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Edit File: semaphore
// <semaphore> -*- C++ -*- // Copyright (C) 2020-2021 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the // terms of the GNU General Public License as published by the // Free Software Foundation; either version 3, or (at your option) // any later version. // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // Under Section 7 of GPL version 3, you are granted additional // permissions described in the GCC Runtime Library Exception, version // 3.1, as published by the Free Software Foundation. // You should have received a copy of the GNU General Public License and // a copy of the GCC Runtime Library Exception along with this program; // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see // <http://www.gnu.org/licenses/>. /** @file include/semaphore * This is a Standard C++ Library header. */ #ifndef _GLIBCXX_SEMAPHORE #define _GLIBCXX_SEMAPHORE 1 #pragma GCC system_header #if __cplusplus > 201703L #include <bits/semaphore_base.h> #if __cpp_lib_atomic_wait || _GLIBCXX_HAVE_POSIX_SEMAPHORE namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION #define __cpp_lib_semaphore 201907L template<ptrdiff_t __least_max_value = __semaphore_impl::_S_max> class counting_semaphore { static_assert(__least_max_value >= 0); static_assert(__least_max_value <= __semaphore_impl::_S_max); __semaphore_impl _M_sem; public: explicit counting_semaphore(ptrdiff_t __desired) noexcept : _M_sem(__desired) { } ~counting_semaphore() = default; counting_semaphore(const counting_semaphore&) = delete; counting_semaphore& operator=(const counting_semaphore&) = delete; static constexpr ptrdiff_t max() noexcept { return __least_max_value; } void release(ptrdiff_t __update = 1) noexcept(noexcept(_M_sem._M_release(1))) { _M_sem._M_release(__update); } void acquire() noexcept(noexcept(_M_sem._M_acquire())) { _M_sem._M_acquire(); } bool try_acquire() noexcept(noexcept(_M_sem._M_try_acquire())) { return _M_sem._M_try_acquire(); } template<typename _Rep, typename _Period> bool try_acquire_for(const std::chrono::duration<_Rep, _Period>& __rtime) { return _M_sem._M_try_acquire_for(__rtime); } template<typename _Clock, typename _Dur> bool try_acquire_until(const std::chrono::time_point<_Clock, _Dur>& __atime) { return _M_sem._M_try_acquire_until(__atime); } }; using binary_semaphore = std::counting_semaphore<1>; _GLIBCXX_END_NAMESPACE_VERSION } // namespace #endif // cpp_lib_atomic_wait || _GLIBCXX_HAVE_POSIX_SEMAPHORE #endif // C++20 #endif // _GLIBCXX_SEMAPHORE