Bug 1571705 - Clarify mInputStream guarantees in MediaStreamTrack. r=karlt

Differential Revision: https://phabricator.services.mozilla.com/D41508

--HG--
extra : moz-landing-system : lando

dom/media/AudioStreamTrack.cpp

@@ -40,5 +40,10 @@ void AudioStreamTrack::GetLabel(nsAString& aLabel, CallerType aCallerType) {
   MediaStreamTrack::GetLabel(aLabel, aCallerType);
 }
 
+already_AddRefed<MediaStreamTrack> AudioStreamTrack::CloneInternal() {
+  return do_AddRef(new AudioStreamTrack(mWindow, mInputStream, mTrackID,
+                                        mSource, ReadyState(), mConstraints));
+}
+
 }  // namespace dom
 }  // namespace mozilla

dom/media/AudioStreamTrack.h

@@ -17,8 +17,9 @@ class AudioStreamTrack : public MediaStreamTrack {
   AudioStreamTrack(
       nsPIDOMWindowInner* aWindow, MediaStream* aInputStream, TrackID aTrackID,
       MediaStreamTrackSource* aSource,
+      MediaStreamTrackState aReadyState = MediaStreamTrackState::Live,
       const MediaTrackConstraints& aConstraints = MediaTrackConstraints())
-      : MediaStreamTrack(aWindow, aInputStream, aTrackID, aSource,
+      : MediaStreamTrack(aWindow, aInputStream, aTrackID, aSource, aReadyState,
                          aConstraints) {}
 
   AudioStreamTrack* AsAudioStreamTrack() override { return this; }
@@ -34,11 +35,7 @@ class AudioStreamTrack : public MediaStreamTrack {
   void GetLabel(nsAString& aLabel, CallerType aCallerType) override;
 
  protected:
-  already_AddRefed<MediaStreamTrack> CloneInternal() override {
-    return do_AddRef(
-        new AudioStreamTrack(mWindow, Ended() ? nullptr : mInputStream.get(),
-                             mTrackID, mSource, mConstraints));
-  }
+  already_AddRefed<MediaStreamTrack> CloneInternal() override;
 };
 
 }  // namespace dom

dom/media/MediaManager.cpp

@@ -1180,6 +1180,7 @@ class GetUserMediaStreamRunnable : public Runnable {
         MOZ_ASSERT(IsOn(mConstraints.mAudio));
         RefPtr<MediaStreamTrack> track = new dom::AudioStreamTrack(
             window, stream, kAudioTrack, audioTrackSource,
+            dom::MediaStreamTrackState::Live,
             GetInvariant(mConstraints.mAudio));
         domStream->AddTrackInternal(track);
       }
@@ -1193,6 +1194,7 @@ class GetUserMediaStreamRunnable : public Runnable {
         MOZ_ASSERT(IsOn(mConstraints.mVideo));
         RefPtr<MediaStreamTrack> track = new dom::VideoStreamTrack(
             window, stream, kVideoTrack, videoTrackSource,
+            dom::MediaStreamTrackState::Live,
             GetInvariant(mConstraints.mVideo));
         domStream->AddTrackInternal(track);
         switch (mVideoDevice->GetMediaSource()) {

dom/media/MediaStreamTrack.cpp

@@ -181,22 +181,24 @@ class MediaStreamTrack::TrackSink : public MediaStreamTrackSource::Sink {
 MediaStreamTrack::MediaStreamTrack(nsPIDOMWindowInner* aWindow,
                                    MediaStream* aInputStream, TrackID aTrackID,
                                    MediaStreamTrackSource* aSource,
+                                   MediaStreamTrackState aReadyState,
                                    const MediaTrackConstraints& aConstraints)
     : mWindow(aWindow),
       mInputStream(aInputStream),
-      mStream(mInputStream ? mInputStream->Graph()->CreateTrackUnionStream()
-                           : nullptr),
+      mStream(aReadyState == MediaStreamTrackState::Live
+                  ? mInputStream->Graph()->CreateTrackUnionStream()
+                  : nullptr),
       mPort(mStream ? mStream->AllocateInputPort(mInputStream) : nullptr),
       mTrackID(aTrackID),
       mSource(aSource),
       mSink(MakeUnique<TrackSink>(this)),
       mPrincipal(aSource->GetPrincipal()),
-      mReadyState(mStream ? MediaStreamTrackState::Live
-                          : MediaStreamTrackState::Ended),
+      mReadyState(aReadyState),
       mEnabled(true),
       mMuted(false),
       mConstraints(aConstraints) {
   if (!Ended()) {
+    MOZ_DIAGNOSTIC_ASSERT(!mInputStream->IsDestroyed());
     GetSource().RegisterSink(mSink.get());
 
     mMSGListener = new MSGListener(this);
@@ -499,7 +501,6 @@ already_AddRefed<MediaStreamTrack> MediaStreamTrack::Clone() {
   RefPtr<MediaStreamTrack> newTrack = CloneInternal();
   newTrack->SetEnabled(Enabled());
   newTrack->SetMuted(Muted());
-  MOZ_DIAGNOSTIC_ASSERT(newTrack->ReadyState() == ReadyState());
   return newTrack.forget();
 }
 
