First pass at handling RTP header extension bit

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@3683 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/rtp.c b/rtp.c
index 51b500a..02b30bc 100755 (executable)
--- a/rtp.c
+++ b/rtp.c
@@ -396,6 +396,7 @@ struct ast_frame *ast_rtp_read(struct ast_rtp *rtp)
        int payloadtype;
        int hdrlen = 12;
        int mark;
+       int ext;
        char iabuf[INET_ADDRSTRLEN];
        unsigned int timestamp;
        unsigned int *rtpheader;
@@ -442,8 +443,14 @@ struct ast_frame *ast_rtp_read(struct ast_rtp *rtp)
        seqno = ntohl(rtpheader[0]);
        payloadtype = (seqno & 0x7f0000) >> 16;
        mark = seqno & (1 << 23);
+       ext = seqno & (1 << 28);
        seqno &= 0xffff;
        timestamp = ntohl(rtpheader[1]);
+       if (ext) {
+               /* RTP Extension present */
+               hdrlen += 4;
+               hdrlen += (rtpheader[3] & 0xffff) << 2;
+       }
 
 #if 0
        printf("Got RTP packet from %s:%d (type %d, seq %d, ts %d, len = %d)\n", ast_inet_ntoa(iabuf, sizeof(iabuf), sin.sin_addr), ntohs(sin.sin_port), payloadtype, seqno, timestamp,res - hdrlen);