]>
Commit | Line | Data |
---|---|---|
1 | // condition_variable -*- C++ -*- | |
2 | ||
3 | // Copyright (C) 2008-2024 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 | #include <condition_variable> | |
26 | #include <cstdlib> | |
27 | ||
28 | #ifdef _GLIBCXX_HAS_GTHREADS | |
29 | ||
30 | namespace std _GLIBCXX_VISIBILITY(default) | |
31 | { | |
32 | _GLIBCXX_BEGIN_NAMESPACE_VERSION | |
33 | ||
34 | condition_variable::condition_variable() noexcept = default; | |
35 | ||
36 | condition_variable::~condition_variable() noexcept = default; | |
37 | ||
38 | void | |
39 | condition_variable::wait(unique_lock<mutex>& __lock) | |
40 | { | |
41 | _M_cond.wait(*__lock.mutex()); | |
42 | } | |
43 | ||
44 | void | |
45 | condition_variable::notify_one() noexcept | |
46 | { | |
47 | _M_cond.notify_one(); | |
48 | } | |
49 | ||
50 | void | |
51 | condition_variable::notify_all() noexcept | |
52 | { | |
53 | _M_cond.notify_all(); | |
54 | } | |
55 | ||
56 | extern void | |
57 | __at_thread_exit(__at_thread_exit_elt*); | |
58 | ||
59 | namespace | |
60 | { | |
61 | __gthread_key_t key; | |
62 | ||
63 | void run(void* p) | |
64 | { | |
65 | auto elt = (__at_thread_exit_elt*)p; | |
66 | while (elt) | |
67 | { | |
68 | auto next = elt->_M_next; | |
69 | elt->_M_cb(elt); | |
70 | elt = next; | |
71 | } | |
72 | } | |
73 | ||
74 | void run() | |
75 | { | |
76 | auto elt = (__at_thread_exit_elt*)__gthread_getspecific(key); | |
77 | __gthread_setspecific(key, nullptr); | |
78 | run(elt); | |
79 | } | |
80 | ||
81 | struct notifier final : __at_thread_exit_elt | |
82 | { | |
83 | notifier(condition_variable& cv, unique_lock<mutex>& l) | |
84 | : cv(&cv), mx(l.release()) | |
85 | { | |
86 | _M_cb = ¬ifier::run; | |
87 | __at_thread_exit(this); | |
88 | } | |
89 | ||
90 | ~notifier() | |
91 | { | |
92 | mx->unlock(); | |
93 | cv->notify_all(); | |
94 | } | |
95 | ||
96 | condition_variable* cv; | |
97 | mutex* mx; | |
98 | ||
99 | static void run(void* p) { delete static_cast<notifier*>(p); } | |
100 | }; | |
101 | ||
102 | ||
103 | void key_init() { | |
104 | struct key_s { | |
105 | key_s() { __gthread_key_create (&key, run); } | |
106 | ~key_s() { __gthread_key_delete (key); } | |
107 | }; | |
108 | static key_s ks; | |
109 | // Also make sure the callbacks are run by std::exit. | |
110 | std::atexit (run); | |
111 | } | |
112 | } | |
113 | ||
114 | void | |
115 | __at_thread_exit(__at_thread_exit_elt* elt) | |
116 | { | |
117 | static __gthread_once_t once = __GTHREAD_ONCE_INIT; | |
118 | __gthread_once (&once, key_init); | |
119 | ||
120 | elt->_M_next = (__at_thread_exit_elt*)__gthread_getspecific(key); | |
121 | __gthread_setspecific(key, elt); | |
122 | } | |
123 | ||
124 | void | |
125 | notify_all_at_thread_exit(condition_variable& cv, unique_lock<mutex> l) | |
126 | { | |
127 | (void) new notifier{cv, l}; | |
128 | } | |
129 | ||
130 | _GLIBCXX_END_NAMESPACE_VERSION | |
131 | } // namespace | |
132 | ||
133 | #endif // _GLIBCXX_HAS_GTHREADS |