From 0fed7e62bfa0d8351b91d3531228a113637963a3 Mon Sep 17 00:00:00 2001
From: Sascha Haeberling <haeberling@google.com>
Date: Mon, 14 Apr 2014 14:41:57 -0700
Subject: [PATCH] Safeguard callback receiver to prevent crashes.

  Bug: 13765929

It is safe to add these checks here. The receiver is only set in
the constructor, and it's only created in one place, which is
onCreate. And the parameter is the Activity itself, so it can
never be null.
This means the NPE can only happen if onCameraOpened is called after
removeCallbackReceiver is called, which is in onDestroy of the activity.
In this case it's safe to exit.

Change-Id: Ibffd6d54679b564a11b3e83319896241f2e306ad
---
 src/com/android/camera/app/CameraController.java | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/src/com/android/camera/app/CameraController.java b/src/com/android/camera/app/CameraController.java
index 78edb971a..560705a84 100644
--- a/src/com/android/camera/app/CameraController.java
+++ b/src/com/android/camera/app/CameraController.java
@@ -130,32 +130,42 @@ public class CameraController implements CameraManager.CameraOpenCallback, Camer
     @Override
     public void onCameraOpened(CameraManager.CameraProxy camera) {
         mCameraProxy = camera;
-        if(mRequestingCameraId == EMPTY_REQUEST) {
+        if (mRequestingCameraId == EMPTY_REQUEST) {
             // Not requesting any camera.
             return;
         }
         mRequestingCameraId = EMPTY_REQUEST;
-        mCallbackReceiver.onCameraOpened(camera);
+        if (mCallbackReceiver != null) {
+            mCallbackReceiver.onCameraOpened(camera);
+        }
     }
 
     @Override
     public void onCameraDisabled(int cameraId) {
-        mCallbackReceiver.onCameraDisabled(cameraId);
+        if (mCallbackReceiver != null) {
+            mCallbackReceiver.onCameraDisabled(cameraId);
+        }
     }
 
     @Override
     public void onDeviceOpenFailure(int cameraId) {
-        mCallbackReceiver.onDeviceOpenFailure(cameraId);
+        if (mCallbackReceiver != null) {
+            mCallbackReceiver.onDeviceOpenFailure(cameraId);
+        }
     }
 
     @Override
     public void onDeviceOpenedAlready(int cameraId) {
-        mCallbackReceiver.onDeviceOpenedAlready(cameraId);
+        if (mCallbackReceiver != null) {
+            mCallbackReceiver.onDeviceOpenedAlready(cameraId);
+        }
     }
 
     @Override
     public void onReconnectionFailure(CameraManager mgr) {
-        mCallbackReceiver.onReconnectionFailure(mgr);
+        if (mCallbackReceiver != null) {
+            mCallbackReceiver.onReconnectionFailure(mgr);
+        }
     }
 
     @Override
-- 
2.11.0