Home | History | Annotate | Download | only in src
      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) _NOEXCEPT
     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) _NOEXCEPT
     48 {
     49     using namespace chrono;
     50     if (!lk.owns_lock())
     51         __throw_system_error(EPERM,
     52                             "condition_variable::timed wait: mutex not locked");
     53     nanoseconds d = tp.time_since_epoch();
     54     if (d > nanoseconds(0x59682F000000E941))
     55         d = nanoseconds(0x59682F000000E941);
     56     timespec ts;
     57     seconds s = duration_cast<seconds>(d);
     58     typedef decltype(ts.tv_sec) ts_sec;
     59     _LIBCPP_CONSTEXPR ts_sec ts_sec_max = numeric_limits<ts_sec>::max();
     60     if (s.count() < ts_sec_max)
     61     {
     62         ts.tv_sec = static_cast<ts_sec>(s.count());
     63         ts.tv_nsec = static_cast<decltype(ts.tv_nsec)>((d - s).count());
     64     }
     65     else
     66     {
     67         ts.tv_sec = ts_sec_max;
     68         ts.tv_nsec = giga::num - 1;
     69     }
     70     int ec = pthread_cond_timedwait(&__cv_, lk.mutex()->native_handle(), &ts);
     71     if (ec != 0 && ec != ETIMEDOUT)
     72         __throw_system_error(ec, "condition_variable timed_wait failed");
     73 }
     74 
     75 void
     76 notify_all_at_thread_exit(condition_variable& cond, unique_lock<mutex> lk)
     77 {
     78     __thread_local_data()->notify_all_at_thread_exit(&cond, lk.release());
     79 }
     80 
     81 _LIBCPP_END_NAMESPACE_STD
     82