Bug 1002297 - Seek in unbuffered ranges with MSE - r=kinetik

content/html/content/src/HTMLMediaElement.cpp

@@ -3064,6 +3064,14 @@ void HTMLMediaElement::UpdateReadyStateForData(MediaDecoderOwner::NextFrameStatu
     return;
   }
 
+  // Section 2.4.3.1 of the Media Source Extensions spec requires
+  // changing to HAVE_METADATA when seeking into an unbuffered
+  // range.
+  if (aNextFrame == MediaDecoderOwner::NEXT_FRAME_WAIT_FOR_MSE_DATA) {
+    ChangeReadyState(nsIDOMHTMLMediaElement::HAVE_METADATA);
+    return;
+  }
+
   if (mReadyState > nsIDOMHTMLMediaElement::HAVE_METADATA &&
       mDownloadSuspendedByCache &&
       mDecoder &&

content/media/MediaDecoderOwner.h

@@ -119,6 +119,9 @@ public:
     NEXT_FRAME_UNAVAILABLE_BUFFERING,
     // The next frame of audio/video is unavailable for some other reasons
     NEXT_FRAME_UNAVAILABLE,
+    // The next frame is unavailable due to waiting for more Media Source
+    // Extensions data to become available.
+    NEXT_FRAME_WAIT_FOR_MSE_DATA,
     // Sentinel value
     NEXT_FRAME_UNINITIALIZED
   };

content/media/mediasource/MediaSource.cpp

@@ -299,6 +299,7 @@ MediaSource::MediaSource(nsPIDOMWindow* aWindow)
   , mDuration(UnspecifiedNaN<double>())
   , mDecoder(nullptr)
   , mReadyState(MediaSourceReadyState::Closed)
+  , mWaitForDataMonitor("MediaSource.WaitForData.Monitor")
 {
   mSourceBuffers = new SourceBufferList(this);
   mActiveSourceBuffers = new SourceBufferList(this);
@@ -395,6 +396,20 @@ MediaSource::NotifyEvicted(double aStart, double aEnd)
   mSourceBuffers->Evict(aStart, aEnd);
 }
 
+void
+MediaSource::WaitForData()
+{
+  MonitorAutoLock lock(mWaitForDataMonitor);
+  lock.Wait();
+}
+
+void
+MediaSource::NotifyGotData()
+{
+  MonitorAutoLock lock(mWaitForDataMonitor);
+  lock.NotifyAll();
+}
+
 NS_IMPL_CYCLE_COLLECTION_INHERITED(MediaSource, DOMEventTargetHelper,
                                    mSourceBuffers, mActiveSourceBuffers)
 

content/media/mediasource/MediaSource.h

@@ -13,6 +13,7 @@
 #include "mozilla/Attributes.h"
 #include "mozilla/DOMEventTargetHelper.h"
 #include "mozilla/dom/MediaSourceBinding.h"
+#include "mozilla/Monitor.h"
 #include "nsAutoPtr.h"
 #include "nsCOMPtr.h"
 #include "nsCycleCollectionNoteChild.h"
@@ -89,6 +90,12 @@ public:
   // that were evicted are provided.
   void NotifyEvicted(double aStart, double aEnd);
 
+  // Block thread waiting for data to be appended to a SourceBuffer.
+  void WaitForData();
+
+  // Unblock threads waiting for data to be appended to a SourceBuffer.
+  void NotifyGotData();
+
 private:
   explicit MediaSource(nsPIDOMWindow* aWindow);
 
@@ -106,6 +113,10 @@ private:
   nsRefPtr<MediaSourceDecoder> mDecoder;
 
   MediaSourceReadyState mReadyState;
+
+  // Monitor for waiting for when new data is appended to
+  // a Source Buffer.
+  Monitor mWaitForDataMonitor;
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(MediaSource, MOZILLA_DOM_MEDIASOURCE_IMPLEMENTATION_IID)

content/media/mediasource/MediaSourceDecoder.cpp

@@ -130,6 +130,11 @@ public:
 
   void InitializePendingDecoders();
 
