In continueBuffering, return whether a particular track has samples.

Issue: #595

extensions/opus/src/main/java/com/google/android/exoplayer/ext/opus/LibopusAudioTrackRenderer.java

@@ -153,7 +153,7 @@ public class LibopusAudioTrackRenderer extends TrackRenderer implements MediaClo
       return;
     }
     try {
-      sourceIsReady = source.continueBuffering(positionUs);
+      sourceIsReady = source.continueBuffering(trackIndex, positionUs);
       checkForDiscontinuity();
       if (format == null) {
         readFormat();

extensions/vp9/src/main/java/com/google/android/exoplayer/ext/vp9/LibvpxVideoTrackRenderer.java

@@ -179,7 +179,7 @@ public class LibvpxVideoTrackRenderer extends TrackRenderer {
       return;
     }
     try {
-      sourceIsReady = source.continueBuffering(positionUs);
+      sourceIsReady = source.continueBuffering(trackIndex, positionUs);
       checkForDiscontinuity(positionUs);
       if (format == null) {
         readFormat(positionUs);

library/src/main/java/com/google/android/exoplayer/FrameworkSampleSource.java

@@ -174,7 +174,7 @@ public final class FrameworkSampleSource implements SampleSource, SampleSourceRe
   }
 
   @Override
-  public boolean continueBuffering(long positionUs) {
+  public boolean continueBuffering(int track, long positionUs) {
     // MediaExtractor takes care of buffering and blocks until it has samples, so we can always
     // return true here. Although note that the blocking behavior is itself as bug, as per the
     // TODO further up this file. This method will need to return something else as part of fixing

library/src/main/java/com/google/android/exoplayer/MediaCodecTrackRenderer.java

@@ -490,7 +490,7 @@ public abstract class MediaCodecTrackRenderer extends TrackRenderer {
   @Override
   protected void doSomeWork(long positionUs, long elapsedRealtimeUs) throws ExoPlaybackException {
     try {
-      sourceState = source.continueBuffering(positionUs)
+      sourceState = source.continueBuffering(trackIndex, positionUs)
           ? (sourceState == SOURCE_STATE_NOT_READY ? SOURCE_STATE_READY : sourceState)
           : SOURCE_STATE_NOT_READY;
       checkForDiscontinuity(positionUs);

library/src/main/java/com/google/android/exoplayer/SampleSource.java

@@ -117,14 +117,15 @@ public interface SampleSource {
     public void disable(int track);
 
     /**
-     * Indicates to the source that it should still be buffering data.
+     * Indicates to the source that it should still be buffering data for the specified track.
      *
+     * @param track The track to continue buffering.
      * @param positionUs The current playback position.
-     * @return True if the source has available samples, or if the end of the stream has been
+     * @return True if the track has available samples, or if the end of the stream has been
      *     reached. False if more data needs to be buffered for samples to become available.
      * @throws IOException If an error occurred reading from the source.
      */
-    public boolean continueBuffering(long positionUs) throws IOException;
+    public boolean continueBuffering(int track, long positionUs) throws IOException;
 
     /**
      * Attempts to read either a sample, a new format or or a discontinuity from the source.

library/src/main/java/com/google/android/exoplayer/chunk/ChunkSampleSource.java

@@ -188,8 +188,9 @@ public class ChunkSampleSource implements SampleSource, SampleSourceReader, Load
   }
 
   @Override
-  public boolean continueBuffering(long positionUs) throws IOException {
+  public boolean continueBuffering(int track, long positionUs) throws IOException {
     Assertions.checkState(state == STATE_ENABLED);
+    Assertions.checkState(track == 0);
     downstreamPositionUs = positionUs;
     chunkSource.continueBuffering(positionUs);
     updateLoadControl();

library/src/main/java/com/google/android/exoplayer/extractor/ExtractorSampleSource.java

@@ -180,7 +180,7 @@ public class ExtractorSampleSource implements SampleSource, SampleSourceReader,
       loader = new Loader("Loader:ExtractorSampleSource");
     }
 
-    continueBufferingInternal();
+    maybeStartLoading();
 
     if (seekMap != null && tracksBuilt && haveFormatsForAllTracks()) {
       int trackCount = sampleQueues.size();
@@ -246,12 +246,23 @@ public class ExtractorSampleSource implements SampleSource, SampleSourceReader,
   }
 
   @Override
-  public boolean continueBuffering(long playbackPositionUs) throws IOException {
+  public boolean continueBuffering(int track, long playbackPositionUs) throws IOException {
     Assertions.checkState(prepared);
-    Assertions.checkState(enabledTrackCount > 0);
+    Assertions.checkState(trackEnabledStates[track]);
     downstreamPositionUs = playbackPositionUs;
     discardSamplesForDisabledTracks(downstreamPositionUs);
-    return loadingFinished || continueBufferingInternal();
+    if (loadingFinished) {
+      return true;
+    }
+    maybeStartLoading();
+    if (isPendingReset()) {
+      return false;
+    }
+    if (sampleQueues.valueAt(track).isEmpty()) {
+      maybeThrowLoadableException();
+      return false;
+    }
+    return true;
   }
 
   @Override
@@ -411,18 +422,6 @@ public class ExtractorSampleSource implements SampleSource, SampleSourceReader,
 
   // Internal stuff.
 
