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diff --git a/include/lib/modernjson/detail/input/binary_reader.hpp b/include/lib/modernjson/detail/input/binary_reader.hpp
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+++ b/include/lib/modernjson/detail/input/binary_reader.hpp
@@ -0,0 +1,1984 @@
+#pragma once
+
+#include <algorithm> // generate_n
+#include <array> // array
+#include <cassert> // assert
+#include <cmath> // ldexp
+#include <cstddef> // size_t
+#include <cstdint> // uint8_t, uint16_t, uint32_t, uint64_t
+#include <cstdio> // snprintf
+#include <cstring> // memcpy
+#include <iterator> // back_inserter
+#include <limits> // numeric_limits
+#include <string> // char_traits, string
+#include <utility> // make_pair, move
+
+#include <lib/modernjson/detail/input/input_adapters.hpp>
+#include <lib/modernjson/detail/input/json_sax.hpp>
+#include <lib/modernjson/detail/exceptions.hpp>
+#include <lib/modernjson/detail/macro_scope.hpp>
+#include <lib/modernjson/detail/meta/is_sax.hpp>
+#include <lib/modernjson/detail/value_t.hpp>
+
+namespace nlohmann
+{
+namespace detail
+{
+///////////////////
+// binary reader //
+///////////////////
+
+/*!
+@brief deserialization of CBOR, MessagePack, and UBJSON values
+*/
+template<typename BasicJsonType, typename SAX = json_sax_dom_parser<BasicJsonType>>
+class binary_reader
+{
+ using number_integer_t = typename BasicJsonType::number_integer_t;
+ using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+ using number_float_t = typename BasicJsonType::number_float_t;
+ using string_t = typename BasicJsonType::string_t;
+ using json_sax_t = SAX;
+
+ public:
+ /*!
+ @brief create a binary reader
+
+ @param[in] adapter input adapter to read from
+ */
+ explicit binary_reader(input_adapter_t adapter) : ia(std::move(adapter))
+ {
+ (void)detail::is_sax_static_asserts<SAX, BasicJsonType> {};
+ assert(ia);
+ }
+
+ /*!
+ @param[in] format the binary format to parse
+ @param[in] sax_ a SAX event processor
+ @param[in] strict whether to expect the input to be consumed completed
+
+ @return
+ */
+ bool sax_parse(const input_format_t format,
+ json_sax_t* sax_,
+ const bool strict = true)
+ {
+ sax = sax_;
+ bool result = false;
+
+ switch (format)
+ {
+ case input_format_t::bson:
+ result = parse_bson_internal();
+ break;
+
+ case input_format_t::cbor:
+ result = parse_cbor_internal();
+ break;
+
+ case input_format_t::msgpack:
+ result = parse_msgpack_internal();
+ break;
+
+ case input_format_t::ubjson:
+ result = parse_ubjson_internal();
+ break;
+
+ // LCOV_EXCL_START
+ default:
+ assert(false);
+ // LCOV_EXCL_STOP
+ }
+
+ // strict mode: next byte must be EOF
+ if (result and strict)
+ {
+ if (format == input_format_t::ubjson)
+ {
+ get_ignore_noop();
+ }
+ else
+ {
+ get();
+ }
+
+ if (JSON_UNLIKELY(current != std::char_traits<char>::eof()))
+ {
+ return sax->parse_error(chars_read, get_token_string(),
+ parse_error::create(110, chars_read, exception_message(format, "expected end of input; last byte: 0x" + get_token_string(), "value")));
+ }
+ }
+
+ return result;
+ }
+
+ /*!
+ @brief determine system byte order
+
+ @return true if and only if system's byte order is little endian
+
+ @note from http://stackoverflow.com/a/1001328/266378
+ */
+ static constexpr bool little_endianess(int num = 1) noexcept
+ {
+ return (*reinterpret_cast<char*>(&num) == 1);
+ }
+
+ private:
+ //////////
+ // BSON //
+ //////////
+
+ /*!
+ @brief Reads in a BSON-object and passes it to the SAX-parser.
+ @return whether a valid BSON-value was passed to the SAX parser
+ */
+ bool parse_bson_internal()
+ {
+ std::int32_t document_size;
+ get_number<std::int32_t, true>(input_format_t::bson, document_size);
+
+ if (JSON_UNLIKELY(not sax->start_object(std::size_t(-1))))
+ {
+ return false;
+ }
+
+ if (JSON_UNLIKELY(not parse_bson_element_list(/*is_array*/false)))
+ {
+ return false;
+ }
+
+ return sax->end_object();
+ }
+
+ /*!
+ @brief Parses a C-style string from the BSON input.
+ @param[in, out] result A reference to the string variable where the read
+ string is to be stored.
+ @return `true` if the \x00-byte indicating the end of the string was
+ encountered before the EOF; false` indicates an unexpected EOF.
