Chris@16: // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
Chris@16: // (C) Copyright 2003-2007 Jonathan Turkanis
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16: // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
Chris@16: 
Chris@16: // See http://www.boost.org/libs/iostreams for documentation.
Chris@16: 
Chris@16: // To do: add support for random-access.
Chris@16: 
Chris@16: #ifndef BOOST_IOSTREAMS_COMBINE_HPP_INCLUDED
Chris@16: #define BOOST_IOSTREAMS_COMBINE_HPP_INCLUDED
Chris@16: 
Chris@16: #if defined(_MSC_VER) && (_MSC_VER >= 1020)
Chris@16: # pragma once
Chris@16: #endif              
Chris@16: 
Chris@16: #include <boost/config.hpp> // NO_STD_LOCALE, DEDUCED_TYPENAME.
Chris@16: #ifndef BOOST_NO_STD_LOCALE
Chris@16: # include <locale>
Chris@16: #endif
Chris@16: #include <boost/iostreams/detail/ios.hpp>   
Chris@16: #include <boost/iostreams/detail/wrap_unwrap.hpp>       
Chris@16: #include <boost/iostreams/traits.hpp>         
Chris@16: #include <boost/iostreams/operations.hpp>        
Chris@16: #include <boost/mpl/if.hpp>    
Chris@16: #include <boost/static_assert.hpp>  
Chris@16: #include <boost/type_traits/is_convertible.hpp>
Chris@16: #include <boost/type_traits/is_same.hpp> 
Chris@16: 
Chris@16: // Must come last.
Chris@16: #include <boost/iostreams/detail/config/disable_warnings.hpp>
Chris@16: 
Chris@16: namespace boost { namespace iostreams {
Chris@16: 
Chris@16: namespace detail {
Chris@16: 
Chris@16: //
Chris@16: // Template name: combined_device.
Chris@16: // Description: Model of Device defined in terms of a Source/Sink pair.
Chris@16: // Template parameters:
Chris@16: //      Source - A model of Source, with the same char_type and traits_type
Chris@16: //          as Sink.
Chris@16: //      Sink - A model of Sink, with the same char_type and traits_type
Chris@16: //          as Source.
Chris@16: //
Chris@16: template<typename Source, typename Sink>
Chris@16: class combined_device {
Chris@16: private:
Chris@16:     typedef typename category_of<Source>::type  in_category;
Chris@16:     typedef typename category_of<Sink>::type    out_category;
Chris@16:     typedef typename char_type_of<Sink>::type   sink_char_type;
Chris@16: public:
Chris@16:     typedef typename char_type_of<Source>::type char_type;
Chris@16:     struct category
Chris@16:         : bidirectional, 
Chris@16:           device_tag, 
Chris@16:           closable_tag, 
Chris@16:           localizable_tag
Chris@16:         { };
Chris@16:     BOOST_STATIC_ASSERT(is_device<Source>::value);
Chris@16:     BOOST_STATIC_ASSERT(is_device<Sink>::value);
Chris@16:     BOOST_STATIC_ASSERT((is_convertible<in_category, input>::value));
Chris@16:     BOOST_STATIC_ASSERT((is_convertible<out_category, output>::value));
Chris@16:     BOOST_STATIC_ASSERT((is_same<char_type, sink_char_type>::value));
Chris@16:     combined_device(const Source& src, const Sink& snk);
Chris@16:     std::streamsize read(char_type* s, std::streamsize n);
Chris@16:     std::streamsize write(const char_type* s, std::streamsize n);
Chris@16:     void close(BOOST_IOS::openmode);
Chris@16:     #ifndef BOOST_NO_STD_LOCALE
Chris@16:         void imbue(const std::locale& loc);
Chris@16:     #endif
Chris@16: private:
Chris@16:     Source  src_;
Chris@16:     Sink    sink_;
Chris@16: };
Chris@16: 
Chris@16: //
Chris@16: // Template name: combined_filter.
Chris@16: // Description: Model of Device defined in terms of a Source/Sink pair.
Chris@16: // Template parameters:
Chris@16: //      InputFilter - A model of InputFilter, with the same char_type as 
Chris@16: //          OutputFilter.
Chris@16: //      OutputFilter - A model of OutputFilter, with the same char_type as 
Chris@16: //          InputFilter.
