omsbuff_ref.c

linux下的rtp的实例源代码

/* * 
 *  $Id: OMSbuff_ref.c 329 2006-03-29 08:45:40Z shawill $
 *  
 *  This file is part of Fenice
 *
 *  Fenice -- Open Media Server
 *
 *  Copyright (C) 2004 by
 *  	
 *	- Giampaolo Mancini	<[e-mail]>
 *	- Francesco Varano	<[e-mail]>
 *	- Marco Penno		<[e-mail]>
 *	- Federico Ridolfo	<[e-mail]>
 *	- Eugenio Menegatti 	<[e-mail]>
 *	- Stefano Cau
 *	- Giuliano Emma
 *	- Stefano Oldrini
 * 
 *  Fenice 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.
 *
 *  Fenice 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 Fenice; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *  
 * */

#include <stdio.h>
#include <stdlib.h>

#include <sys/mman.h>

#include <fenice/bufferpool.h>
#include <fenice/fnc_log.h>

/* ! Add and return a new consumer reference to the buffer,
 * \return NULL if an error occurs*/
OMSConsumer *OMSbuff_ref(OMSBuffer *buffer)
{
	OMSConsumer *cons;
	ptrdiff_t i;
	
	if (!buffer) return NULL;
	
	if ((cons = (OMSConsumer *)malloc(sizeof(OMSConsumer))) == NULL )
		return NULL;
	
	cons->last_read_pos = -1;// OMStoSlotPtr(buffer, NULL);
	cons->buffer = buffer;
	cons->frames=0;
	cons->firstts = -1;
	
	OMSbuff_lock(buffer);
//	cons->read_pos = buffer->slots[buffer->control->write_pos].next;
//	cons->last_seq = buffer->slots[buffer->control->write_pos].slot_seq;
	cons->read_pos = buffer->control->valid_read_pos; // buffer->slots[buffer->control->valid_read_pos].next;
	cons->last_seq = 0; // buffer->slots[buffer->control->valid_read_pos].slot_seq;

	if (buffer->slots[cons->read_pos].slot_seq) {
		for (i=cons->read_pos; i!=buffer->control->write_pos; i=buffer->slots[i].next)
			buffer->slots[i].refs++;
		buffer->slots[i].refs++;
	}
	printf("ref at position %d (write_pos @ %d)\n", cons->read_pos, buffer->control->write_pos);
	buffer->control->refs++;
	
//	if ( msync(buffer->control, sizeof(OMSControl), MS_SYNC) )
//		printf("*** control msync error\n");
	OMSbuff_unlock(buffer);
		
	fnc_log(FNC_LOG_DEBUG, "Buffer ref (%d)\n", buffer->control->refs);

	return cons;
}