287 lines
7.8 KiB
C++
287 lines
7.8 KiB
C++
// <condition_variable> -*- C++ -*-
|
|
|
|
// Copyright (C) 2008-2013 Free Software Foundation, Inc.
|
|
//
|
|
// This file is part of the GNU ISO C++ Library. This library is free
|
|
// software; you can redistribute it and/or modify it under the
|
|
// terms of the GNU General Public License as published by the
|
|
// Free Software Foundation; either version 3, or (at your option)
|
|
// any later version.
|
|
|
|
// This library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
|
|
// Under Section 7 of GPL version 3, you are granted additional
|
|
// permissions described in the GCC Runtime Library Exception, version
|
|
// 3.1, as published by the Free Software Foundation.
|
|
|
|
// You should have received a copy of the GNU General Public License and
|
|
// a copy of the GCC Runtime Library Exception along with this program;
|
|
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
|
// <http://www.gnu.org/licenses/>.
|
|
|
|
/** @file include/condition_variable
|
|
* This is a Standard C++ Library header.
|
|
*/
|
|
|
|
#ifndef _GLIBCXX_CONDITION_VARIABLE
|
|
#define _GLIBCXX_CONDITION_VARIABLE 1
|
|
|
|
#pragma GCC system_header
|
|
|
|
#if __cplusplus < 201103L
|
|
# include <bits/c++0x_warning.h>
|
|
#else
|
|
|
|
#include <chrono>
|
|
#include <mutex> // unique_lock
|
|
|
|
#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
|
|
|
|
namespace std _GLIBCXX_VISIBILITY(default)
|
|
{
|
|
_GLIBCXX_BEGIN_NAMESPACE_VERSION
|
|
|
|
/**
|
|
* @defgroup condition_variables Condition Variables
|
|
* @ingroup concurrency
|
|
*
|
|
* Classes for condition_variable support.
|
|
* @{
|
|
*/
|
|
|
|
/// cv_status
|
|
enum class cv_status { no_timeout, timeout };
|
|
|
|
/// condition_variable
|
|
class condition_variable
|
|
{
|
|
typedef chrono::system_clock __clock_t;
|
|
typedef __gthread_cond_t __native_type;
|
|
|
|
#ifdef __GTHREAD_COND_INIT
|
|
__native_type _M_cond = __GTHREAD_COND_INIT;
|
|
#else
|
|
__native_type _M_cond;
|
|
#endif
|
|
|
|
public:
|
|
typedef __native_type* native_handle_type;
|
|
|
|
condition_variable() noexcept;
|
|
~condition_variable() noexcept;
|
|
|
|
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>& __lock);
|
|
|
|
template<typename _Predicate>
|
|
void
|
|
wait(unique_lock<mutex>& __lock, _Predicate __p)
|
|
{
|
|
while (!__p())
|
|
wait(__lock);
|
|
}
|
|
|
|
template<typename _Duration>
|
|
cv_status
|
|
wait_until(unique_lock<mutex>& __lock,
|
|
const chrono::time_point<__clock_t, _Duration>& __atime)
|
|
{ return __wait_until_impl(__lock, __atime); }
|
|
|
|
template<typename _Clock, typename _Duration>
|
|
cv_status
|
|
wait_until(unique_lock<mutex>& __lock,
|
|
const chrono::time_point<_Clock, _Duration>& __atime)
|
|
{
|
|
// DR 887 - Sync unknown clock to known clock.
|
|
const typename _Clock::time_point __c_entry = _Clock::now();
|
|
const __clock_t::time_point __s_entry = __clock_t::now();
|
|
const auto __delta = __atime - __c_entry;
|
|
const auto __s_atime = __s_entry + __delta;
|
|
|
|
return __wait_until_impl(__lock, __s_atime);
|
|
}
|
|
|
|
template<typename _Clock, typename _Duration, typename _Predicate>
|
|
bool
|
|
wait_until(unique_lock<mutex>& __lock,
|
|
const chrono::time_point<_Clock, _Duration>& __atime,
|
|
_Predicate __p)
|
|
{
|
|
while (!__p())
|
|
if (wait_until(__lock, __atime) == cv_status::timeout)
|
|
return __p();
|
|
return true;
|
|
}
|
|
|
|
template<typename _Rep, typename _Period>
|
|
cv_status
|
|
wait_for(unique_lock<mutex>& __lock,
|
|
const chrono::duration<_Rep, _Period>& __rtime)
|
|
{ return wait_until(__lock, __clock_t::now() + __rtime); }
|
|
|
|
template<typename _Rep, typename _Period, typename _Predicate>
|
|
bool
|
|
wait_for(unique_lock<mutex>& __lock,
|
|
const chrono::duration<_Rep, _Period>& __rtime,
|
|
_Predicate __p)
|
|
{ return wait_until(__lock, __clock_t::now() + __rtime, std::move(__p)); }
|
|
|
|
native_handle_type
|
|
native_handle()
|
|
{ return &_M_cond; }
|
|
|
|
private:
|
|
template<typename _Dur>
|
|
cv_status
|
|
__wait_until_impl(unique_lock<mutex>& __lock,
|
|
const chrono::time_point<__clock_t, _Dur>& __atime)
|
|
{
|
|
auto __s = chrono::time_point_cast<chrono::seconds>(__atime);
|
|
auto __ns = chrono::duration_cast<chrono::nanoseconds>(__atime - __s);
|
|
|
|
__gthread_time_t __ts =
|
|
{
|
|
static_cast<std::time_t>(__s.time_since_epoch().count()),
|
|
static_cast<long>(__ns.count())
|
|
};
|
|
|
|
__gthread_cond_timedwait(&_M_cond, __lock.mutex()->native_handle(),
|
|
&__ts);
|
|
|
|
return (__clock_t::now() < __atime
|
|
? cv_status::no_timeout : cv_status::timeout);
|
|
}
|
|
};
|
|
|
|
/// condition_variable_any
|
|
// Like above, but mutex is not required to have try_lock.
