// (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 metafunctions char_type_of, category_of and mode_of used for | |
// deducing the i/o category and i/o mode of a model of Filter or Device. | |
// | |
// Also contains several utility metafunctions, functions and macros. | |
// | |
#ifndef BOOST_IOSTREAMS_IO_TRAITS_HPP_INCLUDED | |
#define BOOST_IOSTREAMS_IO_TRAITS_HPP_INCLUDED | |
#if defined(_MSC_VER) && (_MSC_VER >= 1020) | |
# pragma once | |
#endif | |
#include <iosfwd> // stream types, char_traits. | |
#include <boost/config.hpp> // partial spec, deduced typename. | |
#include <boost/detail/workaround.hpp> | |
#include <boost/iostreams/categories.hpp> | |
#include <boost/iostreams/detail/bool_trait_def.hpp> | |
#include <boost/iostreams/detail/config/wide_streams.hpp> | |
#include <boost/iostreams/detail/is_iterator_range.hpp> | |
#include <boost/iostreams/detail/select.hpp> | |
#include <boost/iostreams/detail/select_by_size.hpp> | |
#include <boost/iostreams/detail/wrap_unwrap.hpp> | |
#include <boost/iostreams/traits_fwd.hpp> | |
#include <boost/mpl/bool.hpp> | |
#include <boost/mpl/eval_if.hpp> | |
#include <boost/mpl/identity.hpp> | |
#include <boost/mpl/int.hpp> | |
#include <boost/mpl/or.hpp> | |
#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300) | |
# include <boost/range/iterator_range.hpp> | |
# include <boost/range/value_type.hpp> | |
#endif // #if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) | |
#include <boost/ref.hpp> | |
#include <boost/type_traits/is_convertible.hpp> | |
// Must come last. | |
#include <boost/iostreams/detail/config/disable_warnings.hpp> | |
namespace boost { namespace iostreams { | |
//----------Definitions of predicates for streams and stream buffers----------// | |
#ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //--------------------------------// | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_istream, std::basic_istream, 2) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ostream, std::basic_ostream, 2) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_iostream, std::basic_iostream, 2) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_streambuf, std::basic_streambuf, 2) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ifstream, std::basic_ifstream, 2) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ofstream, std::basic_ofstream, 2) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_fstream, std::basic_fstream, 2) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_filebuf, std::basic_filebuf, 2) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_istringstream, std::basic_istringstream, 3) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ostringstream, std::basic_ostringstream, 3) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_stringstream, std::basic_stringstream, 3) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_stringbuf, std::basic_stringbuf, 3) | |
#else // #ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //-----------------------// | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_istream, std::istream, 0) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ostream, std::ostream, 0) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_iostream, std::iostream, 0) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_streambuf, std::streambuf, 0) | |
#endif // #ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //----------------------// | |
template<typename T> | |
struct is_std_io | |
: mpl::or_< is_istream<T>, is_ostream<T>, is_streambuf<T> > | |
{ }; | |
template<typename T> | |
struct is_std_file_device | |
: mpl::or_< | |
is_ifstream<T>, | |
is_ofstream<T>, | |
is_fstream<T>, | |
is_filebuf<T> | |
> | |
{ }; | |
template<typename T> | |
struct is_std_string_device | |
: mpl::or_< | |
is_istringstream<T>, | |
is_ostringstream<T>, | |
is_stringstream<T>, | |
is_stringbuf<T> | |
> | |
{ }; | |
template<typename Device, typename Tr, typename Alloc> | |
struct stream; | |
template<typename T, typename Tr, typename Alloc, typename Mode> | |
class stream_buffer; | |
template< typename Mode, typename Ch, typename Tr, | |
typename Alloc, typename Access > | |
class filtering_stream; | |
template< typename Mode, typename Ch, typename Tr, | |
