1 //===-------------------- condition_variable.cpp --------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "condition_variable"
11 #include "thread"
12 #include "system_error"
13 #include "cassert"
14 
15 #if !_LIBCPP_SINGLE_THREADED
16 
17 _LIBCPP_BEGIN_NAMESPACE_STD
18 
~condition_variable()19 condition_variable::~condition_variable()
20 {
21     pthread_cond_destroy(&__cv_);
22 }
23 
24 void
notify_one()25 condition_variable::notify_one() _NOEXCEPT
26 {
27     pthread_cond_signal(&__cv_);
28 }
29 
30 void
notify_all()31 condition_variable::notify_all() _NOEXCEPT
32 {
33     pthread_cond_broadcast(&__cv_);
34 }
35 
36 void
wait(unique_lock<mutex> & lk)37 condition_variable::wait(unique_lock<mutex>& lk) _NOEXCEPT
38 {
39     if (!lk.owns_lock())
40         __throw_system_error(EPERM,
41                                   "condition_variable::wait: mutex not locked");
42     int ec = pthread_cond_wait(&__cv_, lk.mutex()->native_handle());
43     if (ec)
44         __throw_system_error(ec, "condition_variable wait failed");
45 }
46 
47 void
__do_timed_wait(unique_lock<mutex> & lk,chrono::time_point<chrono::system_clock,chrono::nanoseconds> tp)48 condition_variable::__do_timed_wait(unique_lock<mutex>& lk,
49      chrono::time_point<chrono::system_clock, chrono::nanoseconds> tp) _NOEXCEPT
50 {
51     using namespace chrono;
52     if (!lk.owns_lock())
53         __throw_system_error(EPERM,
54                             "condition_variable::timed wait: mutex not locked");
55     nanoseconds d = tp.time_since_epoch();
56     if (d > nanoseconds(0x59682F000000E941))
57         d = nanoseconds(0x59682F000000E941);
58     timespec ts;
59     seconds s = duration_cast<seconds>(d);
60     typedef decltype(ts.tv_sec) ts_sec;
61     _LIBCPP_CONSTEXPR ts_sec ts_sec_max = numeric_limits<ts_sec>::max();
62     if (s.count() < ts_sec_max)
63     {
64         ts.tv_sec = static_cast<ts_sec>(s.count());
65         ts.tv_nsec = static_cast<decltype(ts.tv_nsec)>((d - s).count());
66     }
67     else
68     {
69         ts.tv_sec = ts_sec_max;
70         ts.tv_nsec = giga::num - 1;
71     }
72     int ec = pthread_cond_timedwait(&__cv_, lk.mutex()->native_handle(), &ts);
73     if (ec != 0 && ec != ETIMEDOUT)
74         __throw_system_error(ec, "condition_variable timed_wait failed");
75 }
76 
77 void
notify_all_at_thread_exit(condition_variable & cond,unique_lock<mutex> lk)78 notify_all_at_thread_exit(condition_variable& cond, unique_lock<mutex> lk)
79 {
80     __thread_local_data()->notify_all_at_thread_exit(&cond, lk.release());
81 }
82 
83 _LIBCPP_END_NAMESPACE_STD
84 
85 #endif // !_LIBCPP_SINGLE_THREADED
86 
87