+++ /dev/null
-/*
- * Copyright (C) 2008 Apple Inc. All rights reserved.
- * Copyright (C) 2009 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
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
- * its contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, 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 MessageQueue_h
-#define MessageQueue_h
-
-#include <limits>
-#include <wtf/Assertions.h>
-#include <wtf/Deque.h>
-#include <wtf/Noncopyable.h>
-#include <wtf/Threading.h>
-
-namespace WTF {
-
- enum MessageQueueWaitResult {
- MessageQueueTerminated, // Queue was destroyed while waiting for message.
- MessageQueueTimeout, // Timeout was specified and it expired.
- MessageQueueMessageReceived // A message was successfully received and returned.
- };
-
- // The queue takes ownership of messages and transfer it to the new owner
- // when messages are fetched from the queue.
- // Essentially, MessageQueue acts as a queue of OwnPtr<DataType>.
- template<typename DataType>
- class MessageQueue {
- WTF_MAKE_NONCOPYABLE(MessageQueue);
- public:
- MessageQueue() : m_killed(false) { }
- ~MessageQueue();
-
- void append(PassOwnPtr<DataType>);
- bool appendAndCheckEmpty(PassOwnPtr<DataType>);
- void prepend(PassOwnPtr<DataType>);
-
- PassOwnPtr<DataType> waitForMessage();
- PassOwnPtr<DataType> tryGetMessage();
- template<typename Predicate>
- PassOwnPtr<DataType> waitForMessageFilteredWithTimeout(MessageQueueWaitResult&, Predicate&, double absoluteTime);
-
- template<typename Predicate>
- void removeIf(Predicate&);
-
- void kill();
- bool killed() const;
-
- // The result of isEmpty() is only valid if no other thread is manipulating the queue at the same time.
- bool isEmpty();
-
- static double infiniteTime() { return std::numeric_limits<double>::max(); }
-
- private:
- static bool alwaysTruePredicate(DataType*) { return true; }
-
- mutable Mutex m_mutex;
- ThreadCondition m_condition;
- Deque<DataType*> m_queue;
- bool m_killed;
- };
-
- template<typename DataType>
- MessageQueue<DataType>::~MessageQueue()
- {
- deleteAllValues(m_queue);
- }
-
- template<typename DataType>
- inline void MessageQueue<DataType>::append(PassOwnPtr<DataType> message)
- {
- MutexLocker lock(m_mutex);
- m_queue.append(message.leakPtr());
- m_condition.signal();
- }
-
- // Returns true if the queue was empty before the item was added.
- template<typename DataType>
- inline bool MessageQueue<DataType>::appendAndCheckEmpty(PassOwnPtr<DataType> message)
- {
- MutexLocker lock(m_mutex);
- bool wasEmpty = m_queue.isEmpty();
- m_queue.append(message.leakPtr());
- m_condition.signal();
- return wasEmpty;
- }
-
- template<typename DataType>
- inline void MessageQueue<DataType>::prepend(PassOwnPtr<DataType> message)
- {
- MutexLocker lock(m_mutex);
- m_queue.prepend(message.leakPtr());
- m_condition.signal();
- }
-
- template<typename DataType>
- inline PassOwnPtr<DataType> MessageQueue<DataType>::waitForMessage()
- {
- MessageQueueWaitResult exitReason;
- OwnPtr<DataType> result = waitForMessageFilteredWithTimeout(exitReason, MessageQueue<DataType>::alwaysTruePredicate, infiniteTime());
- ASSERT(exitReason == MessageQueueTerminated || exitReason == MessageQueueMessageReceived);
- return result.release();
- }
-
- template<typename DataType>
- template<typename Predicate>
- inline PassOwnPtr<DataType> MessageQueue<DataType>::waitForMessageFilteredWithTimeout(MessageQueueWaitResult& result, Predicate& predicate, double absoluteTime)
- {
- MutexLocker lock(m_mutex);
- bool timedOut = false;
-
- DequeConstIterator<DataType*> found = m_queue.end();
- while (!m_killed && !timedOut && (found = m_queue.findIf(predicate)) == m_queue.end())
- timedOut = !m_condition.timedWait(m_mutex, absoluteTime);
-
- ASSERT(!timedOut || absoluteTime != infiniteTime());
-
- if (m_killed) {
- result = MessageQueueTerminated;
- return nullptr;
- }
-
- if (timedOut) {
- result = MessageQueueTimeout;
- return nullptr;
- }
-
- ASSERT(found != m_queue.end());
- OwnPtr<DataType> message = adoptPtr(*found);
- m_queue.remove(found);
- result = MessageQueueMessageReceived;
- return message.release();
- }
-
- template<typename DataType>
- inline PassOwnPtr<DataType> MessageQueue<DataType>::tryGetMessage()
- {
- MutexLocker lock(m_mutex);
- if (m_killed)
- return nullptr;
- if (m_queue.isEmpty())
- return nullptr;
-
- return adoptPtr(m_queue.takeFirst());
- }
-
- template<typename DataType>
- template<typename Predicate>
- inline void MessageQueue<DataType>::removeIf(Predicate& predicate)
- {
- MutexLocker lock(m_mutex);
- // See bug 31657 for why this loop looks so weird
- while (true) {
- DequeConstIterator<DataType*> found = m_queue.findIf(predicate);
- if (found == m_queue.end())
- break;
-
- DataType* message = *found;
- m_queue.remove(found);
- delete message;
- }
- }
-
- template<typename DataType>
- inline bool MessageQueue<DataType>::isEmpty()
- {
- MutexLocker lock(m_mutex);
- if (m_killed)
- return true;
- return m_queue.isEmpty();
- }
-
- template<typename DataType>
- inline void MessageQueue<DataType>::kill()
- {
- MutexLocker lock(m_mutex);
- m_killed = true;
- m_condition.broadcast();
- }
-
- template<typename DataType>
- inline bool MessageQueue<DataType>::killed() const
- {
- MutexLocker lock(m_mutex);
- return m_killed;
- }
-} // namespace WTF
-
-using WTF::MessageQueue;
-// MessageQueueWaitResult enum and all its values.
-using WTF::MessageQueueWaitResult;
-using WTF::MessageQueueTerminated;
-using WTF::MessageQueueTimeout;
-using WTF::MessageQueueMessageReceived;
-
-#endif // MessageQueue_h
projects / apple / javascriptcore.git / blobdiff