pointer_type.hpp

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//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2005-2008.
// (C) Copyright Gennaro Prota 2003 - 2004.
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/libs/interprocess for documentation.
//
//////////////////////////////////////////////////////////////////////////////

#ifndef BOOST_INTERPROCESS_DETAIL_POINTER_TYPE_HPP
#define BOOST_INTERPROCESS_DETAIL_POINTER_TYPE_HPP

#if (defined _MSC_VER) && (_MSC_VER >= 1200)
#  pragma once
#endif

#include <boost/interprocess/detail/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
#include <boost/interprocess/detail/type_traits.hpp>

namespace boost {
namespace interprocess {
namespace detail {

struct two {char _[2];};

namespace pointer_type_imp {

template <class U> static two  test(...);
template <class U> static char test(typename U::pointer* = 0);

}  //namespace pointer_type_imp {

template <class T>
struct has_pointer_type
{
    static const bool value = sizeof(pointer_type_imp::test<T>(0)) == 1;
};

namespace pointer_type_imp {

template <class T, class D, bool = has_pointer_type<D>::value>
struct pointer_type
{
    typedef typename D::pointer type;
};

template <class T, class D>
struct pointer_type<T, D, false>
{
    typedef T* type;
};

}  //namespace pointer_type_imp {

template <class T, class D>
struct pointer_type
{
    typedef typename pointer_type_imp::pointer_type<T,
        typename detail::remove_reference<D>::type>::type type;
};

}  //namespace detail {
}  //namespace interprocess { 
}  //namespace boost {

#include <boost/interprocess/detail/config_end.hpp>

#endif   //#ifndef BOOST_INTERPROCESS_DETAIL_POINTER_TYPE_HPP