buf);
// ExtendCrc32c()
//
// Computes a CRC32C value from an `initial_crc` CRC32C value including the
// `buf_to_add` bytes of an additional buffer. Using this function is more
// efficient than computing a CRC32C value for the combined buffer from
// scratch.
//
// Note: `ExtendCrc32c` with an initial_crc of 0 is equivalent to
// `ComputeCrc32c`.
//
// This operation has a runtime cost of O(`buf_to_add.size()`)
inline crc32c_t ExtendCrc32c(crc32c_t initial_crc,
absl::string_view buf_to_add) {
// Approximately 75% of calls have size <= 64.
if (buf_to_add.size() <= 64) {
uint32_t crc = static_cast<uint32_t>(initial_crc);
if (crc_internal::ExtendCrc32cInline(&crc, buf_to_add.data(),
buf_to_add.size())) {
return crc32c_t{crc};
}
}
return crc_internal::ExtendCrc32cInternal(initial_crc, buf_to_add);
}
// ExtendCrc32cByZeroes()
//
// Computes a CRC32C value for a buffer with an `initial_crc` CRC32C value,
// where `length` bytes with a value of 0 are appended to the buffer. Using this
// function is more efficient than computing a CRC32C value for the combined
// buffer from scratch.
//
// This operation has a runtime cost of O(log(`length`))
crc32c_t ExtendCrc32cByZeroes(crc32c_t initial_crc, size_t length);
// MemcpyCrc32c()
//
// Copies `src` to `dest` using `memcpy()` semantics, returning the CRC32C
// value of the copied buffer.
//
// Using `MemcpyCrc32c()` is potentially faster than performing the `memcpy()`
// and `ComputeCrc32c()` operations separately.
crc32c_t MemcpyCrc32c(void* dest, const void* src, size_t count,
crc32c_t initial_crc = crc32c_t{0});
// -----------------------------------------------------------------------------
// CRC32C Arithmetic Functions
// -----------------------------------------------------------------------------
// The following functions perform arithmetic on CRC32C values, which are
// generally more efficient than recalculating any given result's CRC32C value.
// ConcatCrc32c()
//
// Calculates the CRC32C value of two buffers with known CRC32C values
// concatenated together.
//
// Given a buffer with CRC32C value `crc1` and a buffer with
// CRC32C value `crc2` and length, `crc2_length`, returns the CRC32C value of
// the concatenation of these two buffers.
//
// This operation has a runtime cost of O(log(`crc2_length`)).
crc32c_t ConcatCrc32c(crc32c_t crc1, crc32c_t crc2, size_t crc2_length);
// RemoveCrc32cPrefix()
//
// Calculates the CRC32C value of an existing buffer with a series of bytes
// (the prefix) removed from the beginning of that buffer.
//
// Given the CRC32C value of an existing buffer, `full_string_crc`; The CRC32C
// value of a prefix of that buffer, `prefix_crc`; and the length of the buffer
// with the prefix removed, `remaining_string_length` , return the CRC32C
// value of the buffer with the prefix removed.
//
// This operation has a runtime cost of O(log(`remaining_string_length`)).
crc32c_t RemoveCrc32cPrefix(crc32c_t prefix_crc, crc32c_t full_string_crc,
size_t remaining_string_length);
// RemoveCrc32cSuffix()
//
// Calculates the CRC32C value of an existing buffer with a series of bytes
// (the suffix) removed from the end of that buffer.
//
// Given a CRC32C value of an existing buffer `full_string_crc`, the CRC32C
// value of the suffix to remove `suffix_crc`, and the length of that suffix
// `suffix_len`, returns the CRC32C value of the buffer with suffix removed.
//
// This operation has a runtime cost of O(log(`suffix_len`))
crc32c_t RemoveCrc32cSuffix(crc32c_t full_string_crc, crc32c_t suffix_crc,
size_t suffix_length);
// operator<<
//
// Streams the CRC32C value `crc` to the stream `os`.
inline std::ostream& operator<<(std::ostream& os, crc32c_t crc) {
return os << absl::StreamFormat("%08x", static_cast<uint32_t>(crc));
}
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CRC_CRC32C_H_

