diff options
Diffstat (limited to 'include/lib/modernjson/detail/output/binary_writer.hpp')
| -rw-r--r-- | include/lib/modernjson/detail/output/binary_writer.hpp | 949 |
1 files changed, 949 insertions, 0 deletions
diff --git a/include/lib/modernjson/detail/output/binary_writer.hpp b/include/lib/modernjson/detail/output/binary_writer.hpp new file mode 100644 index 0000000..1726e0c --- /dev/null +++ b/include/lib/modernjson/detail/output/binary_writer.hpp @@ -0,0 +1,949 @@ +#pragma once + +#include <algorithm> // reverse +#include <array> // array +#include <cstdint> // uint8_t, uint16_t, uint32_t, uint64_t +#include <cstring> // memcpy +#include <limits> // numeric_limits + +#include <lib/modernjson/detail/input/binary_reader.hpp> +#include <lib/modernjson/detail/output/output_adapters.hpp> + +namespace nlohmann +{ +namespace detail +{ +/////////////////// +// binary writer // +/////////////////// + +/*! +@brief serialization to CBOR and MessagePack values +*/ +template<typename BasicJsonType, typename CharType> +class binary_writer +{ + public: + /*! + @brief create a binary writer + + @param[in] adapter output adapter to write to + */ + explicit binary_writer(output_adapter_t<CharType> adapter) : oa(adapter) + { + assert(oa); + } + + /*! + @brief[in] j JSON value to serialize + */ + void write_cbor(const BasicJsonType& j) + { + switch (j.type()) + { + case value_t::null: + { + oa->write_character(static_cast<CharType>(0xF6)); + break; + } + + case value_t::boolean: + { + oa->write_character(j.m_value.boolean + ? static_cast<CharType>(0xF5) + : static_cast<CharType>(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<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x18)); + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x19)); + write_number(static_cast<uint16_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x1A)); + write_number(static_cast<uint32_t>(j.m_value.number_integer)); + } + else + { + oa->write_character(static_cast<CharType>(0x1B)); + write_number(static_cast<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<uint8_t>(0x20 + positive_number)); + } + else if (positive_number <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x38)); + write_number(static_cast<uint8_t>(positive_number)); + } + else if (positive_number <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x39)); + write_number(static_cast<uint16_t>(positive_number)); + } + else if (positive_number <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x3A)); + write_number(static_cast<uint32_t>(positive_number)); + } + else + { + oa->write_character(static_cast<CharType>(0x3B)); + write_number(static_cast<uint64_t>(positive_number)); + } + } + break; + } + + case value_t::number_unsigned: + { + if (j.m_value.number_unsigned <= 0x17) + { + write_number(static_cast<uint8_t>(j.m_value.number_unsigned)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x18)); + write_number(static_cast<uint8_t>(j.m_value.number_unsigned)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x19)); + write_number(static_cast<uint16_t>(j.m_value.number_unsigned)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x1A)); + write_number(static_cast<uint32_t>(j.m_value.number_unsigned)); + } + else + { + oa->write_character(static_cast<CharType>(0x1B)); + write_number(static_cast<uint64_t>(j.m_value.number_unsigned)); + } + break; + } + + case value_t::number_float: + { + oa->write_character(get_cbor_float_prefix(j.m_value.number_float)); + write_number(j.m_value.number_float); + 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<uint8_t>(0x60 + N)); + } + else if (N <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x78)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x79)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x7A)); + write_number(static_cast<uint32_t>(N)); + } + // LCOV_EXCL_START + else if (N <= (std::numeric_limits<uint64_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x7B)); + write_number(static_cast<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<uint8_t>(0x80 + N)); + } + else if (N <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x98)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x99)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x9A)); + write_number(static_cast<uint32_t>(N)); + } + // LCOV_EXCL_START + else if (N <= (std::numeric_limits<uint64_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x9B)); + write_number(static_cast<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::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<uint8_t>(0xA0 + N)); + } + else if (N <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(static_cast<CharType>(0xB8)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(static_cast<CharType>(0xB9)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(static_cast<CharType>(0xBA)); + write_number(static_cast<uint32_t>(N)); + } + // LCOV_EXCL_START + else if (N <= (std::numeric_limits<uint64_t>::max)()) + { + oa->write_character(static_cast<CharType>(0xBB)); + write_number(static_cast<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; + } + + default: + break; + } + } + + /*! + @brief[in] j JSON value to serialize + */ + void write_msgpack(const BasicJsonType& j) + { + switch (j.type()) + { + case value_t::null: // nil + { + oa->write_character(static_cast<CharType>(0xC0)); + break; + } + + case value_t::boolean: // true and false + { + oa->write_character(j.m_value.boolean + ? static_cast<CharType>(0xC3) + : static_cast<CharType>(0xC2)); + break; + } + + case value_t::number_integer: + { + if (j.m_value.number_integer >= 0) + { + // MessagePack 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_unsigned < 128) + { + // positive fixnum + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)()) + { + // uint 8 + oa->write_character(static_cast<CharType>(0xCC)); + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint16_t>::max)()) + { + // uint 16 + oa->write_character(static_cast<CharType>(0xCD)); + write_number(static_cast<uint16_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint32_t>::max)()) + { + // uint 32 + oa->write_character(static_cast<CharType>(0xCE)); + write_number(static_cast<uint32_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint64_t>::max)()) + { + // uint 64 + oa->write_character(static_cast<CharType>(0xCF)); + write_number(static_cast<uint64_t>(j.m_value.number_integer)); + } + } + else + { + if (j.m_value.number_integer >= -32) + { + // negative fixnum + write_number(static_cast<int8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits<int8_t>::min)() and + j.m_value.number_integer <= (std::numeric_limits<int8_t>::max)()) + { + // int 8 + oa->write_character(static_cast<CharType>(0xD0)); + write_number(static_cast<int8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits<int16_t>::min)() and + j.m_value.number_integer <= (std::numeric_limits<int16_t>::max)()) + { + // int 16 + oa->write_character(static_cast<CharType>(0xD1)); + write_number(static_cast<int16_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits<int32_t>::min)() and + j.m_value.number_integer <= (std::numeric_limits<int32_t>::max)()) + { + // int 32 + oa->write_character(static_cast<CharType>(0xD2)); + write_number(static_cast<int32_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits<int64_t>::min)() and + j.m_value.number_integer <= (std::numeric_limits<int64_t>::max)()) + { + // int 64 + oa->write_character(static_cast<CharType>(0xD3)); + write_number(static_cast<int64_t>(j.m_value.number_integer)); + } + } + break; + } + + case value_t::number_unsigned: + { + if (j.m_value.number_unsigned < 128) + { + // positive fixnum + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)()) + { + // uint 8 + oa->write_character(static_cast<CharType>(0xCC)); + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint16_t>::max)()) + { + // uint 16 + oa->write_character(static_cast<CharType>(0xCD)); + write_number(static_cast<uint16_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint32_t>::max)()) + { + // uint 32 + oa->write_character(static_cast<CharType>(0xCE)); + write_number(static_cast<uint32_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint64_t>::max)()) + { + // uint 64 + oa->write_character(static_cast<CharType>(0xCF)); + write_number(static_cast<uint64_t>(j.m_value.number_integer)); + } + break; + } + + case