88 lines
2.9 KiB
C++
88 lines
2.9 KiB
C++
|
// (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
|
||
|
|
// (C) Copyright 2003-2007 Jonathan Turkanis
|
||
|
|
// 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/iostreams for documentation.
|
||
|
|
|
||
|
|
// Contains the definition of the class template access_control, which
|
||
|
|
// allows the type of inheritance from a provided base class to be specified
|
||
|
|
// using a template parameter.
|
||
|
|
|
||
|
|
|
||
|
|
#ifndef BOOST_IOSTREAMS_ACCESS_CONTROL_HPP_INCLUDED
|
||
|
|
#define BOOST_IOSTREAMS_ACCESS_CONTROL_HPP_INCLUDED
|
||
|
|
|
||
|
|
#if defined(_MSC_VER)
|
||
|
|
# pragma once
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#include <boost/iostreams/detail/select.hpp>
|
||
|
|
#include <boost/mpl/identity.hpp>
|
||
|
|
#include <boost/type_traits/is_same.hpp>
|
||
|
|
|
||
|
|
namespace boost { namespace iostreams {
|
||
|
|
|
||
|
|
struct protected_ { }; // Represents protected inheritance.
|
||
|
|
struct public_ { }; // Represents public inheritance.
|
||
|
|
|
||
|
|
|
||
|
|
namespace detail {
|
||
|
|
|
||
|
|
// Implements protected inheritance.
|
||
|
|
template<typename U>
|
||
|
|
struct prot_ : protected U
|
||
|
|
{
|
||
|
|
prot_() { }
|
||
|
|
template<typename V> prot_(V v) : U(v) { }
|
||
|
|
};
|
||
|
|
|
||
|
|
// Implements public inheritance.
|
||
|
|
template<typename U> struct pub_ : public U {
|
||
|
|
pub_() { }
|
||
|
|
template<typename V> pub_(V v) : U(v) { }
|
||
|
|
};
|
||
|
|
|
||
|
|
//
|
||
|
|
// Used to deduce the base type for the template access_control.
|
||
|
|
//
|
||
|
|
template<typename T, typename Access>
|
||
|
|
struct access_control_base {
|
||
|
|
typedef int bad_access_specifier;
|
||
|
|
typedef typename
|
||
|
|
iostreams::select< // Disambiguation for Tru64
|
||
|
|
::boost::is_same<
|
||
|
|
Access, protected_
|
||
|
|
>, prot_<T>,
|
||
|
|
::boost::is_same<
|
||
|
|
Access, public_
|
||
|
|
>, pub_<T>,
|
||
|
|
else_, bad_access_specifier
|
||
|
|
>::type type;
|
||
|
|
};
|
||
|
|
|
||
|
|
} // End namespace detail.
|
||
|
|
|
||
|
|
//
|
||
|
|
// Template name: access_control.
|
||
|
|
// Description: Allows the type of inheritance from a provided base class
|
||
|
|
// to be specified using an int template parameter.
|
||
|
|
// Template parameters:
|
||
|
|
// Base - The class from which to inherit (indirectly.)
|
||
|
|
// Access - The type of access desired. Must be one of the
|
||
|
|
// values access_base::prot or access_base::pub.
|
||
|
|
//
|
||
|
|
template< typename T, typename Access,
|
||
|
|
typename Base = // VC6 workaraound (Compiler Error C2516)
|
||
|
|
typename detail::access_control_base<T, Access>::type >
|
||
|
|
struct access_control : public Base {
|
||
|
|
access_control() { }
|
||
|
|
template<typename U> explicit access_control(U u) : Base(u) { }
|
||
|
|
};
|
||
|
|
|
||
|
|
//----------------------------------------------------------------------------//
|
||
|
|
|
||
|
|
} } // End namespaces iostreams, boost.
|
||
|
|
|
||
|
|
#endif // #ifndef BOOST_IOSTREAMS_ACCESS_CONTROL_HPP_INCLUDED
|