src/ResText/codecvt.h

   1
   2 /**     Several code conversions facets.
   3
   4         E.g. this is how to convert UCS-2 to UTF-8
   5
   6         @code
   7         wifstream ifs("input", ios_base::binary);
   8         wofstream ofs("output", ios_base::binary);
   9
  10         ifs.rdbuf()->pubimbue(locale(locale(), new ucs2_conversion()));
  11         ofs.rbbuf()->pubimbue(locale(locale(), new utf8_conversion()));
  12         ofs << ifs.rdbuf();
  13         @endcode
  14
  15         @author Vladimir Prus <ghost@cs.msu.su>
  16
  17         @file
  18 */
  19
  20 #include <locale>
  21
  22 /**     Conversion facet that allows to use Unicode files in UCS-2 encoding */
  23 class ucs2_conversion
  24 : public std::codecvt<wchar_t, char, std::mbstate_t>
  25 {
  26 protected:
  27
  28         result do_in(std::mbstate_t& state,
  29                                  const char* from, const char* from_end, const char*& from_next,
  30                                  wchar_t* to, wchar_t* to_limit, wchar_t*& to_next) const;
  31
  32         result do_out(std::mbstate_t& state,
  33                                   const wchar_t* from, const wchar_t* from_end, const wchar_t*& from_next,
  34                                   char* to, char* to_limit, char*& to_next) const;
  35
  36     bool do_always_noconv() const throw() { return false; }
  37     int  do_encoding() const throw() { return 2; }
  38 };
  39
  40
  41 /**     Conversion facet that allows to read Unicode files in UTF-8 encoding */
  42 class utf8_conversion
  43 : public std::codecvt<wchar_t, char, std::mbstate_t>
  44 {
  45 protected:
  46
  47         result do_in(std::mbstate_t& state,
  48                                  const char* from, const char* from_end, const char*& from_next,
  49                                  wchar_t* to, wchar_t* to_limit, wchar_t*& to_next) const;
  50
  51         result do_out(std::mbstate_t& state,
  52                                   const wchar_t* from, const wchar_t* from_end, const wchar_t*& from_next,
  53                                   char* to, char* to_limit, char*& to_next) const;
  54
  55     bool do_always_noconv() const throw() { return false; }
  56     int  do_encoding() const throw() { return 2; }
  57 };