/*

 * Copyright (C) 2010 Google Inc. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. 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.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''

 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS

 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF

 * THE POSSIBILITY OF SUCH DAMAGE.

 */

#ifndef JSMainThreadExecState_h

#define JSMainThreadExecState_h

#include <JSDOMBinding.h>

#ifndef NDEBUG

#include <wtf/MainThread.h>

#endif

#include <wtf/Noncopyable.h>

namespace WebCore {

class JSMainThreadExecState : public Noncopyable {

public:

    static JSC::ExecState* currentState()

    { 

        ASSERT(WTF::isMainThread());

        return s_mainThreadState;

    };

    static JSC::JSValue call(JSC::ExecState* exec, JSC::JSValue functionObject, JSC::CallType callType, const JSC::CallData& callData, JSC::JSValue thisValue, const JSC::ArgList& args)

    {

        JSMainThreadExecState currentState(exec);

        return JSC::call(exec, functionObject, callType, callData, thisValue, args);

    };

    static JSC::Completion evaluate(JSC::ExecState* exec, JSC::ScopeChain& chain, const JSC::SourceCode& source, JSC::JSValue thisValue)

    {

        JSMainThreadExecState currentState(exec);

        return JSC::evaluate(exec, chain, source, thisValue);

    };

protected:

    explicit JSMainThreadExecState(JSC::ExecState* exec)

        : m_previousState(s_mainThreadState)

    {

        ASSERT(WTF::isMainThread());

        s_mainThreadState = exec;

    };

    ~JSMainThreadExecState()

    {

        ASSERT(WTF::isMainThread());

        s_mainThreadState = m_previousState;

    }

private:

    static JSC::ExecState* s_mainThreadState;

    JSC::ExecState* m_previousState;

};

// Null state prevents origin security checks.

class JSMainThreadNullState : private JSMainThreadExecState {

public:

    explicit JSMainThreadNullState() : JSMainThreadExecState(0) {};

};

} // namespace WebCore

#endif // JSMainThreadExecState_h