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