From 2c838fbd87ad5685c0008b419ea02421159b9b70 Mon Sep 17 00:00:00 2001
From: Robert Shih <robertshih@google.com>
Date: Thu, 21 May 2015 15:15:50 -0700
Subject: [PATCH] MediaPlayer: add mPreparing to weed out unwanted prepared
 messages

Bug: 21266735
Change-Id: Ie4fe76533c9b7f505c57ba63df7992f2490942cc
---
 media/java/android/media/MediaPlayer.java | 33 +++++++++++++++++++++--
 media/jni/android_media_MediaPlayer.cpp   |  2 +-
 2 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/media/java/android/media/MediaPlayer.java b/media/java/android/media/MediaPlayer.java
index f14860643c4b5..c24077eb20cd3 100644
--- a/media/java/android/media/MediaPlayer.java
+++ b/media/java/android/media/MediaPlayer.java
@@ -77,6 +77,7 @@ import java.util.Map;
 import java.util.Scanner;
 import java.util.Set;
 import java.util.Vector;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.lang.ref.WeakReference;
 
 /**
@@ -623,6 +624,9 @@ public class MediaPlayer implements SubtitleController.Listener
     private int mUsage = -1;
     private boolean mBypassInterruptionPolicy;
 
+    // use AtomicBoolean instead of boolean so we can use the same member both as a flag and a lock.
+    private AtomicBoolean mPreparing = new AtomicBoolean();
+
     /**
      * Default constructor. Consider using one of the create() methods for
      * synchronously instantiating a MediaPlayer from a Uri or resource.
@@ -1162,6 +1166,10 @@ public class MediaPlayer implements SubtitleController.Listener
      * @throws IllegalStateException if it is called in an invalid state
      */
     public void prepare() throws IOException, IllegalStateException {
+        // The synchronous version of prepare also recieves a MEDIA_PREPARED message.
+        synchronized (mPreparing) {
+            mPreparing.set(true);
+        }
         _prepare();
         scanInternalSubtitleTracks();
     }
@@ -1178,7 +1186,14 @@ public class MediaPlayer implements SubtitleController.Listener
      *
      * @throws IllegalStateException if it is called in an invalid state
      */
-    public native void prepareAsync() throws IllegalStateException;
+    public void prepareAsync() throws IllegalStateException {
+        synchronized (mPreparing) {
+            mPreparing.set(true);
+        }
+        _prepareAsync();
+    }
+
+    private native void _prepareAsync() throws IllegalStateException;
 
     /**
      * Starts or resumes playback. If playback had previously been paused,
@@ -1229,6 +1244,9 @@ public class MediaPlayer implements SubtitleController.Listener
      * initialized.
      */
     public void stop() throws IllegalStateException {
+        synchronized (mPreparing) {
+            mPreparing.set(false);
+        }
         stayAwake(false);
         _stop();
     }
@@ -1658,6 +1676,9 @@ public class MediaPlayer implements SubtitleController.Listener
      * at the same time.
      */
     public void release() {
+        synchronized (mPreparing) {
+            mPreparing.set(false);
+        }
         stayAwake(false);
         updateSurfaceScreenOn();
         mOnPreparedListener = null;
@@ -1684,6 +1705,9 @@ public class MediaPlayer implements SubtitleController.Listener
      * data source and calling prepare().
      */
     public void reset() {
+        synchronized (mPreparing) {
+            mPreparing.set(false);
+        }
         mSelectedSubtitleTrackIndex = -1;
         synchronized(mOpenSubtitleSources) {
             for (final InputStream is: mOpenSubtitleSources) {
@@ -2804,7 +2828,12 @@ public class MediaPlayer implements SubtitleController.Listener
             }
             switch(msg.what) {
             case MEDIA_PREPARED:
-                scanInternalSubtitleTracks();
+                synchronized (mPreparing) {
+                    if (mPreparing.get()) {
+                        scanInternalSubtitleTracks();
+                        mPreparing.set(false);
+                    }
+                }
                 if (mOnPreparedListener != null)
                     mOnPreparedListener.onPrepared(mMediaPlayer);
                 return;
diff --git a/media/jni/android_media_MediaPlayer.cpp b/media/jni/android_media_MediaPlayer.cpp
index d8041f4bff044..9c6727869478e 100644
--- a/media/jni/android_media_MediaPlayer.cpp
+++ b/media/jni/android_media_MediaPlayer.cpp
@@ -1045,7 +1045,7 @@ static JNINativeMethod gMethods[] = {
     {"_setDataSource",      "(Landroid/media/MediaDataSource;)V",(void *)android_media_MediaPlayer_setDataSourceCallback },
     {"_setVideoSurface",    "(Landroid/view/Surface;)V",        (void *)android_media_MediaPlayer_setVideoSurface},
     {"_prepare",            "()V",                              (void *)android_media_MediaPlayer_prepare},
-    {"prepareAsync",        "()V",                              (void *)android_media_MediaPlayer_prepareAsync},
+    {"_prepareAsync",       "()V",                              (void *)android_media_MediaPlayer_prepareAsync},
     {"_start",              "()V",                              (void *)android_media_MediaPlayer_start},
     {"_stop",               "()V",                              (void *)android_media_MediaPlayer_stop},
     {"getVideoWidth",       "()I",                              (void *)android_media_MediaPlayer_getVideoWidth},