Move the streams concept into sdp_offer_answer

This makes it easier to see that the tying of tracks
to streams affects only the SDP negotiation, and not
what's sent on the wire.

Bug: webrtc:11995
Change-Id: I8ca5adf0050e4a2be55d164a6d0e4d5811582476
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/187359
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#32368}

Author: Harald Alvestrand

pc/peer_connection.cc

@@ -93,20 +93,6 @@ static const char kDefaultVideoSenderId[] = "defaultv0";
 
 static const int REPORT_USAGE_PATTERN_DELAY_MS = 60000;
 
-// Check if we can send |new_stream| on a PeerConnection.
-bool CanAddLocalMediaStream(webrtc::StreamCollectionInterface* current_streams,
-                            webrtc::MediaStreamInterface* new_stream) {
-  if (!new_stream || !current_streams) {
-    return false;
-  }
-  if (current_streams->find(new_stream->id()) != nullptr) {
-    RTC_LOG(LS_ERROR) << "MediaStream with ID " << new_stream->id()
-                      << " is already added.";
-    return false;
-  }
-  return true;
-}
-
 
 uint32_t ConvertIceTransportTypeToCandidateFilter(
     PeerConnectionInterface::IceTransportsType type) {
@@ -355,8 +341,6 @@ PeerConnection::PeerConnection(PeerConnectionFactory* factory,
     : factory_(factory),
       event_log_(std::move(event_log)),
       event_log_ptr_(event_log_.get()),
-      local_streams_(StreamCollection::Create()),
-      remote_streams_(StreamCollection::Create()),
       call_(std::move(call)),
       call_ptr_(call_.get()),
       sdp_handler_(this),
@@ -682,51 +666,23 @@ rtc::scoped_refptr<StreamCollectionInterface> PeerConnection::local_streams() {
   RTC_CHECK(!IsUnifiedPlan()) << "local_streams is not available with Unified "
                                  "Plan SdpSemantics. Please use GetSenders "
                                  "instead.";
-  return local_streams_;
+  return sdp_handler_.local_streams();
 }
 
 rtc::scoped_refptr<StreamCollectionInterface> PeerConnection::remote_streams() {
   RTC_DCHECK_RUN_ON(signaling_thread());
   RTC_CHECK(!IsUnifiedPlan()) << "remote_streams is not available with Unified "
                                  "Plan SdpSemantics. Please use GetReceivers "
                                  "instead.";
-  return remote_streams_;
+  return sdp_handler_.remote_streams();
 }
 
 bool PeerConnection::AddStream(MediaStreamInterface* local_stream) {
   RTC_DCHECK_RUN_ON(signaling_thread());
   RTC_CHECK(!IsUnifiedPlan()) << "AddStream is not available with Unified Plan "
                                  "SdpSemantics. Please use AddTrack instead.";
   TRACE_EVENT0("webrtc", "PeerConnection::AddStream");
-  if (IsClosed()) {
-    return false;
-  }
-  if (!CanAddLocalMediaStream(local_streams_, local_stream)) {
-    return false;
-  }
-
-  local_streams_->AddStream(local_stream);
-  MediaStreamObserver* observer = new MediaStreamObserver(local_stream);
-  observer->SignalAudioTrackAdded.connect(this,
-                                          &PeerConnection::OnAudioTrackAdded);
-  observer->SignalAudioTrackRemoved.connect(
-      this, &PeerConnection::OnAudioTrackRemoved);
-  observer->SignalVideoTrackAdded.connect(this,
-                                          &PeerConnection::OnVideoTrackAdded);
-  observer->SignalVideoTrackRemoved.connect(
-      this, &PeerConnection::OnVideoTrackRemoved);
-  stream_observers_.push_back(std::unique_ptr<MediaStreamObserver>(observer));
-
-  for (const auto& track : local_stream->GetAudioTracks()) {
-    AddAudioTrack(track.get(), local_stream);
-  }
-  for (const auto& track : local_stream->GetVideoTracks()) {
-    AddVideoTrack(track.get(), local_stream);
-  }
-
-  stats_->AddStream(local_stream);
-  sdp_handler_.UpdateNegotiationNeeded();
-  return true;
+  return sdp_handler_.AddStream(local_stream);
 }
 
