utf8_codecvt.hpp
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//
// Copyright (c) 2015 Artyom Beilis (Tonkikh)
//
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt
#ifndef BOOST_LOCALE_UTF8_CODECVT_HPP
#define BOOST_LOCALE_UTF8_CODECVT_HPP
#include <boost/locale/generic_codecvt.hpp>
#include <boost/locale/utf.hpp>
#include <boost/cstdint.hpp>
#include <locale>
namespace boost { namespace locale {
/// \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
template<typename CharType>
class utf8_codecvt : public generic_codecvt<CharType, utf8_codecvt<CharType>> {
public:
struct state_type {};
utf8_codecvt(size_t refs = 0) : generic_codecvt<CharType, utf8_codecvt<CharType>>(refs) {}
static int max_encoding_length() { return 4; }
static state_type initial_state(generic_codecvt_base::initial_convertion_state /* unused */)
{
return state_type();
}
static utf::code_point to_unicode(state_type&, const char*& begin, const char* end)
{
const char* p = begin;
utf::code_point c = utf::utf_traits<char>::decode(p, end);
if(c != utf::illegal && c != utf::incomplete)
begin = p;
return c;
}
static utf::code_point from_unicode(state_type&, utf::code_point u, char* begin, const char* end)
{
if(!utf::is_valid_codepoint(u))
return utf::illegal;
int width;
if((width = utf::utf_traits<char>::width(u)) > end - begin)
return utf::incomplete;
utf::utf_traits<char>::encode(u, begin);
return width;
}
};
}} // namespace boost::locale
#endif