1/* 2 * Copyright (C) 2012 Apple 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 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' 14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS 17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 23 * THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#ifndef BlockingResponseMap_h 27#define BlockingResponseMap_h 28 29#include <wtf/HashMap.h> 30#include <wtf/OwnPtr.h> 31#include <wtf/PassOwnPtr.h> 32#include <wtf/ThreadingPrimitives.h> 33 34template<typename T> 35class BlockingResponseMap { 36WTF_MAKE_NONCOPYABLE(BlockingResponseMap); 37public: 38 BlockingResponseMap() : m_canceled(false) { } 39 ~BlockingResponseMap() { ASSERT(m_responses.isEmpty()); } 40 41 PassOwnPtr<T> waitForResponse(uint64_t requestID) 42 { 43 while (true) { 44 MutexLocker locker(m_mutex); 45 46 if (m_canceled) 47 return nullptr; 48 49 if (OwnPtr<T> response = m_responses.take(requestID)) 50 return response.release(); 51 52 m_condition.wait(m_mutex); 53 } 54 55 return nullptr; 56 } 57 58 void didReceiveResponse(uint64_t requestID, PassOwnPtr<T> response) 59 { 60 MutexLocker locker(m_mutex); 61 ASSERT(!m_responses.contains(requestID)); 62 63 m_responses.set(requestID, response); 64 // FIXME: Waking up all threads is quite inefficient. 65 m_condition.broadcast(); 66 } 67 68 void cancel() 69 { 70 m_canceled = true; 71 72 // FIXME: Waking up all threads is quite inefficient. 73 m_condition.broadcast(); 74 } 75 76private: 77 Mutex m_mutex; 78 ThreadCondition m_condition; 79 80 HashMap<uint64_t, OwnPtr<T>> m_responses; 81 bool m_canceled; 82}; 83 84#endif // BlockingResponseMap_h 85