maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/libcxx/include/__mutex_base

530 lines
16 KiB
C++
Raw Blame History

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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___MUTEX_BASE
#define _LIBCPP___MUTEX_BASE
#include <__chrono/duration.h>
#include <__chrono/steady_clock.h>
#include <__chrono/system_clock.h>
#include <__chrono/time_point.h>
#include <__config>
#include <__threading_support>
#include <ratio>
#include <system_error>
#include <time.h>
#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
class _LIBCPP_TYPE_VIS _LIBCPP_THREAD_SAFETY_ANNOTATION(capability("mutex")) mutex
{
__libcpp_mutex_t __m_ = _LIBCPP_MUTEX_INITIALIZER;
public:
_LIBCPP_INLINE_VISIBILITY
_LIBCPP_CONSTEXPR mutex() = default;
mutex(const mutex&) = delete;
mutex& operator=(const mutex&) = delete;
#if defined(_LIBCPP_HAS_TRIVIAL_MUTEX_DESTRUCTION)
~mutex() = default;
#else
~mutex() _NOEXCEPT;
#endif
void lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability());
bool try_lock() _NOEXCEPT _LIBCPP_THREAD_SAFETY_ANNOTATION(try_acquire_capability(true));
void unlock() _NOEXCEPT _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability());
typedef __libcpp_mutex_t* native_handle_type;
_LIBCPP_INLINE_VISIBILITY native_handle_type native_handle() {return &__m_;}
};
static_assert(is_nothrow_default_constructible<mutex>::value,
"the default constructor for std::mutex must be nothrow");
struct _LIBCPP_TYPE_VIS defer_lock_t { explicit defer_lock_t() = default; };
struct _LIBCPP_TYPE_VIS try_to_lock_t { explicit try_to_lock_t() = default; };
struct _LIBCPP_TYPE_VIS adopt_lock_t { explicit adopt_lock_t() = default; };
#if defined(_LIBCPP_CXX03_LANG) || defined(_LIBCPP_BUILDING_LIBRARY)
extern _LIBCPP_EXPORTED_FROM_ABI const defer_lock_t defer_lock;
extern _LIBCPP_EXPORTED_FROM_ABI const try_to_lock_t try_to_lock;
extern _LIBCPP_EXPORTED_FROM_ABI const adopt_lock_t adopt_lock;
#else
/* inline */ constexpr defer_lock_t defer_lock = defer_lock_t();
/* inline */ constexpr try_to_lock_t try_to_lock = try_to_lock_t();
/* inline */ constexpr adopt_lock_t adopt_lock = adopt_lock_t();
#endif
template <class _Mutex>
class _LIBCPP_TEMPLATE_VIS _LIBCPP_THREAD_SAFETY_ANNOTATION(scoped_lockable)
lock_guard
{
public:
typedef _Mutex mutex_type;
private:
mutex_type& __m_;
public:
_LIBCPP_NODISCARD_EXT _LIBCPP_INLINE_VISIBILITY
explicit lock_guard(mutex_type& __m) _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability(__m))
: __m_(__m) {__m_.lock();}
_LIBCPP_NODISCARD_EXT _LIBCPP_INLINE_VISIBILITY
lock_guard(mutex_type& __m, adopt_lock_t) _LIBCPP_THREAD_SAFETY_ANNOTATION(requires_capability(__m))
: __m_(__m) {}
_LIBCPP_INLINE_VISIBILITY
~lock_guard() _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability()) {__m_.unlock();}
private:
lock_guard(lock_guard const&) = delete;
lock_guard& operator=(lock_guard const&) = delete;
};
template <class _Mutex>
class _LIBCPP_TEMPLATE_VIS unique_lock
{
public:
typedef _Mutex mutex_type;
private:
mutex_type* __m_;
bool __owns_;
public:
_LIBCPP_INLINE_VISIBILITY
unique_lock() _NOEXCEPT : __m_(nullptr), __owns_(false) {}
_LIBCPP_INLINE_VISIBILITY
explicit unique_lock(mutex_type& __m)
: __m_(_VSTD::addressof(__m)), __owns_(true) {__m_->lock();}
_LIBCPP_INLINE_VISIBILITY
unique_lock(mutex_type& __m, defer_lock_t) _NOEXCEPT
: __m_(_VSTD::addressof(__m)), __owns_(false) {}
_LIBCPP_INLINE_VISIBILITY
unique_lock(mutex_type& __m, try_to_lock_t)
: __m_(_VSTD::addressof(__m)), __owns_(__m.try_lock()) {}
_LIBCPP_INLINE_VISIBILITY
unique_lock(mutex_type& __m, adopt_lock_t)
: __m_(_VSTD::addressof(__m)), __owns_(true) {}
template <class _Clock, class _Duration>
_LIBCPP_INLINE_VISIBILITY
unique_lock(mutex_type& __m, const chrono::time_point<_Clock, _Duration>& __t)
: __m_(_VSTD::addressof(__m)), __owns_(__m.try_lock_until(__t)) {}
template <class _Rep, class _Period>
_LIBCPP_INLINE_VISIBILITY
unique_lock(mutex_type& __m, const chrono::duration<_Rep, _Period>& __d)
: __m_(_VSTD::addressof(__m)), __owns_(__m.try_lock_for(__d)) {}
_LIBCPP_INLINE_VISIBILITY
~unique_lock()
{
if (__owns_)
__m_->unlock();
}
unique_lock(unique_lock const&) = delete;
unique_lock& operator=(unique_lock const&) = delete;
_LIBCPP_INLINE_VISIBILITY
unique_lock(unique_lock&& __u) _NOEXCEPT
