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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___CONDITION_VARIABLE_CONDITION_VARIABLE_H
#define _LIBCPP___CONDITION_VARIABLE_CONDITION_VARIABLE_H
#include <__chrono/steady_clock.h>
#include <__chrono/system_clock.h>
#include <__chrono/time_point.h>
#include <__config>
#include <__mutex/mutex.h>
#include <__mutex/unique_lock.h>
#include <__system_error/system_error.h>
#include <__threading_support>
#include <__type_traits/enable_if.h>
#include <__type_traits/is_floating_point.h>
#include <__utility/move.h>
#include <limits>
#include <ratio>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
#ifndef _LIBCPP_HAS_NO_THREADS
// enum class cv_status
_LIBCPP_DECLARE_STRONG_ENUM(cv_status){no_timeout, timeout};
_LIBCPP_DECLARE_STRONG_ENUM_EPILOG(cv_status)
class _LIBCPP_EXPORTED_FROM_ABI condition_variable {
__libcpp_condvar_t __cv_ = _LIBCPP_CONDVAR_INITIALIZER;
public:
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR condition_variable() _NOEXCEPT = default;
# ifdef _LIBCPP_HAS_TRIVIAL_CONDVAR_DESTRUCTION
~condition_variable() = default;
# else
~condition_variable();
# endif
condition_variable(const condition_variable&) = delete;
condition_variable& operator=(const condition_variable&) = delete;
void notify_one() _NOEXCEPT;
void notify_all() _NOEXCEPT;
void wait(unique_lock<mutex>& __lk) _NOEXCEPT;
template <class _Predicate>
_LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS void wait(unique_lock<mutex>& __lk, _Predicate __pred);
template <class _Clock, class _Duration>
_LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS cv_status
wait_until(unique_lock<mutex>& __lk, const chrono::time_point<_Clock, _Duration>& __t);
template <class _Clock, class _Duration, class _Predicate>
_LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS bool
wait_until(unique_lock<mutex>& __lk, const chrono::time_point<_Clock, _Duration>& __t, _Predicate __pred);
template <class _Rep, class _Period>
_LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS cv_status
wait_for(unique_lock<mutex>& __lk, const chrono::duration<_Rep, _Period>& __d);
template <class _Rep, class _Period, class _Predicate>
bool _LIBCPP_HIDE_FROM_ABI
wait_for(unique_lock<mutex>& __lk, const chrono::duration<_Rep, _Period>& __d, _Predicate __pred);
typedef __libcpp_condvar_t* native_handle_type;
_LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() { return &__cv_; }
private:
void
__do_timed_wait(unique_lock<mutex>& __lk, chrono::time_point<chrono::system_clock, chrono::nanoseconds>) _NOEXCEPT;
# if defined(_LIBCPP_HAS_COND_CLOCKWAIT)
_LIBCPP_HIDE_FROM_ABI void
__do_timed_wait(unique_lock<mutex>& __lk, chrono::time_point<chrono::steady_clock, chrono::nanoseconds>) _NOEXCEPT;
# endif
template <class _Clock>
_LIBCPP_HIDE_FROM_ABI void
__do_timed_wait(unique_lock<mutex>& __lk, chrono::time_point<_Clock, chrono::nanoseconds>) _NOEXCEPT;
};
#endif // !_LIBCPP_HAS_NO_THREADS
template <class _Rep, class _Period>
inline _LIBCPP_HIDE_FROM_ABI __enable_if_t<is_floating_point<_Rep>::value, chrono::nanoseconds>
__safe_nanosecond_cast(chrono::duration<_Rep, _Period> __d) {
using namespace chrono;
using __ratio = ratio_divide<_Period, nano>;
using __ns_rep = nanoseconds::rep;
_Rep __result_float = __d.count() * __ratio::num / __ratio::den;
_Rep __result_max = numeric_limits<__ns_rep>::max();
if (__result_float >= __result_max) {
return nanoseconds::max();
}
_Rep __result_min = numeric_limits<__ns_rep>::min();
if (__result_float <= __result_min) {
return nanoseconds::min();
}
return nanoseconds(static_cast<__ns_rep>(__result_float));
}
template <class _Rep, class _Period>
inline _LIBCPP_HIDE_FROM_ABI __enable_if_t<!is_floating_point<_Rep>::value, chrono::nanoseconds>
__safe_nanosecond_cast(chrono::duration<_Rep, _Period> __d) {
using namespace chrono;
if (__d.count() == 0) {
return nanoseconds(0);
}
using __ratio = ratio_divide<_Period, nano>;
using __ns_rep = nanoseconds::rep;
__ns_rep __result_max = numeric_limits<__ns_rep>::max();
if (__d.count() > 0 && __d.count() > __result_max / __ratio::num) {
