00001 // __enc_traits layer for filebuf -*- C++ -*- 00002 00003 // Copyright (C) 2002 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 state type, all other bits 00036 // equivalent to the required char_traits instantiations. 00037 template<typename _CharT> 00038 struct enc_char_traits: public std::char_traits<_CharT> 00039 { 00040 typedef std::__enc_traits state_type; 00041 }; 00042 00043 template<typename _CharT> 00044 class enc_filebuf 00045 : public std::basic_filebuf<_CharT, enc_char_traits<_CharT> > 00046 { 00047 public: 00048 typedef typename enc_char_traits<_CharT>::state_type state_type; 00049 00050 enc_filebuf(state_type& __state) 00051 : std::basic_filebuf<_CharT, enc_char_traits<_CharT> >() 00052 { 00053 this->_M_state_beg = __state; 00054 this->_M_state_beg._M_init(); 00055 } 00056 00057 private: 00058 // concept requirements: 00059 // Set state type to something useful. 00060 // Something more than copyconstructible is needed here, so 00061 // require default and copy constructible + assignment operator. 00062 __glibcxx_class_requires(state_type, _SGIAssignableConcept) 00063 }; 00064 } // namespace __gnu_cxx