bool parse_cbor_internal()

in MiniEngine/Model/json.hpp [8371:8804]


    bool parse_cbor_internal(const bool get_char,
                             const cbor_tag_handler_t tag_handler)
    {
        switch (get_char ? get() : current)
        {
            // EOF
            case std::char_traits<char_type>::eof():
                return unexpect_eof(input_format_t::cbor, "value");

            // Integer 0x00..0x17 (0..23)
            case 0x00:
            case 0x01:
            case 0x02:
            case 0x03:
            case 0x04:
            case 0x05:
            case 0x06:
            case 0x07:
            case 0x08:
            case 0x09:
            case 0x0A:
            case 0x0B:
            case 0x0C:
            case 0x0D:
            case 0x0E:
            case 0x0F:
            case 0x10:
            case 0x11:
            case 0x12:
            case 0x13:
            case 0x14:
            case 0x15:
            case 0x16:
            case 0x17:
                return sax->number_unsigned(static_cast<number_unsigned_t>(current));

            case 0x18: // Unsigned integer (one-byte uint8_t follows)
            {
                std::uint8_t number{};
                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
            }

            case 0x19: // Unsigned integer (two-byte uint16_t follows)
            {
                std::uint16_t number{};
                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
            }

            case 0x1A: // Unsigned integer (four-byte uint32_t follows)
            {
                std::uint32_t number{};
                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
            }

            case 0x1B: // Unsigned integer (eight-byte uint64_t follows)
            {
                std::uint64_t number{};
                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
            }

            // Negative integer -1-0x00..-1-0x17 (-1..-24)
            case 0x20:
            case 0x21:
            case 0x22:
            case 0x23:
            case 0x24:
            case 0x25:
            case 0x26:
            case 0x27:
            case 0x28:
            case 0x29:
            case 0x2A:
            case 0x2B:
            case 0x2C:
            case 0x2D:
            case 0x2E:
            case 0x2F:
            case 0x30:
            case 0x31:
            case 0x32:
            case 0x33:
            case 0x34:
            case 0x35:
            case 0x36:
            case 0x37:
                return sax->number_integer(static_cast<std::int8_t>(0x20 - 1 - current));

            case 0x38: // Negative integer (one-byte uint8_t follows)
            {
                std::uint8_t number{};
                return get_number(input_format_t::cbor, number) && sax->number_integer(static_cast<number_integer_t>(-1) - number);
            }

            case 0x39: // Negative integer -1-n (two-byte uint16_t follows)
            {
                std::uint16_t number{};
                return get_number(input_format_t::cbor, number) && sax->number_integer(static_cast<number_integer_t>(-1) - number);
            }

            case 0x3A: // Negative integer -1-n (four-byte uint32_t follows)
            {
                std::uint32_t number{};
                return get_number(input_format_t::cbor, number) && sax->number_integer(static_cast<number_integer_t>(-1) - number);
            }

            case 0x3B: // Negative integer -1-n (eight-byte uint64_t follows)
            {
                std::uint64_t number{};
                return get_number(input_format_t::cbor, number) && sax->number_integer(static_cast<number_integer_t>(-1)
                        - static_cast<number_integer_t>(number));
            }

            // Binary data (0x00..0x17 bytes follow)
            case 0x40:
            case 0x41:
            case 0x42:
            case 0x43:
            case 0x44:
            case 0x45:
            case 0x46:
            case 0x47:
            case 0x48:
            case 0x49:
            case 0x4A:
            case 0x4B:
            case 0x4C:
            case 0x4D:
            case 0x4E:
            case 0x4F:
            case 0x50:
            case 0x51:
            case 0x52:
            case 0x53:
            case 0x54:
            case 0x55:
            case 0x56:
            case 0x57:
            case 0x58: // Binary data (one-byte uint8_t for n follows)
            case 0x59: // Binary data (two-byte uint16_t for n follow)
            case 0x5A: // Binary data (four-byte uint32_t for n follow)
            case 0x5B: // Binary data (eight-byte uint64_t for n follow)
            case 0x5F: // Binary data (indefinite length)
            {
                binary_t b;
                return get_cbor_binary(b) && sax->binary(b);
            }

