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 <__availability>
14 #include <__config>
15 #include <__stop_token/intrusive_shared_ptr.h>
16 #include <__stop_token/stop_state.h>
17 
18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19 #  pragma GCC system_header
20 #endif
21 
22 _LIBCPP_BEGIN_NAMESPACE_STD
23 
24 #if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN)
25 
26 class _LIBCPP_AVAILABILITY_SYNC stop_token {
27 public:
28   _LIBCPP_HIDE_FROM_ABI stop_token() noexcept = default;
29 
30   _LIBCPP_HIDE_FROM_ABI stop_token(const stop_token&) noexcept            = default;
31   _LIBCPP_HIDE_FROM_ABI stop_token(stop_token&&) noexcept                 = default;
32   _LIBCPP_HIDE_FROM_ABI stop_token& operator=(const stop_token&) noexcept = default;
33   _LIBCPP_HIDE_FROM_ABI stop_token& operator=(stop_token&&) noexcept      = default;
34   _LIBCPP_HIDE_FROM_ABI ~stop_token()                                     = default;
35 
36   _LIBCPP_HIDE_FROM_ABI void swap(stop_token& __other) noexcept { __state_.swap(__other.__state_); }
37 
38   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_requested() const noexcept {
39     return __state_ != nullptr && __state_->__stop_requested();
40   }
41 
42   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool stop_possible() const noexcept {
43     return __state_ != nullptr && __state_->__stop_possible_for_stop_token();
44   }
45 
46   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI friend bool operator==(const stop_token&, const stop_token&) noexcept = default;
47 
48   _LIBCPP_HIDE_FROM_ABI friend void swap(stop_token& __lhs, stop_token& __rhs) noexcept { __lhs.swap(__rhs); }
49 
50 private:
51   __intrusive_shared_ptr<__stop_state> __state_;
52 
53   friend class stop_source;
54   template <class _Tp>
55   friend class stop_callback;
56 
57   _LIBCPP_HIDE_FROM_ABI explicit stop_token(const __intrusive_shared_ptr<__stop_state>& __state) : __state_(__state) {}
58 };
59 
60 #endif // _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_STOP_TOKEN)
61 
62 _LIBCPP_END_NAMESPACE_STD
63 
64 #endif // _LIBCPP___STOP_TOKEN_STOP_TOKEN_H
65