Bug 1405025. P1 - ensure 'seeking' is fired before 'waiting'. r=jya

Use MediaEventSource instead of state-mirroring to notify nextFrameStatus
changes so we have more control over the order of events.

MozReview-Commit-ID: 3DGtMbghEQm

--HG--
extra : rebase_source : 774fc3da290c033769871a1bd7230177ff24d5bf
extra : intermediate-source : 6583b9281492be1a3bb0771b600cd80efd487af8
extra : source : 00570c319bfbd94970d4c637c7bf81b52d79ca02

dom/media/MediaDecoder.cpp

@@ -374,7 +374,6 @@ MediaDecoder::MediaDecoder(MediaDecoderInit& aInit)
   , mHasSuspendTaint(aInit.mHasSuspendTaint)
   , mPlaybackRate(aInit.mPlaybackRate)
   , INIT_MIRROR(mBuffered, TimeIntervals())
-  , INIT_MIRROR(mNextFrameStatus, MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE)
   , INIT_MIRROR(mCurrentPosition, TimeUnit::Zero())
   , INIT_MIRROR(mStateMachineDuration, NullableTimeUnit())
   , INIT_MIRROR(mPlaybackPosition, 0)
@@ -404,7 +403,6 @@ MediaDecoder::MediaDecoder(MediaDecoderInit& aInit)
 
   // readyState
   mWatchManager.Watch(mPlayState, &MediaDecoder::UpdateReadyState);
-  mWatchManager.Watch(mNextFrameStatus, &MediaDecoder::UpdateReadyState);
   // ReadyState computation depends on MediaDecoder::CanPlayThrough, which
   // depends on the download rate.
   mWatchManager.Watch(mBuffered, &MediaDecoder::UpdateReadyState);
@@ -452,6 +450,7 @@ MediaDecoder::Shutdown()
     mOnEncrypted.Disconnect();
     mOnWaitingForKey.Disconnect();
     mOnDecodeWarning.Disconnect();
+    mOnNextFrameStatus.Disconnect();
 
     mDecoderStateMachine->BeginShutdown()
       ->Then(mAbstractMainThread, __func__, this,
@@ -557,6 +556,36 @@ MediaDecoder::OnDecoderDoctorEvent(DecoderDoctorEvent aEvent)
   diags.StoreEvent(doc, aEvent, __func__);
 }
 
+static const char*
+NextFrameStatusToStr(MediaDecoderOwner::NextFrameStatus aStatus)
+{
+  switch (aStatus) {
+    case MediaDecoderOwner::NEXT_FRAME_AVAILABLE:
+      return "NEXT_FRAME_AVAILABLE";
+    case MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE:
+      return "NEXT_FRAME_UNAVAILABLE";
+    case MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_BUFFERING:
+      return "NEXT_FRAME_UNAVAILABLE_BUFFERING";
+    case MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_SEEKING:
+      return "NEXT_FRAME_UNAVAILABLE_SEEKING";
+    case MediaDecoderOwner::NEXT_FRAME_UNINITIALIZED:
+      return "NEXT_FRAME_UNINITIALIZED";
+  }
+  return "UNKNOWN";
+}
+
+void
+MediaDecoder::OnNextFrameStatus(MediaDecoderOwner::NextFrameStatus aStatus)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_DIAGNOSTIC_ASSERT(!IsShutdown());
+  if (mNextFrameStatus != aStatus) {
+    LOG("Changed mNextFrameStatus to %s", NextFrameStatusToStr(aStatus));
+    mNextFrameStatus = aStatus;
+    UpdateReadyState();
+  }
+}
+
 void
 MediaDecoder::FinishShutdown()
 {
@@ -606,6 +635,8 @@ MediaDecoder::SetStateMachineParameters()
     mAbstractMainThread, this, &MediaDecoder::OnDecoderDoctorEvent);
   mOnMediaNotSeekable = mDecoderStateMachine->OnMediaNotSeekable().Connect(
     mAbstractMainThread, this, &MediaDecoder::OnMediaNotSeekable);
+  mOnNextFrameStatus = mDecoderStateMachine->OnNextFrameStatus().Connect(
+    mAbstractMainThread, this, &MediaDecoder::OnNextFrameStatus);
 
