WebSocket: Consolidate inter-thread synchronous function calls

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

 /*
  * Copyright (C) 2011, 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:
  *
  *     * 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 91 matching lines @@
     }
 
     std::unique_ptr<WaitableEvent> m_event;
     bool m_connectRequestResult;
 };
 
 WorkerWebSocketChannel::WorkerWebSocketChannel(WorkerGlobalScope& workerGlobalScope, WebSocketChannelClient* client, std::unique_ptr<SourceLocation> location)
     : m_bridge(new Bridge(client, workerGlobalScope))
     , m_locationAtConnection(std::move(location))
 {
-    m_bridge->initialize(m_locationAtConnection->clone());
 }
 
 WorkerWebSocketChannel::~WorkerWebSocketChannel()
 {
     ASSERT(!m_bridge);
 }
 
 bool WorkerWebSocketChannel::connect(const KURL& url, const String& protocol)
 {
     ASSERT(m_bridge);
-    return m_bridge->connect(url, protocol);
+    return m_bridge->connect(m_locationAtConnection->clone(), url, protocol);
 }
 
 void WorkerWebSocketChannel::send(const CString& message)
 {
     ASSERT(m_bridge);
     m_bridge->send(message);
 }
 
 void WorkerWebSocketChannel::send(const DOMArrayBuffer& binaryData, unsigned byteOffset, unsigned byteLength)
 {
@@ skipping 63 matching lines @@
 bool Peer::initialize(std::unique_ptr<SourceLocation> location, ExecutionContext* context)
 {
     ASSERT(isMainThread());
     if (wasContextDestroyedBeforeObserverCreation())
         return false;
     Document* document = toDocument(context);
     m_mainWebSocketChannel = DocumentWebSocketChannel::create(document, this, std::move(location));
     return true;
 }
 
 void Peer::connect(const KURL& url, const String& protocol)

[yhirano, 2016/08/24 04:46:32]

How about making this function return a boolean instead of set the result to
m_syncHelper?

[nhiroki, 2016/08/24 04:58:03]

Done.

 {
     ASSERT(isMainThread());
     ASSERT(m_syncHelper);
     if (!m_mainWebSocketChannel) {
         m_syncHelper->setConnectRequestResult(false);
     } else {
         bool connectRequestResult = m_mainWebSocketChannel->connect(url, protocol);
         m_syncHelper->setConnectRequestResult(connectRequestResult);
     }
-    m_syncHelper->signalWorkerThread();
 }
 
 void Peer::sendTextAsCharVector(std::unique_ptr<Vector<char>> data)
 {
     ASSERT(isMainThread());
     if (m_mainWebSocketChannel)
         m_mainWebSocketChannel->sendTextAsCharVector(std::move(data));
 }
 
 void Peer::sendBinaryAsCharVector(std::unique_ptr<Vector<char>> data)
@@ skipping 158 matching lines @@
     , m_loaderProxy(m_workerGlobalScope->thread()->workerLoaderProxy())
     , m_syncHelper(WebSocketChannelSyncHelper::create(wrapUnique(new WaitableEvent())))
 {
 }
 
 Bridge::~Bridge()
 {
     ASSERT(!m_peer);
 }
 
-void Bridge::createPeerOnMainThread(std::unique_ptr<SourceLocation> location, WorkerThreadLifecycleContext* workerThreadLifecycleContext, ExecutionContext* context)
+void Bridge::connectOnMainThread(std::unique_ptr<SourceLocation> location, WorkerThreadLifecycleContext* workerThreadLifecycleContext, const KURL& url, const String& protocol, ExecutionContext* context)
 {
     DCHECK(isMainThread());
     DCHECK(!m_peer);
     Peer* peer = new Peer(this, m_loaderProxy, m_syncHelper, workerThreadLifecycleContext);
-    if (peer->initialize(std::move(location), context))
+    if (peer->initialize(std::move(location), context)) {
         m_peer = peer;
+        m_peer->connect(url, protocol);
+    }
     m_syncHelper->signalWorkerThread();
 }
 
-void Bridge::initialize(std::unique_ptr<SourceLocation> location)
+bool Bridge::connect(std::unique_ptr<SourceLocation> location, const KURL& url, const String& protocol)
 {
-    // Wait for completion of the task on the main thread because the connection
-    // must synchronously be established (see Bridge::connect).
-    if (!waitForMethodCompletion(BLINK_FROM_HERE, createCrossThreadTask(&Bridge::createPeerOnMainThread, wrapCrossThreadPersistent(this), passed(location->clone()), wrapCrossThreadPersistent(m_workerGlobalScope->thread()->getWorkerThreadLifecycleContext())))) {
-        // The worker thread has been signalled to shutdown before method completion.
-        disconnect();
-    }
-}
-
-bool Bridge::connect(const KURL& url, const String& protocol)
-{
-    if (!m_peer)
-        return false;
-
     // Wait for completion of the task on the main thread because the mixed
     // content check must synchronously be conducted.
-    if (!waitForMethodCompletion(BLINK_FROM_HERE, createCrossThreadTask(&Peer::connect, wrapCrossThreadPersistent(m_peer.get()), url, protocol)))
+    if (!waitForMethodCompletion(BLINK_FROM_HERE, createCrossThreadTask(&Bridge::connectOnMainThread, wrapCrossThreadPersistent(this), passed(location->clone()), wrapCrossThreadPersistent(m_workerGlobalScope->thread()->getWorkerThreadLifecycleContext()), url, protocol)))
         return false;
 
     return m_syncHelper->connectRequestResult();
 }
 
 void Bridge::send(const CString& message)
 {
     ASSERT(m_peer);
     std::unique_ptr<Vector<char>> data = wrapUnique(new Vector<char>(message.length()));
     if (message.length())
@@ skipping 65 matching lines @@
 }
 
 DEFINE_TRACE(Bridge)
 {
     visitor->trace(m_client);
     visitor->trace(m_workerGlobalScope);
     visitor->trace(m_syncHelper);
 }
 
 } // namespace blink