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 * modification, are permitted provided that the following conditions are
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 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * 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.
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
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 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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#ifndef WorkerScriptController_h
#define WorkerScriptController_h

#include "bindings/core/v8/ScriptValue.h"
#include "bindings/core/v8/V8Binding.h"
#include "wtf/OwnPtr.h"
#include "wtf/ThreadingPrimitives.h"
#include "wtf/text/TextPosition.h"
#include <v8.h>

namespace blink {

class ErrorEvent;
class ExceptionState;
class ScriptSourceCode;
class ScriptValue;
class WorkerGlobalScope;
class WorkerGlobalScopeExecutionState;

class WorkerScriptController {
public:
    explicit WorkerScriptController(WorkerGlobalScope&);
    ~WorkerScriptController();

    WorkerGlobalScope& workerGlobalScope() { return m_workerGlobalScope; }

    bool initializeContextIfNeeded();

    void evaluate(const ScriptSourceCode&, RefPtrWillBeRawPtr<ErrorEvent>* = 0);

    void rethrowExceptionFromImportedScript(PassRefPtrWillBeRawPtr<ErrorEvent>, ExceptionState&);

    // Async request to terminate a future JS execution. Eventually causes termination
    // exception raised during JS execution, if the worker thread happens to run JS.
    // After JS execution was terminated in this way, the Worker thread has to use
    // forbidExecution()/isExecutionForbidden() to guard against reentry into JS.
    // Can be called from any thread.
    void scheduleExecutionTermination();
    bool isExecutionTerminating() const;

    // Called on Worker thread when JS exits with termination exception caused by forbidExecution() request,
    // or by Worker thread termination code to prevent future entry into JS.
    void forbidExecution();
    bool isExecutionForbidden() const;

    void disableEval(const String&);

    v8::Isolate* isolate() const { return m_isolate; }
    DOMWrapperWorld& world() const { return *m_world; }
    ScriptState* scriptState() { return m_scriptState.get(); }
    v8::Local<v8::Context> context() { return m_scriptState ? m_scriptState->context() : v8::Local<v8::Context>(); }
    bool isContextInitialized() { return m_scriptState && !!m_scriptState->perContextData(); }

    // Send a notification about current thread is going to be idle.
    // Returns true if the embedder should stop calling idleNotification
    // until real work has been done.
    bool idleNotification() { return m_isolate->IdleNotification(1000); }

private:
    class WorkerGlobalScopeExecutionState;

    // Evaluate a script file in the current execution environment.
    ScriptValue evaluate(const String& script, const String& fileName, const TextPosition& scriptStartPosition);

    v8::Isolate* m_isolate;
    WorkerGlobalScope& m_workerGlobalScope;
    RefPtr<ScriptState> m_scriptState;
    RefPtr<DOMWrapperWorld> m_world;
    String m_disableEvalPending;
    bool m_executionForbidden;
    bool m_executionScheduledToTerminate;
    mutable Mutex m_scheduledTerminationMutex;

    // |m_globalScopeExecutionState| refers to a stack object
    // that evaluate() allocates; evaluate() ensuring that the
    // pointer reference to it is removed upon returning. Hence
    // kept as a bare pointer here, and not a Persistent with
    // Oilpan enabled; stack scanning will visit the object and
    // trace its on-heap fields.
    GC_PLUGIN_IGNORE("394615")
    WorkerGlobalScopeExecutionState* m_globalScopeExecutionState;
    OwnPtr<V8IsolateInterruptor> m_interruptor;
};

} // namespace blink

#endif // WorkerScriptController_h