 void PeerConnection::RemoveStream(MediaStreamInterface* local_stream) {
@@ -735,27 +691,7 @@ void PeerConnection::RemoveStream(MediaStreamInterface* local_stream) {
                                  "Plan SdpSemantics. Please use RemoveTrack "
                                  "instead.";
   TRACE_EVENT0("webrtc", "PeerConnection::RemoveStream");
-  if (!IsClosed()) {
-    for (const auto& track : local_stream->GetAudioTracks()) {
-      RemoveAudioTrack(track.get(), local_stream);
-    }
-    for (const auto& track : local_stream->GetVideoTracks()) {
-      RemoveVideoTrack(track.get(), local_stream);
-    }
-  }
-  local_streams_->RemoveStream(local_stream);
-  stream_observers_.erase(
-      std::remove_if(
-          stream_observers_.begin(), stream_observers_.end(),
-          [local_stream](const std::unique_ptr<MediaStreamObserver>& observer) {
-            return observer->stream()->id().compare(local_stream->id()) == 0;
-          }),
-      stream_observers_.end());
-
-  if (IsClosed()) {
-    return;
-  }
-  sdp_handler_.UpdateNegotiationNeeded();
+  sdp_handler_.RemoveStream(local_stream);
 }
 
 RTCErrorOr<rtc::scoped_refptr<RtpSenderInterface>> PeerConnection::AddTrack(
@@ -2027,6 +1963,7 @@ rtc::scoped_refptr<RtpReceiverInterface> PeerConnection::RemoveAndStopReceiver(
 
 void PeerConnection::AddAudioTrack(AudioTrackInterface* track,
                                    MediaStreamInterface* stream) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
   RTC_DCHECK(!IsClosed());
   RTC_DCHECK(track);
   RTC_DCHECK(stream);
@@ -2060,6 +1997,7 @@ void PeerConnection::AddAudioTrack(AudioTrackInterface* track,
 // indefinitely, when we have unified plan SDP.
 void PeerConnection::RemoveAudioTrack(AudioTrackInterface* track,
                                       MediaStreamInterface* stream) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
   RTC_DCHECK(!IsClosed());
   auto sender = FindSenderForTrack(track);
   if (!sender) {
@@ -2072,6 +2010,7 @@ void PeerConnection::RemoveAudioTrack(AudioTrackInterface* track,
 
 void PeerConnection::AddVideoTrack(VideoTrackInterface* track,
                                    MediaStreamInterface* stream) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
   RTC_DCHECK(!IsClosed());
   RTC_DCHECK(track);
   RTC_DCHECK(stream);
@@ -2097,6 +2036,7 @@ void PeerConnection::AddVideoTrack(VideoTrackInterface* track,
 
 void PeerConnection::RemoveVideoTrack(VideoTrackInterface* track,
                                       MediaStreamInterface* stream) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
   RTC_DCHECK(!IsClosed());
   auto sender = FindSenderForTrack(track);
   if (!sender) {
@@ -2262,13 +2202,13 @@ absl::optional<std::string> PeerConnection::GetDataMid() const {
 }
 
 void PeerConnection::OnRemoteSenderAdded(const RtpSenderInfo& sender_info,
+                                         MediaStreamInterface* stream,
                                          cricket::MediaType media_type) {
   RTC_DCHECK_RUN_ON(signaling_thread());
   RTC_LOG(LS_INFO) << "Creating " << cricket::MediaTypeToString(media_type)
                    << " receiver for track_id=" << sender_info.sender_id
                    << " and stream_id=" << sender_info.stream_id;
 
-  MediaStreamInterface* stream = remote_streams_->find(sender_info.stream_id);
   if (media_type == cricket::MEDIA_TYPE_AUDIO) {
     CreateAudioReceiver(stream, sender_info);
   } else if (media_type == cricket::MEDIA_TYPE_VIDEO) {
@@ -2279,14 +2219,13 @@ void PeerConnection::OnRemoteSenderAdded(const RtpSenderInfo& sender_info,
 }
 
 void PeerConnection::OnRemoteSenderRemoved(const RtpSenderInfo& sender_info,
+                                           MediaStreamInterface* stream,
                                            cricket::MediaType media_type) {
   RTC_DCHECK_RUN_ON(signaling_thread());
   RTC_LOG(LS_INFO) << "Removing " << cricket::MediaTypeToString(media_type)
                    << " receiver for track_id=" << sender_info.sender_id
                    << " and stream_id=" << sender_info.stream_id;
 