Chris@16: //
Chris@16: template<typename InputFilter, typename OutputFilter>
Chris@16: class combined_filter {
Chris@16: private:
Chris@16:     typedef typename category_of<InputFilter>::type    in_category;
Chris@16:     typedef typename category_of<OutputFilter>::type   out_category;
Chris@16:     typedef typename char_type_of<OutputFilter>::type  output_char_type;
Chris@16: public:
Chris@16:     typedef typename char_type_of<InputFilter>::type   char_type;
Chris@16:     struct category 
Chris@16:         : multichar_bidirectional_filter_tag,
Chris@16:           closable_tag, 
Chris@16:           localizable_tag
Chris@16:         { };
Chris@16:     BOOST_STATIC_ASSERT(is_filter<InputFilter>::value);
Chris@16:     BOOST_STATIC_ASSERT(is_filter<OutputFilter>::value);
Chris@16:     BOOST_STATIC_ASSERT((is_convertible<in_category, input>::value));
Chris@16:     BOOST_STATIC_ASSERT((is_convertible<out_category, output>::value));
Chris@16:     BOOST_STATIC_ASSERT((is_same<char_type, output_char_type>::value));
Chris@16:     combined_filter(const InputFilter& in, const OutputFilter& out);
Chris@16: 
Chris@16:     template<typename Source>
Chris@16:     std::streamsize read(Source& src, char_type* s, std::streamsize n)
Chris@16:     { return boost::iostreams::read(in_, src, s, n); }
Chris@16: 
Chris@16:     template<typename Sink>
Chris@16:     std::streamsize write(Sink& snk, const char_type* s, std::streamsize n)
Chris@16:     { return boost::iostreams::write(out_, snk, s, n); }
Chris@16: 
Chris@16:     template<typename Sink>
Chris@16:     void close(Sink& snk, BOOST_IOS::openmode which)
Chris@16:     {
Chris@16:         if (which == BOOST_IOS::in) {
Chris@16:             if (is_convertible<in_category, dual_use>::value) {
Chris@16:                 iostreams::close(in_, snk, BOOST_IOS::in);
Chris@16:             } else {
Chris@16:                 detail::close_all(in_, snk);
Chris@16:             }
Chris@16:         }
Chris@16:         if (which == BOOST_IOS::out) {
Chris@16:             if (is_convertible<out_category, dual_use>::value) {
Chris@16:                 iostreams::close(out_, snk, BOOST_IOS::out);
Chris@16:             } else {
Chris@16:                 detail::close_all(out_, snk);
Chris@16:             }
Chris@16:         }
Chris@16:     }
Chris@16:     #ifndef BOOST_NO_STD_LOCALE
Chris@16:         void imbue(const std::locale& loc);
Chris@16:     #endif
Chris@16: private:
Chris@16:     InputFilter   in_;
Chris@16:     OutputFilter  out_;
Chris@16: };
Chris@16: 
Chris@16: template<typename In, typename Out>
Chris@16: struct combination_traits 
Chris@16:     : mpl::if_<
Chris@16:           is_device<In>,
Chris@16:           combined_device<
Chris@16:               typename wrapped_type<In>::type,
Chris@16:               typename wrapped_type<Out>::type
Chris@16:           >,
Chris@16:           combined_filter<
Chris@16:               typename wrapped_type<In>::type,
Chris@16:               typename wrapped_type<Out>::type
Chris@16:           >
Chris@16:       >
Chris@16:     { };
Chris@16: 
Chris@16: } // End namespace detail.
Chris@16: 
Chris@16: template<typename In, typename Out>
Chris@16: struct combination : detail::combination_traits<In, Out>::type {
Chris@16:     typedef typename detail::combination_traits<In, Out>::type  base_type;
Chris@16:     typedef typename detail::wrapped_type<In>::type          in_type;
Chris@16:     typedef typename detail::wrapped_type<Out>::type         out_type;
Chris@16:     combination(const in_type& in, const out_type& out)
Chris@16:         : base_type(in, out) { }
Chris@16: };
Chris@16: 
Chris@16: namespace detail {
Chris@16: 
Chris@16: // Workaround for VC6 ETI bug.
