ceph/src/boost/libs/locale/include/boost/locale/utf8_codecvt.hpp

   1 //
   2 //  Copyright (c) 2015 Artyom Beilis (Tonkikh)
   3 //
   4 //  Distributed under the Boost Software License, Version 1.0. (See
   5 //  accompanying file LICENSE_1_0.txt or copy at
   6 //  http://www.boost.org/LICENSE_1_0.txt)
   7 //
   8 #ifndef BOOST_LOCALE_UTF8_CODECVT_HPP
   9 #define BOOST_LOCALE_UTF8_CODECVT_HPP
  10
  11 #include <boost/locale/utf.hpp>
  12 #include <boost/locale/generic_codecvt.hpp>
  13 #include <boost/cstdint.hpp>
  14 #include <locale>
  15
  16 namespace boost {
  17 namespace locale {
  18
  19 ///
  20 /// \brief Geneneric utf8 codecvt facet, it allows to convert UTF-8 strings to UTF-16 and UTF-32 using wchar_t, char32_t and char16_t
  21 ///
  22 template<typename CharType>
  23 class utf8_codecvt : public generic_codecvt<CharType,utf8_codecvt<CharType> >
  24 {
  25 public:
  26
  27     struct state_type {};
  28
  29     utf8_codecvt(size_t refs = 0) : generic_codecvt<CharType,utf8_codecvt<CharType> >(refs)
  30     {
  31     }
  32
  33     static int max_encoding_length()
  34     {
  35         return 4;
  36     }
  37
  38     static state_type initial_state(generic_codecvt_base::initial_convertion_state /* unused */)
  39     {
  40         return state_type();
  41     }
  42     static utf::code_point to_unicode(state_type &,char const *&begin,char const *end)
  43     {
  44         char const *p=begin;
  45
  46         utf::code_point c = utf::utf_traits<char>::decode(p,end);
  47         if(c!=utf::illegal && c!=utf::incomplete)
  48             begin = p;
  49         return c;
  50     }
  51
  52     static utf::code_point from_unicode(state_type &,utf::code_point u,char *begin,char const *end)
  53     {
  54         if(!utf::is_valid_codepoint(u))
  55             return utf::illegal;
  56         int width;
  57         if((width=utf::utf_traits<char>::width(u)) > end - begin)
  58             return utf::incomplete;
  59         utf::utf_traits<char>::encode(u,begin);
  60         return width;
  61     }
  62 };
  63
  64 } // locale
  65 } // namespace boost
  66
  67 #endif
  68 ///
  69 // vim: tabstop=4 expandtab shiftwidth=4 softtabstop=4