1 /*
2  * Copyright (C) 2008 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 COMPUTER, INC. ``AS IS'' AND ANY
14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  */
26 
27 #ifndef WorkerScriptController_h
28 #define WorkerScriptController_h
29 
30 #if ENABLE(WORKERS)
31 
32 #include <heap/Strong.h>
33 #include <wtf/Forward.h>
34 #include <wtf/Threading.h>
35 
36 namespace JSC {
37     class JSGlobalData;
38 }
39 
40 namespace WebCore {
41 
42     class JSWorkerContext;
43     class ScriptSourceCode;
44     class ScriptValue;
45     class WorkerContext;
46 
47     class WorkerScriptController {
48         WTF_MAKE_NONCOPYABLE(WorkerScriptController); WTF_MAKE_FAST_ALLOCATED;
49     public:
50         WorkerScriptController(WorkerContext*);
51         ~WorkerScriptController();
52 
workerContextWrapper()53         JSWorkerContext* workerContextWrapper()
54         {
55             initScriptIfNeeded();
56             return m_workerContextWrapper.get();
57         }
58 
59         ScriptValue evaluate(const ScriptSourceCode&);
60         ScriptValue evaluate(const ScriptSourceCode&, ScriptValue* exception);
61 
62         void setException(ScriptValue);
63 
64         // Async request to terminate a JS run execution. Eventually causes termination
65         // exception raised during JS execution, if the worker thread happens to run JS.
66         // After JS execution was terminated in this way, the Worker thread has to use
67         // forbidExecution()/isExecutionForbidden() to guard against reentry into JS.
68         // Can be called from any thread.
69         void scheduleExecutionTermination();
70 
71         // Called on Worker thread when JS exits with termination exception caused by forbidExecution() request,
72         // or by Worker thread termination code to prevent future entry into JS.
73         void forbidExecution();
74         bool isExecutionForbidden() const;
75 
globalData()76         JSC::JSGlobalData* globalData() { return m_globalData.get(); }
77 
78     private:
initScriptIfNeeded()79         void initScriptIfNeeded()
80         {
81             if (!m_workerContextWrapper)
82                 initScript();
83         }
84         void initScript();
85 
86         RefPtr<JSC::JSGlobalData> m_globalData;
87         WorkerContext* m_workerContext;
88         JSC::Strong<JSWorkerContext> m_workerContextWrapper;
89         bool m_executionForbidden;
90     };
91 
92 } // namespace WebCore
93 
94 #endif // ENABLE(WORKERS)
95 
96 #endif // WorkerScriptController_h
97