diff options
Diffstat (limited to 'include/lib/modernjson/detail/output/binary_writer.hpp')
-rw-r--r-- | include/lib/modernjson/detail/output/binary_writer.hpp | 1339 |
1 files changed, 1339 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..1020e69 --- /dev/null +++ b/include/lib/modernjson/detail/output/binary_writer.hpp @@ -0,0 +1,1339 @@ +#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 +{ + using string_t = typename BasicJsonType::string_t; + + 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); + } + + /*! + @param[in] j JSON value to serialize + @pre j.type() == value_t::object + */ + void write_bson(const BasicJsonType& j) + { + switch (j.type()) + { + case value_t::object: + { + write_bson_object(*j.m_value.object); + break; + } + + default: + { + JSON_THROW(type_error::create(317, "to serialize to BSON, top-level type must be object, but is " + std::string(j.type_name()))); + } + } + } + + /*! + @param[in] j JSON value to serialize + */ + void write_cbor(const BasicJsonType& j) + { + 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<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(to_char_type(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(to_char_type(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(to_char_type(0x1A)); + write_number(static_cast<uint32_t>(j.m_value.number_integer)); + } + else + { + oa->write_character(to_char_type(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(to_char_type(0x38)); + write_number(static_cast<uint8_t>(positive_number)); + } + else if (positive_number <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(to_char_type(0x39)); + write_number(static_cast<uint16_t>(positive_number)); + } + else if (positive_number <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(to_char_type(0x3A)); + write_number(static_cast<uint32_t>(positive_number)); + } + else + { + oa->write_character(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(0x1A)); + write_number(static_cast<uint32_t>(j.m_value.number_unsigned)); + } + else + { + oa->write_character(to_char_type(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(to_char_type(0x78)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(to_char_type(0x79)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(to_char_type(0x7A)); + write_number(static_cast<uint32_t>(N)); + } + // LCOV_EXCL_START + else if (N <= (std::numeric_limits<uint64_t>::max)()) + { + oa->write_character(to_char_type(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(to_char_type(0x98)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(to_char_type(0x99)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(to_char_type(0x9A)); + write_number(static_cast<uint32_t>(N)); + } + // LCOV_EXCL_START + else if (N <= (std::numeric_limits<uint64_t>::max)()) + { + oa->write_character(to_char_type(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(to_char_type(0xB8)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(to_char_type(0xB9)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(to_char_type(0xBA)); + write_number(static_cast<uint32_t>(N)); + } + // LCOV_EXCL_START + else if (N <= (std::numeric_limits<uint64_t>::max)()) + { + oa->write_character(to_char_type(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; + } + } + + /*! + @param[in] j JSON value to serialize + */ + void write_msgpack(const BasicJsonType& j) + { + switch (j.type()) + { + case value_t::null: // nil + { + oa->write_character(to_char_type(0xC0)); + break; + } + + case value_t::boolean: // true and false + { + oa->write_character(j.m_value.boolean + ? to_char_type(0xC3) + : to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(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(to_char_type(0xD9)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= (std::numeric_limits<uint16_t>::max)()) + { + // str 16 + oa->write_character(to_char_type(0xDA)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + // str 32 + oa->write_character(to_char_type(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(to_char_type(0xDC)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + // array 32 + oa->write_character(to_char_type(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(to_char_type(0xDE)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= (std::numeric_limits<uint32_t>::max)()) + { + // map 32 + oa->write_character(to_char_type(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 '$' prefixes (optimized format) + @param[in] add_prefix whether prefixes need to be used for this value + */ + void write_ubjson(const BasicJsonType& j, const bool use_count, + const bool use_type, const bool add_prefix = true) + { + switch (j.type()) + { + case value_t::null: + { + if (add_prefix) + { + oa->write_character(to_char_type('Z')); + } + break; + } + + case value_t::boolean: + { + if (add_prefix) + { + oa->write_character(j.m_value.boolean + ? to_char_type('T') + : to_char_type('F')); + } + break; + } + + case value_t::number_integer: + { + write_number_with_ubjson_prefix(j.m_value.number_integer, add_prefix); + break; + } + + case