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//  -*- 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

// .

/** @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 

#else

#include 

#include  // 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& __lock);

    template

      void

      wait(unique_lock& __lock, _Predicate __p)

      {

	while (!__p())

	  wait(__lock);

      }

    template

      cv_status

      wait_until(unique_lock& __lock,

		 const chrono::time_point<__clock_t, _Duration>& __atime)

      { return __wait_until_impl(__lock, __atime); }

    template

      cv_status

      wait_until(unique_lock& __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

      bool

      wait_until(unique_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

      cv_status

      wait_for(unique_lock& __lock,

	       const chrono::duration<_Rep, _Period>& __rtime)

      { return wait_until(__lock, __clock_t::now() + __rtime); }

    template

      bool

      wait_for(unique_lock& __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

      cv_status

      __wait_until_impl(unique_lock& __lock,

			const chrono::time_point<__clock_t, _Dur>& __atime)

      {

	auto __s = chrono::time_point_cast(__atime);

	auto __ns = chrono::duration_cast(__atime - __s);

	__gthread_time_t __ts =

	  {

	    static_cast(__s.time_since_epoch().count()),

	    static_cast(__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

      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 __lock(_M_mutex);

      _M_cond.notify_one();

    }

    void

    notify_all() noexcept

    {

      lock_guard __lock(_M_mutex);

      _M_cond.notify_all();

    }

    template

      void

      wait(_Lock& __lock)

      {

	unique_lock __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 __my_lock2(std::move(__my_lock));

	_M_cond.wait(__my_lock2);

      }

    template

      void

      wait(_Lock& __lock, _Predicate __p)

      {

	while (!__p())

	  wait(__lock);

      }

    template

      cv_status

      wait_until(_Lock& __lock,

		 const chrono::time_point<_Clock, _Duration>& __atime)

      {

	unique_lock __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 __my_lock2(std::move(__my_lock));

	return _M_cond.wait_until(__my_lock2, __atime);

      }

    template

	     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

      cv_status

      wait_for(_Lock& __lock, const chrono::duration<_Rep, _Period>& __rtime)

      { return wait_until(__lock, __clock_t::now() + __rtime); }

    template

	     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