static ssize_t ci_ll_read(struct dvb_ringbuffer *cibuf, struct file *file,
char __user *buf, size_t count, loff_t *ppos)
{
int avail;
int non_blocking = file->f_flags & O_NONBLOCK;
ssize_t len;
if (!cibuf->data || !count)
return 0;
if (non_blocking && (dvb_ringbuffer_empty(cibuf)))
return -EWOULDBLOCK;
if (wait_event_interruptible(cibuf->queue,
!dvb_ringbuffer_empty(cibuf)))
return -ERESTARTSYS;
avail = dvb_ringbuffer_avail(cibuf);
if (avail < 4)
return 0;
len = DVB_RINGBUFFER_PEEK(cibuf, 0) << 8;
len |= DVB_RINGBUFFER_PEEK(cibuf, 1);
if (avail < len + 2 || count < len)
return -EINVAL;
DVB_RINGBUFFER_SKIP(cibuf, 2);
return dvb_ringbuffer_read_user(cibuf, buf, len);
}
int mpq_streambuffer_data_read_dispose(
struct mpq_streambuffer *sbuff,
size_t len)
{
if (NULL == sbuff)
return -EINVAL;
if (MPQ_STREAMBUFFER_BUFFER_MODE_RING == sbuff->mode) {
if (unlikely(dvb_ringbuffer_avail(&sbuff->raw_data) < len))
return -EINVAL;
DVB_RINGBUFFER_SKIP(&sbuff->raw_data, len);
wake_up_all(&sbuff->raw_data.queue);
} else {
struct mpq_streambuffer_buffer_desc *desc;
desc = (struct mpq_streambuffer_buffer_desc *)
&sbuff->raw_data.data[sbuff->raw_data.pread];
if ((desc->read_ptr + len) > desc->size)
desc->read_ptr = desc->size;
else
desc->read_ptr += len;
}
return 0;
}
int mpq_streambuffer_pkt_dispose(
struct mpq_streambuffer *sbuff,
size_t idx,
int dispose_data)
{
int ret;
struct mpq_streambuffer_packet_header packet;
if (NULL == sbuff)
return -EINVAL;
/* read-out the packet header first */
ret = dvb_ringbuffer_pkt_read(&sbuff->packet_data, idx,
0,
(u8 *)&packet,
sizeof(struct mpq_streambuffer_packet_header));
if (ret != sizeof(struct mpq_streambuffer_packet_header))
return -EINVAL;
if ((MPQ_STREAMBUFFER_BUFFER_MODE_LINEAR == sbuff->mode) ||
(dispose_data)) {
/* Advance the read pointer in the raw-data buffer first */
ret = mpq_streambuffer_data_read_dispose(sbuff,
packet.raw_data_len);
if (ret != 0)
return ret;
}
/* Move read pointer to the next linear buffer for subsequent reads */
if ((MPQ_STREAMBUFFER_BUFFER_MODE_LINEAR == sbuff->mode) &&
(packet.raw_data_len > 0)) {
struct mpq_streambuffer_buffer_desc *desc;
desc = (struct mpq_streambuffer_buffer_desc *)
&sbuff->raw_data.data[sbuff->raw_data.pread];
desc->write_ptr = 0;
desc->read_ptr = 0;
DVB_RINGBUFFER_SKIP(&sbuff->raw_data,
sizeof(struct mpq_streambuffer_buffer_desc));
sbuff->pending_buffers_count--;
wake_up_all(&sbuff->raw_data.queue);
}
/* Now clear the packet from the packet header */
dvb_ringbuffer_pkt_dispose(&sbuff->packet_data, idx);
if (sbuff->cb)
sbuff->cb(sbuff, sbuff->cb_user_data);
return 0;
}
void dvb_ringbuffer_pkt_dispose(struct dvb_ringbuffer *rbuf, size_t idx)
{
size_t pktlen;
rbuf->data[(idx + 2) % rbuf->size] = PKT_DISPOSED;
// clean up disposed packets
while(dvb_ringbuffer_avail(rbuf) > DVB_RINGBUFFER_PKTHDRSIZE) {
if (DVB_RINGBUFFER_PEEK(rbuf, 2) == PKT_DISPOSED) {
pktlen = DVB_RINGBUFFER_PEEK(rbuf, 0) << 8;
pktlen |= DVB_RINGBUFFER_PEEK(rbuf, 1);
DVB_RINGBUFFER_SKIP(rbuf, pktlen + DVB_RINGBUFFER_PKTHDRSIZE);
} else {
// first packet is not disposed, so we stop cleaning now
break;
}
}
}