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: #ifndef BOOST_IOSTREAMS_DETAIL_CHAINBUF_HPP_INCLUDED
Chris@16: #define BOOST_IOSTREAMS_DETAIL_CHAINBUF_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>                    // BOOST_MSVC, template friends.
Chris@16: #include <boost/detail/workaround.hpp>
Chris@16: #include <boost/iostreams/chain.hpp>
Chris@16: #include <boost/iostreams/detail/access_control.hpp>
Chris@16: #include <boost/iostreams/detail/config/wide_streams.hpp>
Chris@16: #include <boost/iostreams/detail/streambuf.hpp>
Chris@16: #include <boost/iostreams/detail/streambuf/linked_streambuf.hpp>
Chris@16: #include <boost/iostreams/detail/translate_int_type.hpp>
Chris@16: #include <boost/iostreams/traits.hpp>
Chris@16: #include <boost/noncopyable.hpp>
Chris@16: 
Chris@16: namespace boost { namespace iostreams { namespace detail {
Chris@16: 
Chris@16: //--------------Definition of chainbuf----------------------------------------//
Chris@16: 
Chris@16: //
Chris@16: // Template name: chainbuf.
Chris@16: // Description: Stream buffer which operates by delegating to the first
Chris@16: //      linked_streambuf in a chain.
Chris@16: // Template parameters:
Chris@16: //      Chain - The chain type.
Chris@16: //
Chris@16: template<typename Chain, typename Mode, typename Access>
Chris@16: class chainbuf
Chris@16:     : public BOOST_IOSTREAMS_BASIC_STREAMBUF(
Chris@16:                  typename Chain::char_type,
Chris@16:                  typename Chain::traits_type
Chris@16:              ),
Chris@16:       public access_control<typename Chain::client_type, Access>,
Chris@16:       private noncopyable
Chris@16: {
Chris@16: private:
Chris@16:     typedef access_control<chain_client<Chain>, Access>      client_type;
Chris@16: public:
Chris@16:     typedef typename Chain::char_type                        char_type;
Chris@16:     BOOST_IOSTREAMS_STREAMBUF_TYPEDEFS(typename Chain::traits_type)
Chris@16: protected:
Chris@16:     typedef linked_streambuf<char_type, traits_type>         delegate_type;
Chris@16:     chainbuf() { client_type::set_chain(&chain_); }
Chris@16:     int_type underflow() 
Chris@16:         { sentry t(this); return translate(delegate().underflow()); }
Chris@16:     int_type pbackfail(int_type c)
Chris@16:         { sentry t(this); return translate(delegate().pbackfail(c)); }
Chris@16:     std::streamsize xsgetn(char_type* s, std::streamsize n)
Chris@16:         { sentry t(this); return delegate().xsgetn(s, n); }
Chris@16:     int_type overflow(int_type c)
Chris@16:         { sentry t(this); return translate(delegate().overflow(c)); }
Chris@16:     std::streamsize xsputn(const char_type* s, std::streamsize n)
Chris@16:         { sentry t(this); return delegate().xsputn(s, n); }
Chris@16:     int sync() { sentry t(this); return delegate().sync(); }
Chris@16:     pos_type seekoff( off_type off, BOOST_IOS::seekdir way,
Chris@16:                       BOOST_IOS::openmode which =
Chris@16:                           BOOST_IOS::in | BOOST_IOS::out )
Chris@16:         { sentry t(this); return delegate().seekoff(off, way, which); }
Chris@16:     pos_type seekpos( pos_type sp,
Chris@16:                       BOOST_IOS::openmode which =
Chris@16:                           BOOST_IOS::in | BOOST_IOS::out )
Chris@16:         { sentry t(this); return delegate().seekpos(sp, which); }
Chris@16: protected:
Chris@16:     typedef BOOST_IOSTREAMS_BASIC_STREAMBUF(
Chris@16:                  typename Chain::char_type,
Chris@16:                  typename Chain::traits_type
Chris@16:              )                                               base_type;
Chris@16: //#if !BOOST_WORKAROUND(__GNUC__, == 2)                                 
Chris@16: //    BOOST_IOSTREAMS_USING_PROTECTED_STREAMBUF_MEMBERS(base_type)
Chris@16: //#endif
Chris@16: private:
Chris@16: 
Chris@16:     // Translate from std int_type to chain's int_type.
Chris@16:     typedef BOOST_IOSTREAMS_CHAR_TRAITS(char_type)           std_traits;
Chris@16:     typedef typename Chain::traits_type                      chain_traits;
Chris@16:     static typename chain_traits::int_type 
Chris@16:     translate(typename std_traits::int_type c)
Chris@16:         { return translate_int_type<std_traits, chain_traits>(c); }
Chris@16: 
Chris@16:     delegate_type& delegate() 
Chris@16:         { return static_cast<delegate_type&>(chain_.front()); }
Chris@16:     void get_pointers()
Chris@16:         {
Chris@16:             this->setg(delegate().eback(), delegate().gptr(), delegate().egptr());
Chris@16:             this->setp(delegate().pbase(), delegate().epptr());
Chris@16:             this->pbump((int) (delegate().pptr() - delegate().pbase()));
Chris@16:         }
Chris@16:     void set_pointers()
Chris@16:         {
Chris@16:             delegate().setg(this->eback(), this->gptr(), this->egptr());
Chris@16:             delegate().setp(this->pbase(), this->epptr());
Chris@16:             delegate().pbump((int) (this->pptr() - this->pbase()));
Chris@16:         }
Chris@16:     struct sentry {
Chris@16:         sentry(chainbuf<Chain, Mode, Access>* buf) : buf_(buf)
Chris@16:             { buf_->set_pointers(); }
Chris@16:         ~sentry() { buf_->get_pointers(); }
Chris@16:         chainbuf<Chain, Mode, Access>* buf_;
Chris@16:     };
Chris@16:     friend struct sentry;
Chris@16:     Chain chain_;
Chris@16: };
Chris@16: 
Chris@16: } } } // End namespaces detail, iostreams, boost.
Chris@16: 
Chris@16: #endif // #ifndef BOOST_IOSTREAMS_DETAIL_CHAINBUF_HPP_INCLUDED