typename Alloc, typename Access > | |
class wfiltering_stream; | |
template< typename Mode, typename Ch, typename Tr, | |
typename Alloc, typename Access > | |
class filtering_streambuf; | |
template< typename Mode, typename Ch, typename Tr, | |
typename Alloc, typename Access > | |
class filtering_wstreambuf; | |
namespace detail { | |
template<typename T, typename Tr> | |
class linked_streambuf; | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_boost_stream, | |
boost::iostreams::stream, | |
3 ) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_boost_stream_buffer, | |
boost::iostreams::stream_buffer, | |
4 ) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_filtering_stream_impl, | |
boost::iostreams::filtering_stream, | |
5 ) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_filtering_wstream_impl, | |
boost::iostreams::wfiltering_stream, | |
5 ) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_filtering_streambuf_impl, | |
boost::iostreams::filtering_streambuf, | |
5 ) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_filtering_wstreambuf_impl, | |
boost::iostreams::filtering_wstreambuf, | |
5 ) | |
BOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_linked, linked_streambuf, 2) | |
template<typename T> | |
struct is_filtering_stream | |
: mpl::or_< | |
is_filtering_stream_impl<T>, | |
is_filtering_wstream_impl<T> | |
> | |
{ }; | |
template<typename T> | |
struct is_filtering_streambuf | |
: mpl::or_< | |
is_filtering_streambuf_impl<T>, | |
is_filtering_wstreambuf_impl<T> | |
> | |
{ }; | |
template<typename T> | |
struct is_boost | |
: mpl::or_< | |
is_boost_stream<T>, | |
is_boost_stream_buffer<T>, | |
is_filtering_stream<T>, | |
is_filtering_streambuf<T> | |
> | |
{ }; | |
} // End namespace detail. | |
//------------------Definitions of char_type_of-------------------------------// | |
namespace detail { | |
template<typename T> | |
struct member_char_type { typedef typename T::char_type type; }; | |
} // End namespace detail. | |
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //---------------------------// | |
# ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //-------------------------------// | |
template<typename T> | |
struct char_type_of | |
: detail::member_char_type< | |
typename detail::unwrapped_type<T>::type | |
> | |
{ }; | |
# else // # ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //---------------------// | |
template<typename T> | |
struct char_type_of { | |
typedef typename detail::unwrapped_type<T>::type U; | |
typedef typename | |
mpl::eval_if< | |
is_std_io<U>, | |
mpl::identity<char>, | |
detail::member_char_type<U> | |
>::type type; | |
}; | |
# endif // # ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //--------------------// | |
template<typename Iter> | |
struct char_type_of< iterator_range<Iter> > { | |
typedef typename iterator_value<Iter>::type type; | |
}; | |
#else // #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //------------------// | |
template<typename T> | |
struct char_type_of { | |
template<typename U> | |
struct get_value_type { | |
#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300) | |
typedef typename range_value<U>::type type; | |
#endif // #if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) | |
}; | |
typedef typename | |
mpl::eval_if< | |
is_iterator_range<T>, | |
get_value_type<T>, | |
detail::member_char_type< | |
BOOST_DEDUCED_TYPENAME detail::unwrapped_type<T>::type | |
> | |
>::type type; | |
}; | |
#endif // #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //-----------------// | |
//------------------Definitions of category_of--------------------------------// | |
namespace detail { | |
template<typename T> | |
struct member_category { typedef typename T::category type; }; | |
} // End namespace detail. | |
template<typename T> | |
struct category_of { | |
template<typename U> | |
struct member_category { | |
typedef typename U::category type; | |
}; | |
typedef typename detail::unwrapped_type<T>::type U; | |
typedef typename | |
mpl::eval_if< | |
mpl::and_< | |
is_std_io<U>, | |
mpl::not_< detail::is_boost<U> > | |
>, | |
iostreams::select< // Disambiguation for Tru64 | |
is_filebuf<U>, filebuf_tag, | |
is_ifstream<U>, ifstream_tag, | |
