/*
* dmxdev.c - DVB demultiplexer device
*
* Copyright (C) 2000 Ralph Metzler & Marcus Metzler
* 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/sched.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/ioctl.h>
#include <linux/wait.h>
#include <asm/uaccess.h>
#include "dmxdev.h"
static int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off debugging (default:off).");
#define dprintk if (debug) printk
static int dvb_dmxdev_buffer_write(struct dvb_ringbuffer *buf,
const u8 *src, size_t len)
{
ssize_t free;
if (!len)
return 0;
if (!buf->data)
return 0;
free = dvb_ringbuffer_free(buf);
if (len > free) {
dprintk("dmxdev: buffer overflow\n");
return -EOVERFLOW;
}
return dvb_ringbuffer_write(buf, src, len);
}
static ssize_t dvb_dmxdev_buffer_read(struct dvb_ringbuffer *src,
int non_blocking, char __user *buf,
size_t count, loff_t *ppos)
{
size_t todo;
ssize_t avail;
ssize_t ret = 0;
if (!src->data)
return 0;
if (src->error) {
ret = src->error;
dvb_ringbuffer_flush(src);
return ret;
}
for (todo = count; todo > 0; todo -= ret) {
if (non_blocking && dvb_ringbuffer_empty(src)) {
ret = -EWOULDBLOCK;
break;
}
ret = wait_event_interruptible(src->queue,
!dvb_ringbuffer_empty(src) ||
(src->error != 0));
if (ret < 0)
break;
if (src->error) {
ret = src->error;
dvb_ringbuffer_flush(src);
break;
}
avail = dvb_ringbuffer_avail(src);
if (avail > todo)
avail = todo;
ret = dvb_ringbuffer_read_user(src, 