elc::char_set::convert_impl 命名空间参考

函数
constexpr size_t	decode_utf8 (char32_t *out, const char8_t *in, size_t in_size_max) noexcept
constexpr size_t	get_decode_utf8_size (const char8_t *in) noexcept
constexpr size_t	decode_utf16 (char32_t *out, const char16_t *in, size_t in_size_max) noexcept
constexpr size_t	get_decode_utf16_size (const char16_t *in) noexcept
constexpr size_t	encode_utf8 (char8_t *out, char32_t in) noexcept
constexpr size_t	get_encode_utf8_size (char32_t in) noexcept
constexpr size_t	encode_utf16 (char16_t *out, char32_t in) noexcept
constexpr size_t	get_encode_utf16_size (char32_t in) noexcept

函数说明

decode_utf16()

constexpr size_t elc::char_set::convert_impl::decode_utf16 ( char32_t *  out, const char16_t *  in, size_t  in_size_max  )

inlineconstexprnoexcept

在文件 all_defs.cpp 第 17069 行定义.

                                                                                                       {
        const char16_t code1 = *in++;
        if(code1 >= 0xD800 && code1 < 0xDC00){ /* surrogate pair */
            if(in_size_max < 2)
                return npos;
            const char16_t code2 = *in++;
            if(code2 >= 0xDC00 && code2 < 0xE000){
                *out = (code1 << 10) + code2 - 0x35FDC00;
                return 2;
            }
            return npos;
        }
        *out = code1;
        return 1;
    }

decode_utf8()

constexpr size_t elc::char_set::convert_impl::decode_utf8 ( char32_t *  out, const char8_t *  in, size_t  in_size_max  )

inlineconstexprnoexcept

在文件 all_defs.cpp 第 16999 行定义.

                                                                                                     {
        push_and_disable_msvc_warning(26494);//未初始化警告diss
        char8_t code1, code2, code3, code4;
        pop_msvc_warning();
        code1 = *in++;
        if(code1 < 0x80){ /* 1-byte sequence */
            *out = code1;
            return 1;
        }
        elseif(code1 < 0xC2)
            return npos;
        elseif(code1 < 0xE0){ /* 2-byte sequence */
            if(in_size_max < 2)
                return npos;
            code2 = *in++;
            if((code2 & 0xC0) != 0x80)
                return npos;
            *out = (code1 << 6) + code2 - 0x3080;
            return 2;
        }
        elseif(code1 < 0xF0){ /* 3-byte sequence */
            if(in_size_max < 3)
                return npos;
            code2 = *in++;
            if((code2 & 0xC0) != 0x80)
                return npos;
            if(code1 == 0xE0 && code2 < 0xA0)
                return npos;
            code3 = *in++;
            if((code3 & 0xC0) != 0x80)
                return npos;
            *out = (code1 << 12) + (code2 << 6) + code3 - 0xE2080;
            return 3;
        }
        elseif(code1 < 0xF5){ /* 4-byte sequence */
            if(in_size_max < 4)
                return npos;
            code2 = *in++;
            if((code2 & 0xC0) != 0x80)
                return npos;
            if(code1 == 0xF0 && code2 < 0x90)
                return npos;
            if(code1 == 0xF4 && code2 >= 0x90)
                return npos;
            code3 = *in++;
            if((code3 & 0xC0) != 0x80)
                return npos;
            code4 = *in++;
            if((code4 & 0xC0) != 0x80)
                return npos;
            *out = (code1 << 18) + (code2 << 12) + (code3 << 6) + code4 - 0x3C82080;
            return 4;
        }
        else
            return npos;
    }

encode_utf16()

constexpr size_t elc::char_set::convert_impl::encode_utf16 ( char16_t *  out, char32_t  in  )

inlineconstexprnoexcept

在文件 all_defs.cpp 第 17127 行定义.

                                                                            {
        if(in < 0x10000){
            *out++ = char16_t(in);
            return 1;
        }
        elseif(in < 0x110000){
            *out++ = char16_t((in >> 10) + 0xD7C0);
            *out++ = (in & 0x3FF) + 0xDC00;
            return 2;
        }
        return npos;
    }

encode_utf8()

constexpr size_t elc::char_set::convert_impl::encode_utf8 ( char8_t *  out, char32_t  in  )

inlineconstexprnoexcept

在文件 all_defs.cpp 第 17090 行定义.

                                                                          {
        if(in < 0x80){
            *out++ = (char8_t)in;
            return 1;
        }
        elseif(in < 0x800){
            *out++ = char8_t((in >> 6) + 0xC0);
            *out++ = char8_t((in & 0x3F) + 0x80);
            return 2;
        }
        elseif(in < 0x10000){
            *out++ = char8_t((in >> 12) + 0xE0);
            *out++ = ((in >> 6) & 0x3F) + 0x80;
            *out++ = (in & 0x3F) + 0x80;
            return 3;
        }
        elseif(in < 0x110000){
            *out++ = char8_t((in >> 18) + 0xF0);
            *out++ = ((in >> 12) & 0x3F) + 0x80;
            *out++ = ((in >> 6) & 0x3F) + 0x80;
            *out++ = (in & 0x3F) + 0x80;
            return 4;
        }
        return npos;
    }

get_decode_utf16_size()

constexpr size_t elc::char_set::convert_impl::get_decode_utf16_size ( const char16_t *  in )

inlineconstexprnoexcept

在文件 all_defs.cpp 第 17084 行定义.

                                                                             {
        if(*in >= 0xD800 && *in < 0xDC00) /* surrogate pair */
            return 2;
        else
            return 1;
    }

get_decode_utf8_size()

constexpr size_t elc::char_set::convert_impl::get_decode_utf8_size ( const char8_t *  in )

inlineconstexprnoexcept

在文件 all_defs.cpp 第 17055 行定义.

                                                                           {
        if(*in < 0x80) /* 1-byte sequence */
            return 1;
        elseif(*in < 0xC2)
            return npos;
        elseif(*in < 0xE0) /* 2-byte sequence */
            return 2;
        elseif(*in < 0xF0) /* 3-byte sequence */
            return 3;
        elseif(*in < 0xF5) /* 4-byte sequence */
            return 4;
        else
            return npos;
    }

get_encode_utf16_size()

constexpr size_t elc::char_set::convert_impl::get_encode_utf16_size ( char32_t  in )

inlineconstexprnoexcept

在文件 all_defs.cpp 第 17139 行定义.

                                                                      {
        if(in < 0x10000)
            return 1;
        elseif(in < 0x110000)
            return 2;
        else
            return npos;
    }

get_encode_utf8_size()

constexpr size_t elc::char_set::convert_impl::get_encode_utf8_size ( char32_t  in )

inlineconstexprnoexcept

在文件 all_defs.cpp 第 17115 行定义.

                                                                     {
        if(in < 0x80)
            return 1;
        elseif(in < 0x800)
            return 2;
        elseif(in < 0x10000)
            return 3;
        elseif(in < 0x110000)
            return 4;
        else
            return npos;
    }