write_cbor()

template<typename BasicJsonType , typename CharType >

void nlohmann::detail::binary_writer< BasicJsonType, CharType >::write_cbor ( const BasicJsonType &  j )

inline

Parameters

[in]

j

JSON value to serialize

Definition at line 13846 of file json.hpp.

    {
        switch (j.type())
        {
            case value_t::null:
            {
                oa->write_character(to_char_type(0xF6));
                break;
            }
 
            case value_t::boolean:
            {
                oa->write_character(j.m_value.boolean
                                    ? to_char_type(0xF5)
                                    : to_char_type(0xF4));
                break;
            }
 
            case value_t::number_integer:
            {
                if (j.m_value.number_integer >= 0)
                {
                    // CBOR does not differentiate between positive signed
                    // integers and unsigned integers. Therefore, we used the
                    // code from the value_t::number_unsigned case here.
                    if (j.m_value.number_integer <= 0x17)
                    {
                        write_number(static_cast<std::uint8_t>(j.m_value.number_integer));
                    }
 
                    else if (j.m_value.number_integer <= (std::numeric_limits<std::uint8_t>::max)())
                    {
                        oa->write_character(to_char_type(0x18));
                        write_number(static_cast<std::uint8_t>(j.m_value.number_integer));
                    }
 
                    else if (j.m_value.number_integer <= (std::numeric_limits<std::uint16_t>::max)())
                    {
                        oa->write_character(to_char_type(0x19));
                        write_number(static_cast<std::uint16_t>(j.m_value.number_integer));
                    }
 
                    else if (j.m_value.number_integer <= (std::numeric_limits<std::uint32_t>::max)())
                    {
                        oa->write_character(to_char_type(0x1A));
                        write_number(static_cast<std::uint32_t>(j.m_value.number_integer));
                    }
 
                    else
                    {
                        oa->write_character(to_char_type(0x1B));
                        write_number(static_cast<std::uint64_t>(j.m_value.number_integer));
                    }
                }
 
                else
                {
                    // The conversions below encode the sign in the first
                    // byte, and the value is converted to a positive number.
                    const auto positive_number = -1 - j.m_value.number_integer;
 
                    if (j.m_value.number_integer >= -24)
                    {
                        write_number(static_cast<std::uint8_t>(0x20 + positive_number));
                    }
 
                    else if (positive_number <= (std::numeric_limits<std::uint8_t>::max)())
                    {
                        oa->write_character(to_char_type(0x38));
                        write_number(static_cast<std::uint8_t>(positive_number));
                    }
 
                    else if (positive_number <= (std::numeric_limits<std::uint16_t>::max)())
                    {
                        oa->write_character(to_char_type(0x39));
                        write_number(static_cast<std::uint16_t>(positive_number));
                    }
 
                    else if (positive_number <= (std::numeric_limits<std::uint32_t>::max)())
                    {
                        oa->write_character(to_char_type(0x3A));
                        write_number(static_cast<std::uint32_t>(positive_number));
                    }
 
                    else
                    {
                        oa->write_character(to_char_type(0x3B));
                        write_number(static_cast<std::uint64_t>(positive_number));
                    }
                }
 
                break;
            }
 
            case value_t::number_unsigned:
            {
                if (j.m_value.number_unsigned <= 0x17)
                {
                    write_number(static_cast<std::uint8_t>(j.m_value.number_unsigned));
                }
 
                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint8_t>::max)())
                {
                    oa->write_character(to_char_type(0x18));
                    write_number(static_cast<std::uint8_t>(j.m_value.number_unsigned));
                }
 
                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint16_t>::max)())
                {
                    oa->write_character(to_char_type(0x19));
                    write_number(static_cast<std::uint16_t>(j.m_value.number_unsigned));
                }
 
                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint32_t>::max)())
                {
                    oa->write_character(to_char_type(0x1A));
                    write_number(static_cast<std::uint32_t>(j.m_value.number_unsigned));
                }
 
                else
                {
                    oa->write_character(to_char_type(0x1B));
                    write_number(static_cast<std::uint64_t>(j.m_value.number_unsigned));
                }
 
                break;
            }
 
            case value_t::number_float:
            {
                if (std::isnan(j.m_value.number_float))
                {
                    // NaN is 0xf97e00 in CBOR
                    oa->write_character(to_char_type(0xF9));
                    oa->write_character(to_char_type(0x7E));
                    oa->write_character(to_char_type(0x00));
                }
 
                else if (std::isinf(j.m_value.number_float))
                {
                    // Infinity is 0xf97c00, -Infinity is 0xf9fc00
                    oa->write_character(to_char_type(0xf9));
                    oa->write_character(j.m_value.number_float > 0 ? to_char_type(0x7C) : to_char_type(0xFC));
                    oa->write_character(to_char_type(0x00));
                }
 
                else
                {
                    write_compact_float(j.m_value.number_float, detail::input_format_t::cbor);
                }
 
                break;
            }
 
            case value_t::string:
            {
                // step 1: write control byte and the string length
                const auto N = j.m_value.string->size();
 
                if (N <= 0x17)
                {
                    write_number(static_cast<std::uint8_t>(0x60 + N));
                }
 
                else if (N <= (std::numeric_limits<std::uint8_t>::max)())
                {
                    oa->write_character(to_char_type(0x78));
                    write_number(static_cast<std::uint8_t>(N));
                }
 
