A.5 Parsing RTCP SDES Packets

This function parses an SDES packet, calling functions find_member() to find a pointer to the information for a session member given the SSRC identifier and member_sdes() to store the new SDES information for that member. This function expects a pointer to the header of the RTCP packet.

   void rtp_read_sdes(rtcp_t *r)
   {
       int count = r->common.count;
       rtcp_sdes_t *sd = &r->r.sdes;
       rtcp_sdes_item_t *rsp, *rspn;
       rtcp_sdes_item_t *end = (rtcp_sdes_item_t *)
                               ((u_int32 *)r + r->common.length + 1);
       source *s;

       while (--count >= 0) {
           rsp = &sd->item[0];
           if (rsp >= end) break;
           s = find_member(sd->src);

           for (; rsp->type; rsp = rspn ) {
               rspn = (rtcp_sdes_item_t *)((char*)rsp+rsp->length+2);
               if (rspn >= end) {
                   rsp = rspn;
                   break;
               }
               member_sdes(s, rsp->type, rsp->data, rsp->length);
           }
           sd = (rtcp_sdes_t *)
                ((u_int32 *)sd + (((char *)rsp - (char *)sd) >> 2)+1);
       }
       if (count >= 0) {
           /* invalid packet format */
       }
   }