|
|
class condition_variable_any
|
|
{
|
|
typedef chrono::system_clock __clock_t;
|
|
condition_variable _M_cond;
|
|
mutex _M_mutex;
|
|
|
|
// scoped unlock - unlocks in ctor, re-locks in dtor
|
|
template<typename _Lock>
|
|
struct _Unlock
|
|
{
|
|
explicit _Unlock(_Lock& __lk) : _M_lock(__lk) { __lk.unlock(); }
|
|
|
|
~_Unlock() noexcept(false)
|
|
{
|
|
if (uncaught_exception())
|
|
__try { _M_lock.lock(); } __catch(...) { }
|
|
else
|
|
_M_lock.lock();
|
|
}
|
|
|
|
_Unlock(const _Unlock&) = delete;
|
|
_Unlock& operator=(const _Unlock&) = delete;
|
|
|
|
_Lock& _M_lock;
|
|
};
|
|
|
|
public:
|
|
|
|
condition_variable_any() noexcept;
|
|
~condition_variable_any() noexcept;
|
|
|
|
condition_variable_any(const condition_variable_any&) = delete;
|
|
condition_variable_any& operator=(const condition_variable_any&) = delete;
|
|
|
|
void
|
|
notify_one() noexcept
|
|
{
|
|
lock_guard<mutex> __lock(_M_mutex);
|
|
_M_cond.notify_one();
|
|
}
|
|
|
|
void
|
|
notify_all() noexcept
|
|
{
|
|
lock_guard<mutex> __lock(_M_mutex);
|
|
_M_cond.notify_all();
|
|
}
|
|
|
|
template<typename _Lock>
|
|
void
|
|
wait(_Lock& __lock)
|
|
{
|
|
unique_lock<mutex> __my_lock(_M_mutex);
|
|
_Unlock<_Lock> __unlock(__lock);
|
|
// _M_mutex must be unlocked before re-locking __lock so move
|
|
// ownership of _M_mutex lock to an object with shorter lifetime.
|
|
unique_lock<mutex> __my_lock2(std::move(__my_lock));
|
|
_M_cond.wait(__my_lock2);
|
|
}
|
|
|
|
|
|
template<typename _Lock, typename _Predicate>
|
|
void
|
|
wait(_Lock& __lock, _Predicate __p)
|
|
{
|
|
while (!__p())
|
|
wait(__lock);
|
|
}
|
|
|
|
template<typename _Lock, typename _Clock, typename _Duration>
|
|
cv_status
|
|
wait_until(_Lock& __lock,
|
|
const chrono::time_point<_Clock, _Duration>& __atime)
|
|
{
|
|
unique_lock<mutex> __my_lock(_M_mutex);
|
|
_Unlock<_Lock> __unlock(__lock);
|
|
// _M_mutex must be unlocked before re-locking __lock so move
|
|
// ownership of _M_mutex lock to an object with shorter lifetime.
|
|
unique_lock<mutex> __my_lock2(std::move(__my_lock));
|
|
return _M_cond.wait_until(__my_lock2, __atime);
|
|
}
|
|
|
|
template<typename _Lock, typename _Clock,
|
|
typename _Duration, typename _Predicate>
|
|
bool
|
|
wait_until(_Lock& __lock,
|
|
const chrono::time_point<_Clock, _Duration>& __atime,
|
|
_Predicate __p)
|
|
{
|
|
while (!__p())
|
|
if (wait_until(__lock, __atime) == cv_status::timeout)
|
|
return __p();
|
|
return true;
|
|
}
|
|
|
|
template<typename _Lock, typename _Rep, typename _Period>
|
|
cv_status
|
|
wait_for(_Lock& __lock, const chrono::duration<_Rep, _Period>& __rtime)
|
|
{ return wait_until(__lock, __clock_t::now() + __rtime); }
|
|
|
|
template<typename _Lock, typename _Rep,
|
|
typename _Period, typename _Predicate>
|
|
bool
|
|
wait_for(_Lock& __lock,
|
|
const chrono::duration<_Rep, _Period>& __rtime, _Predicate __p)
|
|
{ return wait_until(__lock, __clock_t::now() + __rtime, std::move(__p)); }
|
|
};
|
|
|
|
// @} group condition_variables
|
|
_GLIBCXX_END_NAMESPACE_VERSION
|
|
} // namespace
|
|
|
|
#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
|
|
|
|
#endif // C++11
|
|
|
|
#endif // _GLIBCXX_CONDITION_VARIABLE
|