// <condition_variable> -*- C++ -*-
-// Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
+// Copyright (C) 2008-2020 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
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
-/** @file condition_variable
+/** @file include/condition_variable
* This is a Standard C++ Library header.
*/
#pragma GCC system_header
-#ifndef __GXX_EXPERIMENTAL_CXX0X__
+#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)
+#include <bits/std_mutex.h>
+#include <bits/unique_lock.h>
+#include <ext/concurrence.h>
+#include <bits/alloc_traits.h>
+#include <bits/allocator.h>
+#include <bits/unique_ptr.h>
+#include <bits/shared_ptr.h>
+#include <bits/cxxabi_forced.h>
-_GLIBCXX_BEGIN_NAMESPACE(std)
+#if __cplusplus > 201703L
+# include <stop_token>
+#endif
+
+#if defined(_GLIBCXX_HAS_GTHREADS)
+
+namespace std _GLIBCXX_VISIBILITY(default)
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @defgroup condition_variables Condition Variables
/// cv_status
enum class cv_status { no_timeout, timeout };
-
+
/// condition_variable
class condition_variable
{
- typedef chrono::system_clock __clock_t;
+ using steady_clock = chrono::steady_clock;
+ using system_clock = chrono::system_clock;
+#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
+ using __clock_t = steady_clock;
+#else
+ using __clock_t = system_clock;
+#endif
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() throw ();
- ~condition_variable() throw ();
+ condition_variable() noexcept;
+ ~condition_variable() noexcept;
condition_variable(const condition_variable&) = delete;
condition_variable& operator=(const condition_variable&) = delete;
void
- notify_one();
+ notify_one() noexcept;
void
- notify_all();
+ notify_all() noexcept;
void
- wait(unique_lock<mutex>& __lock);
+ wait(unique_lock<mutex>& __lock) noexcept;
template<typename _Predicate>
void
wait(__lock);
}
+#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
+ template<typename _Duration>
+ cv_status
+ wait_until(unique_lock<mutex>& __lock,
+ const chrono::time_point<steady_clock, _Duration>& __atime)
+ { return __wait_until_impl(__lock, __atime); }
+#endif
+
template<typename _Duration>
cv_status
wait_until(unique_lock<mutex>& __lock,
- const chrono::time_point<__clock_t, _Duration>& __atime)
+ const chrono::time_point<system_clock, _Duration>& __atime)
{ return __wait_until_impl(__lock, __atime); }
template<typename _Clock, typename _Duration>
wait_until(unique_lock<mutex>& __lock,
const chrono::time_point<_Clock, _Duration>& __atime)
{
- // DR 887 - Sync unknown clock to known clock.
+#if __cplusplus > 201703L
+ static_assert(chrono::is_clock_v<_Clock>);
+#endif
const typename _Clock::time_point __c_entry = _Clock::now();
const __clock_t::time_point __s_entry = __clock_t::now();
- const chrono::nanoseconds __delta = __atime - __c_entry;
- const __clock_t::time_point __s_atime = __s_entry + __delta;
-
- return __wait_until_impl(__lock, __s_atime);
+ const auto __delta = __atime - __c_entry;
+ const auto __s_atime = __s_entry + __delta;
+
+ if (__wait_until_impl(__lock, __s_atime) == cv_status::no_timeout)
+ return cv_status::no_timeout;
+ // We got a timeout when measured against __clock_t but
+ // we need to check against the caller-supplied clock
+ // to tell whether we should return a timeout.