-  private boolean continueBufferingInternal() throws IOException {
-    maybeStartLoading();
-    if (isPendingReset()) {
-      return false;
-    }
-    boolean haveSamples = prepared && haveSampleForOneEnabledTrack();
-    if (!haveSamples) {
-      maybeThrowLoadableException();
-    }
-    return haveSamples;
-  }
-
   private void restartFrom(long positionUs) {
     pendingResetPositionUs = positionUs;
     loadingFinished = false;
@@ -532,15 +531,6 @@ public class ExtractorSampleSource implements SampleSource, SampleSourceReader,
     return true;
   }
 
-  private boolean haveSampleForOneEnabledTrack() {
-    for (int i = 0; i < trackEnabledStates.length; i++) {
-      if (trackEnabledStates[i] && !sampleQueues.valueAt(i).isEmpty()) {
-        return true;
-      }
-    }
-    return false;
-  }
-
   private void discardSamplesForDisabledTracks(long timeUs) {
     for (int i = 0; i < trackEnabledStates.length; i++) {
       if (!trackEnabledStates[i]) {

library/src/main/java/com/google/android/exoplayer/hls/HlsSampleSource.java

@@ -218,26 +218,32 @@ public class HlsSampleSource implements SampleSource, SampleSourceReader, Loader
   }
 
   @Override
-  public boolean continueBuffering(long playbackPositionUs) throws IOException {
+  public boolean continueBuffering(int track, long playbackPositionUs) throws IOException {
     Assertions.checkState(prepared);
-    Assertions.checkState(enabledTrackCount > 0);
+    Assertions.checkState(trackEnabledStates[track]);
     downstreamPositionUs = playbackPositionUs;
     if (!extractors.isEmpty()) {
       discardSamplesForDisabledTracks(getCurrentExtractor(), downstreamPositionUs);
     }
-    return loadingFinished || continueBufferingInternal();
-  }
-
-  private boolean continueBufferingInternal() throws IOException {
+    if (loadingFinished) {
+      return true;
+    }
     maybeStartLoading();
     if (isPendingReset() || extractors.isEmpty()) {
       return false;
     }
-    boolean haveSamples = prepared && haveSamplesForEnabledTracks(getCurrentExtractor());
-    if (!haveSamples) {
-      maybeThrowLoadableException();
+
+    for (int extractorIndex = 0; extractorIndex < extractors.size(); extractorIndex++) {
+      HlsExtractorWrapper extractor = extractors.get(extractorIndex);
+      if (!extractor.isPrepared()) {
+        break;
+      }
+      if (extractor.hasSamples(track)) {
+        return true;
+      }
     }
-    return haveSamples;
+    maybeThrowLoadableException();
+    return false;
   }
 
   @Override

library/src/main/java/com/google/android/exoplayer/metadata/MetadataTrackRenderer.java

@@ -129,7 +129,7 @@ public class MetadataTrackRenderer<T> extends TrackRenderer implements Callback
   protected void doSomeWork(long positionUs, long elapsedRealtimeUs)
       throws ExoPlaybackException {
     try {
-      source.continueBuffering(positionUs);
+      source.continueBuffering(trackIndex, positionUs);
     } catch (IOException e) {
       throw new ExoPlaybackException(e);
     }

library/src/main/java/com/google/android/exoplayer/text/TextTrackRenderer.java

@@ -129,7 +129,7 @@ public class TextTrackRenderer extends TrackRenderer implements Callback {
   @Override
   protected void doSomeWork(long positionUs, long elapsedRealtimeUs) throws ExoPlaybackException {
     try {
-      source.continueBuffering(positionUs);
+      source.continueBuffering(trackIndex, positionUs);
     } catch (IOException e) {
       throw new ExoPlaybackException(e);
     }

library/src/main/java/com/google/android/exoplayer/text/eia608/Eia608TrackRenderer.java

@@ -134,7 +134,7 @@ public class Eia608TrackRenderer extends TrackRenderer implements Callback {
   @Override
   protected void doSomeWork(long positionUs, long elapsedRealtimeUs) throws ExoPlaybackException {
     try {
-      source.continueBuffering(positionUs);
+      source.continueBuffering(trackIndex, positionUs);
     } catch (IOException e) {
       throw new ExoPlaybackException(e);
     }