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// Copyright 2022 The Abseil Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CRC_INTERNAL_CPU_DETECT_H_
#define ABSL_CRC_INTERNAL_CPU_DETECT_H_
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace crc_internal {
// Enumeration of architectures that we have special-case tuning parameters for.
// This set may change over time.
enum class CpuType {
kUnknown,
kIntelHaswell,
kAmdRome,
kAmdNaples,
kAmdMilan,
kAmdGenoa,
kAmdRyzenV3000,
kIntelCascadelakeXeon,
kIntelSkylakeXeon,
kIntelBroadwell,
kIntelSkylake,
kIntelIvybridge,
kIntelSandybridge,
kIntelWestmere,
kArmNeoverseN1,
kArmNeoverseV1,
kAmpereSiryn,
kArmNeoverseN2,
kArmNeoverseV2
};
// Returns the type of host CPU this code is running on. Returns kUnknown if
// the host CPU is of unknown type, or if detection otherwise fails.
CpuType GetCpuType();
// Returns whether the host CPU supports the CPU features needed for our
// accelerated implementations. The CpuTypes enumerated above apart from
// kUnknown support the required features. On unknown CPUs, we can use
// this to see if it's safe to use hardware acceleration, though without any
// tuning.
bool SupportsArmCRC32PMULL();
} // namespace crc_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CRC_INTERNAL_CPU_DETECT_H_

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// Copyright 2022 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CRC_INTERNAL_CRC_H_
#define ABSL_CRC_INTERNAL_CRC_H_
#include <cstdint>
#include "absl/base/config.h"
// This class implements CRCs (aka Rabin Fingerprints).
// Treats the input as a polynomial with coefficients in Z(2),
// and finds the remainder when divided by an primitive polynomial
// of the appropriate length.
// A polynomial is represented by the bit pattern formed by its coefficients,
// but with the highest order bit not stored.
// The highest degree coefficient is stored in the lowest numbered bit
// in the lowest addressed byte. Thus, in what follows, the highest degree
// coefficient that is stored is in the low order bit of "lo" or "*lo".
// Hardware acceleration is used when available.
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace crc_internal {
class CRC {
public:
virtual ~CRC();
// If "*crc" is the CRC of bytestring A, place the CRC of
// the bytestring formed from the concatenation of A and the "length"
// bytes at "bytes" into "*crc".
virtual void Extend(uint32_t* crc, const void* bytes,
size_t length) const = 0;
// Equivalent to Extend(crc, bytes, length) where "bytes"
// points to an array of "length" zero bytes.
virtual void ExtendByZeroes(uint32_t* crc, size_t length) const = 0;
// Inverse operation of ExtendByZeroes. If `crc` is the CRC value of a string
// ending in `length` zero bytes, this returns a CRC value of that string
// with those zero bytes removed.
virtual void UnextendByZeroes(uint32_t* crc, size_t length) const = 0;
// Apply a non-linear transformation to "*crc" so that
// it is safe to CRC the result with the same polynomial without
// any reduction of error-detection ability in the outer CRC.
// Unscramble() performs the inverse transformation.
// It is strongly recommended that CRCs be scrambled before storage or
// transmission, and unscrambled at the other end before further manipulation.
virtual void Scramble(uint32_t* crc) const = 0;
virtual void Unscramble(uint32_t* crc) const = 0;
// Crc32c() returns the singleton implementation of CRC for the CRC32C
// polynomial. Returns a handle that MUST NOT be destroyed with delete.
static CRC* Crc32c();
protected:
CRC(); // Clients may not call constructor; use Crc32c() instead.
private:
CRC(const CRC&) = delete;
CRC& operator=(const CRC&) = delete;
};
} // namespace crc_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CRC_INTERNAL_CRC_H_

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