                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
                {
                    oa->write_character(to_char_type(0x79));
                    write_number(static_cast<std::uint16_t>(N));
                }
 
                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
                {
                    oa->write_character(to_char_type(0x7A));
                    write_number(static_cast<std::uint32_t>(N));
                }
 
                // LCOV_EXCL_START
                else if (N <= (std::numeric_limits<std::uint64_t>::max)())
                {
                    oa->write_character(to_char_type(0x7B));
                    write_number(static_cast<std::uint64_t>(N));
                }
 
                // LCOV_EXCL_STOP
                // step 2: write the string
                oa->write_characters(
                    reinterpret_cast<const CharType *>(j.m_value.string->c_str()),
                    j.m_value.string->size());
                break;
            }
 
            case value_t::array:
            {
                // step 1: write control byte and the array size
                const auto N = j.m_value.array->size();
 
                if (N <= 0x17)
                {
                    write_number(static_cast<std::uint8_t>(0x80 + N));
                }
 
                else if (N <= (std::numeric_limits<std::uint8_t>::max)())
                {
                    oa->write_character(to_char_type(0x98));
                    write_number(static_cast<std::uint8_t>(N));
                }
 
                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
                {
                    oa->write_character(to_char_type(0x99));
                    write_number(static_cast<std::uint16_t>(N));
                }
 
                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
                {
                    oa->write_character(to_char_type(0x9A));
                    write_number(static_cast<std::uint32_t>(N));
                }
 
                // LCOV_EXCL_START
                else if (N <= (std::numeric_limits<std::uint64_t>::max)())
                {
                    oa->write_character(to_char_type(0x9B));
                    write_number(static_cast<std::uint64_t>(N));
                }
 
                // LCOV_EXCL_STOP
 
                // step 2: write each element
                for (const auto &el : *j.m_value.array)
                {
                    write_cbor(el);
                }
 
                break;
            }
 
            case value_t::binary:
            {
                if (j.m_value.binary->has_subtype())
                {
                    if (j.m_value.binary->subtype() <= (std::numeric_limits<std::uint8_t>::max)())
                    {
                        write_number(static_cast<std::uint8_t>(0xd8));
                        write_number(static_cast<std::uint8_t>(j.m_value.binary->subtype()));
                    }
 
                    else if (j.m_value.binary->subtype() <= (std::numeric_limits<std::uint16_t>::max)())
                    {
                        write_number(static_cast<std::uint8_t>(0xd9));
                        write_number(static_cast<std::uint16_t>(j.m_value.binary->subtype()));
                    }
 
                    else if (j.m_value.binary->subtype() <= (std::numeric_limits<std::uint32_t>::max)())
                    {
                        write_number(static_cast<std::uint8_t>(0xda));
                        write_number(static_cast<std::uint32_t>(j.m_value.binary->subtype()));
                    }
 
                    else if (j.m_value.binary->subtype() <= (std::numeric_limits<std::uint64_t>::max)())
                    {
                        write_number(static_cast<std::uint8_t>(0xdb));
                        write_number(static_cast<std::uint64_t>(j.m_value.binary->subtype()));
                    }
                }
 
                // step 1: write control byte and the binary array size
                const auto N = j.m_value.binary->size();
 
                if (N <= 0x17)
                {
                    write_number(static_cast<std::uint8_t>(0x40 + N));
                }
 
                else if (N <= (std::numeric_limits<std::uint8_t>::max)())
                {
                    oa->write_character(to_char_type(0x58));
                    write_number(static_cast<std::uint8_t>(N));
                }
 
                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
                {
                    oa->write_character(to_char_type(0x59));
                    write_number(static_cast<std::uint16_t>(N));
                }
 
                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
                {
                    oa->write_character(to_char_type(0x5A));
                    write_number(static_cast<std::uint32_t>(N));
                }
 
                // LCOV_EXCL_START
                else if (N <= (std::numeric_limits<std::uint64_t>::max)())
                {
                    oa->write_character(to_char_type(0x5B));
                    write_number(static_cast<std::uint64_t>(N));
                }
 
                // LCOV_EXCL_STOP
                // step 2: write each element
                oa->write_characters(
                    reinterpret_cast<const CharType *>(j.m_value.binary->data()),
                    N);
                break;
            }
 
            case value_t::object:
            {
                // step 1: write control byte and the object size
                const auto N = j.m_value.object->size();
 
                if (N <= 0x17)
                {
                    write_number(static_cast<std::uint8_t>(0xA0 + N));
                }
 
                else if (N <= (std::numeric_limits<std::uint8_t>::max)())
                {
                    oa->write_character(to_char_type(0xB8));
                    write_number(static_cast<std::uint8_t>(N));
                }
 
                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
                {
                    oa->write_character(to_char_type(0xB9));
                    write_number(static_cast<std::uint16_t>(N));
                }
 
                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
                {
                    oa->write_character(to_char_type(0xBA));
                    write_number(static_cast<std::uint32_t>(N));
                }
 
                // LCOV_EXCL_START
                else if (N <= (std::numeric_limits<std::uint64_t>::max)())
                {
                    oa->write_character(to_char_type(0xBB));
                    write_number(static_cast<std::uint64_t>(N));
                }
 
                // LCOV_EXCL_STOP
 
                // step 2: write each element
                for (const auto &el : *j.m_value.object)
                {
                    write_cbor(el.first);
                    write_cbor(el.second);
                }
 
                break;
            }
 
            case value_t::discarded:
            default:
                break;
        }
    }