__cxx03/__stop_token/stop_token.h

0001 // -*- C++ -*-
0002 //===----------------------------------------------------------------------===//
0003 //
0004 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0005 // See https://llvm.org/LICENSE.txt for license information.
0006 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0007 //
0008 //===----------------------------------------------------------------------===//
0009
0010 #ifndef _LIBCPP___CXX03___STOP_TOKEN_STOP_TOKEN_H
0011 #define _LIBCPP___CXX03___STOP_TOKEN_STOP_TOKEN_H
0012
0013 #include <__cxx03/__config>
0014 #include <__cxx03/__stop_token/intrusive_shared_ptr.h>
0015 #include <__cxx03/__stop_token/stop_state.h>
0016
0017 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0018 #  pragma GCC system_header
0019 #endif
0020
0021 _LIBCPP_BEGIN_NAMESPACE_STD
0022
0023 #if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
0024
0025 class _LIBCPP_AVAILABILITY_SYNC stop_token {
0026 public:
0027   _LIBCPP_HIDE_FROM_ABI stop_token() noexcept = default;
0028
0029   _LIBCPP_HIDE_FROM_ABI stop_token(const stop_token&) noexcept            = default;
0030   _LIBCPP_HIDE_FROM_ABI stop_token(stop_token&&) noexcept                 = default;
0031   _LIBCPP_HIDE_FROM_ABI stop_token& operator=(const stop_token&) noexcept = default;
0032   _LIBCPP_HIDE_FROM_ABI stop_token& operator=(stop_token&&) noexcept      = default;
0033   _LIBCPP_HIDE_FROM_ABI ~stop_token()                                     = default;
0034
0035   _LIBCPP_HIDE_FROM_ABI void swap(stop_token& __other) noexcept { __state_.swap(__other.__state_); }
0036
0037   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_requested() const noexcept {
0038     return __state_ != nullptr && __state_->__stop_requested();
0039   }
0040
0041   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_possible() const noexcept {
0042     return __state_ != nullptr && __state_->__stop_possible_for_stop_token();
0043   }
0044
0045   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI friend bool operator==(const stop_token&, const stop_token&) noexcept = default;
0046
0047   _LIBCPP_HIDE_FROM_ABI friend void swap(stop_token& __lhs, stop_token& __rhs) noexcept { __lhs.swap(__rhs); }
0048
0049 private:
0050   __intrusive_shared_ptr<__stop_state> __state_;
0051
0052   friend class stop_source;
0053   template <class _Tp>
0054   friend class stop_callback;
0055
0056   _LIBCPP_HIDE_FROM_ABI explicit stop_token(const __intrusive_shared_ptr<__stop_state>& __state) : __state_(__state) {}
0057 };
0058
0059 #endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
0060
0061 _LIBCPP_END_NAMESPACE_STD
0062
0063 #endif // _LIBCPP___CXX03___STOP_TOKEN_STOP_TOKEN_H