haiku/src/servers/registrar/EventQueue.h

//------------------------------------------------------------------------------
//	Copyright (c) 2001-2002, OpenBeOS
//
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//	copy of this software and associated documentation files (the "Software"),
//	to deal in the Software without restriction, including without limitation
//	the rights to use, copy, modify, merge, publish, distribute, sublicense,
//	and/or sell copies of the Software, and to permit persons to whom the
//	Software is furnished to do so, subject to the following conditions:
//
//	The above copyright notice and this permission notice shall be included in
//	all copies or substantial portions of the Software.
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//	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
//	FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
//	DEALINGS IN THE SOFTWARE.
//
//	File Name:		EventQueue.h
//	Author:			Ingo Weinhold (bonefish@users.sf.net)
//					YellowBites (http://www.yellowbites.com)
//	Description:	A class providing a mechanism for executing events at
//					specified times.
//------------------------------------------------------------------------------

#ifndef EVENT_QUEUE_H
#define EVENT_QUEUE_H

#include <List.h>
#include <Locker.h>
#include <OS.h>

class Event;

class EventQueue : public BLocker {
public:
	EventQueue(const char *name = NULL);
	virtual ~EventQueue();

	status_t InitCheck();

	void Die();

	bool AddEvent(Event *event);
	bool RemoveEvent(Event *event);
	void ModifyEvent(Event *event, bigtime_t newTime);

 private:
	bool _AddEvent(Event *event);
	bool _RemoveEvent(Event *event);
	Event *_EventAt(int32 index) const;
	int32 _IndexOfEvent(Event *event) const;
	int32 _FindInsertionIndex(bigtime_t time) const;

	static	int32 _EventLooperEntry(void *data);
	int32 _EventLooper();
	void _Reschedule();

	BList				fEvents;
	thread_id			fEventLooper;
	sem_id				fLooperControl;
	volatile bigtime_t	fNextEventTime;
	status_t			fStatus;
	volatile bool		fTerminating;
};

#endif	// EVENT_QUEUE_H