1 /* 2 * Copyright (C) 2009 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef WorkerThreadableLoader_h 32 #define WorkerThreadableLoader_h 33 34 #if ENABLE(WORKERS) 35 36 #include "PlatformString.h" 37 #include "ThreadableLoader.h" 38 #include "ThreadableLoaderClient.h" 39 #include "ThreadableLoaderClientWrapper.h" 40 41 #include <memory> 42 #include <wtf/PassRefPtr.h> 43 #include <wtf/RefCounted.h> 44 #include <wtf/RefPtr.h> 45 #include <wtf/Threading.h> 46 47 namespace WebCore { 48 49 class ResourceError; 50 class ResourceRequest; 51 class WorkerContext; 52 class WorkerLoaderProxy; 53 struct CrossThreadResourceResponseData; 54 struct CrossThreadResourceRequestData; 55 56 class WorkerThreadableLoader : public RefCounted<WorkerThreadableLoader>, public ThreadableLoader { 57 public: 58 static void loadResourceSynchronously(WorkerContext*, const ResourceRequest&, ThreadableLoaderClient&, const ThreadableLoaderOptions&); 59 static PassRefPtr<WorkerThreadableLoader> create(WorkerContext* workerContext, ThreadableLoaderClient* client, const String& taskMode, const ResourceRequest& request, const ThreadableLoaderOptions& options) 60 { 61 return adoptRef(new WorkerThreadableLoader(workerContext, client, taskMode, request, options)); 62 } 63 64 ~WorkerThreadableLoader(); 65 66 virtual void cancel(); 67 68 bool done() const { return m_workerClientWrapper->done(); } 69 70 using RefCounted<WorkerThreadableLoader>::ref; 71 using RefCounted<WorkerThreadableLoader>::deref; 72 73 protected: 74 virtual void refThreadableLoader() { ref(); } 75 virtual void derefThreadableLoader() { deref(); } 76 77 private: 78 // Creates a loader on the main thread and bridges communication between 79 // the main thread and the worker context's thread where WorkerThreadableLoader runs. 80 // 81 // Regarding the bridge and lifetimes of items used in callbacks, there are a few cases: 82 // 83 // all cases. All tasks posted from the worker context's thread are ok because 84 // the last task posted always is "mainThreadDestroy", so MainThreadBridge is 85 // around for all tasks that use it on the main thread. 86 // 87 // case 1. worker.terminate is called. 88 // In this case, no more tasks are posted from the worker object's thread to the worker 89 // context's thread -- WorkerContextProxy implementation enforces this. 90 // 91 // case 2. xhr gets aborted and the worker context continues running. 92 // The ThreadableLoaderClientWrapper has the underlying client cleared, so no more calls 93 // go through it. All tasks posted from the worker object's thread to the worker context's 94 // thread do "ThreadableLoaderClientWrapper::ref" (automatically inside of the cross thread copy 95 // done in createCallbackTask), so the ThreadableLoaderClientWrapper instance is there until all 96 // tasks are executed. 97 class MainThreadBridge : public ThreadableLoaderClient { 98 public: 99 // All executed on the worker context's thread. 100 MainThreadBridge(PassRefPtr<ThreadableLoaderClientWrapper>, WorkerLoaderProxy&, const String& taskMode, const ResourceRequest&, const ThreadableLoaderOptions&); 101 void cancel(); 102 void destroy(); 103 104 private: 105 // Executed on the worker context's thread. 106 void clearClientWrapper(); 107 108 // All executed on the main thread. 109 static void mainThreadDestroy(ScriptExecutionContext*, MainThreadBridge*); 110 ~MainThreadBridge(); 111 112 static void mainThreadCreateLoader(ScriptExecutionContext*, MainThreadBridge*, std::auto_ptr<CrossThreadResourceRequestData>, ThreadableLoaderOptions); 113 static void mainThreadCancel(ScriptExecutionContext*, MainThreadBridge*); 114 virtual void didSendData(unsigned long long bytesSent, unsigned long long totalBytesToBeSent); 115 virtual void didReceiveResponse(const ResourceResponse&); 116 virtual void didReceiveData(const char*, int lengthReceived); 117 virtual void didFinishLoading(unsigned long identifier); 118 virtual void didFail(const ResourceError&); 119 virtual void didFailRedirectCheck(); 120 virtual void didReceiveAuthenticationCancellation(const ResourceResponse&); 121 122 // Only to be used on the main thread. 123 RefPtr<ThreadableLoader> m_mainThreadLoader; 124 125 // ThreadableLoaderClientWrapper is to be used on the worker context thread. 126 // The ref counting is done on either thread. 127 RefPtr<ThreadableLoaderClientWrapper> m_workerClientWrapper; 128 129 // May be used on either thread. 130 WorkerLoaderProxy& m_loaderProxy; 131 132 // For use on the main thread. 133 String m_taskMode; 134 }; 135 136 WorkerThreadableLoader(WorkerContext*, ThreadableLoaderClient*, const String& taskMode, const ResourceRequest&, const ThreadableLoaderOptions&); 137 138 RefPtr<WorkerContext> m_workerContext; 139 RefPtr<ThreadableLoaderClientWrapper> m_workerClientWrapper; 140 MainThreadBridge& m_bridge; 141 }; 142 143 } // namespace WebCore 144 145 #endif // ENABLE(WORKERS) 146 147 #endif // WorkerThreadableLoader_h 148