From 245c9fec5a0ec42598dcc0113c325ae916bd323b Mon Sep 17 00:00:00 2001
From: Steve Mayhew <mayhew.steve@gmail.com>
Date: Fri, 15 Nov 2019 13:35:48 -0800
Subject: [PATCH] Cleanup tunneled onFrameRenderListener

Cleanup the handler to prevent stale messages and potential handler leaks
---
 .../video/MediaCodecVideoRenderer.java        | 48 ++++++++++++++++++-
 1 file changed, 46 insertions(+), 2 deletions(-)

diff --git a/library/core/src/main/java/com/google/android/exoplayer2/video/MediaCodecVideoRenderer.java b/library/core/src/main/java/com/google/android/exoplayer2/video/MediaCodecVideoRenderer.java
index 14f864b08a..68ebb3893d 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/video/MediaCodecVideoRenderer.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/video/MediaCodecVideoRenderer.java
@@ -563,6 +563,9 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
     clearReportedVideoSize();
     clearRenderedFirstFrame();
     frameReleaseTimeHelper.disable();
+    if (tunnelingOnFrameRenderedListener != null && getCodec() != null) {
+      tunnelingOnFrameRenderedListener.destroyHandler(getCodec());
+    }
     tunnelingOnFrameRenderedListener = null;
     try {
       super.onDisabled();
@@ -687,6 +690,9 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
     }
     codec.configure(mediaFormat, surface, crypto, 0);
     if (Util.SDK_INT >= 23 && tunneling) {
+      if (tunnelingOnFrameRenderedListener != null) {
+        tunnelingOnFrameRenderedListener.destroyHandler(codec);
+      }
       tunnelingOnFrameRenderedListener = new OnFrameRenderedListenerV23(codec);
     }
   }
@@ -1228,6 +1234,9 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
       MediaCodec codec = getCodec();
       // If codec is null then the listener will be instantiated in configureCodec.
       if (codec != null) {
+        if (tunnelingOnFrameRenderedListener != null) {
+          tunnelingOnFrameRenderedListener.destroyHandler(codec);
+        }
         tunnelingOnFrameRenderedListener = new OnFrameRenderedListenerV23(codec);
       }
     }
@@ -1808,8 +1817,23 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
   @TargetApi(23)
   private final class OnFrameRenderedListenerV23 implements MediaCodec.OnFrameRenderedListener {
 
+    private final Handler handler;
+
     private OnFrameRenderedListenerV23(MediaCodec codec) {
-      codec.setOnFrameRenderedListener(/* listener= */ this, Util.createHandler());
+      handler = new Handler();
+      codec.setOnFrameRenderedListener(/* listener= */ this, handler);
+    }
+
+    /**
+     * Cleanup any messages pending for this listener before removing references to it
+     *
+     * @param codec optional, if the codec is still around it should be passed here
+     */
+    void destroyHandler(@Nullable MediaCodec codec) {
+      if (codec != null) {
+        codec.setOnFrameRenderedListener(null, null);
+      }
+      handler.removeCallbacksAndMessages(null);
     }
 
     @Override
@@ -1818,12 +1842,32 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
         // Stale event.
         return;
       }
+
+      // Work around bug in MediaCodec that causes deadlocks if you call back a
+      // MediaCodec API that requires MediaCodec to use it's Looper, as it calls this
+      // listener method holding locks.  This was fixed in:
+      //  https://android-review.googlesource.com/1156807
+      //
+      // The work around simply queues the processing to a subsequent message, where
+      // the lock will not be held.
+      //
+      if (Util.SDK_INT < 30) {
+        handler.post(() -> {
+          if (this == tunnelingOnFrameRenderedListener) {   // event not stale
+            handleFrameRendered(presentationTimeUs);
+          }
+        });
+      } else {
+        handleFrameRendered(presentationTimeUs);
+      }
+    }
+
+    private void handleFrameRendered(long presentationTimeUs) {
       if (presentationTimeUs == TUNNELING_EOS_PRESENTATION_TIME_US) {
         onProcessedTunneledEndOfStream();
       } else {
         onProcessedTunneledBuffer(presentationTimeUs);
       }
     }
-
   }
 }