+ if (_Clock::now() < __atime)
+ return cv_status::no_timeout;
+ return cv_status::timeout;
}
template<typename _Clock, typename _Duration, typename _Predicate>
cv_status
wait_for(unique_lock<mutex>& __lock,
const chrono::duration<_Rep, _Period>& __rtime)
- { return wait_until(__lock, __clock_t::now() + __rtime); }
+ {
+ using __dur = typename steady_clock::duration;
+ auto __reltime = chrono::duration_cast<__dur>(__rtime);
+ if (__reltime < __rtime)
+ ++__reltime;
+ return wait_until(__lock, steady_clock::now() + __reltime);
+ }
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)); }
+ {
+ using __dur = typename steady_clock::duration;
+ auto __reltime = chrono::duration_cast<__dur>(__rtime);
+ if (__reltime < __rtime)
+ ++__reltime;
+ return wait_until(__lock, steady_clock::now() + __reltime,
+ std::move(__p));
+ }
native_handle_type
native_handle()
{ return &_M_cond; }
private:
- template<typename _Clock, typename _Duration>
+#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
+ template<typename _Dur>
cv_status
__wait_until_impl(unique_lock<mutex>& __lock,
- const chrono::time_point<_Clock, _Duration>& __atime)
+ const chrono::time_point<steady_clock, _Dur>& __atime)
{
- chrono::time_point<__clock_t, chrono::seconds> __s =
- chrono::time_point_cast<chrono::seconds>(__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())
+ };
+
+ pthread_cond_clockwait(&_M_cond, __lock.mutex()->native_handle(),
+ CLOCK_MONOTONIC,
+ &__ts);
+
+ return (steady_clock::now() < __atime
+ ? cv_status::no_timeout : cv_status::timeout);
+ }
+#endif
- chrono::nanoseconds __ns =
- chrono::duration_cast<chrono::nanoseconds>(__atime - __s);
+ template<typename _Dur>
+ cv_status
+ __wait_until_impl(unique_lock<mutex>& __lock,
+ const chrono::time_point<system_clock, _Dur>& __atime)
+ {
+ auto __s = chrono::time_point_cast<chrono::seconds>(__atime);
+ auto __ns = chrono::duration_cast<chrono::nanoseconds>(__atime - __s);
__gthread_time_t __ts =
{
__gthread_cond_timedwait(&_M_cond, __lock.mutex()->native_handle(),
&__ts);
- return (_Clock::now() < __atime
+ return (system_clock::now() < __atime
? cv_status::no_timeout : cv_status::timeout);
}
};
+ void
+ notify_all_at_thread_exit(condition_variable&, unique_lock<mutex>);
+
+ struct __at_thread_exit_elt
+ {
+ __at_thread_exit_elt* _M_next;
+ void (*_M_cb)(void*);
+ };
+
+ inline namespace _V2 {
+
/// condition_variable_any
// Like above, but mutex is not required to have try_lock.
class condition_variable_any
{
- typedef chrono::system_clock __clock_t;
+#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
+ using __clock_t = chrono::steady_clock;
+#else
+ using __clock_t = chrono::system_clock;
+#endif
condition_variable _M_cond;
- mutex _M_mutex;
+ shared_ptr<mutex> _M_mutex;
- public:
- typedef condition_variable::native_handle_type native_handle_type;
+ // scoped unlock - unlocks in ctor, re-locks in dtor
+ template<typename _Lock>
+ struct _Unlock
+ {
+ explicit _Unlock(_Lock& __lk) : _M_lock(__lk) { __lk.unlock(); }
+
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+ ~_Unlock() noexcept(false)
+ {
+ if (uncaught_exception())
+ {
+ __try
+ { _M_lock.lock(); }
+ __catch(const __cxxabiv1::__forced_unwind&)
+ { __throw_exception_again; }
+ __catch(...)
