Fix NPE when reading from a SampleQueue from a loading thread

Issue: #7273
PiperOrigin-RevId: 308238035

RELEASENOTES.md

-<<<<<<< HEAD
 # Release notes #
 
 ### Next release ###
@@ -14,6 +13,8 @@
         `http://dashif.org/guidelines/trickmode`) into the same `TrackGroup` as
         the main adaptation sets to which they refer. Trick play tracks are
         marked with the `C.ROLE_FLAG_TRICK_PLAY` flag.
+    *   Fix assertion failure in `SampleQueue` when playing DASH streams with
+        EMSG tracks ([#7273](https://github.com/google/ExoPlayer/issues/7273)).
 *   MPEG-TS: Fix issue where SEI NAL units were incorrectly dropped from H.265
     samples ([#7113](https://github.com/google/ExoPlayer/issues/7113)).
 * Text

library/core/src/main/java/com/google/android/exoplayer2/source/ProgressiveMediaPeriod.java

@@ -679,7 +679,8 @@ import org.checkerframework.checker.nullness.compatqual.NullableType;
         return sampleQueues[i];
       }
     }
-    SampleQueue trackOutput = new SampleQueue(allocator, drmSessionManager);
+    SampleQueue trackOutput = new SampleQueue(
+        allocator, /* playbackLooper= */ handler.getLooper(), drmSessionManager);
     trackOutput.setUpstreamFormatChangeListener(this);
     @NullableType
     TrackId[] sampleQueueTrackIds = Arrays.copyOf(this.sampleQueueTrackIds, trackCount + 1);

library/core/src/main/java/com/google/android/exoplayer2/source/SampleQueue.java

@@ -55,6 +55,7 @@ public class SampleQueue implements TrackOutput {
   private final SampleExtrasHolder extrasHolder;
   private final DrmSessionManager<?> drmSessionManager;
   private UpstreamFormatChangedListener upstreamFormatChangeListener;
+  private final Looper playbackLooper;
 
   @Nullable private Format downstreamFormat;
   @Nullable private DrmSession<?> currentDrmSession;
@@ -91,11 +92,13 @@ public class SampleQueue implements TrackOutput {
    * Creates a sample queue.
    *
    * @param allocator An {@link Allocator} from which allocations for sample data can be obtained.
+   * @param playbackLooper The looper associated with the media playback thread.
    * @param drmSessionManager The {@link DrmSessionManager} to obtain {@link DrmSession DrmSessions}
    *     from. The created instance does not take ownership of this {@link DrmSessionManager}.
    */
-  public SampleQueue(Allocator allocator, DrmSessionManager<?> drmSessionManager) {
+  public SampleQueue(Allocator allocator, Looper playbackLooper, DrmSessionManager<?> drmSessionManager) {
     sampleDataQueue = new SampleDataQueue(allocator);
+    this.playbackLooper = playbackLooper;
     this.drmSessionManager = drmSessionManager;
     extrasHolder = new SampleExtrasHolder();
     capacity = SAMPLE_CAPACITY_INCREMENT;
@@ -789,8 +792,7 @@ public class SampleQueue implements TrackOutput {
     }
     // Ensure we acquire the new session before releasing the previous one in case the same session
     // is being used for both DrmInitData.
-    DrmSession<?> previousSession = currentDrmSession;
-    Looper playbackLooper = Assertions.checkNotNull(Looper.myLooper());
+    @Nullable DrmSession previousSession = currentDrmSession;
     currentDrmSession =
         newDrmInitData != null
             ? drmSessionManager.acquireSession(playbackLooper, newDrmInitData)

library/core/src/main/java/com/google/android/exoplayer2/source/chunk/ChunkSampleStream.java

@@ -15,6 +15,7 @@
  */
 package com.google.android.exoplayer2.source.chunk;
 
+import android.os.Looper;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
@@ -130,13 +131,19 @@ public class ChunkSampleStream<T extends ChunkSource> implements SampleStream, S
     int[] trackTypes = new int[1 + embeddedTrackCount];
     SampleQueue[] sampleQueues = new SampleQueue[1 + embeddedTrackCount];
 
-    primarySampleQueue = new SampleQueue(allocator, drmSessionManager);
+    primarySampleQueue = new SampleQueue(
+        allocator,
+        /* playbackLooper= */ Assertions.checkNotNull(Looper.myLooper()),
+        drmSessionManager);
     trackTypes[0] = primaryTrackType;
     sampleQueues[0] = primarySampleQueue;
 
     for (int i = 0; i < embeddedTrackCount; i++) {
       SampleQueue sampleQueue =
-          new SampleQueue(allocator, DrmSessionManager.getDummyDrmSessionManager());
+          new SampleQueue(
+              allocator,
+              /* playbackLooper= */ Assertions.checkNotNull(Looper.myLooper()),
+              DrmSessionManager.getDummyDrmSessionManager());
       embeddedSampleQueues[i] = sampleQueue;
       sampleQueues[i + 1] = sampleQueue;
       trackTypes[i + 1] = embeddedTrackTypes[i];

library/core/src/test/java/com/google/android/exoplayer2/source/SampleQueueTest.java

@@ -26,6 +26,7 @@ import static java.util.Arrays.copyOfRange;
 import static org.junit.Assert.assertArrayEquals;
 import static org.mockito.Mockito.when;
 
