From be2e5f78b3498858cd8694fa6d00a28ba8093f26 Mon Sep 17 00:00:00 2001
From: Steve Anton <steveanton@webrtc.org>
Date: Fri, 6 Sep 2019 16:26:02 -0700
Subject: [PATCH] Make payload type demux conditional on media direction

Bug: webrtc:10139
Change-Id: I6803f4325e7c34915a9ae79e3360a787a7a9df5c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/149173
Reviewed-by: Steve Anton <steveanton@webrtc.org>
Commit-Queue: Steve Anton <steveanton@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29105}
---
 pc/channel.cc | 58 ++++++++++++++++++++++++++++++++++++++-------------
 pc/channel.h  |  2 ++
 2 files changed, 46 insertions(+), 14 deletions(-)

diff --git a/pc/channel.cc b/pc/channel.cc
index caf8c93956..95be5b65fb 100644
--- a/pc/channel.cc
+++ b/pc/channel.cc
@@ -770,6 +770,10 @@ void BaseChannel::AddHandledPayloadType(int payload_type) {
   demuxer_criteria_.payload_types.insert(static_cast<uint8_t>(payload_type));
 }
 
+void BaseChannel::ClearHandledPayloadTypes() {
+  demuxer_criteria_.payload_types.clear();
+}
+
 void BaseChannel::FlushRtcpMessages_n() {
   // Flush all remaining RTCP messages. This should only be called in
   // destructor.
@@ -889,13 +893,16 @@ bool VoiceChannel::SetLocalContent_w(const MediaContentDescription* content,
                  error_desc);
     return false;
   }
-  for (const AudioCodec& codec : audio->codecs()) {
-    AddHandledPayloadType(codec.id);
-  }
-  // Need to re-register the sink to update the handled payload.
-  if (!RegisterRtpDemuxerSink()) {
-    RTC_LOG(LS_ERROR) << "Failed to set up audio demuxing.";
-    return false;
+
+  if (webrtc::RtpTransceiverDirectionHasRecv(audio->direction())) {
+    for (const AudioCodec& codec : audio->codecs()) {
+      AddHandledPayloadType(codec.id);
+    }
+    // Need to re-register the sink to update the handled payload.
+    if (!RegisterRtpDemuxerSink()) {
+      RTC_LOG(LS_ERROR) << "Failed to set up audio demuxing.";
+      return false;
+    }
   }
 
   last_recv_params_ = recv_params;
@@ -945,6 +952,16 @@ bool VoiceChannel::SetRemoteContent_w(const MediaContentDescription* content,
   }
   last_send_params_ = send_params;
 
+  if (!webrtc::RtpTransceiverDirectionHasSend(content->direction())) {
+    RTC_DLOG(LS_VERBOSE) << "SetRemoteContent_w: remote side will not send - "
+                            "disable payload type demuxing";
+    ClearHandledPayloadTypes();
+    if (!RegisterRtpDemuxerSink()) {
+      RTC_LOG(LS_ERROR) << "Failed to update audio demuxing.";
+      return false;
+    }
+  }
+
   // TODO(pthatcher): Move remote streams into AudioRecvParameters,
   // and only give it to the media channel once we have a local
   // description too (without a local description, we won't be able to
@@ -1047,13 +1064,16 @@ bool VideoChannel::SetLocalContent_w(const MediaContentDescription* content,
                  error_desc);
     return false;
   }
-  for (const VideoCodec& codec : video->codecs()) {
-    AddHandledPayloadType(codec.id);
-  }
-  // Need to re-register the sink to update the handled payload.
-  if (!RegisterRtpDemuxerSink()) {
-    RTC_LOG(LS_ERROR) << "Failed to set up video demuxing.";
-    return false;
+
+  if (webrtc::RtpTransceiverDirectionHasRecv(video->direction())) {
+    for (const VideoCodec& codec : video->codecs()) {
+      AddHandledPayloadType(codec.id);
+    }
+    // Need to re-register the sink to update the handled payload.
+    if (!RegisterRtpDemuxerSink()) {
+      RTC_LOG(LS_ERROR) << "Failed to set up video demuxing.";
+      return false;
+    }
   }
 
   last_recv_params_ = recv_params;
@@ -1140,6 +1160,16 @@ bool VideoChannel::SetRemoteContent_w(const MediaContentDescription* content,
     last_recv_params_ = recv_params;
   }
 
+  if (!webrtc::RtpTransceiverDirectionHasSend(content->direction())) {
+    RTC_DLOG(LS_VERBOSE) << "SetRemoteContent_w: remote side will not send - "
+                            "disable payload type demuxing";
+    ClearHandledPayloadTypes();
+    if (!RegisterRtpDemuxerSink()) {
+      RTC_LOG(LS_ERROR) << "Failed to update video demuxing.";
+      return false;
+    }
+  }
+
   // TODO(pthatcher): Move remote streams into VideoRecvParameters,
   // and only give it to the media channel once we have a local
   // description too (without a local description, we won't be able to
diff --git a/pc/channel.h b/pc/channel.h
index 8a75a1a5f3..5222d98eed 100644
--- a/pc/channel.h
+++ b/pc/channel.h
@@ -281,6 +281,8 @@ class BaseChannel : public ChannelInterface,
 
   void AddHandledPayloadType(int payload_type);
 
+  void ClearHandledPayloadTypes();
+
   void UpdateRtpHeaderExtensionMap(
       const RtpHeaderExtensions& header_extensions);