is_ofstream<U>, ofstream_tag, | |
is_fstream<U>, fstream_tag, | |
is_stringbuf<U>, stringbuf_tag, | |
is_istringstream<U>, istringstream_tag, | |
is_ostringstream<U>, ostringstream_tag, | |
is_stringstream<U>, stringstream_tag, | |
is_streambuf<U>, generic_streambuf_tag, | |
is_iostream<U>, generic_iostream_tag, | |
is_istream<U>, generic_istream_tag, | |
is_ostream<U>, generic_ostream_tag | |
>, | |
detail::member_category<U> | |
>::type type; | |
}; | |
// Partial specialization for reference wrappers | |
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //---------------------------// | |
template<typename T> | |
struct category_of< reference_wrapper<T> > | |
: category_of<T> | |
{ }; | |
#endif // #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //-----------------// | |
//------------------Definition of get_category--------------------------------// | |
// | |
// Returns an object of type category_of<T>::type. | |
// | |
template<typename T> | |
inline typename category_of<T>::type get_category(const T&) | |
{ typedef typename category_of<T>::type category; return category(); } | |
//------------------Definition of int_type_of---------------------------------// | |
template<typename T> | |
struct int_type_of { | |
#ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES | |
typedef std::char_traits< | |
BOOST_DEDUCED_TYPENAME char_type_of<T>::type | |
> traits_type; | |
typedef typename traits_type::int_type type; | |
#else | |
typedef int type; | |
#endif | |
}; | |
//------------------Definition of mode_of-------------------------------------// | |
namespace detail { | |
template<int N> struct io_mode_impl; | |
#define BOOST_IOSTREAMS_MODE_HELPER(tag_, id_) \ | |
case_<id_> io_mode_impl_helper(tag_); \ | |
template<> struct io_mode_impl<id_> { typedef tag_ type; }; \ | |
/**/ | |
BOOST_IOSTREAMS_MODE_HELPER(input, 1) | |
BOOST_IOSTREAMS_MODE_HELPER(output, 2) | |
BOOST_IOSTREAMS_MODE_HELPER(bidirectional, 3) | |
BOOST_IOSTREAMS_MODE_HELPER(input_seekable, 4) | |
BOOST_IOSTREAMS_MODE_HELPER(output_seekable, 5) | |
BOOST_IOSTREAMS_MODE_HELPER(seekable, 6) | |
BOOST_IOSTREAMS_MODE_HELPER(dual_seekable, 7) | |
BOOST_IOSTREAMS_MODE_HELPER(bidirectional_seekable, 8) | |
BOOST_IOSTREAMS_MODE_HELPER(dual_use, 9) | |
#undef BOOST_IOSTREAMS_MODE_HELPER | |
template<typename T> | |
struct io_mode_id { | |
typedef typename category_of<T>::type category; | |
BOOST_SELECT_BY_SIZE(int, value, detail::io_mode_impl_helper(category())); | |
}; | |
} // End namespace detail. | |
template<typename T> // Borland 5.6.4 requires this circumlocution. | |
struct mode_of : detail::io_mode_impl< detail::io_mode_id<T>::value > { }; | |
// Partial specialization for reference wrappers | |
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //---------------------------// | |
template<typename T> | |
struct mode_of< reference_wrapper<T> > | |
: mode_of<T> | |
{ }; | |
#endif // #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //-----------------// | |
//------------------Definition of is_device, is_filter and is_direct----------// | |
namespace detail { | |
template<typename T, typename Tag> | |
struct has_trait_impl { | |
typedef typename category_of<T>::type category; | |
BOOST_STATIC_CONSTANT(bool, value = (is_convertible<category, Tag>::value)); | |
}; | |
template<typename T, typename Tag> | |
struct has_trait | |
: mpl::bool_<has_trait_impl<T, Tag>::value> | |
{ }; | |
} // End namespace detail. | |
template<typename T> | |
struct is_device : detail::has_trait<T, device_tag> { }; | |
template<typename T> | |
struct is_filter : detail::has_trait<T, filter_tag> { }; | |
template<typename T> | |
struct is_direct : detail::has_trait<T, direct_tag> { }; | |
//------------------Definition of BOOST_IOSTREAMS_STREAMBUF_TYPEDEFS----------// | |
#define BOOST_IOSTREAMS_STREAMBUF_TYPEDEFS(Tr) \ | |
typedef Tr traits_type; \ | |
typedef typename traits_type::int_type int_type; \ | |
typedef typename traits_type::off_type off_type; \ | |
typedef typename traits_type::pos_type pos_type; \ | |
/**/ | |
} } // End namespaces iostreams, boost. | |
#include <boost/iostreams/detail/config/enable_warnings.hpp> | |
#endif // #ifndef BOOST_IOSTREAMS_IO_TRAITS_HPP_INCLUDED |