Chris@16: template<typename In, typename Out>
Chris@16: struct combine_traits {
Chris@16:     typedef combination<
Chris@16:                 BOOST_DEDUCED_TYPENAME detail::unwrapped_type<In>::type, 
Chris@16:                 BOOST_DEDUCED_TYPENAME detail::unwrapped_type<Out>::type
Chris@16:             > type;
Chris@16: };
Chris@16: 
Chris@16: } // End namespace detail.
Chris@16: 
Chris@16: //
Chris@16: // Template name: combine.
Chris@16: // Description: Takes a Source/Sink pair or InputFilter/OutputFilter pair and
Chris@16: //      returns a Source or Filter which performs input using the first member
Chris@16: //      of the pair and output using the second member of the pair.
Chris@16: // Template parameters:
Chris@16: //      In - A model of Source or InputFilter, with the same char_type as Out.
Chris@16: //      Out - A model of Sink or OutputFilter, with the same char_type as In.
Chris@16: //
Chris@16: template<typename In, typename Out>
Chris@16: typename detail::combine_traits<In, Out>::type
Chris@16: combine(const In& in, const Out& out) 
Chris@16: { 
Chris@16:     typedef typename detail::combine_traits<In, Out>::type return_type;
Chris@16:     return return_type(in, out); 
Chris@16: }
Chris@16: 
Chris@16: //----------------------------------------------------------------------------//
Chris@16: 
Chris@16: namespace detail {
Chris@16: 
Chris@16: //--------------Implementation of combined_device-----------------------------//
Chris@16: 
Chris@16: template<typename Source, typename Sink>
Chris@16: inline combined_device<Source, Sink>::combined_device
Chris@16:     (const Source& src, const Sink& snk)
Chris@16:     : src_(src), sink_(snk) { }
Chris@16: 
Chris@16: template<typename Source, typename Sink>
Chris@16: inline std::streamsize
Chris@16: combined_device<Source, Sink>::read(char_type* s, std::streamsize n)
Chris@16: { return iostreams::read(src_, s, n); }
Chris@16: 
Chris@16: template<typename Source, typename Sink>
Chris@16: inline std::streamsize
Chris@16: combined_device<Source, Sink>::write(const char_type* s, std::streamsize n)
Chris@16: { return iostreams::write(sink_, s, n); }
Chris@16: 
Chris@16: template<typename Source, typename Sink>
Chris@16: inline void
Chris@16: combined_device<Source, Sink>::close(BOOST_IOS::openmode which)
Chris@16: { 
Chris@16:     if (which == BOOST_IOS::in)
Chris@16:         detail::close_all(src_); 
Chris@16:     if (which == BOOST_IOS::out)
Chris@16:         detail::close_all(sink_); 
Chris@16: }
Chris@16: 
Chris@16: #ifndef BOOST_NO_STD_LOCALE
Chris@16:     template<typename Source, typename Sink>
Chris@16:     void combined_device<Source, Sink>::imbue(const std::locale& loc)
Chris@16:     {
Chris@16:         iostreams::imbue(src_, loc);
Chris@16:         iostreams::imbue(sink_, loc);
Chris@16:     }
Chris@16: #endif
Chris@16: 
Chris@16: //--------------Implementation of filter_pair---------------------------------//
Chris@16: 
Chris@16: template<typename InputFilter, typename OutputFilter>
Chris@16: inline combined_filter<InputFilter, OutputFilter>::combined_filter
Chris@16:     (const InputFilter& in, const OutputFilter& out) : in_(in), out_(out)
Chris@16:     { }
Chris@16: 
Chris@16: #ifndef BOOST_NO_STD_LOCALE
Chris@16:     template<typename InputFilter, typename OutputFilter>
Chris@16:     void combined_filter<InputFilter, OutputFilter>::imbue
Chris@16:         (const std::locale& loc)
Chris@16:     {
Chris@16:         iostreams::imbue(in_, loc);
Chris@16:         iostreams::imbue(out_, loc);
Chris@16:     }
Chris@16: #endif
Chris@16: 
Chris@16: 
Chris@16: } // End namespace detail.
Chris@16: 
Chris@16: } } // End namespaces iostreams, boost.
Chris@16: 
Chris@16: #include <boost/iostreams/detail/config/enable_warnings.hpp>
Chris@16: 
Chris@16: #endif // #ifndef BOOST_IOSTREAMS_COMBINE_HPP_INCLUDED