static size_t rtp_write(void *ptr, size_t size, size_t nmemb, void *stream)
{
char *data = (char *)ptr;
int channel = RTP_PKT_CHANNEL(data);
int message_size;
int coded_size = RTP_PKT_LENGTH(data);
size_t failure = (size * nmemb) ? 0 : 1;
int i;
(void)stream;
message_size = curlx_uztosi(size * nmemb) - 4;
printf("RTP: message size %d, channel %d\n", message_size, channel);
if(message_size != coded_size) {
printf("RTP embedded size (%d) does not match the write size (%d).\n",
coded_size, message_size);
return failure;
}
data += 4;
for(i = 0; i < message_size; i+= RTP_DATA_SIZE) {
if(message_size - i > RTP_DATA_SIZE) {
if(memcmp(RTP_DATA, data + i, RTP_DATA_SIZE) != 0) {
printf("RTP PAYLOAD CORRUPTED [%s]\n", data + i);
return failure;
}
}
else {
if(memcmp(RTP_DATA, data + i, message_size - i) != 0) {
printf("RTP PAYLOAD END CORRUPTED (%d), [%s]\n",
message_size - i, data + i);
return failure;
}
}
}
rtp_packet_count++;
fprintf(stderr, "packet count is %d\n", rtp_packet_count);
return size * nmemb;
}
static CURLcode rtsp_rtp_readwrite(struct Curl_easy *data,
struct connectdata *conn,
ssize_t *nread,
bool *readmore) {
struct SingleRequest *k = &data->req;
struct rtsp_conn *rtspc = &(conn->proto.rtspc);
char *rtp; /* moving pointer to rtp data */
ssize_t rtp_dataleft; /* how much data left to parse in this round */
char *scratch;
CURLcode result;
if(rtspc->rtp_buf) {
/* There was some leftover data the last time. Merge buffers */
char *newptr = Curl_saferealloc(rtspc->rtp_buf,
rtspc->rtp_bufsize + *nread);
if(!newptr) {
rtspc->rtp_buf = NULL;
rtspc->rtp_bufsize = 0;
return CURLE_OUT_OF_MEMORY;
}
rtspc->rtp_buf = newptr;
memcpy(rtspc->rtp_buf + rtspc->rtp_bufsize, k->str, *nread);
rtspc->rtp_bufsize += *nread;
rtp = rtspc->rtp_buf;
rtp_dataleft = rtspc->rtp_bufsize;
}
else {
/* Just parse the request buffer directly */
rtp = k->str;
rtp_dataleft = *nread;
}
while((rtp_dataleft > 0) &&
(rtp[0] == '$')) {
if(rtp_dataleft > 4) {
int rtp_length;
/* Parse the header */
/* The channel identifier immediately follows and is 1 byte */
rtspc->rtp_channel = RTP_PKT_CHANNEL(rtp);
/* The length is two bytes */
rtp_length = RTP_PKT_LENGTH(rtp);
if(rtp_dataleft < rtp_length + 4) {
/* Need more - incomplete payload*/
*readmore = TRUE;
break;
}
/* We have the full RTP interleaved packet
* Write out the header including the leading '$' */
DEBUGF(infof(data, "RTP write channel %d rtp_length %d\n",
rtspc->rtp_channel, rtp_length));
result = rtp_client_write(conn, &rtp[0], rtp_length + 4);
if(result) {
failf(data, "Got an error writing an RTP packet");
*readmore = FALSE;
Curl_safefree(rtspc->rtp_buf);
rtspc->rtp_buf = NULL;
rtspc->rtp_bufsize = 0;
return result;
}
/* Move forward in the buffer */
rtp_dataleft -= rtp_length + 4;
rtp += rtp_length + 4;
if(data->set.rtspreq == RTSPREQ_RECEIVE) {
/* If we are in a passive receive, give control back
* to the app as often as we can.
*/
k->keepon &= ~KEEP_RECV;
}
}
else {
/* Need more - incomplete header */
*readmore = TRUE;
break;
}
}
if(rtp_dataleft != 0 && rtp[0] == '$') {
DEBUGF(infof(data, "RTP Rewinding %zd %s\n", rtp_dataleft,
*readmore ? "(READMORE)" : ""));
/* Store the incomplete RTP packet for a "rewind" */
scratch = malloc(rtp_dataleft);
if(!scratch) {
Curl_safefree(rtspc->rtp_buf);
rtspc->rtp_buf = NULL;
rtspc->rtp_bufsize = 0;
return CURLE_OUT_OF_MEMORY;
}
memcpy(scratch, rtp, rtp_dataleft);
Curl_safefree(rtspc->rtp_buf);
rtspc->rtp_buf = scratch;
rtspc->rtp_bufsize = rtp_dataleft;
/* As far as the transfer is concerned, this data is consumed */
*nread = 0;
return CURLE_OK;
}
/* Fix up k->str to point just after the last RTP packet */
k->str += *nread - rtp_dataleft;
/* either all of the data has been read or...
* rtp now points at the next byte to parse
*/
if(rtp_dataleft > 0)
DEBUGASSERT(k->str[0] == rtp[0]);
DEBUGASSERT(rtp_dataleft <= *nread); /* sanity check */
*nread = rtp_dataleft;
/* If we get here, we have finished with the leftover/merge buffer */
Curl_safefree(rtspc->rtp_buf);
rtspc->rtp_buf = NULL;
rtspc->rtp_bufsize = 0;
return CURLE_OK;
}