Source/bindings/v8/WorkerScriptController.h

/*
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 * modification, are permitted provided that the following conditions are
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 *
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 * notice, this list of conditions and the following disclaimer.
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 * in the documentation and/or other materials provided with the
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#ifndef WorkerScriptController_h
#define WorkerScriptController_h

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

namespace WebCore {

    class ScriptSourceCode;
    class ScriptValue;
    class WorkerGlobalScope;

    struct WorkerGlobalScopeExecutionState {
        WorkerGlobalScopeExecutionState()
            : hadException(false)
            , lineNumber(0)
            , columnNumber(0)
        {
        }

        bool hadException;
        String errorMessage;
        int lineNumber;
        int columnNumber;
        String sourceURL;
        ScriptValue exception;
    };

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

        WorkerGlobalScope& workerGlobalScope() { return m_workerGlobalScope; }

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

        void rethrowExceptionFromImportedScript(PassRefPtr<ErrorEvent>);

        // 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&);

        // Returns WorkerScriptController for the currently executing context. 0 will be returned if the current executing context is not the worker context.
        static WorkerScriptController* controllerForContext();

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

        // Returns a local handle of the context.
        v8::Local<v8::Context> context() { return m_context.newLocal(m_isolate); }

        // 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 v8::V8::IdleNotification(); }

        v8::Isolate* isolate() const { return m_isolate; }

    private:
        bool initializeContextIfNeeded();
        void disposeContext();

        WorkerGlobalScope& m_workerGlobalScope;
        v8::Isolate* m_isolate;
        ScopedPersistent<v8::Context> m_context;
        OwnPtr<V8PerContextData> m_perContextData;
        String m_disableEvalPending;
        OwnPtr<DOMDataStore> m_domDataStore;
        bool m_executionForbidden;
        bool m_executionScheduledToTerminate;
        mutable Mutex m_scheduledTerminationMutex;
        RefPtr<ErrorEvent> m_errorEventFromImportedScript;
    };

} // namespace WebCore

#endif // WorkerScriptController_h