: __m_(__u.__m_), __owns_(__u.__owns_)
{__u.__m_ = nullptr; __u.__owns_ = false;}
_LIBCPP_INLINE_VISIBILITY
unique_lock& operator=(unique_lock&& __u) _NOEXCEPT
{
if (__owns_)
__m_->unlock();
__m_ = __u.__m_;
__owns_ = __u.__owns_;
__u.__m_ = nullptr;
__u.__owns_ = false;
return *this;
}
void lock();
bool try_lock();
template <class _Rep, class _Period>
bool try_lock_for(const chrono::duration<_Rep, _Period>& __d);
template <class _Clock, class _Duration>
bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t);
void unlock();
_LIBCPP_INLINE_VISIBILITY
void swap(unique_lock& __u) _NOEXCEPT
{
_VSTD::swap(__m_, __u.__m_);
_VSTD::swap(__owns_, __u.__owns_);
}
_LIBCPP_INLINE_VISIBILITY
mutex_type* release() _NOEXCEPT
{
mutex_type* __m = __m_;
__m_ = nullptr;
__owns_ = false;
return __m;
}
_LIBCPP_INLINE_VISIBILITY
bool owns_lock() const _NOEXCEPT {return __owns_;}
_LIBCPP_INLINE_VISIBILITY
explicit operator bool() const _NOEXCEPT {return __owns_;}
_LIBCPP_INLINE_VISIBILITY
mutex_type* mutex() const _NOEXCEPT {return __m_;}
};
template <class _Mutex>
void
unique_lock<_Mutex>::lock()
{
if (__m_ == nullptr)
__throw_system_error(EPERM, "unique_lock::lock: references null mutex");
if (__owns_)
__throw_system_error(EDEADLK, "unique_lock::lock: already locked");
__m_->lock();
__owns_ = true;
}
template <class _Mutex>
bool
unique_lock<_Mutex>::try_lock()
{
if (__m_ == nullptr)
__throw_system_error(EPERM, "unique_lock::try_lock: references null mutex");
if (__owns_)
__throw_system_error(EDEADLK, "unique_lock::try_lock: already locked");
__owns_ = __m_->try_lock();
return __owns_;
}
template <class _Mutex>
template <class _Rep, class _Period>
bool
unique_lock<_Mutex>::try_lock_for(const chrono::duration<_Rep, _Period>& __d)
{
if (__m_ == nullptr)
__throw_system_error(EPERM, "unique_lock::try_lock_for: references null mutex");
if (__owns_)
__throw_system_error(EDEADLK, "unique_lock::try_lock_for: already locked");
__owns_ = __m_->try_lock_for(__d);
return __owns_;
}
template <class _Mutex>
template <class _Clock, class _Duration>
bool
unique_lock<_Mutex>::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t)
{
if (__m_ == nullptr)
__throw_system_error(EPERM, "unique_lock::try_lock_until: references null mutex");
if (__owns_)
__throw_system_error(EDEADLK, "unique_lock::try_lock_until: already locked");
__owns_ = __m_->try_lock_until(__t);
return __owns_;
}
template <class _Mutex>
void
unique_lock<_Mutex>::unlock()
{
if (!__owns_)
__throw_system_error(EPERM, "unique_lock::unlock: not locked");
__m_->unlock();
__owns_ = false;
}
template <class _Mutex>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(unique_lock<_Mutex>& __x, unique_lock<_Mutex>& __y) _NOEXCEPT
{__x.swap(__y);}
//enum class cv_status
_LIBCPP_DECLARE_STRONG_ENUM(cv_status)
{
no_timeout,
timeout
};
_LIBCPP_DECLARE_STRONG_ENUM_EPILOG(cv_status)
class _LIBCPP_TYPE_VIS condition_variable
{
__libcpp_condvar_t __cv_ = _LIBCPP_CONDVAR_INITIALIZER;
public:
_LIBCPP_INLINE_VISIBILITY
_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_INLINE_VISIBILITY
wait_for(unique_lock<mutex>& __lk,
const chrono::duration<_Rep, _Period>& __d,
_Predicate __pred);
typedef __libcpp_condvar_t* native_handle_type;
_LIBCPP_INLINE_VISIBILITY 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)
void __do_timed_wait(unique_lock<mutex>& __lk,
chrono::time_point<chrono::steady_clock, chrono::nanoseconds>) _NOEXCEPT;
#endif
template <class _Clock>
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_INLINE_VISIBILITY
typename enable_if
<
is_floating_point<_Rep>::value,
chrono::nanoseconds
>::type
__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_INLINE_VISIBILITY
typename enable_if
<
!is_floating_point<_Rep>::value,
chrono::nanoseconds
>::type
__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(_VSTD::__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 = _VSTD::__safe_nanosecond_cast(__c_now.time_since_epoch()).count();
#else
using __clock_tp_ns = time_point<system_clock, nanoseconds>;
__ns_rep __now_count_ns = _VSTD::__safe_nanosecond_cast(system_clock::now().time_since_epoch()).count();
#endif
__ns_rep __d_ns_count = _VSTD::__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,
_VSTD::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___MUTEX_BASE
Reference in New Issue View Git Blame Copy Permalink