external/bsd/libc++/dist/libcxx/src/condition_variable.cpp

   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