PeerConnection(iOS): make ARC-clean talk/.../objc* and talk/examples/ios

- Removes a strong-reference cycle between RTCPeerConnection and
  RTCPeerConnectionObserver
- Gives RTCPeerConnectionObserver a virtual dtor
- Ensures RTCPeerConnectionTest tears down correctly
- Ensures AppRTCDemo tears down correctly

This is the talk/ half; the webrtc/ half is in https://webrtc-codereview.appspot.com/10539005

BUG=3054,3055,3100
R=noahric@google.com

Review URL: https://webrtc-codereview.appspot.com/10499005

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5771 4adac7df-926f-26a2-2b94-8c16560cd09d

talk/app/webrtc/objc/RTCPeerConnectionObserver.h

@@ -39,7 +39,9 @@ class RTCPeerConnectionObserver : public PeerConnectionObserver {
 
  public:
   explicit RTCPeerConnectionObserver(id<RTCPeerConnectionDelegate> delegate);
+  virtual ~RTCPeerConnectionObserver();
 
+  // |peerConnection| owns |this|, so outlives it.
   void SetPeerConnection(RTCPeerConnection *peerConnection);
 
   virtual void OnError() OVERRIDE;
@@ -73,7 +75,9 @@ class RTCPeerConnectionObserver : public PeerConnectionObserver {
 
  private:
   id<RTCPeerConnectionDelegate> _delegate;
-  RTCPeerConnection *_peerConnection;
+  // __unsafe_unretained is in fact safe because |_peerConnection| owns |this|;
+  // see comment on SetPeerConnection() above.
+  __unsafe_unretained RTCPeerConnection *_peerConnection;
 };
 
 } // namespace webrtc

talk/app/webrtc/objc/RTCPeerConnectionObserver.mm

@@ -42,6 +42,8 @@ RTCPeerConnectionObserver::RTCPeerConnectionObserver(
   _delegate = delegate;
 }
 
+RTCPeerConnectionObserver::~RTCPeerConnectionObserver() {}
+
 void RTCPeerConnectionObserver::SetPeerConnection(
     RTCPeerConnection* peerConnection) {
   _peerConnection = peerConnection;

talk/app/webrtc/objctests/RTCPeerConnectionTest.mm

@@ -59,7 +59,7 @@
                                 videoTrackID:(NSString*)videoTrackID
                                 audioTrackID:(NSString*)audioTrackID;
 
-- (void)testCompleteSession;
+- (void)testCompleteSessionWithFactory:(RTCPeerConnectionFactory*)factory;
 
 @end
 
@@ -93,8 +93,7 @@
   return localMediaStream;
 }
 
-- (void)testCompleteSession {
+- (void)testCompleteSessionWithFactory:(RTCPeerConnectionFactory*)factory {
-  RTCPeerConnectionFactory* factory = [[RTCPeerConnectionFactory alloc] init];
   RTCMediaConstraints* constraints = [[RTCMediaConstraints alloc] init];
   RTCPeerConnectionSyncObserver* offeringExpectations =
       [[RTCPeerConnectionSyncObserver alloc] init];
@@ -216,7 +215,24 @@
   [[NSRunLoop currentRunLoop]
       runUntilDate:[NSDate dateWithTimeIntervalSinceNow:2]];
 
-  // TODO(hughv): Implement orderly shutdown.
+  [offeringExpectations expectICEConnectionChange:RTCICEConnectionClosed];
+  [answeringExpectations expectICEConnectionChange:RTCICEConnectionClosed];
+  [offeringExpectations expectSignalingChange:RTCSignalingClosed];
+  [answeringExpectations expectSignalingChange:RTCSignalingClosed];
+
+  [pcOffer close];
+  [pcAnswer close];
+
+  [offeringExpectations waitForAllExpectationsToBeSatisfied];
+  [answeringExpectations waitForAllExpectationsToBeSatisfied];
+
+  capturer = nil;
+  videoSource = nil;
+  pcOffer = nil;
+  pcAnswer = nil;
+  // TODO(fischman): be stricter about shutdown checks; ensure thread
+  // counts return to where they were before the test kicked off, and
+  // that all objects have in fact shut down.
 }
 