value_t::number_unsigned: + { + write_number_with_ubjson_prefix(j.m_value.number_unsigned, add_prefix); + break; + } + + case value_t::number_float: + { + write_number_with_ubjson_prefix(j.m_value.number_float, add_prefix); + break; + } + + case value_t::string: + { + if (add_prefix) + { + oa->write_character(to_char_type('S')); + } + write_number_with_ubjson_prefix(j.m_value.string->size(), true); + oa->write_characters( + reinterpret_cast<const CharType*>(j.m_value.string->c_str()), + j.m_value.string->size()); + break; + } + + case value_t::array: + { + if (add_prefix) + { + oa->write_character(to_char_type('[')); + } + + bool prefix_required = true; + if (use_type and not j.m_value.array->empty()) + { + assert(use_count); + const CharType first_prefix = ubjson_prefix(j.front()); + const bool same_prefix = std::all_of(j.begin() + 1, j.end(), + [this, first_prefix](const BasicJsonType & v) + { + return ubjson_prefix(v) == first_prefix; + }); + + if (same_prefix) + { + prefix_required = false; + oa->write_character(to_char_type('$')); + oa->write_character(first_prefix); + } + } + + if (use_count) + { + oa->write_character(to_char_type('#')); + 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(to_char_type(']')); + } + + break; + } + + case value_t::object: + { + if (add_prefix) + { + oa->write_character(to_char_type('{')); + } + + 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(to_char_type('$')); + oa->write_character(first_prefix); + } + } + + if (use_count) + { + oa->write_character(to_char_type('#')); + 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(to_char_type('}')); + } + + break; + } + + default: + break; + } + } + + private: + ////////// + // BSON // + ////////// + + /*! + @return The size of a BSON document entry header, including the id marker + and the entry name size (and its null-terminator). + */ + static std::size_t calc_bson_entry_header_size(const string_t& name) + { + const auto it = name.find(static_cast<typename string_t::value_type>(0)); + if (JSON_UNLIKELY(it != BasicJsonType::string_t::npos)) + { + JSON_THROW(out_of_range::create(409, + "BSON key cannot contain code point U+0000 (at byte " + std::to_string(it) + ")")); + } + + return /*id*/ 1ul + name.size() + /*zero-terminator*/1u; + } + + /*! + @brief Writes the given @a element_type and @a name to the output adapter + */ + void write_bson_entry_header(const string_t& name, + const std::uint8_t element_type) + { + oa->write_character(to_char_type(element_type)); // boolean + oa->write_characters( + reinterpret_cast<const CharType*>(name.c_str()), + name.size() + 1u); + } + + /*! + @brief Writes a BSON element with key @a name and boolean value @a value + */ + void write_bson_boolean(const string_t& name, + const bool value) + { + write_bson_entry_header(name, 0x08); + oa->write_character(value ? to_char_type(0x01) : to_char_type(0x00)); + } + + /*! + @brief Writes a BSON element with key @a name and double value @a value + */ + void write_bson_double(const string_t& name, + const double value) + { + write_bson_entry_header(name, 0x01); + write_number<double, true>(value); + } + + /*! + @return The size of the BSON-encoded string in @a value + */ + static std::size_t calc_bson_string_size(const string_t& value) + { + return sizeof(std::int32_t) + value.size() + 1ul; + } + + /*! + @brief Writes a BSON element with key @a name and string value @a value + */ + void write_bson_string(const string_t& name, + const string_t& value) + { + write_bson_entry_header(name, 0x02); + + write_number<std::int32_t, true>(static_cast<std::int32_t>(value.size() + 1ul)); + oa->write_characters( + reinterpret_cast<const CharType*>(value.c_str()), + value.size() + 1); + } + + /*! + @brief Writes a BSON element with key @a name and null value + */ + void write_bson_null(const string_t& name) + { + write_bson_entry_header(name, 0x0A); + } + + /*! + @return The size of the BSON-encoded integer @a value + */ + static std::size_t calc_bson_integer_size(const std::int64_t value) + { + if ((std::numeric_limits<std::int32_t>::min)() <= value and value <= (std::numeric_limits<std::int32_t>::max)()) + { + return sizeof(std::int32_t); + } + else + { + return sizeof(std::int64_t); + } + } + + /*! + @brief Writes a BSON element with key @a name and integer @a value + */ + void write_bson_integer(const string_t& name, + const std::int64_t value) + { + if ((std::numeric_limits<std::int32_t>::min)() <= value and value <= (std::numeric_limits<std::int32_t>::max)()) + { + write_bson_entry_header(name, 0x10); // int32 + write_number<std::int32_t, true>(static_cast<std::int32_t>(value)); + } + else + { + write_bson_entry_header(name, 0x12); // int64 + write_number<std::int64_t, true>(static_cast<std::int64_t>(value)); + } + } + + /*! + @return The size of the BSON-encoded unsigned integer in @a j + */ + static constexpr std::size_t calc_bson_unsigned_size(const std::uint64_t value) noexcept + { + return (value <= static_cast<std::uint64_t>((std::numeric_limits<std::int32_t>::max)())) + ? sizeof(std::int32_t) + : sizeof(std::int64_t); + } + + /*! + @brief