Bug 1426129 - Hold CamerasChild via promoting "this" to a RefPtr. r=jib

MozReview-Commit-ID: JdZqnGxlsBV

dom/media/systemservices/CamerasChild.cpp

@@ -290,10 +290,11 @@ CamerasChild::NumberOfCapabilities(CaptureEngine aCapEngine,
   LOG((__PRETTY_FUNCTION__));
   LOG(("NumberOfCapabilities for %s", deviceUniqueIdUTF8));
   nsCString unique_id(deviceUniqueIdUTF8);
+  RefPtr<CamerasChild> self(this);
   nsCOMPtr<nsIRunnable> runnable =
     mozilla::NewNonOwningRunnableMethod<CaptureEngine, nsCString>(
       "camera::PCamerasChild::SendNumberOfCapabilities",
-      this,
+      self,
       &CamerasChild::SendNumberOfCapabilities,
       aCapEngine,
       unique_id);
@@ -306,10 +307,11 @@ int
 CamerasChild::NumberOfCaptureDevices(CaptureEngine aCapEngine)
 {
   LOG((__PRETTY_FUNCTION__));
+  RefPtr<CamerasChild> self(this);
   nsCOMPtr<nsIRunnable> runnable =
     mozilla::NewNonOwningRunnableMethod<CaptureEngine>(
       "camera::PCamerasChild::SendNumberOfCaptureDevices",
-      this,
+      self,
       &CamerasChild::SendNumberOfCaptureDevices,
       aCapEngine);
   LockAndDispatch<> dispatcher(this, __func__, runnable, 0, mReplyInteger);
@@ -333,10 +335,11 @@ int
 CamerasChild::EnsureInitialized(CaptureEngine aCapEngine)
 {
   LOG((__PRETTY_FUNCTION__));
+  RefPtr<CamerasChild> self(this);
   nsCOMPtr<nsIRunnable> runnable =
     mozilla::NewNonOwningRunnableMethod<CaptureEngine>(
       "camera::PCamerasChild::SendEnsureInitialized",
-      this,
+      self,
       &CamerasChild::SendEnsureInitialized,
       aCapEngine);
   LockAndDispatch<> dispatcher(this, __func__, runnable, 0, mReplyInteger);
@@ -352,10 +355,11 @@ CamerasChild::GetCaptureCapability(CaptureEngine aCapEngine,
 {
   LOG(("GetCaptureCapability: %s %d", unique_idUTF8, capability_number));
   nsCString unique_id(unique_idUTF8);
+  RefPtr<CamerasChild> self(this);
   nsCOMPtr<nsIRunnable> runnable =
     mozilla::NewNonOwningRunnableMethod<CaptureEngine, nsCString, unsigned int>(
       "camera::PCamerasChild::SendGetCaptureCapability",
-      this,
+      self,
       &CamerasChild::SendGetCaptureCapability,
       aCapEngine,
       unique_id,
@@ -394,10 +398,11 @@ CamerasChild::GetCaptureDevice(CaptureEngine aCapEngine,
                                bool* scary)
 {
   LOG((__PRETTY_FUNCTION__));
+  RefPtr<CamerasChild> self(this);
   nsCOMPtr<nsIRunnable> runnable =
     mozilla::NewNonOwningRunnableMethod<CaptureEngine, unsigned int>(
       "camera::PCamerasChild::SendGetCaptureDevice",
-      this,
+      self,
       &CamerasChild::SendGetCaptureDevice,
       aCapEngine,
       list_number);
@@ -438,12 +443,13 @@ CamerasChild::AllocateCaptureDevice(CaptureEngine aCapEngine,
 {
   LOG((__PRETTY_FUNCTION__));
   nsCString unique_id(unique_idUTF8);
+  RefPtr<CamerasChild> self(this);
   nsCOMPtr<nsIRunnable> runnable =
     mozilla::NewNonOwningRunnableMethod<CaptureEngine,
                                         nsCString,
                                         const mozilla::ipc::PrincipalInfo&>(
       "camera::PCamerasChild::SendAllocateCaptureDevice",
-      this,
+      self,
       &CamerasChild::SendAllocateCaptureDevice,
       aCapEngine,
       unique_id,
@@ -474,10 +480,11 @@ CamerasChild::ReleaseCaptureDevice(CaptureEngine aCapEngine,
                                    const int capture_id)
 {
   LOG((__PRETTY_FUNCTION__));
+  RefPtr<CamerasChild> self(this);
   nsCOMPtr<nsIRunnable> runnable =
     mozilla::NewNonOwningRunnableMethod<CaptureEngine, int>(
       "camera::PCamerasChild::SendReleaseCaptureDevice",
-      this,
+      self,
       &CamerasChild::SendReleaseCaptureDevice,
       aCapEngine,
       capture_id);
@@ -525,10 +532,11 @@ CamerasChild::StartCapture(CaptureEngine aCapEngine,
                            webrtcCaps.rawType,
                            webrtcCaps.codecType,
                            webrtcCaps.interlaced);
+  RefPtr<CamerasChild> self(this);
   nsCOMPtr<nsIRunnable> runnable = mozilla::
     NewNonOwningRunnableMethod<CaptureEngine, int, VideoCaptureCapability>(
       "camera::PCamerasChild::SendStartCapture",
-      this,
+      self,
       &CamerasChild::SendStartCapture,
       aCapEngine,
       capture_id,
@@ -541,10 +549,11 @@ int
 CamerasChild::StopCapture(CaptureEngine aCapEngine, const int capture_id)
 {
   LOG((__PRETTY_FUNCTION__));
+  RefPtr<CamerasChild> self(this);
   nsCOMPtr<nsIRunnable> runnable =
     mozilla::NewNonOwningRunnableMethod<CaptureEngine, int>(
       "camera::PCamerasChild::SendStopCapture",
-      this,
+      self,
       &CamerasChild::SendStopCapture,
       aCapEngine,
       capture_id);
@@ -610,8 +619,9 @@ CamerasChild::ShutdownParent()
     // Delete the parent actor.
     // CamerasChild (this) will remain alive and is only deleted by the
     // IPC layer when SendAllDone returns.
+    RefPtr<CamerasChild> self(this);
     nsCOMPtr<nsIRunnable> deleteRunnable = mozilla::NewNonOwningRunnableMethod(
-      "camera::PCamerasChild::SendAllDone", this, &CamerasChild::SendAllDone);
+      "camera::PCamerasChild::SendAllDone", self, &CamerasChild::SendAllDone);
     CamerasSingleton::Thread()->Dispatch(deleteRunnable, NS_DISPATCH_NORMAL);
   } else {
     LOG(("ShutdownParent called without PBackground thread"));

dom/media/systemservices/CamerasChild.h

@@ -148,7 +148,7 @@ class CamerasChild final : public PCamerasChild
 public:
   // We are owned by the PBackground thread only. CamerasSingleton
   // takes a non-owning reference.
-  NS_INLINE_DECL_REFCOUNTING(CamerasChild)
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(CamerasChild)
 
   // IPC messages recevied, received on the PBackground thread
   // these are the actual callbacks with data