+import android.os.Looper;
 import androidx.annotation.Nullable;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import com.google.android.exoplayer2.C;
@@ -40,6 +41,7 @@ import com.google.android.exoplayer2.extractor.TrackOutput;
 import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.upstream.Allocator;
 import com.google.android.exoplayer2.upstream.DefaultAllocator;
+import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.ParsableByteArray;
 import java.io.IOException;
 import java.util.Arrays;
@@ -143,7 +145,10 @@ public final class SampleQueueTest {
     mockDrmSession = (DrmSession<ExoMediaCrypto>) Mockito.mock(DrmSession.class);
     when(mockDrmSessionManager.acquireSession(ArgumentMatchers.any(), ArgumentMatchers.any()))
         .thenReturn(mockDrmSession);
-    sampleQueue = new SampleQueue(allocator, mockDrmSessionManager);
+    sampleQueue = new SampleQueue(
+        allocator,
+        /* playbackLooper= */ Assertions.checkNotNull(Looper.myLooper()),
+        mockDrmSessionManager);
     formatHolder = new FormatHolder();
     inputBuffer = new DecoderInputBuffer(DecoderInputBuffer.BUFFER_REPLACEMENT_MODE_NORMAL);
   }
@@ -360,7 +365,10 @@ public final class SampleQueueTest {
   public void testIsReadyReturnsTrueForClearSampleAndPlayClearSamplesWithoutKeysIsTrue() {
     when(mockDrmSession.playClearSamplesWithoutKeys()).thenReturn(true);
     // We recreate the queue to ensure the mock DRM session manager flags are taken into account.
-    sampleQueue = new SampleQueue(allocator, mockDrmSessionManager);
+    sampleQueue = new SampleQueue(
+        allocator,
+        /* playbackLooper= */ Assertions.checkNotNull(Looper.myLooper()),
+        mockDrmSessionManager);
     writeTestDataWithEncryptedSections();
     assertThat(sampleQueue.isReady(/* loadingFinished= */ false)).isTrue();
   }
@@ -542,7 +550,10 @@ public final class SampleQueueTest {
   public void testAllowPlayClearSamplesWithoutKeysReadsClearSamples() {
     when(mockDrmSession.playClearSamplesWithoutKeys()).thenReturn(true);
     // We recreate the queue to ensure the mock DRM session manager flags are taken into account.
-    sampleQueue = new SampleQueue(allocator, mockDrmSessionManager);
+    sampleQueue = new SampleQueue(
+        allocator,
+        /* playbackLooper= */ Assertions.checkNotNull(Looper.myLooper()),
+        mockDrmSessionManager);
     when(mockDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED);
     writeTestDataWithEncryptedSections();
 
@@ -931,7 +942,10 @@ public final class SampleQueueTest {
   public void testAdjustUpstreamFormat() {
     String label = "label";
     sampleQueue =
-        new SampleQueue(allocator, mockDrmSessionManager) {
+        new SampleQueue(
+            allocator,
+            /* playbackLooper= */ Assertions.checkNotNull(Looper.myLooper()),
+            mockDrmSessionManager) {
           @Override
           public Format getAdjustedUpstreamFormat(Format format) {
             return super.getAdjustedUpstreamFormat(format.copyWithLabel(label));
@@ -947,7 +961,10 @@ public final class SampleQueueTest {
   public void testInvalidateUpstreamFormatAdjustment() {
     AtomicReference<String> label = new AtomicReference<>("label1");
     sampleQueue =
-        new SampleQueue(allocator, mockDrmSessionManager) {
+        new SampleQueue(
+            allocator,
+            /* playbackLooper= */ Assertions.checkNotNull(Looper.myLooper()),
+            mockDrmSessionManager) {
           @Override
           public Format getAdjustedUpstreamFormat(Format format) {
             return super.getAdjustedUpstreamFormat(format.copyWithLabel(label.get()));

library/dash/src/main/java/com/google/android/exoplayer2/source/dash/PlayerEmsgHandler.java

@@ -284,7 +284,10 @@ public final class PlayerEmsgHandler implements Handler.Callback {
     private final MetadataInputBuffer buffer;
 
     /* package */ PlayerTrackEmsgHandler(Allocator allocator) {
-      this.sampleQueue = new SampleQueue(allocator, DrmSessionManager.getDummyDrmSessionManager());
+      this.sampleQueue = new SampleQueue(
+          allocator,
+          /* playbackLooper= */ handler.getLooper(),
+          DrmSessionManager.getDummyDrmSessionManager());
       formatHolder = new FormatHolder();
       buffer = new MetadataInputBuffer();
     }

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/HlsSampleStreamWrapper.java

@@ -17,6 +17,7 @@ package com.google.android.exoplayer2.source.hls;
 
 import android.net.Uri;
 import android.os.Handler;
+import android.os.Looper;
 import android.util.SparseIntArray;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
@@ -907,7 +908,11 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
 
     boolean isAudioVideo = type == C.TRACK_TYPE_AUDIO || type == C.TRACK_TYPE_VIDEO;
     FormatAdjustingSampleQueue trackOutput =
-        new FormatAdjustingSampleQueue(allocator, drmSessionManager, overridingDrmInitData);
+        new FormatAdjustingSampleQueue(
+            allocator,
+            /* playbackLooper= */ handler.getLooper(),
+            drmSessionManager,
+            overridingDrmInitData);
     if (isAudioVideo) {
       trackOutput.setDrmInitData(drmInitData);
     }
@@ -1331,9 +1336,10 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
 
     public FormatAdjustingSampleQueue(
         Allocator allocator,
+        Looper playbackLooper,
         DrmSessionManager<?> drmSessionManager,
         Map<String, DrmInitData> overridingDrmInitData) {
-      super(allocator, drmSessionManager);
+      super(allocator, playbackLooper, drmSessionManager);
       this.overridingDrmInitData = overridingDrmInitData;
     }