+  bool IsShutdown() {
+    ReentrantMonitorAutoEnter decoderMon(mDecoder->GetReentrantMonitor());
+    return mDecoder->IsShutdown();
+  }
+
 private:
   bool MaybeSwitchVideoReaders(int64_t aTimeThreshold) {
     ReentrantMonitorAutoEnter mon(mDecoder->GetReentrantMonitor());
@@ -383,25 +388,60 @@ MediaSourceReader::CreateSubDecoder(const nsACString& aType, MediaSourceDecoder*
   return decoder.forget();
 }
 
+namespace {
+class ChangeToHaveMetadata : public nsRunnable {
+public:
+  ChangeToHaveMetadata(AbstractMediaDecoder* aDecoder) :
+    mDecoder(aDecoder)
+  {
+  }
+
+  NS_IMETHOD Run() MOZ_OVERRIDE MOZ_FINAL {
+    auto owner = mDecoder->GetOwner();
+    if (owner) {
+      owner->UpdateReadyStateForData(MediaDecoderOwner::NEXT_FRAME_WAIT_FOR_MSE_DATA);
+    }
+    return NS_OK;
+  }
+
+private:
+  nsRefPtr<AbstractMediaDecoder> mDecoder;
+};
+}
+
 nsresult
 MediaSourceReader::Seek(int64_t aTime, int64_t aStartTime, int64_t aEndTime,
                         int64_t aCurrentTime)
 {
-  ResetDecode();
+  if (!mMediaSource->ActiveSourceBuffers()->AllContainsTime (aTime / USECS_PER_S)) {
+    NS_DispatchToMainThread(new ChangeToHaveMetadata(mDecoder));
+  }
 
-  dom::SourceBufferList* sbl = mMediaSource->ActiveSourceBuffers();
-  if (sbl->AllContainsTime (aTime / USECS_PER_S)) {
-    if (GetAudioReader()) {
-      nsresult rv = GetAudioReader()->Seek(aTime, aStartTime, aEndTime, aCurrentTime);
-      if (NS_FAILED(rv)) {
-        return rv;
-      }
+  // Loop until we have the requested time range in the source buffers.
+  // This is a workaround for our lack of async functionality in the
+  // MediaDecoderStateMachine. Bug 979104 implements what we need and
+  // we'll remove this for an async approach based on that in bug XXXXXXX.
+  while (!mMediaSource->ActiveSourceBuffers()->AllContainsTime (aTime / USECS_PER_S)
+         && !IsShutdown()) {
+    mMediaSource->WaitForData();
+    MaybeSwitchVideoReaders(aTime);
+  }
+
+  if (IsShutdown()) {
+    return NS_OK;
+  }
+
+  ResetDecode();
+  if (GetAudioReader()) {
+    nsresult rv = GetAudioReader()->Seek(aTime, aStartTime, aEndTime, aCurrentTime);
+    if (NS_FAILED(rv)) {
+      return rv;
     }
-    if (GetVideoReader()) {
-      nsresult rv = GetVideoReader()->Seek(aTime, aStartTime, aEndTime, aCurrentTime);
-      if (NS_FAILED(rv)) {
-        return rv;
-      }
+  }
+  if (GetVideoReader()) {
+    nsresult rv = GetVideoReader()->Seek(aTime, aStartTime, aEndTime, aCurrentTime);
+     if (NS_FAILED(rv)) {
+      return rv;
     }
   }
   return NS_OK;

content/media/mediasource/SourceBuffer.cpp

@@ -493,6 +493,8 @@ SourceBuffer::AppendData(const uint8_t* aData, uint32_t aLength, ErrorResult& aR
   // Schedule the state machine thread to ensure playback starts
   // if required when data is appended.
   mMediaSource->GetDecoder()->ScheduleStateMachineThread();
+
+  mMediaSource->NotifyGotData();
 }
 
 void