Worker: Introduce an observation mechanism for WorkerThread termination

third_party/WebKit/Source/modules/websockets/WorkerWebSocketChannel.h

 /*
  * Copyright (C) 2011 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 14 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef WorkerWebSocketChannel_h
 #define WorkerWebSocketChannel_h
 
 #include "bindings/core/v8/SourceLocation.h"
+#include "core/workers/WorkerThreadLifecycleObserver.h"
 #include "modules/websockets/WebSocketChannel.h"
 #include "modules/websockets/WebSocketChannelClient.h"
 #include "platform/heap/Handle.h"
 #include "platform/v8_inspector/public/ConsoleTypes.h"
 #include "wtf/Assertions.h"
 #include "wtf/Forward.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/RefPtr.h"
 #include "wtf/Vector.h"
 #include "wtf/text/WTFString.h"
@@ skipping 31 matching lines @@
     {
         ASSERT_NOT_REACHED();
     }
     void close(int code, const String& reason) override;
     void fail(const String& reason, MessageLevel, PassOwnPtr<SourceLocation>) override;
     void disconnect() override; // Will suppress didClose().
 
     DECLARE_VIRTUAL_TRACE();
 
     class Bridge;
-    // Allocated in the worker thread, but used in the main thread.
-    class Peer final : public GarbageCollectedFinalized<Peer>, public WebSocketChannelClient {
+    // Allocated and used in the main thread, but destructed in the worker

[yhirano, 2016/06/09 04:55:13]

|Peer| is an on-heap class so it will be destructed on the allocated thread.

[nhiroki, 2016/06/09 07:37:07]

Done.

+    // thread.
+    class Peer final : public GarbageCollectedFinalized<Peer>, public WebSocketChannelClient, public WorkerThreadLifecycleObserver {
         USING_GARBAGE_COLLECTED_MIXIN(Peer);
         WTF_MAKE_NONCOPYABLE(Peer);
     public:
-        Peer(Bridge*, PassRefPtr<WorkerLoaderProxy>, WebSocketChannelSyncHelper*);
+        Peer(Bridge*, PassRefPtr<WorkerLoaderProxy>, WebSocketChannelSyncHelper*, WorkerThreadContext*);
         ~Peer() override;
 
         // SourceLocation parameter may be shown when the connection fails.
         void initialize(PassOwnPtr<SourceLocation>, ExecutionContext*);
 
         void connect(const KURL&, const String& protocol);
         void sendTextAsCharVector(PassOwnPtr<Vector<char>>);
         void sendBinaryAsCharVector(PassOwnPtr<Vector<char>>);
         void sendBlob(PassRefPtr<BlobDataHandle>);
         void close(int code, const String& reason);
         void fail(const String& reason, MessageLevel, PassOwnPtr<SourceLocation>);
         void disconnect();
 
         DECLARE_VIRTUAL_TRACE();
 
         // WebSocketChannelClient functions.
         void didConnect(const String& subprotocol, const String& extensions) override;
         void didReceiveTextMessage(const String& payload) override;
         void didReceiveBinaryMessage(PassOwnPtr<Vector<char>>) override;
         void didConsumeBufferedAmount(uint64_t) override;
         void didStartClosingHandshake() override;
         void didClose(ClosingHandshakeCompletionStatus, unsigned short code, const String& reason) override;
         void didError() override;
 
+        // WorkerThreadLifecycleObserver function.
+        void contextDestroyed() override;
+
     private:
         Member<Bridge> m_bridge;

[yhirano, 2016/06/09 04:55:13]

If you use CrossThreadPersistent in Member, this should be
CrossThreadWeakPersistent.

[nhiroki, 2016/06/09 07:37:07]

Done.

         RefPtr<WorkerLoaderProxy> m_loaderProxy;
         Member<WebSocketChannel> m_mainWebSocketChannel;
         Member<WebSocketChannelSyncHelper> m_syncHelper;
     };
 
     // Bridge for Peer. Running on the worker thread.
     class Bridge final : public GarbageCollectedFinalized<Bridge> {
         WTF_MAKE_NONCOPYABLE(Bridge);
     public:
         Bridge(WebSocketChannelClient*, WorkerGlobalScope&);
         ~Bridge();
         // SourceLocation parameter may be shown when the connection fails.
         void initialize(PassOwnPtr<SourceLocation>);
         bool connect(const KURL&, const String& protocol);
         void send(const CString& message);
         void send(const DOMArrayBuffer&, unsigned byteOffset, unsigned byteLength);
         void send(PassRefPtr<BlobDataHandle>);
         void close(int code, const String& reason);
         void fail(const String& reason, MessageLevel, PassOwnPtr<SourceLocation>);
         void disconnect();
 
+        void createPeerOnMainThread(PassOwnPtr<SourceLocation>, WorkerThreadContext*, ExecutionContext*);
+
         // Returns null when |disconnect| has already been called.
         WebSocketChannelClient* client() { return m_client; }
 
         DECLARE_TRACE();
 
     private:
         // Returns false if shutdown event is received before method completion.
         bool waitForMethodCompletion(std::unique_ptr<ExecutionContextTask>);
 
         Member<WebSocketChannelClient> m_client;
         Member<WorkerGlobalScope> m_workerGlobalScope;
         RefPtr<WorkerLoaderProxy> m_loaderProxy;
         Member<WebSocketChannelSyncHelper> m_syncHelper;
-        Member<Peer> m_peer;
+        CrossThreadPersistent<Peer> m_peer;
     };
 
 private:
     WorkerWebSocketChannel(WorkerGlobalScope&, WebSocketChannelClient*, PassOwnPtr<SourceLocation>);
 
     Member<Bridge> m_bridge;
     OwnPtr<SourceLocation> m_locationAtConnection;
 };
 
 } // namespace blink
 
 #endif // WorkerWebSocketChannel_h