+ */
+ bool get_bson_cstr(string_t& result)
+ {
+ auto out = std::back_inserter(result);
+ while (true)
+ {
+ get();
+ if (JSON_UNLIKELY(not unexpect_eof(input_format_t::bson, "cstring")))
+ {
+ return false;
+ }
+ if (current == 0x00)
+ {
+ return true;
+ }
+ *out++ = static_cast<char>(current);
+ }
+
+ return true;
+ }
+
+ /*!
+ @brief Parses a zero-terminated string of length @a len from the BSON
+ input.
+ @param[in] len The length (including the zero-byte at the end) of the
+ string to be read.
+ @param[in, out] result A reference to the string variable where the read
+ string is to be stored.
+ @tparam NumberType The type of the length @a len
+ @pre len >= 1
+ @return `true` if the string was successfully parsed
+ */
+ template<typename NumberType>
+ bool get_bson_string(const NumberType len, string_t& result)
+ {
+ if (JSON_UNLIKELY(len < 1))
+ {
+ 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::bson, "string length must be at least 1, is " + std::to_string(len), "string")));
+ }
+
+ return get_string(input_format_t::bson, len - static_cast<NumberType>(1), result) and get() != std::char_traits<char>::eof();
+ }
+
+ /*!
+ @brief Read a BSON document element of the given @a element_type.
+ @param[in] element_type The BSON element type, c.f. http://bsonspec.org/spec.html
+ @param[in] element_type_parse_position The position in the input stream,
+ where the `element_type` was read.
+ @warning Not all BSON element types are supported yet. An unsupported
+ @a element_type will give rise to a parse_error.114:
+ Unsupported BSON record type 0x...
+ @return whether a valid BSON-object/array was passed to the SAX parser
+ */
+ bool parse_bson_element_internal(const int element_type,
+ const std::size_t element_type_parse_position)
+ {
+ switch (element_type)
+ {
+ case 0x01: // double
+ {
+ double number;
+ return get_number<double, true>(input_format_t::bson, number) and sax->number_float(static_cast<number_float_t>(number), "");
+ }
+
+ case 0x02: // string
+ {
+ std::int32_t len;
+ string_t value;
+ return get_number<std::int32_t, true>(input_format_t::bson, len) and get_bson_string(len, value) and sax->string(value);
+ }
+
+ case 0x03: // object
+ {
+ return parse_bson_internal();
+ }
+
+ case 0x04: // array
+ {
+ return parse_bson_array();
+ }
+
+ case 0x08: // boolean
+ {
+ return sax->boolean(get() != 0);
+ }
+
+ case 0x0A: // null
+ {
+ return sax->null();
+ }
+
+ case 0x10: // int32
+ {
+ std::int32_t value;
+ return get_number<std::int32_t, true>(input_format_t::bson, value) and sax->number_integer(value);
+ }
+
+ case 0x12: // int64
+ {
+ std::int64_t value;
+ return get_number<std::int64_t, true>(input_format_t::bson, value) and sax->number_integer(value);
+ }
+
+ default: // anything else not supported (yet)
+ {
+ char cr[3];
+ (std::snprintf)(cr, sizeof(cr), "%.2hhX", static_cast<unsigned char>(element_type));
+ return sax->parse_error(element_type_parse_position, std::string(cr), parse_error::create(114, element_type_parse_position, "Unsupported BSON record type 0x" + std::string(cr)));
+ }
+ }
+ }
+
+ /*!
+ @brief Read a BSON element list (as specified in the BSON-spec)
+
+ The same binary layout is used for objects and arrays, hence it must be
+ indicated with the argument @a is_array which one is expected
+ (true --> array, false --> object).
+
+ @param[in] is_array Determines if the element list being read is to be
+ treated as an object (@a is_array == false), or as an
+ array (@a is_array == true).
+ @return whether a valid BSON-object/array was passed to the SAX parser
+ */
+ bool parse_bson_element_list(const bool is_array)
+ {
+ string_t key;
+ while (int element_type = get())
+ {
+ if (JSON_UNLIKELY(not unexpect_eof(input_format_t::bson, "element list")))
+ {
+ return false;
+ }
+
+ const std::size_t element_type_parse_position = chars_read;
+ if (JSON_UNLIKELY(not get_bson_cstr(key)))
+ {
+ return false;
+ }
+
+ if (not is_array)
+ {
+ if (not sax->key(key))
+ {
+ return false;
+ }
+ }
+
+ if (JSON_UNLIKELY(not parse_bson_element_internal(element_type, element_type_parse_position)))
+ {
+ return false;
+ }
+
+ // get_bson_cstr only appends
+ key.clear();
+ }
+
+ return true;
+ }
+
+ /*!
+ @brief Reads an array from the BSON input and passes it to the SAX-parser.
