Fail on HLS+TS loss of sync

Issue:#3632

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=182202289

RELEASENOTES.md

@@ -41,13 +41,15 @@
   * Support in-band Emsg events targeting player with scheme id
     "urn:mpeg:dash:event:2012" and scheme value of either "1", "2" or "3".
   * Support DASH manifest EventStream elements.
-* HLS: Add opt-in support for chunkless preparation in HLS. This allows an
-  HLS source to finish preparation without downloading any chunks, which can
-  significantly reduce initial buffering time
-  ([#3149](https://github.com/google/ExoPlayer/issues/3149)).
 * DefaultTrackSelector:
   * Replace `DefaultTrackSelector.Parameters` copy methods with a builder.
   * Support disabling of individual text track selection flags.
+* HLS:
+    * Add opt-in support for chunkless preparation in HLS. This allows an
+      HLS source to finish preparation without downloading any chunks, which can
+      significantly reduce initial buffering time
+      ([#3149](https://github.com/google/ExoPlayer/issues/3149)).
+    * Fail on loss of sync with Transport Stream.
 * New Cast extension: Simplifies toggling between local and Cast playbacks.
 * Audio: Support TrueHD passthrough for rechunked samples in Matroska files
   ([#2147](https://github.com/google/ExoPlayer/issues/2147)).

library/core/src/main/java/com/google/android/exoplayer2/extractor/ts/TsExtractor.java

@@ -20,6 +20,7 @@ import android.util.SparseArray;
 import android.util.SparseBooleanArray;
 import android.util.SparseIntArray;
 import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.ParserException;
 import com.google.android.exoplayer2.extractor.Extractor;
 import com.google.android.exoplayer2.extractor.ExtractorInput;
 import com.google.android.exoplayer2.extractor.ExtractorOutput;
@@ -122,6 +123,7 @@ public final class TsExtractor implements Extractor {
   private int remainingPmts;
   private boolean tracksEnded;
   private TsPayloadReader id3Reader;
+  private int bytesSinceLastSync;
 
   public TsExtractor() {
     this(0);
@@ -163,7 +165,7 @@ public final class TsExtractor implements Extractor {
       timestampAdjusters = new ArrayList<>();
       timestampAdjusters.add(timestampAdjuster);
     }
-    tsPacketBuffer = new ParsableByteArray(BUFFER_SIZE);
+    tsPacketBuffer = new ParsableByteArray(new byte[BUFFER_SIZE], 0);
     trackIds = new SparseBooleanArray();
     tsPayloadReaders = new SparseArray<>();
     continuityCounters = new SparseIntArray();
@@ -206,6 +208,7 @@ public final class TsExtractor implements Extractor {
     continuityCounters.clear();
     // Elementary stream readers' state should be cleared to get consistent behaviours when seeking.
     resetPayloadReaders();
+    bytesSinceLastSync = 0;
   }
 
   @Override
@@ -238,8 +241,9 @@ public final class TsExtractor implements Extractor {
     }
 
     // Note: See ISO/IEC 13818-1, section 2.4.3.2 for details of the header format.
-    final int limit = tsPacketBuffer.limit();
+    int limit = tsPacketBuffer.limit();
     int position = tsPacketBuffer.getPosition();
+    int searchStart = position;
     while (position < limit && data[position] != TS_SYNC_BYTE) {
       position++;
     }
@@ -247,8 +251,13 @@ public final class TsExtractor implements Extractor {
 
     int endOfPacket = position + TS_PACKET_SIZE;
     if (endOfPacket > limit) {
+      bytesSinceLastSync += position - searchStart;
+      if (mode == MODE_HLS && bytesSinceLastSync > TS_PACKET_SIZE * 2) {
+        throw new ParserException("Cannot find sync byte. Most likely not a Transport Stream.");
+      }
       return RESULT_CONTINUE;
     }
+    bytesSinceLastSync = 0;
 
     int tsPacketHeader = tsPacketBuffer.readInt();
     if ((tsPacketHeader & 0x800000) != 0) { // transport_error_indicator

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

@@ -20,6 +20,7 @@ import android.util.Log;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.FormatHolder;
+import com.google.android.exoplayer2.ParserException;
 import com.google.android.exoplayer2.decoder.DecoderInputBuffer;
 import com.google.android.exoplayer2.extractor.DummyTrackOutput;
 import com.google.android.exoplayer2.extractor.ExtractorOutput;
@@ -610,7 +611,7 @@ import java.util.Arrays;
       }
       return Loader.DONT_RETRY;
     } else {
-      return Loader.RETRY;
+      return error instanceof ParserException ? Loader.DONT_RETRY_FATAL : Loader.RETRY;
     }
   }