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// (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.
#ifndef BOOST_IOSTREAMS_OPTIMAL_BUFFER_SIZE_HPP_INCLUDED
#define BOOST_IOSTREAMS_OPTIMAL_BUFFER_SIZE_HPP_INCLUDED
#if defined(_MSC_VER)
# pragma once
#endif
#include <boost/config.hpp> // DEDUCED_TYPENAME, MSVC.
#include <boost/detail/workaround.hpp>
#include <boost/iostreams/constants.hpp> // constants.
#include <boost/iostreams/detail/dispatch.hpp>
#include <boost/iostreams/detail/wrap_unwrap.hpp>
#include <boost/iostreams/operations_fwd.hpp>
#include <boost/mpl/if.hpp>
// Must come last.
#include <boost/iostreams/detail/config/disable_warnings.hpp>
namespace boost { namespace iostreams {
namespace detail {
template<typename T>
struct optimal_buffer_size_impl;
} // End namespace detail.
template<typename T>
std::streamsize optimal_buffer_size(const T& t)
{
typedef detail::optimal_buffer_size_impl<T> impl;
return impl::optimal_buffer_size(detail::unwrap(t));
}
namespace detail {
//------------------Definition of optimal_buffer_size_impl--------------------//
template<typename T>
struct optimal_buffer_size_impl
: mpl::if_<
is_custom<T>,
operations<T>,
optimal_buffer_size_impl<
BOOST_DEDUCED_TYPENAME
dispatch<
T, optimally_buffered_tag, device_tag, filter_tag
>::type
>
>::type
{ };
template<>
struct optimal_buffer_size_impl<optimally_buffered_tag> {
template<typename T>
static std::streamsize optimal_buffer_size(const T& t)
{ return t.optimal_buffer_size(); }
};
template<>
struct optimal_buffer_size_impl<device_tag> {
template<typename T>
static std::streamsize optimal_buffer_size(const T&)
{ return default_device_buffer_size; }
};
template<>
struct optimal_buffer_size_impl<filter_tag> {
template<typename T>
static std::streamsize optimal_buffer_size(const T&)
{ return default_filter_buffer_size; }
};
} // End namespace detail.
} } // End namespaces iostreams, boost.
#include <boost/iostreams/detail/config/enable_warnings.hpp>
#endif // #ifndef BOOST_IOSTREAMS_OPTIMAL_BUFFER_SIZE_HPP_INCLUDED