1 | // std::this_thread::sleep_for/until declarations -*- C++ -*- |
2 | |
3 | // Copyright (C) 2008-2021 Free Software Foundation, Inc. |
4 | // |
5 | // This file is part of the GNU ISO C++ Library. This library is free |
6 | // software; you can redistribute it and/or modify it under the |
7 | // terms of the GNU General Public License as published by the |
8 | // Free Software Foundation; either version 3, or (at your option) |
9 | // any later version. |
10 | |
11 | // This library is distributed in the hope that it will be useful, |
12 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
14 | // GNU General Public License for more details. |
15 | |
16 | // Under Section 7 of GPL version 3, you are granted additional |
17 | // permissions described in the GCC Runtime Library Exception, version |
18 | // 3.1, as published by the Free Software Foundation. |
19 | |
20 | // You should have received a copy of the GNU General Public License and |
21 | // a copy of the GCC Runtime Library Exception along with this program; |
22 | // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
23 | // <http://www.gnu.org/licenses/>. |
24 | |
25 | /** @file bits/this_thread_sleep.h |
26 | * This is an internal header file, included by other library headers. |
27 | * Do not attempt to use it directly. @headername{thread} |
28 | */ |
29 | |
30 | #ifndef _GLIBCXX_THIS_THREAD_SLEEP_H |
31 | #define _GLIBCXX_THIS_THREAD_SLEEP_H 1 |
32 | |
33 | #pragma GCC system_header |
34 | |
35 | #if __cplusplus >= 201103L |
36 | #include <bits/c++config.h> |
37 | |
38 | #include <chrono> // std::chrono::* |
39 | |
40 | #ifdef _GLIBCXX_USE_NANOSLEEP |
41 | # include <cerrno> // errno, EINTR |
42 | # include <time.h> // nanosleep |
43 | #endif |
44 | |
45 | namespace std _GLIBCXX_VISIBILITY(default) |
46 | { |
47 | _GLIBCXX_BEGIN_NAMESPACE_VERSION |
48 | |
49 | /** @addtogroup threads |
50 | * @{ |
51 | */ |
52 | |
53 | /** @namespace std::this_thread |
54 | * @brief ISO C++ 2011 namespace for interacting with the current thread |
55 | * |
56 | * C++11 30.3.2 [thread.thread.this] Namespace this_thread. |
57 | */ |
58 | namespace this_thread |
59 | { |
60 | #ifndef _GLIBCXX_NO_SLEEP |
61 | |
62 | #ifndef _GLIBCXX_USE_NANOSLEEP |
63 | void |
64 | __sleep_for(chrono::seconds, chrono::nanoseconds); |
65 | #endif |
66 | |
67 | /// this_thread::sleep_for |
68 | template<typename _Rep, typename _Period> |
69 | inline void |
70 | sleep_for(const chrono::duration<_Rep, _Period>& __rtime) |
71 | { |
72 | if (__rtime <= __rtime.zero()) |
73 | return; |
74 | auto __s = chrono::duration_cast<chrono::seconds>(__rtime); |
75 | auto __ns = chrono::duration_cast<chrono::nanoseconds>(__rtime - __s); |
76 | #ifdef _GLIBCXX_USE_NANOSLEEP |
77 | struct ::timespec __ts = |
78 | { |
79 | .tv_sec: static_cast<std::time_t>(__s.count()), |
80 | .tv_nsec: static_cast<long>(__ns.count()) |
81 | }; |
82 | while (::nanosleep(requested_time: &__ts, remaining: &__ts) == -1 && errno == EINTR) |
83 | { } |
84 | #else |
85 | __sleep_for(__s, __ns); |
86 | #endif |
87 | } |
88 | |
89 | /// this_thread::sleep_until |
90 | template<typename _Clock, typename _Duration> |
91 | inline void |
92 | sleep_until(const chrono::time_point<_Clock, _Duration>& __atime) |
93 | { |
94 | #if __cplusplus > 201703L |
95 | static_assert(chrono::is_clock_v<_Clock>); |
96 | #endif |
97 | auto __now = _Clock::now(); |
98 | if (_Clock::is_steady) |
99 | { |
100 | if (__now < __atime) |
101 | sleep_for(__atime - __now); |
102 | return; |
103 | } |
104 | while (__now < __atime) |
105 | { |
106 | sleep_for(__atime - __now); |
107 | __now = _Clock::now(); |
108 | } |
109 | } |
110 | #endif // ! NO_SLEEP |
111 | } // namespace this_thread |
112 | |
113 | /// @} |
114 | |
115 | _GLIBCXX_END_NAMESPACE_VERSION |
116 | } // namespace |
117 | #endif // C++11 |
118 | |
119 | #endif // _GLIBCXX_THIS_THREAD_SLEEP_H |
120 | |