return nanoseconds::max();
}
__ns_rep __result_min = numeric_limits<__ns_rep>::min();
if (__d.count() < 0 && __d.count() < __result_min / __ratio::num) {
return nanoseconds::min();
}
__ns_rep __result = __d.count() * __ratio::num / __ratio::den;
if (__result == 0) {
return nanoseconds(1);
}
return nanoseconds(__result);
}
#ifndef _LIBCPP_HAS_NO_THREADS
template <class _Predicate>
void condition_variable::wait(unique_lock<mutex>& __lk, _Predicate __pred) {
while (!__pred())
wait(__lk);
}
template <class _Clock, class _Duration>
cv_status condition_variable::wait_until(unique_lock<mutex>& __lk, const chrono::time_point<_Clock, _Duration>& __t) {
using namespace chrono;
using __clock_tp_ns = time_point<_Clock, nanoseconds>;
typename _Clock::time_point __now = _Clock::now();
if (__t <= __now)
return cv_status::timeout;
__clock_tp_ns __t_ns = __clock_tp_ns(std::__safe_nanosecond_cast(__t.time_since_epoch()));
__do_timed_wait(__lk, __t_ns);
return _Clock::now() < __t ? cv_status::no_timeout : cv_status::timeout;
}
template <class _Clock, class _Duration, class _Predicate>
bool condition_variable::wait_until(
unique_lock<mutex>& __lk, const chrono::time_point<_Clock, _Duration>& __t, _Predicate __pred) {
while (!__pred()) {
if (wait_until(__lk, __t) == cv_status::timeout)
return __pred();
}
return true;
}
template <class _Rep, class _Period>
cv_status condition_variable::wait_for(unique_lock<mutex>& __lk, const chrono::duration<_Rep, _Period>& __d) {
using namespace chrono;
if (__d <= __d.zero())
return cv_status::timeout;
using __ns_rep = nanoseconds::rep;
steady_clock::time_point __c_now = steady_clock::now();
# if defined(_LIBCPP_HAS_COND_CLOCKWAIT)
using __clock_tp_ns = time_point<steady_clock, nanoseconds>;
__ns_rep __now_count_ns = std::__safe_nanosecond_cast(__c_now.time_since_epoch()).count();
# else
using __clock_tp_ns = time_point<system_clock, nanoseconds>;
__ns_rep __now_count_ns = std::__safe_nanosecond_cast(system_clock::now().time_since_epoch()).count();
# endif
__ns_rep __d_ns_count = std::__safe_nanosecond_cast(__d).count();
if (__now_count_ns > numeric_limits<__ns_rep>::max() - __d_ns_count) {
__do_timed_wait(__lk, __clock_tp_ns::max());
} else {
__do_timed_wait(__lk, __clock_tp_ns(nanoseconds(__now_count_ns + __d_ns_count)));
}
return steady_clock::now() - __c_now < __d ? cv_status::no_timeout : cv_status::timeout;
}
template <class _Rep, class _Period, class _Predicate>
inline bool
condition_variable::wait_for(unique_lock<mutex>& __lk, const chrono::duration<_Rep, _Period>& __d, _Predicate __pred) {
return wait_until(__lk, chrono::steady_clock::now() + __d, std::move(__pred));
}
# if defined(_LIBCPP_HAS_COND_CLOCKWAIT)
inline void condition_variable::__do_timed_wait(
unique_lock<mutex>& __lk, chrono::time_point<chrono::steady_clock, chrono::nanoseconds> __tp) _NOEXCEPT {
using namespace chrono;
if (!__lk.owns_lock())
__throw_system_error(EPERM, "condition_variable::timed wait: mutex not locked");
nanoseconds __d = __tp.time_since_epoch();
timespec __ts;
seconds __s = duration_cast<seconds>(__d);
using __ts_sec = decltype(__ts.tv_sec);
const __ts_sec __ts_sec_max = numeric_limits<__ts_sec>::max();
if (__s.count() < __ts_sec_max) {
__ts.tv_sec = static_cast<__ts_sec>(__s.count());
__ts.tv_nsec = (__d - __s).count();
} else {
__ts.tv_sec = __ts_sec_max;
__ts.tv_nsec = giga::num - 1;
}
int __ec = pthread_cond_clockwait(&__cv_, __lk.mutex()->native_handle(), CLOCK_MONOTONIC, &__ts);
if (__ec != 0 && __ec != ETIMEDOUT)
__throw_system_error(__ec, "condition_variable timed_wait failed");
}
# endif // _LIBCPP_HAS_COND_CLOCKWAIT
template <class _Clock>
inline void condition_variable::__do_timed_wait(unique_lock<mutex>& __lk,
chrono::time_point<_Clock, chrono::nanoseconds> __tp) _NOEXCEPT {
wait_for(__lk, __tp - _Clock::now());
}
#endif // _LIBCPP_HAS_NO_THREADS
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP___CONDITION_VARIABLE_CONDITION_VARIABLE_H
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