Revert of Remove references between RTCPeerConnection and RTCDataChannel.

third_party/WebKit/Source/modules/mediastream/RTCDataChannel.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 33 matching lines @@
 static void throwCouldNotSendDataException(ExceptionState& exceptionState)
 {
     exceptionState.throwDOMException(NetworkError, "Could not send data");
 }
 
 static void throwNoBlobSupportException(ExceptionState& exceptionState)
 {
     exceptionState.throwDOMException(NotSupportedError, "Blob support not implemented yet");
 }
 
-RTCDataChannel* RTCDataChannel::create(ExecutionContext* context, PassOwnPtr<WebRTCDataChannelHandler> handler)
+RTCDataChannel* RTCDataChannel::create(ExecutionContext* context, RTCPeerConnection* connection, PassOwnPtr<WebRTCDataChannelHandler> handler)
 {
     ASSERT(handler);
-    return new RTCDataChannel(context, handler);
+    return new RTCDataChannel(context, connection, handler);
 }
 
-RTCDataChannel* RTCDataChannel::create(ExecutionContext* context, WebRTCPeerConnectionHandler* peerConnectionHandler, const String& label, const WebRTCDataChannelInit& init, ExceptionState& exceptionState)
+RTCDataChannel* RTCDataChannel::create(ExecutionContext* context, RTCPeerConnection* connection, WebRTCPeerConnectionHandler* peerConnectionHandler, const String& label, const WebRTCDataChannelInit& init, ExceptionState& exceptionState)
 {
     OwnPtr<WebRTCDataChannelHandler> handler = adoptPtr(peerConnectionHandler->createDataChannel(label, init));
     if (!handler) {
         exceptionState.throwDOMException(NotSupportedError, "RTCDataChannel is not supported");
         return nullptr;
     }
-    return new RTCDataChannel(context, handler.release());
+    return new RTCDataChannel(context, connection, handler.release());
 }
 
-RTCDataChannel::RTCDataChannel(ExecutionContext* context, PassOwnPtr<WebRTCDataChannelHandler> handler)
+RTCDataChannel::RTCDataChannel(ExecutionContext* context, RTCPeerConnection* connection, PassOwnPtr<WebRTCDataChannelHandler> handler)
     : m_executionContext(context)
     , m_handler(handler)
+    , m_stopped(false)
     , m_readyState(ReadyStateConnecting)
     , m_binaryType(BinaryTypeArrayBuffer)
     , m_scheduledEventTimer(this, &RTCDataChannel::scheduledEventTimerFired)
+    , m_connection(connection)
     , m_bufferedAmountLowThreshold(0U)
 {
     m_handler->setClient(this);
 }
 
 RTCDataChannel::~RTCDataChannel()
 {
-    // Notify the client that the channel is gone.
-    m_handler->setClient(0);
+    // If the peer connection and the data channel die in the same
+    // GC cycle stop has not been called and we need to notify the
+    // client that the channel is gone.
+    if (!m_stopped)
+        m_handler->setClient(0);
 }
 
 RTCDataChannel::ReadyState RTCDataChannel::getHandlerState() const
 {
     return m_handler->state();
 }
 
 String RTCDataChannel::label() const
 {
     return m_handler->label();
@@ skipping 128 matching lines @@
 }
 
 void RTCDataChannel::send(Blob* data, ExceptionState& exceptionState)
 {
     // FIXME: implement
     throwNoBlobSupportException(exceptionState);
 }
 
 void RTCDataChannel::close()
 {
+    if (m_stopped)
+        return;
+
     m_handler->close();
 }
 
 void RTCDataChannel::didChangeReadyState(WebRTCDataChannelHandlerClient::ReadyState newState)
 {
-    if (m_readyState == ReadyStateClosed)
+    if (m_stopped || m_readyState == ReadyStateClosed)
         return;
 
     m_readyState = newState;
 
     switch (m_readyState) {
     case ReadyStateOpen:
         scheduleDispatchEvent(Event::create(EventTypeNames::open));
         break;
     case ReadyStateClosed:
         scheduleDispatchEvent(Event::create(EventTypeNames::close));
         break;
     default:
         break;
     }
 }
 
 void RTCDataChannel::didDecreaseBufferedAmount(unsigned previousAmount)
 {
     if (previousAmount > m_bufferedAmountLowThreshold
         && bufferedAmount() <= m_bufferedAmountLowThreshold) {
         scheduleDispatchEvent(Event::create(EventTypeNames::bufferedamountlow));
     }
 }
 
 void RTCDataChannel::didReceiveStringData(const WebString& text)
 {
+    if (m_stopped)
+        return;
+
     scheduleDispatchEvent(MessageEvent::create(text));
 }
 
 void RTCDataChannel::didReceiveRawData(const char* data, size_t dataLength)
 {
+    if (m_stopped)
+        return;
+
     if (m_binaryType == BinaryTypeBlob) {
         // FIXME: Implement.
         return;
     }
     if (m_binaryType == BinaryTypeArrayBuffer) {
         RefPtr<DOMArrayBuffer> buffer = DOMArrayBuffer::create(data, dataLength);
         scheduleDispatchEvent(MessageEvent::create(buffer.release()));
         return;
     }
     ASSERT_NOT_REACHED();
 }
 
 void RTCDataChannel::didDetectError()
 {
+    if (m_stopped)
+        return;
+
     scheduleDispatchEvent(Event::create(EventTypeNames::error));
 }
 
 const AtomicString& RTCDataChannel::interfaceName() const
 {
     return EventTargetNames::RTCDataChannel;
 }
 
 ExecutionContext* RTCDataChannel::executionContext() const
 {
     return m_executionContext;
 }
 
+void RTCDataChannel::stop()
+{
+    m_stopped = true;
+    m_readyState = ReadyStateClosed;
+    m_handler->setClient(0);
+    m_executionContext = 0;
+}
+
 void RTCDataChannel::scheduleDispatchEvent(PassRefPtrWillBeRawPtr<Event> event)
 {
     m_scheduledEvents.append(event);
 
     if (!m_scheduledEventTimer.isActive())
         m_scheduledEventTimer.startOneShot(0, BLINK_FROM_HERE);
 }
 
 void RTCDataChannel::scheduledEventTimerFired(Timer<RTCDataChannel>*)
 {
+    if (m_stopped)
+        return;
+
     WillBeHeapVector<RefPtrWillBeMember<Event>> events;
     events.swap(m_scheduledEvents);
 
     WillBeHeapVector<RefPtrWillBeMember<Event>>::iterator it = events.begin();
     for (; it != events.end(); ++it)
         dispatchEvent((*it).release());
 
     events.clear();
 }
 
+void RTCDataChannel::clearWeakMembers(Visitor* visitor)
+{
+    if (Heap::isHeapObjectAlive(m_connection))
+        return;
+    stop();
+    m_connection = nullptr;
+}
+
 DEFINE_TRACE(RTCDataChannel)
 {
     visitor->trace(m_executionContext);
     visitor->trace(m_scheduledEvents);
+    visitor->template registerWeakMembers<RTCDataChannel, &RTCDataChannel::clearWeakMembers>(this);
     RefCountedGarbageCollectedEventTargetWithInlineData<RTCDataChannel>::trace(visitor);
 }
 
 } // namespace blink