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// condition_variable -*- C++ -*-
// Copyright (C) 2008-2022 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/>.
#include <condition_variable>
#include <cstdlib>
#ifdef _GLIBCXX_HAS_GTHREADS
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
condition_variable::condition_variable() noexcept = default;
condition_variable::~condition_variable() noexcept = default;
void
condition_variable::wait(unique_lock<mutex>& __lock)
{
_M_cond.wait(*__lock.mutex());
}
void
condition_variable::notify_one() noexcept
{
_M_cond.notify_one();
}
void
condition_variable::notify_all() noexcept
{
_M_cond.notify_all();
}
extern void
__at_thread_exit(__at_thread_exit_elt*);
namespace
{
__gthread_key_t key;
void run(void* p)
{
auto elt = (__at_thread_exit_elt*)p;
while (elt)
{
auto next = elt->_M_next;
elt->_M_cb(elt);
elt = next;
}
}
void run()
{
auto elt = (__at_thread_exit_elt*)__gthread_getspecific(key);
__gthread_setspecific(key, nullptr);
run(elt);
}
struct notifier final : __at_thread_exit_elt
{
notifier(condition_variable& cv, unique_lock<mutex>& l)
: cv(&cv), mx(l.release())
{
_M_cb = &notifier::run;
__at_thread_exit(this);
}
~notifier()
{
mx->unlock();
cv->notify_all();
}
condition_variable* cv;
mutex* mx;
static void run(void* p) { delete static_cast<notifier*>(p); }
};
void key_init() {
struct key_s {
key_s() { __gthread_key_create (&key, run); }
~key_s() { __gthread_key_delete (key); }
};
static key_s ks;
// Also make sure the callbacks are run by std::exit.
std::atexit (run);
}
}
void
__at_thread_exit(__at_thread_exit_elt* elt)
{
static __gthread_once_t once = __GTHREAD_ONCE_INIT;
__gthread_once (&once, key_init);
elt->_M_next = (__at_thread_exit_elt*)__gthread_getspecific(key);
__gthread_setspecific(key, elt);
}
void
notify_all_at_thread_exit(condition_variable& cv, unique_lock<mutex> l)
{
(void) new notifier{cv, l};
}
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif // _GLIBCXX_HAS_GTHREADS