-  MediaStreamInterface* stream = remote_streams_->find(sender_info.stream_id);
-
   rtc::scoped_refptr<RtpReceiverInterface> receiver;
   if (media_type == cricket::MEDIA_TYPE_AUDIO) {
     // When the MediaEngine audio channel is destroyed, the RemoteAudioSource

pc/peer_connection.h

@@ -309,10 +309,6 @@ class PeerConnection : public PeerConnectionInternal,
     RTC_DCHECK_RUN_ON(signaling_thread());
     return &configuration_;
   }
-  rtc::scoped_refptr<StreamCollection> remote_streams_internal() const {
-    RTC_DCHECK_RUN_ON(signaling_thread());
-    return remote_streams_;
-  }
   absl::optional<std::string> sctp_mid() {
     RTC_DCHECK_RUN_ON(signaling_thread());
     return sctp_mid_s_;
@@ -389,16 +385,12 @@ class PeerConnection : public PeerConnectionInternal,
 
   // May be called either by AddStream/RemoveStream, or when a track is
   // added/removed from a stream previously added via AddStream.
-  void AddAudioTrack(AudioTrackInterface* track, MediaStreamInterface* stream)
-      RTC_RUN_ON(signaling_thread());
+  void AddAudioTrack(AudioTrackInterface* track, MediaStreamInterface* stream);
   void RemoveAudioTrack(AudioTrackInterface* track,
-                        MediaStreamInterface* stream)
-      RTC_RUN_ON(signaling_thread());
-  void AddVideoTrack(VideoTrackInterface* track, MediaStreamInterface* stream)
-      RTC_RUN_ON(signaling_thread());
+                        MediaStreamInterface* stream);
+  void AddVideoTrack(VideoTrackInterface* track, MediaStreamInterface* stream);
   void RemoveVideoTrack(VideoTrackInterface* track,
-                        MediaStreamInterface* stream)
-      RTC_RUN_ON(signaling_thread());
+                        MediaStreamInterface* stream);
 
   // AddTrack implementation when Unified Plan is specified.
   RTCErrorOr<rtc::scoped_refptr<RtpSenderInterface>> AddTrackUnifiedPlan(
@@ -503,12 +495,14 @@ class PeerConnection : public PeerConnectionInternal,
   // session description. It creates a remote MediaStreamTrackInterface
   // implementation and triggers CreateAudioReceiver or CreateVideoReceiver.
   void OnRemoteSenderAdded(const RtpSenderInfo& sender_info,
+                           MediaStreamInterface* stream,
                            cricket::MediaType media_type);
 
   // Triggered when a remote sender has been removed from a remote session
   // description. It removes the remote sender with id |sender_id| from a remote
   // MediaStream and triggers DestroyAudioReceiver or DestroyVideoReceiver.
   void OnRemoteSenderRemoved(const RtpSenderInfo& sender_info,
+                             MediaStreamInterface* stream,
                              cricket::MediaType media_type);
 
   // Triggered when a local sender has been seen for the first time in a local
@@ -764,16 +758,6 @@ class PeerConnection : public PeerConnectionInternal,
       tls_cert_verifier_;  // TODO(bugs.webrtc.org/9987): Accessed on both
                            // signaling and network thread.
 
-  // Streams added via AddStream.
-  const rtc::scoped_refptr<StreamCollection> local_streams_
-      RTC_GUARDED_BY(signaling_thread());
-  // Streams created as a result of SetRemoteDescription.
-  const rtc::scoped_refptr<StreamCollection> remote_streams_
-      RTC_GUARDED_BY(signaling_thread());
-
-  std::vector<std::unique_ptr<MediaStreamObserver>> stream_observers_
-      RTC_GUARDED_BY(signaling_thread());
-
   // These lists store sender info seen in local/remote descriptions.
   std::vector<RtpSenderInfo> remote_audio_sender_infos_
       RTC_GUARDED_BY(signaling_thread());