Writes a BSON element with key @a name and unsigned @a value + */ + void write_bson_unsigned(const string_t& name, + const std::uint64_t value) + { + if (value <= static_cast<std::uint64_t>((std::numeric_limits<std::int32_t>::max)())) + { + write_bson_entry_header(name, 0x10 /* int32 */); + write_number<std::int32_t, true>(static_cast<std::int32_t>(value)); + } + else if (value <= static_cast<std::uint64_t>((std::numeric_limits<std::int64_t>::max)())) + { + write_bson_entry_header(name, 0x12 /* int64 */); + write_number<std::int64_t, true>(static_cast<std::int64_t>(value)); + } + else + { + JSON_THROW(out_of_range::create(407, "integer number " + std::to_string(value) + " cannot be represented by BSON as it does not fit int64")); + } + } + + /*! + @brief Writes a BSON element with key @a name and object @a value + */ + void write_bson_object_entry(const string_t& name, + const typename BasicJsonType::object_t& value) + { + write_bson_entry_header(name, 0x03); // object + write_bson_object(value); + } + + /*! + @return The size of the BSON-encoded array @a value + */ + static std::size_t calc_bson_array_size(const typename BasicJsonType::array_t& value) + { + std::size_t embedded_document_size = 0ul; + std::size_t array_index = 0ul; + + for (const auto& el : value) + { + embedded_document_size += calc_bson_element_size(std::to_string(array_index++), el); + } + + return sizeof(std::int32_t) + embedded_document_size + 1ul; + } + + /*! + @brief Writes a BSON element with key @a name and array @a value + */ + void write_bson_array(const string_t& name, + const typename BasicJsonType::array_t& value) + { + write_bson_entry_header(name, 0x04); // array + write_number<std::int32_t, true>(static_cast<std::int32_t>(calc_bson_array_size(value))); + + std::size_t array_index = 0ul; + + for (const auto& el : value) + { + write_bson_element(std::to_string(array_index++), el); + } + + oa->write_character(to_char_type(0x00)); + } + + /*! + @brief Calculates the size necessary to serialize the JSON value @a j with its @a name + @return The calculated size for the BSON document entry for @a j with the given @a name. + */ + static std::size_t calc_bson_element_size(const string_t& name, + const BasicJsonType& j) + { + const auto header_size = calc_bson_entry_header_size(name); + switch (j.type()) + { + case value_t::object: + return header_size + calc_bson_object_size(*j.m_value.object); + + case value_t::array: + return header_size + calc_bson_array_size(*j.m_value.array); + + case value_t::boolean: + return header_size + 1ul; + + case value_t::number_float: + return header_size + 8ul; + + case value_t::number_integer: + return header_size + calc_bson_integer_size(j.m_value.number_integer); + + case value_t::number_unsigned: + return header_size + calc_bson_unsigned_size(j.m_value.number_unsigned); + + case value_t::string: + return header_size + calc_bson_string_size(*j.m_value.string); + + case value_t::null: + return header_size + 0ul; + + // LCOV_EXCL_START + default: + assert(false); + return 0ul; + // LCOV_EXCL_STOP + }; + } + + /*! + @brief Serializes the JSON value @a j to BSON and associates it with the + key @a name. + @param name The name to associate with the JSON entity @a j within the + current BSON document + @return The size of the BSON entry + */ + void write_bson_element(const string_t& name, + const BasicJsonType& j) + { + switch (j.type()) + { + case value_t::object: + return write_bson_object_entry(name, *j.m_value.object); + + case value_t::array: + return write_bson_array(name, *j.m_value.array); + + case value_t::boolean: + return write_bson_boolean(name, j.m_value.boolean); + + case value_t::number_float: + return write_bson_double(name, j.m_value.number_float); + + case value_t::number_integer: + return write_bson_integer(name, j.m_value.number_integer); + + case value_t::number_unsigned: + return write_bson_unsigned(name, j.m_value.number_unsigned); + + case value_t::string: + return write_bson_string(name, *j.m_value.string); + + case value_t::null: + return write_bson_null(name); + + // LCOV_EXCL_START + default: + assert(false); + return; + // LCOV_EXCL_STOP + }; + } + + /*! + @brief Calculates the size of the BSON serialization of the given + JSON-object @a j. + @param[in] j JSON value to serialize + @pre j.type() == value_t::object + */ + static std::size_t calc_bson_object_size(const typename BasicJsonType::object_t& value) + { + std::size_t document_size = std::accumulate(value.begin(), value.end(), 0ul, + [](size_t result, const typename BasicJsonType::object_t::value_type & el) + { + return result += calc_bson_element_size(el.first, el.second); + }); + + return sizeof(std::int32_t) + document_size + 1ul; + } + + /*! + @param[in] j JSON value to serialize + @pre j.type() == value_t::object + */ + void write_bson_object(const typename BasicJsonType::object_t& value) + { + write_number<std::int32_t, true>(static_cast<std::int32_t>(calc_bson_object_size(value))); + + for (const auto& el : value) + { + write_bson_element(el.first, el.second); + } + + oa->write_character(to_char_type(0x00)); + } + + ////////// + // CBOR // + ////////// + + static constexpr CharType get_cbor_float_prefix(float /*unused*/) + { + return to_char_type(0xFA); // Single-Precision Float + } + + static constexpr CharType get_cbor_float_prefix(double /*unused*/) + { + return to_char_type(0xFB); // Double-Precision Float + } + + ///////////// + // MsgPack // + ///////////// + + static constexpr CharType get_msgpack_float_prefix(float /*unused*/) + { + return to_char_type(0xCA); // float 32 + } + + static constexpr CharType get_msgpack_float_prefix(double /*unused*/) + { + return to_char_type(0xCB); // float 64 + } + + //////////// + // UBJSON // + //////////// + + // 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(to_char_type('i')); // int8 + } + write_number(static_cast<uint8_t>(n)); + } + else if (n <= (std::numeric_limits<uint8_t>::max)()) + { + if (add_prefix) + { + oa->write_character(to_char_type('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(to_char_type('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(to_char_type('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(to_char_type('L')); // int64 + } + write_number(static_cast<int64_t>(n)); + } + else + { + JSON_THROW(out_of_range::create(407, "integer number " + std::to_string(n) + " cannot be represented by UBJSON as it does not fit int64")); + } + } + + // 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(to_char_type('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(to_char_type('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(to_char_type('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(to_char_type('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(to_char_type('L')); // int64 + } + write_number(static_cast<int64_t>(n)); + } + // LCOV_EXCL_START + else + { + JSON_THROW(out_of_range::create(407, "integer number " + std::to_string(n) + " cannot be represented by UBJSON as it does not fit int64")); + } + // 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'; + } + 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'; + } + 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'; + } + 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'; + } + // 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'; + } + if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)()) + { + return 'U'; + } + if (j.m_value.number_unsigned <= (std::numeric_limits<int16_t>::max)()) + { + return 'I'; + } + if (j.m_value.number_unsigned <= (std::numeric_limits<int32_t>::max)()) + { + return 'l'; + } + // 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_ubjson_float_prefix(float /*unused*/) + { + return 'd'; // float 32 + } + + static constexpr CharType get_ubjson_float_prefix(double /*unused*/) + { + return 'D'; // float 64 + } + + /////////////////////// + // Utility functions // + /////////////////////// + + /* + @brief write a number to output input + @param[in] n number of type @a NumberType + @tparam NumberType the type of the number + @tparam OutputIsLittleEndian Set to true if output data is + required to be little endian + + @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, bool OutputIsLittleEndian = false> + 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 and not OutputIsLittleEndian) + { + // reverse byte order prior to conversion if necessary + std::reverse(vec.begin(), vec.end()); + } + + oa->write_characters(vec.data(), sizeof(NumberType)); + } + + public: + // The following to_char_type functions are implement the conversion + // between uint8_t and CharType. In case CharType is not unsigned, + // such a conversion is required to allow values greater than 128. + // See <https://github.com/nlohmann/json/issues/1286> for a discussion. + template < typename C = CharType, + enable_if_t < std::is_signed<C>::value and std::is_signed<char>::value > * = nullptr > + static constexpr CharType to_char_type(std::uint8_t x) noexcept + { + return *reinterpret_cast<char*>(&x); + } + + template < typename C = CharType, + enable_if_t < std::is_signed<C>::value and std::is_unsigned<char>::value > * = nullptr > + static CharType to_char_type(std::uint8_t x) noexcept + { + static_assert(sizeof(std::uint8_t) == sizeof(CharType), "size of CharType must be equal to std::uint8_t"); + static_assert(std::is_pod<CharType>::value, "CharType must be POD"); + CharType result; + std::memcpy(&result, &x, sizeof(x)); + return result; + } + + template<typename C = CharType, + enable_if_t<std::is_unsigned<C>::value>* = nullptr> + static constexpr CharType to_char_type(std::uint8_t x) noexcept + { + return x; + } + + template < typename InputCharType, typename C = CharType, + enable_if_t < + std::is_signed<C>::value and + std::is_signed<char>::value and + std::is_same<char, typename std::remove_cv<InputCharType>::type>::value + > * = nullptr > + static constexpr CharType to_char_type(InputCharType x) noexcept + { + return x; + } + + 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; +}; +} // namespace detail +} // namespace nlohmann |