value_t::number_float: + { + oa->write_character(get_msgpack_float_prefix(j.m_value.number_float)); + write_number(j.m_value.number_float); + break; + } + + case value_t::string: + { + // step 1: write control byte and the string length + const auto N = j.m_value.string->size(); + if (N <= 31) + { + // fixstr + write_number(static_cast<uint8_t>(0xA0 | N)); + } + else if (N <= (std::numeric_limits<uint8_t>::max)()) + { + // str 8 + oa->write_character(static_cast<CharType>(0xD9)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + // str 16 + oa->write_character(static_cast<CharType>(0xDA)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + // str 32 + oa->write_character(static_cast<CharType>(0xDB)); + write_number(static_cast<uint32_t>(N)); + } + + // 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 <= 15) + { + // fixarray + write_number(static_cast<uint8_t>(0x90 | N)); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + // array 16 + oa->write_character(static_cast<CharType>(0xDC)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + // array 32 + oa->write_character(static_cast<CharType>(0xDD)); + write_number(static_cast<uint32_t>(N)); + } + + // step 2: write each element + for (const auto& el : *j.m_value.array) + { + write_msgpack(el); + } + break; + } + + case value_t::object: + { + // step 1: write control byte and the object size + const auto N = j.m_value.object->size(); + if (N <= 15) + { + // fixmap + write_number(static_cast<uint8_t>(0x80 | (N & 0xF))); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + // map 16 + oa->write_character(static_cast<CharType>(0xDE)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + // map 32 + oa->write_character(static_cast<CharType>(0xDF)); + write_number(static_cast<uint32_t>(N)); + } + + // step 2: write each element + for (const auto& el : *j.m_value.object) + { + write_msgpack(el.first); + write_msgpack(el.second); + } + break; + } + + default: + break; + } + } + + /*! + @param[in] j JSON value to serialize + @param[in] use_count whether to use '#' prefixes (optimized format) + @param[in] use_type whether to use '$' prefixes (optimized format) + @param[in] add_prefix whether prefixes need to be used for this value + */ + void write_ubjson(const BasicJsonType& j, const bool use_count, + const bool use_type, const bool add_prefix = true) + { + switch (j.type()) + { + case value_t::null: + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('Z')); + } + break; + } + + case value_t::boolean: + { + if (add_prefix) + oa->write_character(j.m_value.boolean + ? static_cast<CharType>('T') + : static_cast<CharType>('F')); + break; + } + + case value_t::number_integer: + { + write_number_with_ubjson_prefix(j.m_value.number_integer, add_prefix); + break; + } + + case value_t::number_unsigned: + { + write_number_with_ubjson_prefix(j.m_value.number_unsigned, add_prefix); + break; + } + + case value_t::number_float: + { + write_number_with_ubjson_prefix(j.m_value.number_float, add_prefix); + break; + } + + case value_t::string: + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('S')); + } + write_number_with_ubjson_prefix(j.m_value.string->size(), true); + oa->write_characters( + reinterpret_cast<const CharType*>(j.m_value.string->c_str()), + j.m_value.string->size()); + break; + } + + case value_t::array: + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('[')); + } + + bool prefix_required = true; + if (use_type and not j.m_value.array->empty()) + { + assert(use_count); + const CharType first_prefix = ubjson_prefix(j.front()); + const bool same_prefix = std::all_of(j.begin() + 1, j.end(), + [this, first_prefix](const BasicJsonType & v) + { + return ubjson_prefix(v) == first_prefix; + }); + + if (same_prefix) + { + prefix_required = false; + oa->write_character(static_cast<CharType>('$')); + oa->write_character(first_prefix); + } + } + + if (use_count) + { + oa->write_character(static_cast<CharType>('#')); + write_number_with_ubjson_prefix(j.m_value.array->size(), true); + } + + for (const auto& el : *j.m_value.array) + { + write_ubjson(el, use_count, use_type, prefix_required); + } + + if (not use_count) + { + oa->write_character(static_cast<CharType>(']')); + } + + break; + } + + case value_t::object: + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('{')); + } + + bool prefix_required = true; + if (use_type and not j.m_value.object->empty()) + { + assert(use_count); + const CharType first_prefix = ubjson_prefix(j.front()); + const bool same_prefix = std::all_of(j.begin(), j.end(), + [this, first_prefix](const BasicJsonType & v) + { + return ubjson_prefix(v) == first_prefix; + }); + + if (same_prefix) + { + prefix_required = false; + oa->write_character(static_cast<CharType>('$')); + oa->write_character(first_prefix); + } + } + + if (use_count) + { + oa->write_character(static_cast<CharType>('#')); + write_number_with_ubjson_prefix(j.m_value.object->size(), true); + } + + for (const auto& el : *j.m_value.object) + { + write_number_with_ubjson_prefix(el.first.size(), true); + oa->write_characters( + reinterpret_cast<const CharType*>(el.first.c_str()), + el.first.size()); + write_ubjson(el.second, use_count, use_type, prefix_required); + } + + if (not use_count) + { + oa->write_character(static_cast<CharType>('}')); + } + + break; + } + + default: + break; + } + } + + private: + /* + @brief write a number to output input + + @param[in] n number of type @a NumberType + @tparam NumberType the type of the number + + @note This function needs to respect the system's endianess, because bytes + in CBOR, MessagePack, and UBJSON are stored in network order (big + endian) and therefore need reordering on little endian systems. + */ + template<typename NumberType> + void write_number(const NumberType n) + { + // step 1: write number to array of length NumberType + std::array<CharType, sizeof(NumberType)> vec; + std::memcpy(vec.data(), &n, sizeof(NumberType)); + + // step 2: write array to output (with possible reordering) + if (is_little_endian) + { + // reverse byte order prior to conversion if necessary + std::reverse(vec.begin(), vec.end()); + } + + oa->write_characters(vec.data(), sizeof(NumberType)); + } + + // UBJSON: write number (floating point) + template<typename NumberType, typename std::enable_if< + std::is_floating_point<NumberType>::value, int>::type = 0> + void write_number_with_ubjson_prefix(const NumberType n, + const bool add_prefix) + { + if (add_prefix) + { + oa->write_character(get_ubjson_float_prefix(n)); + } + write_number(n); + } + + // UBJSON: write number (unsigned integer) + template<typename NumberType, typename std::enable_if< + std::is_unsigned<NumberType>::value, int>::type = 0> + void write_number_with_ubjson_prefix(const NumberType n, + const bool add_prefix) + { + if (n <= static_cast<uint64_t>((std::numeric_limits<int8_t>::max)())) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('i')); // int8 + } + write_number(static_cast<uint8_t>(n)); + } + else if (n <= (std::numeric_limits<uint8_t>::max)()) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('U')); // uint8 + } + write_number(static_cast<uint8_t>(n)); + } + else if (n <= static_cast<uint64_t>((std::numeric_limits<int16_t>::max)())) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('I')); // int16 + } + write_number(static_cast<int16_t>(n)); + } + else if (n <= static_cast<uint64_t>((std::numeric_limits<int32_t>::max)())) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('l')); // int32 + } + write_number(static_cast<int32_t>(n)); + } + else if (n <= static_cast<uint64_t>((std::numeric_limits<int64_t>::max)())) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('L')); // int64 + } + write_number(static_cast<int64_t>(n)); + } + else + { + JSON_THROW(out_of_range::create(407, "number overflow serializing " + std::to_string(n))); + } + } + + // UBJSON: write number (signed integer) + template<typename NumberType, typename std::enable_if< + std::is_signed<NumberType>::value and + not std::is_floating_point<NumberType>::value, int>::type = 0> + void write_number_with_ubjson_prefix(const NumberType n, + const bool add_prefix) + { + if ((std::numeric_limits<int8_t>::min)() <= n and n <= (std::numeric_limits<int8_t>::max)()) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('i')); // int8 + } + write_number(static_cast<int8_t>(n)); + } + else if (static_cast<int64_t>((std::numeric_limits<uint8_t>::min)()) <= n and n <= static_cast<int64_t>((std::numeric_limits<uint8_t>::max)())) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('U')); // uint8 + } + write_number(static_cast<uint8_t>(n)); + } + else if ((std::numeric_limits<int16_t>::min)() <= n and n <= (std::numeric_limits<int16_t>::max)()) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('I')); // int16 + } + write_number(static_cast<int16_t>(n)); + } + else if ((std::numeric_limits<int32_t>::min)() <= n and n <= (std::numeric_limits<int32_t>::max)()) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('l')); // int32 + } + write_number(static_cast<int32_t>(n)); + } + else if ((std::numeric_limits<int64_t>::min)() <= n and n <= (std::numeric_limits<int64_t>::max)()) + { + if (add_prefix) + { + oa->write_character(static_cast<CharType>('L')); // int64 + } + write_number(static_cast<int64_t>(n)); + } + // LCOV_EXCL_START + else + { + JSON_THROW(out_of_range::create(407, "number overflow serializing " + std::to_string(n))); + } + // LCOV_EXCL_STOP + } + + /*! + @brief determine the type prefix of container values + + @note This function does not need to be 100% accurate when it comes to + integer limits. In case a number exceeds the limits of int64_t, + this will be detected by a later call to function + write_number_with_ubjson_prefix. Therefore, we return 'L' for any + value that does not fit the previous limits. + */ + CharType ubjson_prefix(const BasicJsonType& j) const noexcept + { + switch (j.type()) + { + case value_t::null: + return 'Z'; + + case value_t::boolean: + return j.m_value.boolean ? 'T' : 'F'; + + case value_t::number_integer: + { + if ((std::numeric_limits<int8_t>::min)() <= j.m_value.number_integer and j.m_value.number_integer <= (std::numeric_limits<int8_t>::max)()) + { + return 'i'; + } + else if ((std::numeric_limits<uint8_t>::min)() <= j.m_value.number_integer and j.m_value.number_integer <= (std::numeric_limits<uint8_t>::max)()) + { + return 'U'; + } + else if ((std::numeric_limits<int16_t>::min)() <= j.m_value.number_integer and j.m_value.number_integer <= (std::numeric_limits<int16_t>::max)()) + { + return 'I'; + } + else if ((std::numeric_limits<int32_t>::min)() <= j.m_value.number_integer and j.m_value.number_integer <= (std::numeric_limits<int32_t>::max)()) + { + return 'l'; + } + else // no check and assume int64_t (see note above) + { + return 'L'; + } + } + + case value_t::number_unsigned: + { + if (j.m_value.number_unsigned <= (std::numeric_limits<int8_t>::max)()) + { + return 'i'; + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)()) + { + return 'U'; + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<int16_t>::max)()) + { + return 'I'; + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<int32_t>::max)()) + { + return 'l'; + } + else // no check and assume int64_t (see note above) + { + return 'L'; + } + } + + case value_t::number_float: + return get_ubjson_float_prefix(j.m_value.number_float); + + case value_t::string: + return 'S'; + + case value_t::array: + return '['; + + case value_t::object: + return '{'; + + default: // discarded values + return 'N'; + } + } + + static constexpr CharType get_cbor_float_prefix(float) + { + return static_cast<CharType>(0xFA); // Single-Precision Float + } + + static constexpr CharType get_cbor_float_prefix(double) + { + return static_cast<CharType>(0xFB); // Double-Precision Float + } + + static constexpr CharType get_msgpack_float_prefix(float) + { + return static_cast<CharType>(0xCA); // float 32 + } + + static constexpr CharType get_msgpack_float_prefix(double) + { + return static_cast<CharType>(0xCB); // float 64 + } + + static constexpr CharType get_ubjson_float_prefix(float) + { + return 'd'; // float 32 + } + + static constexpr CharType get_ubjson_float_prefix(double) + { + return 'D'; // float 64 + } + + private: + /// whether we can assume little endianess + const bool is_little_endian = binary_reader<BasicJsonType>::little_endianess(); + + /// the output + output_adapter_t<CharType> oa = nullptr; +}; +} +} |