57 lines
1.8 KiB
C++
57 lines
1.8 KiB
C++
//
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// Copyright (c) 2015 Artyom Beilis (Tonkikh)
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//
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// Distributed under the Boost Software License, Version 1.0.
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// https://www.boost.org/LICENSE_1_0.txt
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#ifndef BOOST_LOCALE_UTF8_CODECVT_HPP
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#define BOOST_LOCALE_UTF8_CODECVT_HPP
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#include <boost/locale/generic_codecvt.hpp>
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#include <boost/locale/utf.hpp>
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#include <boost/assert.hpp>
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#include <cstdint>
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#include <locale>
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namespace boost { namespace locale {
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/// \brief Generic utf8 codecvt facet, it allows to convert UTF-8 strings to UTF-16 and UTF-32 using wchar_t,
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/// char32_t and char16_t
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template<typename CharType>
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class utf8_codecvt : public generic_codecvt<CharType, utf8_codecvt<CharType>> {
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public:
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struct state_type {};
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utf8_codecvt(size_t refs = 0) : generic_codecvt<CharType, utf8_codecvt<CharType>>(refs) {}
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static int max_encoding_length() { return 4; }
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static state_type initial_state(generic_codecvt_base::initial_convertion_state /* unused */)
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{
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return state_type();
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}
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static utf::code_point to_unicode(state_type&, const char*& begin, const char* end)
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{
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const char* p = begin;
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utf::code_point c = utf::utf_traits<char>::decode(p, end);
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if(c != utf::illegal && c != utf::incomplete)
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begin = p;
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return c;
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}
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static utf::len_or_error from_unicode(state_type&, utf::code_point u, char* begin, const char* end)
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{
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BOOST_ASSERT(utf::is_valid_codepoint(u));
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const auto width = utf::utf_traits<char>::width(u);
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if(width > end - begin)
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return utf::incomplete;
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utf::utf_traits<char>::encode(u, begin);
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return width;
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}
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};
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}} // namespace boost::locale
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#endif
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