   mOnEncrypted = mReader->OnEncrypted().Connect(
     mAbstractMainThread, GetOwner(), &MediaDecoderOwner::DispatchEncrypted);
@@ -1247,7 +1278,6 @@ MediaDecoder::ConnectMirrors(MediaDecoderStateMachine* aObject)
   MOZ_ASSERT(aObject);
   mStateMachineDuration.Connect(aObject->CanonicalDuration());
   mBuffered.Connect(aObject->CanonicalBuffered());
-  mNextFrameStatus.Connect(aObject->CanonicalNextFrameStatus());
   mCurrentPosition.Connect(aObject->CanonicalCurrentPosition());
   mPlaybackPosition.Connect(aObject->CanonicalPlaybackOffset());
   mIsAudioDataAudible.Connect(aObject->CanonicalIsAudioDataAudible());
@@ -1259,7 +1289,6 @@ MediaDecoder::DisconnectMirrors()
   MOZ_ASSERT(NS_IsMainThread());
   mStateMachineDuration.DisconnectIfConnected();
   mBuffered.DisconnectIfConnected();
-  mNextFrameStatus.DisconnectIfConnected();
   mCurrentPosition.DisconnectIfConnected();
   mPlaybackPosition.DisconnectIfConnected();
   mIsAudioDataAudible.DisconnectIfConnected();

dom/media/MediaDecoder.h

@@ -494,6 +494,8 @@ private:
     mMediaSeekable = false;
   }
 
+  void OnNextFrameStatus(MediaDecoderOwner::NextFrameStatus);
+
   void FinishShutdown();
 
   void ConnectMirrors(MediaDecoderStateMachine* aObject);
@@ -579,6 +581,9 @@ protected:
   // disabled.
   bool mHasSuspendTaint;
 
+  MediaDecoderOwner::NextFrameStatus mNextFrameStatus =
+    MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE;
+
   // A listener to receive metadata updates from MDSM.
   MediaEventListener mTimedMetadataListener;
 
@@ -592,6 +597,7 @@ protected:
   MediaEventListener mOnEncrypted;
   MediaEventListener mOnWaitingForKey;
   MediaEventListener mOnDecodeWarning;
+  MediaEventListener mOnNextFrameStatus;
 
 protected:
   // PlaybackRate and pitch preservation status we should start at.
@@ -600,9 +606,6 @@ protected:
   // Buffered range, mirrored from the reader.
   Mirror<media::TimeIntervals> mBuffered;
 
-  // NextFrameStatus, mirrored from the state machine.
-  Mirror<MediaDecoderOwner::NextFrameStatus> mNextFrameStatus;
-
   // NB: Don't use mCurrentPosition directly, but rather CurrentPosition().
   Mirror<media::TimeUnit> mCurrentPosition;
 

dom/media/MediaDecoderStateMachine.cpp

@@ -869,7 +869,7 @@ public:
       mMaster->StopPlayback();
       mMaster->UpdatePlaybackPositionInternal(mSeekJob.mTarget->GetTime());
       mMaster->mOnPlaybackEvent.Notify(MediaEventType::SeekStarted);
-      mMaster->UpdateNextFrameStatus(
+      mMaster->mOnNextFrameStatus.Notify(
         MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_SEEKING);
     }
 
@@ -1144,8 +1144,9 @@ protected:
       MOZ_ASSERT_IF(aReject.mType == MediaData::VIDEO_DATA, !mMaster->IsWaitingVideoData());
 
       // Fire 'waiting' to notify the player that we are waiting for data.
-      mMaster->UpdateNextFrameStatus(
+      mMaster->mOnNextFrameStatus.Notify(
         MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_SEEKING);
+
       Reader()
         ->WaitForData(aReject.mType)
         ->Then(OwnerThread(), __func__,
@@ -1795,7 +1796,7 @@ public:
 
     mBufferingStart = TimeStamp::Now();
     mMaster->ScheduleStateMachineIn(TimeUnit::FromMicroseconds(USECS_PER_S));
-    mMaster->UpdateNextFrameStatus(
+    mMaster->mOnNextFrameStatus.Notify(
       MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_BUFFERING);
   }
 
@@ -1901,7 +1902,7 @@ public:
     bool hasNextFrame = (!mMaster->HasAudio() || !mMaster->mAudioCompleted) &&
                         (!mMaster->HasVideo() || !mMaster->mVideoCompleted);
 
-    mMaster->UpdateNextFrameStatus(
+    mMaster->mOnNextFrameStatus.Notify(
       hasNextFrame ? MediaDecoderOwner::NEXT_FRAME_AVAILABLE
                    : MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE);
 
@@ -2281,7 +2282,7 @@ DecodingState::Enter()
     }
   });
 
-  mMaster->UpdateNextFrameStatus(MediaDecoderOwner::NEXT_FRAME_AVAILABLE);
+  mMaster->mOnNextFrameStatus.Notify(MediaDecoderOwner::NEXT_FRAME_AVAILABLE);
 
   mDecodeStartTime = TimeStamp::Now();
 
