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/*
The oRTP library is an RTP (Realtime Transport Protocol - rfc1889) stack.
Copyright (C) 2001 Simon MORLAT simon.morlat@linphone.org
This source code file was written by Nicola Baldo as an extension of
the oRTP library. Copyright (C) 2005 Nicola Baldo nicola@baldo.biz
This library 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 library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <ortp.h>
void report_block_parse(RtpSession *session, report_block_t *rb, struct timeval rcv_time_tv)
{
rb->ssrc = ntohl(rb->ssrc);
if ( rb->ssrc != session->send_ssrc )
{
ortp_debug("Received rtcp report block related to unknown ssrc (not from us)... discarded");
return;
}
else
{
guint32 rcv_time_msw;
guint32 rcv_time_lsw;
guint32 rcv_time;
double rtt;
rcv_time_msw = rcv_time_tv.tv_sec;
rcv_time_lsw = (guint32) ((double)rcv_time_tv.tv_usec*(double)(1LL<<32)*1.0e-6);
rcv_time = (rcv_time_msw<<16) | (rcv_time_lsw >> 16);
rb->cum_num_packet_lost = ntoh24(rb->cum_num_packet_lost);
rb->ext_high_seq_num_rec = ntohl(rb->ext_high_seq_num_rec);
rb->interarrival_jitter = ntohl(rb->interarrival_jitter);
rb->lsr = ntohl(rb->lsr);
rb->delay_snc_last_sr = ntohl(rb->delay_snc_last_sr);
/* calculating Round Trip Time*/
if (rb->lsr != 0)
{
rtt = (double) (rcv_time - rb->delay_snc_last_sr - rb->lsr);
rtt = rtt/65536;
//printf("RTT = %f s\n",rtt);
}
}
}
void rtcp_parse(RtpSession *session, mblk_t *mp)
{
rtcp_common_header_t *rtcp;
int msgsize;
int rtcp_pk_size;
RtpStream *rtpstream=&session->rtp;
struct timeval rcv_time_tv;
gettimeofday(&rcv_time_tv,NULL);
g_return_if_fail(mp!=NULL);
msgsize=mp->b_wptr-mp->b_rptr;
if (msgsize < RTCP_COMMON_HEADER_SIZE)
{
ortp_debug("Receiving too short rtcp packet... discarded");
return;
}
rtcp=(rtcp_common_header_t *)mp->b_rptr;
/* compound rtcp packet can be composed by more than one rtcp message */
while (msgsize >= RTCP_COMMON_HEADER_SIZE)
{
if (rtcp->version!=2)
{
ortp_debug("Receiving rtcp packet with version number !=2...discarded");
return;
}
/* convert header data from network order to host order */
rtcp->length = ntohs(rtcp->length);
switch (rtcp->packet_type)
{
case RTCP_SR:
{
rtcp_sr_t *sr = (rtcp_sr_t *) rtcp;
report_block_t *rb;
int i;
if ( ntohl(sr->ssrc) != session->recv_ssrc )
{
ortp_debug("Receiving rtcp sr packet from unknown ssrc.. discarded");
return;
}
if (msgsize < RTCP_COMMON_HEADER_SIZE + RTCP_SSRC_FIELD_SIZE + RTCP_SENDER_INFO_SIZE + (RTCP_REPORT_BLOCK_SIZE*sr->ch.rc))
{
ortp_debug("Receiving too short rtcp sr packet... discarded");
return;
}
/* parsing RTCP Sender Info */
sr->si.ntp_timestamp_msw = ntohl(sr->si.ntp_timestamp_msw);
sr->si.ntp_timestamp_lsw = ntohl(sr->si.ntp_timestamp_lsw);
sr->si.rtp_timestamp = ntohl(sr->si.rtp_timestamp);
sr->si.senders_packet_count = ntohl(sr->si.senders_packet_count);
sr->si.senders_octet_count = ntohl(sr->si.senders_octet_count);
/* saving data to fill LSR and DLSR field in next RTCP report to be transmitted */
rtpstream->last_rcv_SR_ts = (sr->si.ntp_timestamp_msw << 16) | (sr->si.ntp_timestamp_lsw >> 16);
rtpstream->last_rcv_SR_time.tv_usec = rcv_time_tv.tv_usec;
rtpstream->last_rcv_SR_time.tv_sec = rcv_time_tv.tv_sec;
/* parsing all RTCP report blocks */
for (i=0; i<sr->ch.rc; i++)
{
rb = &(sr->rb[i]);
report_block_parse(session, rb, rcv_time_tv);
}
}
break;
case RTCP_RR:
{
rtcp_rr_t *rr = (rtcp_rr_t *) rtcp;
report_block_t *rb;
int i;
if ( ntohl(rr->ssrc) != session->recv_ssrc )
{
ortp_debug("Receiving rtcp rr packet from unknown ssrc.. discarded");
return;
}
if (msgsize < RTCP_COMMON_HEADER_SIZE + RTCP_SSRC_FIELD_SIZE + (RTCP_REPORT_BLOCK_SIZE*rr->ch.rc))
{
ortp_debug("Receiving too short rtcp sr packet... discarded");
return;
}
/* parsing all RTCP report blocks */
for (i=0; i<rr->ch.rc; i++)
{
rb = &(rr->rb[i]);
report_block_parse(session, rb, rcv_time_tv);
}
}
break;
case RTCP_SDES:
/* to be implemented */
break;
case RTCP_BYE:
/* to be implemented */
break;
case RTCP_APP:
/* to be implemented */
break;
default:
ortp_debug("Receiving unknown rtcp packet type... discarded");
return;
}
rtcp_pk_size = ((rtcp->length)+1)*4; /* current RTCP packet size, in octets */
msgsize -= rtcp_pk_size; /* size of unparsed portion of UDP packet, in octets */
rtcp = (rtcp_common_header_t *) (rtcp_pk_size + (char *) rtcp); /* pointer to next RTCP packet in current UDP packet */
}
}
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