notify.hxx

/*
 * Copyright (C) 2003-2014 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef MPD_NOTIFY_HXX
#define MPD_NOTIFY_HXX

#include "thread/Mutex.hxx"
#include "thread/Cond.hxx"

struct notify {
	Mutex mutex;
	Cond cond;
	bool pending;

#if !defined(WIN32) && !defined(__BIONIC__)
	constexpr
#endif
	notify():pending(false) {}

	/**
	 * Wait for a notification.  Return immediately if we have already
	 * been notified since we last returned from notify_wait().
	 */
	void Wait();

	/**
	 * Notify the thread.  This function never blocks.
	 */
	void Signal();

	/**
	 * Clears a pending notification.
	 */
	void Clear();
};

#endif