Fix reference cycle in InputEventReceiver and Sender.

If the receiver or sender was not properly disposed, then
the underlying input channel might be leaked because the
native peer was holding a strong reference to the object.

Switched to using a weak reference.

Also updated Binder to use a new helper created for this purpose.

Change-Id: I19680bf96d0548777bff02aa1d91874d1e8e41da

2 files changed, 10 insertions, 4 deletions

diff --git a/core/java/android/view/InputEventReceiver.java b/core/java/android/view/InputEventReceiver.java
index 117c101..f5ee7ed 100644
--- a/core/java/android/view/InputEventReceiver.java
+++ b/core/java/android/view/InputEventReceiver.java
@@ -23,6 +23,8 @@ import android.os.MessageQueue;
 import android.util.Log;
 import android.util.SparseIntArray;
 
+import java.lang.ref.WeakReference;
+
 /**
  * Provides a low-level mechanism for an application to receive input events.
  * @hide
@@ -42,7 +44,7 @@ public abstract class InputEventReceiver {
     // Map from InputEvent sequence numbers to dispatcher sequence numbers.
     private final SparseIntArray mSeqMap = new SparseIntArray();
 
-    private static native int nativeInit(InputEventReceiver receiver,
+    private static native int nativeInit(WeakReference<InputEventReceiver> receiver,
             InputChannel inputChannel, MessageQueue messageQueue);
     private static native void nativeDispose(int receiverPtr);
     private static native void nativeFinishInputEvent(int receiverPtr, int seq, boolean handled);
@@ -65,7 +67,8 @@ public abstract class InputEventReceiver {
 
         mInputChannel = inputChannel;
         mMessageQueue = looper.getQueue();
-        mReceiverPtr = nativeInit(this, inputChannel, mMessageQueue);
+        mReceiverPtr = nativeInit(new WeakReference<InputEventReceiver>(this),
+                inputChannel, mMessageQueue);
 
         mCloseGuard.open("dispose");
     }
diff --git a/core/java/android/view/InputEventSender.java b/core/java/android/view/InputEventSender.java
index adf63fe..be6a623 100644
--- a/core/java/android/view/InputEventSender.java
+++ b/core/java/android/view/InputEventSender.java
@@ -22,6 +22,8 @@ import android.os.Looper;
 import android.os.MessageQueue;
 import android.util.Log;
 
+import java.lang.ref.WeakReference;
+
 /**
  * Provides a low-level mechanism for an application to send input events.
  * @hide
@@ -38,7 +40,7 @@ public abstract class InputEventSender {
     private InputChannel mInputChannel;
     private MessageQueue mMessageQueue;
 
-    private static native int nativeInit(InputEventSender sender,
+    private static native int nativeInit(WeakReference<InputEventSender> sender,
             InputChannel inputChannel, MessageQueue messageQueue);
     private static native void nativeDispose(int senderPtr);
     private static native boolean nativeSendKeyEvent(int senderPtr, int seq, KeyEvent event);
@@ -60,7 +62,8 @@ public abstract class InputEventSender {
 
         mInputChannel = inputChannel;
         mMessageQueue = looper.getQueue();
-        mSenderPtr = nativeInit(this, inputChannel, mMessageQueue);
+        mSenderPtr = nativeInit(new WeakReference<InputEventSender>(this),
+                inputChannel, mMessageQueue);
 
         mCloseGuard.open("dispose");
     }