sjero.net Git - linphone/blob - coreapi/offeranswer.c

   1 /*
   2 linphone
   3 Copyright (C) 2010  Simon MORLAT (simon.morlat@free.fr)
   4
   5 This program is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU General Public License
   7 as published by the Free Software Foundation; either version 2
   8 of the License, or (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18 */
  19
  20 #include "sal.h"
  21 #include "offeranswer.h"
  22
  23
  24 static PayloadType * find_payload_type_best_match(const MSList *l, const PayloadType *refpt){
  25         PayloadType *pt;
  26         char value[10];
  27         const MSList *elem;
  28         PayloadType *candidate=NULL;
  29
  30         for (elem=l;elem!=NULL;elem=elem->next){
  31                 pt=(PayloadType*)elem->data;
  32                 if (strcasecmp(pt->mime_type,refpt->mime_type)==0 && pt->clock_rate==refpt->clock_rate){
  33                         candidate=pt;
  34                         /*good candidate, check fmtp for H264 */
  35                         if (strcasecmp(pt->mime_type,"H264")==0){
  36                                 if (pt->recv_fmtp!=NULL && refpt->recv_fmtp!=NULL){
  37                                         int mode1=0,mode2=0;
  38                                         if (fmtp_get_value(pt->recv_fmtp,"packetization-mode",value,sizeof(value))){
  39                                                 mode1=atoi(value);
  40                                         }
  41                                         if (fmtp_get_value(refpt->recv_fmtp,"packetization-mode",value,sizeof(value))){
  42                                                 mode2=atoi(value);
  43                                         }
  44                                         if (mode1==mode2)
  45                                             break; /*exact match */
  46                                 }
  47                         }else break;
  48                 }
  49         }
  50         return candidate;
  51 }
  52
  53 static MSList *match_payloads(const MSList *local, const MSList *remote){
  54         const MSList *e2;
  55         MSList *res=NULL;
  56         PayloadType *matched;
  57         for(e2=remote;e2!=NULL;e2=e2->next){
  58                 PayloadType *p2=(PayloadType*)e2->data;
  59                 matched=find_payload_type_best_match(local,p2);
  60                 if (matched){
  61                         matched=payload_type_clone(matched);
  62                         if (p2->recv_fmtp)
  63                                 payload_type_set_send_fmtp(matched,p2->recv_fmtp);
  64                         res=ms_list_append(res,matched);
  65                         payload_type_set_number(matched,payload_type_get_number(p2));
  66                 }else{
  67                         ms_message("No match for %s/%i",p2->mime_type,p2->clock_rate);
  68                 }
  69         }
  70         return res;
  71 }
  72
  73 static bool_t only_telephone_event(const MSList *l){
  74         for(;l!=NULL;l=l->next){
  75                 PayloadType *p=(PayloadType*)l->data;
  76                 if (strcasecmp(p->mime_type,"telephone-event")!=0){
  77                         return FALSE;
  78                 }
  79         }
  80         return TRUE;
  81 }
  82
  83 static void initiate_outgoing(const SalStreamDescription *local_offer,
  84                                         const SalStreamDescription *remote_answer,
  85                                         SalStreamDescription *result){
  86         result->payloads=match_payloads(local_offer->payloads,remote_answer->payloads);
  87         if (result->payloads && !only_telephone_event(result->payloads)){
  88                 result->port=remote_answer->port;
  89                 result->bandwidth=remote_answer->bandwidth;
  90                 result->ptime=remote_answer->ptime;
  91         }else{
  92                 result->port=0;
  93         }
  94 }
  95
  96
  97 static void initiate_incoming(const SalStreamDescription *local_cap,
  98                                         const SalStreamDescription *remote_offer,
  99                                         SalStreamDescription *result){
 100         result->payloads=match_payloads(local_cap->payloads,remote_offer->payloads);
 101         if (result->payloads && !only_telephone_event(result->payloads)){
 102                 result->port=remote_offer->port;
 103                 result->bandwidth=remote_offer->bandwidth;
 104                 result->ptime=remote_offer->ptime;
 105         }else{
 106                 result->port=0;
 107         }
 108 }
 109
 110 /**
 111  * Returns a media description to run the streams with, based on a local offer
 112  * and the returned response (remote).
 113 **/
 114 int offer_answer_initiate_outgoing(const SalMediaDescription *local_offer,
 115                                                                         const SalMediaDescription *remote_answer,
 116                                                         SalMediaDescription *result){
 117     int i;
 118     for(i=0;i<local_offer->nstreams;++i){
 119         initiate_outgoing(&local_offer->streams[i],&remote_answer->streams[i],&result->streams[i]);
 120     }
 121         result->nstreams=local_offer->nstreams;
 122         strcpy(result->addr,remote_answer->addr);
 123         return 0;
 124 }
 125
 126 /**
 127  * Returns a media description to run the streams with, based on the local capabilities and
 128  * and the received offer.
 129  * The returned media description is an answer and should be sent to the offerer.
 130 **/
 131 int offer_answer_initiate_incoming(const SalMediaDescription *local_capabilities,
 132                                                 const SalMediaDescription *remote_offer,
 133                                         SalMediaDescription *result){
 134     int i;
 135     for(i=0;i<local_capabilities->nstreams;++i){
 136         initiate_incoming(&local_capabilities->streams[i],&remote_offer->streams[i],&result->streams[i]);
 137     }
 138         result->nstreams=local_capabilities->nstreams;
 139         strcpy(result->addr,remote_offer->addr);
 140         return 0;
 141 }
 142