+ { }
+ }
+ else
+ _M_lock.lock();
+ }
+#pragma GCC diagnostic pop
+
+ _Unlock(const _Unlock&) = delete;
+ _Unlock& operator=(const _Unlock&) = delete;
+
+ _Lock& _M_lock;
+ };
- condition_variable_any() throw ();
- ~condition_variable_any() throw ();
+ public:
+ condition_variable_any() : _M_mutex(std::make_shared<mutex>()) { }
+ ~condition_variable_any() = default;
condition_variable_any(const condition_variable_any&) = delete;
condition_variable_any& operator=(const condition_variable_any&) = delete;
void
- notify_one()
+ notify_one() noexcept
{
- lock_guard<mutex> __lock(_M_mutex);
+ lock_guard<mutex> __lock(*_M_mutex);
_M_cond.notify_one();
}
void
- notify_all()
+ notify_all() noexcept
{
- lock_guard<mutex> __lock(_M_mutex);
+ lock_guard<mutex> __lock(*_M_mutex);
_M_cond.notify_all();
}
void
wait(_Lock& __lock)
{
- unique_lock<mutex> __my_lock(_M_mutex);
- __lock.unlock();
- _M_cond.wait(__my_lock);
- __lock.lock();
+ shared_ptr<mutex> __mutex = _M_mutex;
+ unique_lock<mutex> __my_lock(*__mutex);
+ _Unlock<_Lock> __unlock(__lock);
+ // *__mutex must be unlocked before re-locking __lock so move
+ // ownership of *__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_until(_Lock& __lock,
const chrono::time_point<_Clock, _Duration>& __atime)
{
- unique_lock<mutex> __my_lock(_M_mutex);
- __lock.unlock();
- cv_status __status = _M_cond.wait_until(__my_lock, __atime);
- __lock.lock();
- return __status;
+ shared_ptr<mutex> __mutex = _M_mutex;
+ unique_lock<mutex> __my_lock(*__mutex);
+ _Unlock<_Lock> __unlock(__lock);
+ // *__mutex must be unlocked before re-locking __lock so move
+ // ownership of *__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,
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.native_handle(); }
- };
+#ifdef __cpp_lib_jthread
+ template <class _Lock, class _Predicate>
+ bool wait(_Lock& __lock,
+ stop_token __stoken,
+ _Predicate __p)
+ {
+ if (__stoken.stop_requested())
+ {
+ return __p();
+ }
+
+ std::stop_callback __cb(__stoken, [this] { notify_all(); });
+ shared_ptr<mutex> __mutex = _M_mutex;
+ while (!__p())
+ {
+ unique_lock<mutex> __my_lock(*__mutex);
+ if (__stoken.stop_requested())
+ {
+ return false;
+ }
+ // *__mutex must be unlocked before re-locking __lock so move
+ // ownership of *__mutex lock to an object with shorter lifetime.
+ _Unlock<_Lock> __unlock(__lock);
+ unique_lock<mutex> __my_lock2(std::move(__my_lock));
+ _M_cond.wait(__my_lock2);
+ }
+ return true;
+ }
- // @} group condition_variables
-_GLIBCXX_END_NAMESPACE
+ template <class _Lock, class _Clock, class _Duration, class _Predicate>
+ bool wait_until(_Lock& __lock,
+ stop_token __stoken,
+ const chrono::time_point<_Clock, _Duration>& __abs_time,
+ _Predicate __p)
+ {
+ if (__stoken.stop_requested())
+ {
+ return __p();
+ }
+
+ std::stop_callback __cb(__stoken, [this] { notify_all(); });
+ shared_ptr<mutex> __mutex = _M_mutex;
+ while (!__p())
+ {
+ bool __stop;
+ {
+ unique_lock<mutex> __my_lock(*__mutex);
+ if (__stoken.stop_requested())
+ {
+ return false;
+ }
+ _Unlock<_Lock> __u(__lock);
+ unique_lock<mutex> __my_lock2(std::move(__my_lock));
+ const auto __status = _M_cond.wait_until(__my_lock2, __abs_time);
+ __stop = (__status == std::cv_status::timeout) || __stoken.stop_requested();
+ }
+ if (__stop)
+ {
+ return __p();
+ }
+ }
+ return true;
+ }
-#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
+ template <class _Lock, class _Rep, class _Period, class _Predicate>
+ bool wait_for(_Lock& __lock,
+ stop_token __stoken,
+ const chrono::duration<_Rep, _Period>& __rel_time,
+ _Predicate __p)
+ {
+ auto __abst = std::chrono::steady_clock::now() + __rel_time;
+ return wait_until(__lock,
+ std::move(__stoken),
+ __abst,
+ std::move(__p));
+ }
+#endif
+ };
+
+ } // end inline namespace
-#endif // __GXX_EXPERIMENTAL_CXX0X__
+ // @} group condition_variables
+_GLIBCXX_END_NAMESPACE_VERSION
+} // namespace
+#endif // _GLIBCXX_HAS_GTHREADS
+#endif // C++11
#endif // _GLIBCXX_CONDITION_VARIABLE
git://gcc.gnu.org / gcc.git / blobdiff