#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 "detail/parsing/binary_reader.hpp"
#include "detail/parsing/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: // Double-Precision Float
{
oa->write_character(static_cast<CharType>(0xFB));
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 <= 0xFF)
{
oa->write_character(static_cast<CharType>(0x78));
write_number(static_cast<uint8_t>(N));
}
else if (N <= 0xFFFF)
{
oa->write_character(static_cast<CharType>(0x79));
write_number(static_cast<uint16_t>(N));
}
else if (N <= 0xFFFFFFFF)
{
oa->write_character(static_cast<CharType>(0x7A));
write_number(static_cast<uint32_t>(N));
}
// LCOV_EXCL_START
else if (N <= 0xFFFFFFFFFFFFFFFF)
{
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 <= 0xFF)
{
oa->write_character(static_cast<CharType>(0x98));
write_number(static_cast<uint8_t>(N));
}
else if (N <= 0xFFFF)
{
oa->write_character(static_cast<CharType>(0x99));
write_number(static_cast<uint16_t>(N));
}
else if (N <= 0xFFFFFFFF)
{
oa->write_character(static_cast<CharType>(0x9A));
write_number(static_cast<uint32_t>(N));
}
// LCOV_EXCL_START
else if (N <= 0xFFFFFFFFFFFFFFFF)
{
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 <= 0xFF)
{
oa->write_character(static_cast<CharType>(0xB8));
write_number(static_cast<uint8_t>(N));
}
else if (N <= 0xFFFF)
{
oa->write_character(static_cast<CharType>(0xB9));
write_number(static_cast<uint16_t>(N));
}
else if (N <= 0xFFFFFFFF)
{
oa->write_character(static_cast<CharType>(0xBA));
write_number(static_cast<uint32_t>(N));
}
// LCOV_EXCL_START
else if (N <= 0xFFFFFFFFFFFFFFFF)
{
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: // float 64
{
oa->write_character(static_cast<CharType>(0xCB));
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 <= 255)
{
// str 8
oa->write_character(static_cast<CharType>(0xD9));
write_number(static_cast<uint8_t>(N));
}
else if (N <= 65535)
{
// str 16
oa->write_character(static_cast<CharType>(0xDA));
write_number(static_cast<uint16_t>(N));
}
else if (N <= 4294967295)
{
// 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 <= 0xFFFF)
{
// array 16
oa->write_character(static_cast<CharType>(0xDC));
write_number(static_cast<uint16_t>(N));
}
else if (N <= 0xFFFFFFFF)
{
// 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 <= 65535)
{
// map 16
oa->write_character(static_cast<CharType>(0xDE));
write_number(static_cast<uint16_t>(N));
}
else if (N <= 4294967295)
{
// 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;
}
}
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 and MessagePack are stored in network order (big endian) and
therefore need reordering on little endian systems.
*/
template<typename NumberType> void write_number(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));
}
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;
};
}
}