src/third_party/WebKit/Source/JavaScriptCore/heap/HandleTypes.h

/*
 * Copyright (C) 2011 Apple 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 HandleTypes_h
#define HandleTypes_h

#include "JSValue.h"

namespace JSC {

typedef enum { } Unknown;
typedef JSValue* HandleSlot;

template<typename T> struct HandleTypes {
    typedef T* ExternalType;
    static ExternalType getFromSlot(HandleSlot slot) { return (slot && *slot) ? reinterpret_cast<ExternalType>(static_cast<void*>(slot->asCell())) : 0; }
    static JSValue toJSValue(T* cell) { return reinterpret_cast<JSCell*>(cell); }
    template<typename U> static void validateUpcast() { T* temp; temp = (U*)0; }
};

template<> struct HandleTypes<Unknown> {
    typedef JSValue ExternalType;
    static ExternalType getFromSlot(HandleSlot slot) { return slot ? *slot : JSValue(); }
    static JSValue toJSValue(const JSValue& v) { return v; }
    template<typename U> static void validateUpcast() { }
};

} // namespace JSC

#endif // HandleTypes_h