MediaSessionRecord: add synchronize control for modification of mControllerCallbackHolders

// ArrayIndexOutOfBoundsException thrown when unregisterCallback()
03-13 18:57:16.455  2112  6787 E JavaBinder: *** Uncaught remote exception! Exceptions are not yet supported across processes. Client PID 3726 UID 1000.
03-13 18:57:16.455  2112  6787 E JavaBinder: java.lang.ArrayIndexOutOfBoundsException: length=0; index=1
03-13 18:57:16.455  2112  6787 E JavaBinder:  at java.util.concurrent.CopyOnWriteArrayList.elementAt(CopyOnWriteArrayList.java:389)
03-13 18:57:16.455  2112  6787 E JavaBinder:  at java.util.concurrent.CopyOnWriteArrayList.remove(CopyOnWriteArrayList.java:482)
03-13 18:57:16.455  2112  6787 E JavaBinder:  at com.android.server.media.MediaSessionRecord$ControllerStub.unregisterCallback(MediaSessionRecord.java:1714)
03-13 18:57:16.455  2112  6787 E JavaBinder:  at android.media.session.ISessionController$Stub.onTransact(ISessionController.java:394)
03-13 18:57:16.455  2112  6787 E JavaBinder:  at android.os.Binder.execTransactInternal(Binder.java:1351)
03-13 18:57:16.455  2112  6787 E JavaBinder:  at android.os.Binder.execTransact(Binder.java:1282)

Change-Id: I02c3011ac8d27171016dd15ce7dbbadff4a2bb65
Signed-off-by: wumin3 <wumin3@xiaomi.com>

1 files changed, 19 insertions, 8 deletions

diff --git a/services/core/java/com/android/server/media/MediaSessionRecord.java b/services/core/java/com/android/server/media/MediaSessionRecord.java
index 994d3ca1124f..6f8a46be089f 100644
--- a/services/core/java/com/android/server/media/MediaSessionRecord.java
+++ b/services/core/java/com/android/server/media/MediaSessionRecord.java
@@ -786,7 +786,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
             }
         }
         if (deadCallbackHolders != null) {
-            mControllerCallbackHolders.removeAll(deadCallbackHolders);
+            removeControllerHoldersSafely(deadCallbackHolders);
         }
     }
 
@@ -813,7 +813,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
             }
         }
         if (deadCallbackHolders != null) {
-            mControllerCallbackHolders.removeAll(deadCallbackHolders);
+            removeControllerHoldersSafely(deadCallbackHolders);
         }
     }
 
@@ -848,7 +848,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
             }
         }
         if (deadCallbackHolders != null) {
-            mControllerCallbackHolders.removeAll(deadCallbackHolders);
+            removeControllerHoldersSafely(deadCallbackHolders);
         }
     }
 
@@ -875,7 +875,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
             }
         }
         if (deadCallbackHolders != null) {
-            mControllerCallbackHolders.removeAll(deadCallbackHolders);
+            removeControllerHoldersSafely(deadCallbackHolders);
         }
     }
 
@@ -902,7 +902,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
             }
         }
         if (deadCallbackHolders != null) {
-            mControllerCallbackHolders.removeAll(deadCallbackHolders);
+            removeControllerHoldersSafely(deadCallbackHolders);
         }
     }
 
@@ -929,7 +929,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
             }
         }
         if (deadCallbackHolders != null) {
-            mControllerCallbackHolders.removeAll(deadCallbackHolders);
+            removeControllerHoldersSafely(deadCallbackHolders);
         }
     }
 
@@ -954,7 +954,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
             }
         }
         if (deadCallbackHolders != null) {
-            mControllerCallbackHolders.removeAll(deadCallbackHolders);
+            removeControllerHoldersSafely(deadCallbackHolders);
         }
     }
 
@@ -979,7 +979,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
             }
         }
         // After notifying clear all listeners
-        mControllerCallbackHolders.clear();
+        removeControllerHoldersSafely(null);
     }
 
     private PlaybackState getStateWithUpdatedPosition() {
@@ -1027,6 +1027,17 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
         return -1;
     }
 
+    private void removeControllerHoldersSafely(
+            Collection<ISessionControllerCallbackHolder> holders) {
+        synchronized (mLock) {
+            if (holders == null) {
+                mControllerCallbackHolders.clear();
+            } else {
+                mControllerCallbackHolders.removeAll(holders);
+            }
+        }
+    }
+
     private PlaybackInfo getVolumeAttributes() {
         int volumeType;
         AudioAttributes attributes;