Bug 1204430. Part 2 - mirror MediaDecoder::mMediaSeekable. r=kinetik.

dom/media/MediaDecoder.cpp

@@ -351,7 +351,6 @@ MediaDecoder::MediaDecoder() :
   mDormantSupported(false),
   mLogicalPosition(0.0),
   mDuration(std::numeric_limits<double>::quiet_NaN()),
-  mMediaSeekable(true),
   mReentrantMonitor("media.decoder"),
   mIgnoreProgressData(false),
   mInfiniteStream(false),
@@ -407,7 +406,9 @@ MediaDecoder::MediaDecoder() :
   mPlaybackRateReliable(AbstractThread::MainThread(), true,
                         "MediaDecoder::mPlaybackRateReliable (Canonical)"),
   mDecoderPosition(AbstractThread::MainThread(), 0,
-                   "MediaDecoder::mDecoderPosition (Canonical)")
+                   "MediaDecoder::mDecoderPosition (Canonical)"),
+  mMediaSeekable(AbstractThread::MainThread(), true,
+                 "MediaDecoder::mMediaSeekable (Canonical)")
 {
   MOZ_COUNT_CTOR(MediaDecoder);
   MOZ_ASSERT(NS_IsMainThread());
@@ -1124,8 +1125,8 @@ MediaDecoder::IsTransportSeekable()
 
 bool MediaDecoder::IsMediaSeekable()
 {
+  MOZ_ASSERT(NS_IsMainThread());
   NS_ENSURE_TRUE(GetStateMachine(), false);
-  ReentrantMonitorAutoEnter mon(GetReentrantMonitor());
   return mMediaSeekable;
 }
 

dom/media/MediaDecoder.h

@@ -801,9 +801,6 @@ protected:
   // Official duration of the media resource as observed by script.
   double mDuration;
 
-  // True if the media is seekable (i.e. supports random access).
-  bool mMediaSeekable;
-
   /******
    * The following member variables can be accessed from any thread.
    ******/
@@ -1001,6 +998,9 @@ protected:
   // back again.
   Canonical<int64_t> mDecoderPosition;
 
+  // True if the media is seekable (i.e. supports random access).
+  Canonical<bool> mMediaSeekable;
+
 public:
   AbstractCanonical<media::NullableTimeUnit>* CanonicalDurationOrNull() override;
   AbstractCanonical<double>* CanonicalVolume() {
@@ -1039,6 +1039,9 @@ public:
   AbstractCanonical<int64_t>* CanonicalDecoderPosition() {
     return &mDecoderPosition;
   }
+  AbstractCanonical<bool>* CanonicalMediaSeekable() {
+    return &mMediaSeekable;
+  }
 };
 
 } // namespace mozilla

dom/media/MediaDecoderStateMachine.cpp

@@ -249,6 +249,8 @@ MediaDecoderStateMachine::MediaDecoderStateMachine(MediaDecoder* aDecoder,
                         "MediaDecoderStateMachine::mPlaybackRateReliable (Mirror)"),
   mDecoderPosition(mTaskQueue, 0,
                    "MediaDecoderStateMachine::mDecoderPosition (Mirror)"),
+  mMediaSeekable(mTaskQueue, true,
+                 "MediaDecoderStateMachine::mMediaSeekable (Mirror)"),
   mDuration(mTaskQueue, NullableTimeUnit(),
             "MediaDecoderStateMachine::mDuration (Canonical"),
   mIsShutdown(mTaskQueue, false,
@@ -334,6 +336,7 @@ MediaDecoderStateMachine::InitializationTask()
   mPlaybackBytesPerSecond.Connect(mDecoder->CanonicalPlaybackBytesPerSecond());
   mPlaybackRateReliable.Connect(mDecoder->CanonicalPlaybackRateReliable());
   mDecoderPosition.Connect(mDecoder->CanonicalDecoderPosition());
+  mMediaSeekable.Connect(mDecoder->CanonicalMediaSeekable());
 
   // Initialize watchers.
   mWatchManager.Watch(mBuffered, &MediaDecoderStateMachine::BufferedRangeUpdated);
@@ -1483,7 +1486,7 @@ MediaDecoderStateMachine::Seek(SeekTarget aTarget)
 
   // We need to be able to seek both at a transport level and at a media level
   // to seek.
-  if (!mDecoder->IsMediaSeekable()) {
+  if (!mMediaSeekable) {
     DECODER_WARN("Seek() function should not be called on a non-seekable state machine");
     return MediaDecoder::SeekPromise::CreateAndReject(/* aIgnored = */ true, __func__);
   }
@@ -2067,7 +2070,7 @@ MediaDecoderStateMachine::FinishDecodeFirstFrame()
 
   DECODER_LOG("Media duration %lld, "
               "transportSeekable=%d, mediaSeekable=%d",
-              Duration().ToMicroseconds(), mResource->IsTransportSeekable(), mDecoder->IsMediaSeekable());
+              Duration().ToMicroseconds(), mResource->IsTransportSeekable(), mMediaSeekable.Ref());
 
   if (HasAudio() && !HasVideo() && !mSentFirstFrameLoadedEvent) {
     // We're playing audio only. We don't need to worry about slow video
@@ -2236,6 +2239,7 @@ MediaDecoderStateMachine::FinishShutdown()
   mPlaybackBytesPerSecond.DisconnectIfConnected();
   mPlaybackRateReliable.DisconnectIfConnected();
   mDecoderPosition.DisconnectIfConnected();
+  mMediaSeekable.DisconnectIfConnected();
 
   mDuration.DisconnectAll();
   mIsShutdown.DisconnectAll();

dom/media/MediaDecoderStateMachine.h

@@ -1299,6 +1299,9 @@ private:
   // Current decoding position in the stream.
   Mirror<int64_t> mDecoderPosition;
 
+  // True if the media is seekable (i.e. supports random access).
+  Mirror<bool> mMediaSeekable;
+
   // Duration of the media. This is guaranteed to be non-null after we finish
   // decoding the first frame.
   Canonical<media::NullableTimeUnit> mDuration;