 @end
@@ -225,8 +241,20 @@
 // RTCPeerConnectionTest and avoid the appearance of RTCPeerConnectionTest being
 // a TestBase since it's not.
 TEST(RTCPeerConnectionTest, SessionTest) {
+  @autoreleasepool {
     talk_base::InitializeSSL();
+    // Since |factory| will own the signaling & worker threads, it's important
+    // that it outlive the created PeerConnections since they self-delete on the
+    // signaling thread, and if |factory| is freed first then a last refcount on
+    // the factory will expire during this teardown, causing the signaling
+    // thread to try to Join() with itself.  This is a hack to ensure that the
+    // factory outlives RTCPeerConnection:dealloc.
+    // See https://code.google.com/p/webrtc/issues/detail?id=3100.
+    RTCPeerConnectionFactory* factory = [[RTCPeerConnectionFactory alloc] init];
+    @autoreleasepool {
       RTCPeerConnectionTest* pcTest = [[RTCPeerConnectionTest alloc] init];
-  [pcTest testCompleteSession];
+      [pcTest testCompleteSessionWithFactory:factory];
+    }
     talk_base::CleanupSSL();
+  }
 }

talk/app/webrtc/objctests/mac/main.mm

@@ -27,6 +27,10 @@
 
 #include "talk/base/gunit.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 int main(int argc, char* argv[]) {
   testing::InitGoogleTest(&argc, argv);
   return RUN_ALL_TESTS();

talk/examples/ios/AppRTCDemo/APPRTCAppDelegate.h

@@ -30,7 +30,7 @@
 #import "GAEChannelClient.h"
 #import "APPRTCAppClient.h"
 #import "RTCSessionDescriptonDelegate.h"
-
+#import "RTCVideoSource.h"
 // Used to send a message to an apprtc.appspot.com "room".
 @protocol APPRTCSendMessage<NSObject>
 
@@ -43,7 +43,7 @@
 @class RTCVideoTrack;
 
 // The main application class of the AppRTCDemo iOS app demonstrating
-// interoperability between the Objcective C implementation of PeerConnection
+// interoperability between the Objective C implementation of PeerConnection
 // and the apprtc.appspot.com demo webapp.
 @interface APPRTCAppDelegate : UIResponder<ICEServerDelegate,
                                            GAEMessageHandler,
@@ -53,6 +53,7 @@
 
 @property(strong, nonatomic) UIWindow* window;
 @property(strong, nonatomic) APPRTCViewController* viewController;
+@property (strong, nonatomic) RTCVideoSource* videoSource;
 
 - (void)closeVideoUI;
 

talk/examples/ios/AppRTCDemo/APPRTCAppDelegate.m

@@ -246,12 +246,12 @@
 
   RTCVideoCapturer* capturer =
       [RTCVideoCapturer capturerWithDeviceName:cameraID];
-  RTCVideoSource* videoSource = [self.peerConnectionFactory
+  self.videoSource = [self.peerConnectionFactory
       videoSourceWithCapturer:capturer
                   constraints:self.client.videoConstraints];
   RTCVideoTrack* localVideoTrack =
       [self.peerConnectionFactory videoTrackWithID:@"ARDAMSv0"
-                                            source:videoSource];
+                                            source:self.videoSource];
   if (localVideoTrack) {
     [lms addVideoTrack:localVideoTrack];
   }
@@ -485,9 +485,10 @@
       sendData:[@"{\"type\": \"bye\"}" dataUsingEncoding:NSUTF8StringEncoding]];
   [self.peerConnection close];
   self.peerConnection = nil;
-  self.peerConnectionFactory = nil;
   self.pcObserver = nil;
   self.client = nil;
+  self.videoSource = nil;
+  self.peerConnectionFactory = nil;
   [RTCPeerConnectionFactory deinitializeSSL];
 }
 
@@ -523,8 +524,8 @@
 #pragma mark - public methods
 
 - (void)closeVideoUI {
-  [self disconnect];
   [self.viewController resetUI];
+  [self disconnect];
 }
 
 @end

talk/examples/ios/AppRTCDemo/APPRTCViewController.m

@@ -77,7 +77,7 @@
   [_remoteVideoView removeFromSuperview];
   self.remoteVideoView = nil;
 
-  [_remoteVideoView renderVideoTrackInterface:nil];
+  [_localVideoView renderVideoTrackInterface:nil];
   [_localVideoView removeFromSuperview];
   self.localVideoView = nil;
 }