libstdc++-v3/include/ext/enc_filebuf.h

   1 // filebuf with encoding state type -*- C++ -*-
   2
   3 // Copyright (C) 2002-2024 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // Under Section 7 of GPL version 3, you are granted additional
  17 // permissions described in the GCC Runtime Library Exception, version
  18 // 3.1, as published by the Free Software Foundation.
  19
  20 // You should have received a copy of the GNU General Public License and
  21 // a copy of the GCC Runtime Library Exception along with this program;
  22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 // <http://www.gnu.org/licenses/>.
  24
  25 /** @file ext/enc_filebuf.h
  26  *  This file is a GNU extension to the Standard C++ Library.
  27  */
  28
  29 #ifndef _EXT_ENC_FILEBUF_H
  30 #define _EXT_ENC_FILEBUF_H 1
  31
  32 #include <bits/requires_hosted.h> // GNU extensions are currently omitted
  33
  34 #include <fstream>
  35 #include <locale>
  36 #include <ext/codecvt_specializations.h>
  37
  38 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
  39 {
  40 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  41
  42   /// class enc_filebuf.
  43   template<typename _CharT>
  44     class enc_filebuf
  45     : public std::basic_filebuf<_CharT, encoding_char_traits<_CharT> >
  46     {
  47     public:
  48       typedef encoding_char_traits<_CharT>      traits_type;
  49       typedef typename traits_type::state_type  state_type;
  50       typedef typename traits_type::pos_type    pos_type;
  51
  52       enc_filebuf(state_type& __state)
  53       : std::basic_filebuf<_CharT, encoding_char_traits<_CharT> >()
  54       { this->_M_state_beg = __state; }
  55
  56     private:
  57       // concept requirements:
  58       // Set state type to something useful.
  59       // Something more than copyconstructible is needed here, so
  60       // require default and copy constructible + assignment operator.
  61       __glibcxx_class_requires(state_type, _SGIAssignableConcept)
  62     };
  63
  64 _GLIBCXX_END_NAMESPACE_VERSION
  65 } // namespace
  66
  67 #endif