Initial asymmetric codec support in MediaSessionDescription

webrtc/pc/mediasession.h

Index: webrtc/pc/mediasession.h
diff --git a/webrtc/pc/mediasession.h b/webrtc/pc/mediasession.h
index 39ac26bd8dad104c5b10b0d450caf7cf67e85233..a4e78bd6597a2f8c8e6e01208cc372c80d130886 100644
--- a/webrtc/pc/mediasession.h
+++ b/webrtc/pc/mediasession.h
@@ -52,6 +52,8 @@ enum MediaContentDirection {
   MD_SENDRECV
 };
 
+std::string MediaContentDirectionToString(MediaContentDirection direction);
+
 enum CryptoType {
   CT_NONE,
   CT_SDES,
@@ -395,8 +397,12 @@ class MediaSessionDescriptionFactory {
   MediaSessionDescriptionFactory(ChannelManager* cmanager,
                                  const TransportDescriptionFactory* factory);
 
-  const AudioCodecs& audio_codecs() const { return audio_codecs_; }
-  void set_audio_codecs(const AudioCodecs& codecs) { audio_codecs_ = codecs; }
+  const AudioCodecs& audio_codecs() const;

[pthatcher1, 2016/05/31 21:52:36]

I'd prefer audio_sendrecv_codecs()

[ossu, 2016/06/02 13:28:02]

Sure! I've addressed it in the second CL.

+  const AudioCodecs& audio_send_codecs() const;
+  const AudioCodecs& audio_recv_codecs() const;
+  void set_audio_codecs(const AudioCodecs& send_and_recv_codecs);
+  void set_audio_codecs(const AudioCodecs& send_codecs,
+                        const AudioCodecs& recv_codecs);

[pthatcher1, 2016/05/31 21:52:36]

This should probably both be SetAudioCodecs.

Also, why do we need the first version?  Can we just get rid of it?  It would be
much more clear to always provide send and recv and let this class do the
merging rather than get in a mix of letting the caller do the merge or letting
the class do the merge.

[ossu, 2016/06/02 13:28:02]

I've kept it while we're redoing the rest of the code to provide two lists and
separate factories for encode and decode. However, looking more closely these
setters are only called by unit tests. I'll take a look at changing them to use
the two-parameter version.

   void set_audio_rtp_header_extensions(const RtpHeaderExtensions& extensions) {
     audio_rtp_extensions_ = extensions;
   }
@@ -431,6 +437,9 @@ class MediaSessionDescriptionFactory {
 
  private:
   void GetCodecsToOffer(const SessionDescription* current_description,
+                        const AudioCodecs& supported_audio_codecs,
+                        const VideoCodecs& supported_video_codecs,
+                        const DataCodecs& supported_data_codecs,
                         AudioCodecs* audio_codecs,
                         VideoCodecs* video_codecs,
                         DataCodecs* data_codecs) const;
@@ -502,7 +511,9 @@ class MediaSessionDescriptionFactory {
       StreamParamsVec* current_streams,
       SessionDescription* answer) const;
 
-  AudioCodecs audio_codecs_;
+  AudioCodecs audio_send_codecs_;
+  AudioCodecs audio_recv_codecs_;
+  AudioCodecs audio_sendrecv_codecs_;
   RtpHeaderExtensions audio_rtp_extensions_;
   VideoCodecs video_codecs_;
   RtpHeaderExtensions video_rtp_extensions_;