From 23b08eb531aef7d2c69512622c46cf2dab965207 Mon Sep 17 00:00:00 2001
From: magjed <magjed@webrtc.org>
Date: Tue, 5 Apr 2016 01:37:04 -0700
Subject: [PATCH] Android VideoCapture: Add null checks in
 stopCaptureOnCameraThread

If stopCapture is called shortly after startCapture, and the first startCaptureOnCameraThread failed, but still hasn't retried 3 times, stopCaptureOnCameraThread will be called in a state where the camera is not initialized. This CL adds null checks in stopCaptureOnCameraThread to avoid crashes.

BUG=b/27939867

Review URL: https://codereview.webrtc.org/1854103002

Cr-Commit-Position: refs/heads/master@{#12234}
---
 .../org/webrtc/VideoCapturerAndroid.java      | 24 ++++++++++++-------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/webrtc/api/java/android/org/webrtc/VideoCapturerAndroid.java b/webrtc/api/java/android/org/webrtc/VideoCapturerAndroid.java
index b8ab1a8c5e..93e623e4bd 100644
--- a/webrtc/api/java/android/org/webrtc/VideoCapturerAndroid.java
+++ b/webrtc/api/java/android/org/webrtc/VideoCapturerAndroid.java
@@ -467,10 +467,8 @@ public class VideoCapturerAndroid implements
       error = e;
     }
     Logging.e(TAG, "startCapture failed", error);
-    if (camera != null) {
-      // Make sure the camera is released.
-      stopCaptureOnCameraThread();
-    }
+    // Make sure the camera is released.
+    stopCaptureOnCameraThread();
     synchronized (handlerLock) {
       // Remove all pending Runnables posted from |this|.
       cameraThreadHandler.removeCallbacksAndMessages(this /* token */);
@@ -607,20 +605,28 @@ public class VideoCapturerAndroid implements
   private void stopCaptureOnCameraThread() {
     checkIsOnCameraThread();
     Logging.d(TAG, "stopCaptureOnCameraThread");
+    // Note that the camera might still not be started here if startCaptureOnCameraThread failed
+    // and we posted a retry.
 
     // Make sure onTextureFrameAvailable() is not called anymore.
-    surfaceHelper.stopListening();
+    if (surfaceHelper != null) {
+      surfaceHelper.stopListening();
+    }
     cameraThreadHandler.removeCallbacks(cameraObserver);
     cameraStatistics.getAndResetFrameCount();
     Logging.d(TAG, "Stop preview.");
-    camera.stopPreview();
-    camera.setPreviewCallbackWithBuffer(null);
+    if (camera != null) {
+      camera.stopPreview();
+      camera.setPreviewCallbackWithBuffer(null);
+    }
     queuedBuffers.clear();
     captureFormat = null;
 
     Logging.d(TAG, "Release camera.");
-    camera.release();
-    camera = null;
+    if (camera != null) {
+      camera.release();
+      camera = null;
+    }
     if (eventsHandler != null) {
       eventsHandler.onCameraClosed();
     }