libcxx/include/__cxx03/__stop_token/stop_token.h

   1 // -*- C++ -*-
   2 //===----------------------------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef _LIBCPP___STOP_TOKEN_STOP_TOKEN_H
  11 #define _LIBCPP___STOP_TOKEN_STOP_TOKEN_H
  12
  13 #include <__cxx03/__config>
  14 #include <__cxx03/__stop_token/intrusive_shared_ptr.h>
  15 #include <__cxx03/__stop_token/stop_state.h>
  16
  17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  18 #  pragma GCC system_header
  19 #endif
  20
  21 _LIBCPP_BEGIN_NAMESPACE_STD
  22
  23 #if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
  24
  25 class _LIBCPP_AVAILABILITY_SYNC stop_token {
  26 public:
  27   _LIBCPP_HIDE_FROM_ABI stop_token() noexcept = default;
  28
  29   _LIBCPP_HIDE_FROM_ABI stop_token(const stop_token&) noexcept            = default;
  30   _LIBCPP_HIDE_FROM_ABI stop_token(stop_token&&) noexcept                 = default;
  31   _LIBCPP_HIDE_FROM_ABI stop_token& operator=(const stop_token&) noexcept = default;
  32   _LIBCPP_HIDE_FROM_ABI stop_token& operator=(stop_token&&) noexcept      = default;
  33   _LIBCPP_HIDE_FROM_ABI ~stop_token()                                     = default;
  34
  35   _LIBCPP_HIDE_FROM_ABI void swap(stop_token& __other) noexcept { __state_.swap(__other.__state_); }
  36
  37   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_requested() const noexcept {
  38     return __state_ != nullptr && __state_->__stop_requested();
  39   }
  40
  41   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_possible() const noexcept {
  42     return __state_ != nullptr && __state_->__stop_possible_for_stop_token();
  43   }
  44
  45   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI friend bool operator==(const stop_token&, const stop_token&) noexcept = default;
  46
  47   _LIBCPP_HIDE_FROM_ABI friend void swap(stop_token& __lhs, stop_token& __rhs) noexcept { __lhs.swap(__rhs); }
  48
  49 private:
  50   __intrusive_shared_ptr<__stop_state> __state_;
  51
  52   friend class stop_source;
  53   template <class _Tp>
  54   friend class stop_callback;
  55
  56   _LIBCPP_HIDE_FROM_ABI explicit stop_token(const __intrusive_shared_ptr<__stop_state>& __state) : __state_(__state) {}
  57 };
  58
  59 #endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN) && !defined(_LIBCPP_HAS_NO_THREADS)
  60
  61 _LIBCPP_END_NAMESPACE_STD
  62
  63 #endif // _LIBCPP___STOP_TOKEN_STOP_TOKEN_H