@@ -604,9 +605,7 @@ already_AddRefed<MediaInputPort> MediaStreamTrack::ForwardTrackContentsTo(
   MOZ_ASSERT(NS_IsMainThread());
   MOZ_RELEASE_ASSERT(aStream);
   MOZ_DIAGNOSTIC_ASSERT(!Ended());
-  RefPtr<MediaInputPort> port =
-      aStream->AllocateInputPort(mStream, mTrackID, mTrackID);
-  return port.forget();
+  return aStream->AllocateInputPort(mStream, mTrackID, mTrackID);
 }
 
 }  // namespace dom

dom/media/MediaStreamTrack.h

@@ -416,6 +416,7 @@ class MediaStreamTrack : public DOMEventTargetHelper,
   MediaStreamTrack(
       nsPIDOMWindowInner* aWindow, MediaStream* aInputStream, TrackID aTrackID,
       MediaStreamTrackSource* aSource,
+      MediaStreamTrackState aReadyState = MediaStreamTrackState::Live,
       const MediaTrackConstraints& aConstraints = MediaTrackConstraints());
 
   NS_DECL_ISUPPORTS_INHERITED
@@ -616,9 +617,9 @@ class MediaStreamTrack : public DOMEventTargetHelper,
   // We need this to track our parent object.
   nsCOMPtr<nsPIDOMWindowInner> mWindow;
 
-  // The input MediaStream assigned us by the data producer. Valid until we end.
+  // The input MediaStream assigned us by the data producer.
   // Owned by the producer.
-  RefPtr<MediaStream> mInputStream;
+  const RefPtr<MediaStream> mInputStream;
   // The MediaStream representing this MediaStreamTrack in the MediaStreamGraph.
   // Valid until we end. Owned by us.
   RefPtr<ProcessedMediaStream> mStream;

dom/media/VideoStreamTrack.cpp

@@ -17,9 +17,10 @@ namespace dom {
 VideoStreamTrack::VideoStreamTrack(nsPIDOMWindowInner* aWindow,
                                    MediaStream* aInputStream, TrackID aTrackID,
                                    MediaStreamTrackSource* aSource,
+                                   MediaStreamTrackState aReadyState,
                                    const MediaTrackConstraints& aConstraints)
-    : MediaStreamTrack(aWindow, aInputStream, aTrackID, aSource, aConstraints) {
-}
+    : MediaStreamTrack(aWindow, aInputStream, aTrackID, aSource, aReadyState,
+                       aConstraints) {}
 
 void VideoStreamTrack::Destroy() {
   mVideoOutputs.Clear();
@@ -79,5 +80,10 @@ void VideoStreamTrack::GetLabel(nsAString& aLabel, CallerType aCallerType) {
   MediaStreamTrack::GetLabel(aLabel, aCallerType);
 }
 
+already_AddRefed<MediaStreamTrack> VideoStreamTrack::CloneInternal() {
+  return do_AddRef(new VideoStreamTrack(mWindow, mInputStream, mTrackID,
+                                        mSource, ReadyState(), mConstraints));
+}
+
 }  // namespace dom
 }  // namespace mozilla

dom/media/VideoStreamTrack.h

@@ -21,6 +21,7 @@ class VideoStreamTrack : public MediaStreamTrack {
   VideoStreamTrack(
       nsPIDOMWindowInner* aWindow, MediaStream* aInputStream, TrackID aTrackID,
       MediaStreamTrackSource* aSource,
+      MediaStreamTrackState aState = MediaStreamTrackState::Live,
       const MediaTrackConstraints& aConstraints = MediaTrackConstraints());
 
   void Destroy() override;
@@ -39,11 +40,7 @@ class VideoStreamTrack : public MediaStreamTrack {
   void GetLabel(nsAString& aLabel, CallerType aCallerType) override;
 
  protected:
-  already_AddRefed<MediaStreamTrack> CloneInternal() override {
-    return do_AddRef(
-        new VideoStreamTrack(mWindow, Ended() ? nullptr : mInputStream.get(),
-                             mTrackID, mSource, mConstraints));
-  }
+  already_AddRefed<MediaStreamTrack> CloneInternal() override;
 
  private:
   nsTArray<RefPtr<VideoOutput>> mVideoOutputs;

media/webrtc/signaling/gtest/mediapipeline_unittest.cpp

@@ -55,7 +55,8 @@ class FakeMediaStreamTrackSource : public mozilla::dom::MediaStreamTrackSource {
 class FakeAudioStreamTrack : public mozilla::dom::AudioStreamTrack {
  public:
   FakeAudioStreamTrack()
-      : AudioStreamTrack(nullptr, nullptr, 0, new FakeMediaStreamTrackSource()),
+      : AudioStreamTrack(nullptr, nullptr, 0, new FakeMediaStreamTrackSource(),
+                         mozilla::dom::MediaStreamTrackState::Ended),
         mMutex("Fake AudioStreamTrack"),
         mStop(false),
         mCount(0) {