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 WorkerScriptController_h
32#define WorkerScriptController_h
33
34#if ENABLE(WORKERS)
35
36#include <wtf/OwnPtr.h>
37#include <wtf/Threading.h>
38
39namespace WebCore {
40
41    class ScriptSourceCode;
42    class ScriptValue;
43    class WorkerContext;
44    class WorkerContextExecutionProxy;
45
46    class WorkerScriptController {
47    public:
48        WorkerScriptController(WorkerContext*);
49        ~WorkerScriptController();
50
51        WorkerContextExecutionProxy* proxy() { return m_proxy.get(); }
52        WorkerContext* workerContext() { return m_workerContext; }
53
54        ScriptValue evaluate(const ScriptSourceCode&);
55        ScriptValue evaluate(const ScriptSourceCode&, ScriptValue* exception);
56
57        void setException(ScriptValue);
58
59        // Async request to terminate a future JS execution. Eventually causes termination
60        // exception raised during JS execution, if the worker thread happens to run JS.
61        // After JS execution was terminated in this way, the Worker thread has to use
62        // forbidExecution()/isExecutionForbidden() to guard against reentry into JS.
63        // Can be called from any thread.
64        void scheduleExecutionTermination();
65
66        // Called on Worker thread when JS exits with termination exception caused by forbidExecution() request,
67        // or by Worker thread termination code to prevent future entry into JS.
68        void forbidExecution();
69        bool isExecutionForbidden() const;
70
71        // Returns WorkerScriptController for the currently executing context. 0 will be returned if the current executing context is not the worker context.
72        static WorkerScriptController* controllerForContext();
73
74    private:
75        WorkerContext* m_workerContext;
76        OwnPtr<WorkerContextExecutionProxy> m_proxy;
77        bool m_executionForbidden;
78    };
79
80} // namespace WebCore
81
82#endif // ENABLE(WORKERS)
83
84#endif // WorkerScriptController_h
85