# enc_filebuf.h

    00001 // filebuf with __enc_traits state type -*- C++ -*-
    00002
    00003 // Copyright (C) 2002, 2003 Free Software Foundation, Inc.
    00004 //
    00005 // This file is part of the GNU ISO C++ Library.  This library is free
    00006 // software; you can redistribute it and/or modify it under the
    00007 // terms of the GNU General Public License as published by the
    00008 // Free Software Foundation; either version 2, or (at your option)
    00009 // any later version.
    00010
    00011 // This library is distributed in the hope that it will be useful,
    00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
    00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00014 // GNU General Public License for more details.
    00015
    00016 // You should have received a copy of the GNU General Public License along
    00017 // with this library; see the file COPYING.  If not, write to the Free
    00018 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
    00019 // USA.
    00020
    00021 // As a special exception, you may use this file as part of a free software
    00022 // library without restriction.  Specifically, if other files instantiate
    00023 // templates or use macros or inline functions from this file, or you compile
    00024 // this file and link it with other files to produce an executable, this
    00025 // file does not by itself cause the resulting executable to be covered by
    00026 // the GNU General Public License.  This exception does not however
    00027 // invalidate any other reasons why the executable file might be covered by
    00028 // the GNU General Public License.
    00029
    00030 #include <fstream>
    00031 #include <locale>
    00032
    00033 namespace __gnu_cxx
    00034 {
    00035   // Custom traits type with __enc_traits for the state type, and the
    00036   // associated fpos<__enc_traits> for the position type, all other
    00037   // bits equivalent to the required char_traits instantiations.
    00038   template<typename _CharT>
    00039     struct enc_char_traits: public std::char_traits<_CharT>
    00040     {
    00041       typedef std::__enc_traits         state_type;
    00042       typedef typename std::fpos<state_type>    pos_type;
    00043     };
    00044
    00045   template<typename _CharT>
    00046     class enc_filebuf
    00047     : public std::basic_filebuf<_CharT, enc_char_traits<_CharT> >
    00048     {
    00049     public:
    00050       typedef enc_char_traits<_CharT>       traits_type;
    00051       typedef typename traits_type::state_type  state_type;
    00052       typedef typename traits_type::pos_type    pos_type;
    00053
    00054       enc_filebuf(state_type& __state)
    00055       : std::basic_filebuf<_CharT, enc_char_traits<_CharT> >()
    00056       {
    00057     this->_M_state_beg = __state;
    00058     this->_M_state_beg._M_init();
    00059       }
    00060
    00061     private:
    00062       // concept requirements:
    00063       // Set state type to something useful.
    00064       // Something more than copyconstructible is needed here, so
    00065       // require default and copy constructible + assignment operator.
    00066       __glibcxx_class_requires(state_type, _SGIAssignableConcept)
    00067     };
    00068 } // namespace __gnu_cxx