| 1 | //===-------------------- condition_variable.cpp --------------------------===// |
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #include "__config" |
| 10 | |
| 11 | #ifndef _LIBCPP_HAS_NO_THREADS |
| 12 | |
| 13 | #include "condition_variable" |
| 14 | #include "thread" |
| 15 | #include "system_error" |
| 16 | #include "__undef_macros" |
| 17 | |
| 18 | #if defined(__unix__) && defined(__ELF__) && defined(_LIBCPP_HAS_COMMENT_LIB_PRAGMA) |
| 19 | #pragma comment(lib, "pthread") |
| 20 | #endif |
| 21 | |
| 22 | _LIBCPP_BEGIN_NAMESPACE_STD |
| 23 | |
| 24 | // ~condition_variable is defined elsewhere. |
| 25 | |
| 26 | void |
| 27 | condition_variable::notify_one() _NOEXCEPT |
| 28 | { |
| 29 | __libcpp_condvar_signal(&__cv_); |
| 30 | } |
| 31 | |
| 32 | void |
| 33 | condition_variable::notify_all() _NOEXCEPT |
| 34 | { |
| 35 | __libcpp_condvar_broadcast(&__cv_); |
| 36 | } |
| 37 | |
| 38 | void |
| 39 | condition_variable::wait(unique_lock<mutex>& lk) _NOEXCEPT |
| 40 | { |
| 41 | if (!lk.owns_lock()) |
| 42 | __throw_system_error(EPERM, |
| 43 | "condition_variable::wait: mutex not locked" ); |
| 44 | int ec = __libcpp_condvar_wait(&__cv_, lk.mutex()->native_handle()); |
| 45 | if (ec) |
| 46 | __throw_system_error(ec, "condition_variable wait failed" ); |
| 47 | } |
| 48 | |
| 49 | void |
| 50 | condition_variable::__do_timed_wait(unique_lock<mutex>& lk, |
| 51 | chrono::time_point<chrono::system_clock, chrono::nanoseconds> tp) _NOEXCEPT |
| 52 | { |
| 53 | using namespace chrono; |
| 54 | if (!lk.owns_lock()) |
| 55 | __throw_system_error(EPERM, |
| 56 | "condition_variable::timed wait: mutex not locked" ); |
| 57 | nanoseconds d = tp.time_since_epoch(); |
| 58 | if (d > nanoseconds(0x59682F000000E941)) |
| 59 | d = nanoseconds(0x59682F000000E941); |
| 60 | __libcpp_timespec_t ts; |
| 61 | seconds s = duration_cast<seconds>(d); |
| 62 | typedef decltype(ts.tv_sec) ts_sec; |
| 63 | _LIBCPP_CONSTEXPR ts_sec ts_sec_max = numeric_limits<ts_sec>::max(); |
| 64 | if (s.count() < ts_sec_max) |
| 65 | { |
| 66 | ts.tv_sec = static_cast<ts_sec>(s.count()); |
| 67 | ts.tv_nsec = static_cast<decltype(ts.tv_nsec)>((d - s).count()); |
| 68 | } |
| 69 | else |
| 70 | { |
| 71 | ts.tv_sec = ts_sec_max; |
| 72 | ts.tv_nsec = giga::num - 1; |
| 73 | } |
| 74 | int ec = __libcpp_condvar_timedwait(&__cv_, lk.mutex()->native_handle(), &ts); |
| 75 | if (ec != 0 && ec != ETIMEDOUT) |
| 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 | auto& tl_ptr = __thread_local_data(); |
| 83 | // If this thread was not created using std::thread then it will not have |
| 84 | // previously allocated. |
| 85 | if (tl_ptr.get() == nullptr) { |
| 86 | tl_ptr.set_pointer(new __thread_struct); |
| 87 | } |
| 88 | __thread_local_data()->notify_all_at_thread_exit(&cond, lk.release()); |
| 89 | } |
| 90 | |
| 91 | _LIBCPP_END_NAMESPACE_STD |
| 92 | |
| 93 | #endif // !_LIBCPP_HAS_NO_THREADS |
| 94 | |