path: root/drivers/media/dvb/dvb-core/dvb_demux.c

/*
 * dvb_demux.c - DVB kernel demux API
 *
 * Copyright (C) 2000-2001 Ralph  Metzler <ralph@convergence.de>
 *		       & Marcus Metzler <marcus@convergence.de>
 *			 for convergence integrated media GmbH
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1
 * 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 Lesser General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/string.h>
#include <linux/crc32.h>
#include <asm/uaccess.h>

#include "dvb_demux.h"

#define NOBUFS
/*
** #define DVB_DEMUX_SECTION_LOSS_LOG to monitor payload loss in the syslog
*/
// #define DVB_DEMUX_SECTION_LOSS_LOG

/******************************************************************************
 * static inlined helper functions
 ******************************************************************************/

static inline u16 section_length(const u8 *buf)
{
	return 3 + ((buf[1] & 0x0f) << 8) + buf[2];
}

static inline u16 ts_pid(const u8 *buf)
{
	return ((buf[1] & 0x1f) << 8) + buf[2];
}

static inline u8 payload(const u8 *tsp)
{
	if (!(tsp[3] & 0x10))	// no payload?
		return 0;

	if (tsp[3] & 0x20) {	// adaptation field?
		if (tsp[4] > 183)	// corrupted data?
			return 0;
		else
			return 184 - 1 - tsp[4];
	}

	return 184;
}

static u32 dvb_dmx_crc32(struct dvb_demux_feed *f, const u8 *src, size_t len)
{
	return (f->feed.sec.crc_val = crc32_be(f->feed.sec.crc_val, src, len));
}

static void dvb_dmx_memcopy(struct dvb_demux_feed *f, u8 *d, const u8 *s,
			    size_t len)
{
	memcpy(d, s, len);
}

/******************************************************************************
 * Software filter functions
 ******************************************************************************/

static inline int dvb_dmx_swfilter_payload(struct dvb_demux_feed *feed,
					   const u8 *buf)
{
	int count = payload(buf);
	int p;
	//int ccok;
	//u8 cc;

	if (count == 0)
		return -1;

	p = 188 - count;

	/*
	cc = buf[3] & 0x0f;
	ccok = ((feed->cc + 1) & 0x0f) == cc;
	feed->cc = cc;
	if (!ccok)
		printk("missed packet!\n");
	*/

	if (buf[1] & 0x40)	// PUSI ?
		feed->peslen = 0xfffa;

	feed->peslen += count;

	return feed->cb.ts(&buf[p], count, NULL, 0, &feed->feed.ts, DMX_OK);
}

static int dvb_dmx_swfilter_sectionfilter(struct dvb_demux_feed *