            // UTF-8 string (0x00..0x17 bytes follow)
            case 0x60:
            case 0x61:
            case 0x62:
            case 0x63:
            case 0x64:
            case 0x65:
            case 0x66:
            case 0x67:
            case 0x68:
            case 0x69:
            case 0x6A:
            case 0x6B:
            case 0x6C:
            case 0x6D:
            case 0x6E:
            case 0x6F:
            case 0x70:
            case 0x71:
            case 0x72:
            case 0x73:
            case 0x74:
            case 0x75:
            case 0x76:
            case 0x77:
            case 0x78: // UTF-8 string (one-byte uint8_t for n follows)
            case 0x79: // UTF-8 string (two-byte uint16_t for n follow)
            case 0x7A: // UTF-8 string (four-byte uint32_t for n follow)
            case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow)
            case 0x7F: // UTF-8 string (indefinite length)
            {
                string_t s;
                return get_cbor_string(s) && sax->string(s);
            }

            // array (0x00..0x17 data items follow)
            case 0x80:
            case 0x81:
            case 0x82:
            case 0x83:
            case 0x84:
            case 0x85:
            case 0x86:
            case 0x87:
            case 0x88:
            case 0x89:
            case 0x8A:
            case 0x8B:
            case 0x8C:
            case 0x8D:
            case 0x8E:
            case 0x8F:
            case 0x90:
            case 0x91:
            case 0x92:
            case 0x93:
            case 0x94:
            case 0x95:
            case 0x96:
            case 0x97:
                return get_cbor_array(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x1Fu), tag_handler);

            case 0x98: // array (one-byte uint8_t for n follows)
            {
                std::uint8_t len{};
                return get_number(input_format_t::cbor, len) && get_cbor_array(static_cast<std::size_t>(len), tag_handler);
            }

            case 0x99: // array (two-byte uint16_t for n follow)
            {
                std::uint16_t len{};
                return get_number(input_format_t::cbor, len) && get_cbor_array(static_cast<std::size_t>(len), tag_handler);
            }

            case 0x9A: // array (four-byte uint32_t for n follow)
            {
                std::uint32_t len{};
                return get_number(input_format_t::cbor, len) && get_cbor_array(static_cast<std::size_t>(len), tag_handler);
            }

            case 0x9B: // array (eight-byte uint64_t for n follow)
            {
                std::uint64_t len{};
                return get_number(input_format_t::cbor, len) && get_cbor_array(static_cast<std::size_t>(len), tag_handler);
            }

            case 0x9F: // array (indefinite length)
                return get_cbor_array(std::size_t(-1), tag_handler);

            // map (0x00..0x17 pairs of data items follow)
            case 0xA0:
            case 0xA1:
            case 0xA2:
            case 0xA3:
            case 0xA4:
            case 0xA5:
            case 0xA6:
            case 0xA7:
            case 0xA8:
            case 0xA9:
            case 0xAA:
            case 0xAB:
            case 0xAC:
            case 0xAD:
            case 0xAE:
            case 0xAF:
            case 0xB0:
            case 0xB1:
            case 0xB2:
            case 0xB3:
            case 0xB4:
            case 0xB5:
            case 0xB6:
            case 0xB7:
                return get_cbor_object(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x1Fu), tag_handler);

            case 0xB8: // map (one-byte uint8_t for n follows)
            {
                std::uint8_t len{};
                return get_number(input_format_t::cbor, len) && get_cbor_object(static_cast<std::size_t>(len), tag_handler);
            }

            case 0xB9: // map (two-byte uint16_t for n follow)
            {
                std::uint16_t len{};
                return get_number(input_format_t::cbor, len) && get_cbor_object(static_cast<std::size_t>(len), tag_handler);
            }

            case 0xBA: // map (four-byte uint32_t for n follow)
            {
                std::uint32_t len{};
                return get_number(input_format_t::cbor, len) && get_cbor_object(static_cast<std::size_t>(len), tag_handler);
            }

            case 0xBB: // map (eight-byte uint64_t for n follow)
            {
                std::uint64_t len{};
                return get_number(input_format_t::cbor, len) && get_cbor_object(static_cast<std::size_t>(len), tag_handler);
            }

            case 0xBF: // map (indefinite length)
                return get_cbor_object(std::size_t(-1), tag_handler);