@@ -2573,7 +2574,6 @@ ShutdownState::Enter()
   master->mMediaPrincipalHandle.DisconnectIfConnected();
 
   master->mDuration.DisconnectAll();
-  master->mNextFrameStatus.DisconnectAll();
   master->mCurrentPosition.DisconnectAll();
   master->mPlaybackOffset.DisconnectAll();
   master->mIsAudioDataAudible.DisconnectAll();
@@ -2626,7 +2626,6 @@ MediaDecoderStateMachine::MediaDecoderStateMachine(MediaDecoder* aDecoder,
   INIT_MIRROR(mSameOriginMedia, false),
   INIT_MIRROR(mMediaPrincipalHandle, PRINCIPAL_HANDLE_NONE),
   INIT_CANONICAL(mDuration, NullableTimeUnit()),
-  INIT_CANONICAL(mNextFrameStatus, MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE),
   INIT_CANONICAL(mCurrentPosition, TimeUnit::Zero()),
   INIT_CANONICAL(mPlaybackOffset, 0),
   INIT_CANONICAL(mIsAudioDataAudible, false)
@@ -3487,34 +3486,6 @@ MediaDecoderStateMachine::UpdatePlaybackPositionPeriodically()
   ScheduleStateMachineIn(TimeUnit::FromMicroseconds(delay));
 }
 
-/* static */ const char*
-MediaDecoderStateMachine::ToStr(NextFrameStatus aStatus)
-{
-  switch (aStatus) {
-    case MediaDecoderOwner::NEXT_FRAME_AVAILABLE:
-      return "NEXT_FRAME_AVAILABLE";
-    case MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE:
-      return "NEXT_FRAME_UNAVAILABLE";
-    case MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_BUFFERING:
-      return "NEXT_FRAME_UNAVAILABLE_BUFFERING";
-    case MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_SEEKING:
-      return "NEXT_FRAME_UNAVAILABLE_SEEKING";
-    case MediaDecoderOwner::NEXT_FRAME_UNINITIALIZED:
-      return "NEXT_FRAME_UNINITIALIZED";
-  }
-  return "UNKNOWN";
-}
-
-void
-MediaDecoderStateMachine::UpdateNextFrameStatus(NextFrameStatus aStatus)
-{
-  MOZ_ASSERT(OnTaskQueue());
-  if (aStatus != mNextFrameStatus) {
-    LOG("Changed mNextFrameStatus to %s", ToStr(aStatus));
-    mNextFrameStatus = aStatus;
-  }
-}
-
 void
 MediaDecoderStateMachine::ScheduleStateMachine()
 {

dom/media/MediaDecoderStateMachine.h

@@ -252,6 +252,9 @@ public:
   MediaEventSource<DecoderDoctorEvent>&
   OnDecoderDoctorEvent() { return mOnDecoderDoctorEvent; }
 
+  MediaEventSource<NextFrameStatus>&
+  OnNextFrameStatus() { return mOnNextFrameStatus; }
+
   size_t SizeOfVideoQueue() const;
 
   size_t SizeOfAudioQueue() const;
@@ -275,7 +278,6 @@ private:
   class ShutdownState;
 
   static const char* ToStateStr(State aState);
-  static const char* ToStr(NextFrameStatus aStatus);
   const char* ToStateStr();
 
   nsCString GetDebugInfo();
@@ -383,8 +385,6 @@ protected:
   // Returns true if we have less than aThreshold of buffered data available.
   bool HasLowBufferedData(const media::TimeUnit& aThreshold);
 
-  void UpdateNextFrameStatus(NextFrameStatus aStatus);
-
   // Return the current time, either the audio clock if available (if the media
   // has audio, and the playback is possible), or a clock for the video.
   // Called on the state machine thread.
@@ -661,6 +661,8 @@ private:
 
   MediaEventProducer<DecoderDoctorEvent> mOnDecoderDoctorEvent;
 
+  MediaEventProducer<NextFrameStatus> mOnNextFrameStatus;
+
   const bool mIsMSE;
 
 private:
@@ -692,10 +694,6 @@ private:
   // decoding the first frame.
   Canonical<media::NullableTimeUnit> mDuration;
 
-  // The status of our next frame. Mirrored on the main thread and used to
-  // compute ready state.
-  Canonical<NextFrameStatus> mNextFrameStatus;
-
   // The time of the current frame, corresponding to the "current
   // playback position" in HTML5. This is referenced from 0, which is the initial
   // playback position.
@@ -714,10 +712,6 @@ public:
   {
     return &mDuration;
   }
-  AbstractCanonical<NextFrameStatus>* CanonicalNextFrameStatus()
-  {
-    return &mNextFrameStatus;
-  }
   AbstractCanonical<media::TimeUnit>* CanonicalCurrentPosition()
   {
     return &mCurrentPosition;