malloczonesupport.h

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/*
 * Copyright (C) 2007 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. 
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE 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 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 MallocZoneSupport_h
#define MallocZoneSupport_h

#include <malloc/malloc.h>

namespace WTF {

class RemoteMemoryReader {
    task_t m_task;
    memory_reader_t* m_reader;

public:
    RemoteMemoryReader(task_t task, memory_reader_t* reader)
        : m_task(task)
        , m_reader(reader)
    { }

    void* operator()(vm_address_t address, size_t size) const
    {
        void* output;
        kern_return_t err = (*m_reader)(m_task, address, size, static_cast<void**>(&output));
        ASSERT(!err);
        if (err)
            output = 0;
        return output;
    }

    template <typename T>
    T* operator()(T* address, size_t size=sizeof(T)) const
    {
        return static_cast<T*>((*this)(reinterpret_cast<vm_address_t>(address), size));
    }
};

} // namespace WTF

#endif // MallocZoneSupport_h