xref: /minix3/external/bsd/libc++/dist/libcxx/src/condition_variable.cpp (revision eda6f5931d42c77e1480347b1fc3eef2f8d33806)
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 _LIBCPP_BEGIN_NAMESPACE_STD
16 
17 condition_variable::~condition_variable()
18 {
19     pthread_cond_destroy(&__cv_);
20 }
21 
22 void
23 condition_variable::notify_one() _NOEXCEPT
24 {
25     pthread_cond_signal(&__cv_);
26 }
27 
28 void
29 condition_variable::notify_all() _NOEXCEPT
30 {
31     pthread_cond_broadcast(&__cv_);
32 }
33 
34 void
35 condition_variable::wait(unique_lock<mutex>& lk)
36 {
37     if (!lk.owns_lock())
38         __throw_system_error(EPERM,
39                                   "condition_variable::wait: mutex not locked");
40     int ec = pthread_cond_wait(&__cv_, lk.mutex()->native_handle());
41     if (ec)
42         __throw_system_error(ec, "condition_variable wait failed");
43 }
44 
45 void
46 condition_variable::__do_timed_wait(unique_lock<mutex>& lk,
47                chrono::time_point<chrono::system_clock, chrono::nanoseconds> tp)
48 {
49 #if !defined(__minix) /* LSC: FIXME a loop with yield plus sleep? */
50     using namespace chrono;
51     if (!lk.owns_lock())
52         __throw_system_error(EPERM,
53                             "condition_variable::timed wait: mutex not locked");
54     nanoseconds d = tp.time_since_epoch();
55     if (d > nanoseconds(0x59682F000000E941))
56         d = nanoseconds(0x59682F000000E941);
57     timespec ts;
58     seconds s = duration_cast<seconds>(d);
59     typedef decltype(ts.tv_sec) ts_sec;
60     _LIBCPP_CONSTEXPR ts_sec ts_sec_max = numeric_limits<ts_sec>::max();
61     if (s.count() < ts_sec_max)
62     {
63         ts.tv_sec = static_cast<ts_sec>(s.count());
64         ts.tv_nsec = static_cast<decltype(ts.tv_nsec)>((d - s).count());
65     }
66     else
67     {
68         ts.tv_sec = ts_sec_max;
69         ts.tv_nsec = giga::num - 1;
70     }
71     int ec = pthread_cond_timedwait(&__cv_, lk.mutex()->native_handle(), &ts);
72     if (ec != 0 && ec != ETIMEDOUT)
73 #else
74     int ec = EINVAL;
75 #endif /* !defined(__minix) */
76         __throw_system_error(ec, "condition_variable timed_wait failed");
77 }
78 
79 void
80 notify_all_at_thread_exit(condition_variable& cond, unique_lock<mutex> lk)
81 {
82     __thread_local_data()->notify_all_at_thread_exit(&cond, lk.release());
83 }
84 
85 _LIBCPP_END_NAMESPACE_STD
86