            case 0xC6: // tagged item
            case 0xC7:
            case 0xC8:
            case 0xC9:
            case 0xCA:
            case 0xCB:
            case 0xCC:
            case 0xCD:
            case 0xCE:
            case 0xCF:
            case 0xD0:
            case 0xD1:
            case 0xD2:
            case 0xD3:
            case 0xD4:
            case 0xD8: // tagged item (1 bytes follow)
            case 0xD9: // tagged item (2 bytes follow)
            case 0xDA: // tagged item (4 bytes follow)
            case 0xDB: // tagged item (8 bytes follow)
            {
                switch (tag_handler)
                {
                    case cbor_tag_handler_t::error:
                    {
                        auto last_token = get_token_string();
                        return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::cbor, "invalid byte: 0x" + last_token, "value"), BasicJsonType()));
                    }

                    case cbor_tag_handler_t::ignore:
                    {
                        switch (current)
                        {
                            case 0xD8:
                            {
                                std::uint8_t len{};
                                get_number(input_format_t::cbor, len);
                                break;
                            }
                            case 0xD9:
                            {
                                std::uint16_t len{};
                                get_number(input_format_t::cbor, len);
                                break;
                            }
                            case 0xDA:
                            {
                                std::uint32_t len{};
                                get_number(input_format_t::cbor, len);
                                break;
                            }
                            case 0xDB:
                            {
                                std::uint64_t len{};
                                get_number(input_format_t::cbor, len);
                                break;
                            }
                            default:
                                break;
                        }
                        return parse_cbor_internal(true, tag_handler);
                    }

                    default:                 // LCOV_EXCL_LINE
                        JSON_ASSERT(false);  // LCOV_EXCL_LINE
                        return false;        // LCOV_EXCL_LINE
                }
            }

            case 0xF4: // false
                return sax->boolean(false);

            case 0xF5: // true
                return sax->boolean(true);

            case 0xF6: // null
                return sax->null();

            case 0xF9: // Half-Precision Float (two-byte IEEE 754)
            {
                const auto byte1_raw = get();
                if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::cbor, "number")))
                {
                    return false;
                }
                const auto byte2_raw = get();
                if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::cbor, "number")))
                {
                    return false;
                }

                const auto byte1 = static_cast<unsigned char>(byte1_raw);
                const auto byte2 = static_cast<unsigned char>(byte2_raw);

                // code from RFC 7049, Appendix D, Figure 3:
                // As half-precision floating-point numbers were only added
                // to IEEE 754 in 2008, today's programming platforms often
                // still only have limited support for them. It is very
                // easy to include at least decoding support for them even
                // without such support. An example of a small decoder for
                // half-precision floating-point numbers in the C language
                // is shown in Fig. 3.
                const auto half = static_cast<unsigned int>((byte1 << 8u) + byte2);
                const double val = [&half]
                {
                    const int exp = (half >> 10u) & 0x1Fu;
                    const unsigned int mant = half & 0x3FFu;
                    JSON_ASSERT(0 <= exp&& exp <= 32);
                    JSON_ASSERT(mant <= 1024);
                    switch (exp)
                    {
                        case 0:
                            return std::ldexp(mant, -24);
                        case 31:
                            return (mant == 0)
                            ? std::numeric_limits<double>::infinity()
                            : std::numeric_limits<double>::quiet_NaN();
                        default:
                            return std::ldexp(mant + 1024, exp - 25);
                    }
                }();
                return sax->number_float((half & 0x8000u) != 0
                                         ? static_cast<number_float_t>(-val)
                                         : static_cast<number_float_t>(val), "");
            }

            case 0xFA: // Single-Precision Float (four-byte IEEE 754)
            {
                float number{};
                return get_number(input_format_t::cbor, number) && sax->number_float(static_cast<number_float_t>(number), "");
            }

            case 0xFB: // Double-Precision Float (eight-byte IEEE 754)
            {
                double number{};
                return get_number(input_format_t::cbor, number) && sax->number_float(static_cast<number_float_t>(number), "");
            }

            default: // anything else (0xFF is handled inside the other types)
            {
                auto last_token = get_token_string();
                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::cbor, "invalid byte: 0x" + last_token, "value"), BasicJsonType()));
            }
        }
    }