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 WorkerRunLoop_h
32#define WorkerRunLoop_h
33
34#if ENABLE(WORKERS)
35
36#include "ScriptExecutionContext.h"
37#include <wtf/MessageQueue.h>
38#include <wtf/OwnPtr.h>
39#include <wtf/PassOwnPtr.h>
40
41namespace WebCore {
42
43    class ModePredicate;
44    class WorkerContext;
45    class WorkerSharedTimer;
46
47    class WorkerRunLoop {
48    public:
49        WorkerRunLoop();
50        ~WorkerRunLoop();
51
52        // Blocking call. Waits for tasks and timers, invokes the callbacks.
53        void run(WorkerContext*);
54
55        enum WaitMode { WaitForMessage, DontWaitForMessage };
56
57        // Waits for a single task and returns.
58        MessageQueueWaitResult runInMode(WorkerContext*, const String& mode, WaitMode = WaitForMessage);
59
60        void terminate();
61        bool terminated() const { return m_messageQueue.killed(); }
62
63        void postTask(PassOwnPtr<ScriptExecutionContext::Task>);
64        void postTaskAndTerminate(PassOwnPtr<ScriptExecutionContext::Task>);
65        void postTaskForMode(PassOwnPtr<ScriptExecutionContext::Task>, const String& mode);
66
67        unsigned long createUniqueId() { return ++m_uniqueId; }
68
69        static String defaultMode();
70
71        class Task {
72            WTF_MAKE_NONCOPYABLE(Task); WTF_MAKE_FAST_ALLOCATED;
73        public:
74            static PassOwnPtr<Task> create(PassOwnPtr<ScriptExecutionContext::Task> task, const String& mode);
75            ~Task() { }
76            const String& mode() const { return m_mode; }
77            void performTask(const WorkerRunLoop&, ScriptExecutionContext*);
78
79        private:
80            Task(PassOwnPtr<ScriptExecutionContext::Task> task, const String& mode);
81
82            OwnPtr<ScriptExecutionContext::Task> m_task;
83            String m_mode;
84        };
85
86    private:
87        friend class RunLoopSetup;
88        MessageQueueWaitResult runInMode(WorkerContext*, const ModePredicate&, WaitMode);
89
90        // Runs any clean up tasks that are currently in the queue and returns.
91        // This should only be called when the context is closed or loop has been terminated.
92        void runCleanupTasks(WorkerContext*);
93
94        MessageQueue<Task> m_messageQueue;
95        OwnPtr<WorkerSharedTimer> m_sharedTimer;
96        int m_nestedCount;
97        unsigned long m_uniqueId;
98    };
99
100} // namespace WebCore
101
102#endif // ENABLE(WORKERS)
103
104#endif // WorkerRunLoop_h
105