+ @return whether a valid BSON-array was passed to the SAX parser
+ */
+ bool parse_bson_array()
+ {
+ std::int32_t document_size;
+ get_number<std::int32_t, true>(input_format_t::bson, document_size);
+
+ if (JSON_UNLIKELY(not sax->start_array(std::size_t(-1))))
+ {
+ return false;
+ }
+
+ if (JSON_UNLIKELY(not parse_bson_element_list(/*is_array*/true)))
+ {
+ return false;
+ }
+
+ return sax->end_array();
+ }
+
+ //////////
+ // CBOR //
+ //////////
+
+ /*!
+ @param[in] get_char whether a new character should be retrieved from the
+ input (true, default) or whether the last read
+ character should be considered instead
+
+ @return whether a valid CBOR value was passed to the SAX parser
+ */
+ bool parse_cbor_internal(const bool get_char = true)
+ {
+ switch (get_char ? get() : current)
+ {
+ // EOF
+ case std::char_traits<char>::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)
+ {
+ uint8_t number;
+ return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
+ }
+
+ case 0x19: // Unsigned integer (two-byte uint16_t follows)
+ {
+ uint16_t number;
+ return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
+ }
+
+ case 0x1A: // Unsigned integer (four-byte uint32_t follows)
+ {
+ uint32_t number;
+ return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
+ }
+
+ case 0x1B: // Unsigned integer (eight-byte uint64_t follows)
+ {
+ uint64_t number;
+ return get_number(input_format_t::cbor, number) and 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<int8_t>(0x20 - 1 - current));
+
+ case 0x38: // Negative integer (one-byte uint8_t follows)
+ {
+ uint8_t number;
+ return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1) - number);
+ }
+
+ case 0x39: // Negative integer -1-n (two-byte uint16_t follows)
+ {
+ uint16_t number;
+ return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1) - number);
+ }
+
+ case 0x3A: // Negative integer -1-n (four-byte uint32_t follows)
+ {
+ uint32_t number;
+ return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1) - number);
+ }
+
+ case 0x3B: // Negative integer -1-n (eight-byte uint64_t follows)
+ {
+ uint64_t number;
+ return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1)
+ - static_cast<number_integer_t>(number));
+ }
+
+ // 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) and 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>(current & 0x1F));
+
+ case 0x98: // array (one-byte uint8_t for n follows)
+ {
+ uint8_t len;
+ return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
+ }
+
+ case 0x99: // array (two-byte uint16_t for n follow)
+ {
+ uint16_t len;
+ return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
+ }
+
+ case 0x9A: // array (four-byte uint32_t for n follow)
+ {
+ uint32_t len;
+ return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
+ }
+
+ case 0x9B: // array (eight-byte uint64_t for n follow)
+ {
+ uint64_t len;
+ return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
+ }
+
+ case 0x9F: // array (indefinite length)
+ return get_cbor_array(std::size_t(-1));
+
+ // 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>(current & 0x1F));
+
+ case 0xB8: // map (one-byte uint8_t for n follows)
+ {
+ uint8_t len;
+ return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
+ }
+
+ case 0xB9: // map (two-byte uint16_t for n follow)
+ {
+ uint16_t len;
+ return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
+ }
+
+ case 0xBA: // map (four-byte uint32_t for n follow)
+ {
+ uint32_t len;
+ return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
+ }
+
+ case 0xBB: // map (eight-byte uint64_t for n follow)
+ {
+ uint64_t len;
+ return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
+ }
+
+ case 0xBF: // map (indefinite length)
+ return get_cbor_object(std::size_t(-1));
+
+ 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 int byte1_raw = get();
+ if (JSON_UNLIKELY(not unexpect_eof(input_format_t::cbor, "number")))
+ {
+ return false;
+ }
+ const int byte2_raw = get();
+ if (JSON_UNLIKELY(not 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 int half = (byte1 << 8) + byte2;
+ const double val = [&half]
+ {
+ const int exp = (half >> 10) & 0x1F;
+ const int mant = half & 0x3FF;
+ assert(0 <= exp and exp <= 32);
+ assert(0 <= mant and 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 & 0x8000) != 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) and 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) and 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")));
+ }
+ }
+ }
+
+ /*!
+ @brief reads a CBOR string
+
+ This function first reads starting bytes to determine the expected
+ string length and then copies this number of bytes into a string.
+ Additionally, CBOR's strings with indefinite lengths are supported.
+
+ @param[out] result created string
+
+ @return whether string creation completed
+ */
+ bool get_cbor_string(string_t& result)
+ {
+ if (JSON_UNLIKELY(not unexpect_eof(input_format_t::cbor, "string")))
+ {
+ return false;
+ }
+
+ switch (current)
+ {
+ // 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:
+ {
+ return get_string(input_format_t::cbor, current & 0x1F, result);
+ }
+
+ case 0x78: // UTF-8 string (one-byte uint8_t for n follows)
+ {
+ uint8_t len;
+ return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
+ }
+
+ case 0x79: // UTF-8 string (two-byte uint16_t for n follow)
+ {
+ uint16_t len;
+ return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
+ }
+
+ case 0x7A: // UTF-8 string (four-byte uint32_t for n follow)
+ {
+ uint32_t len;
+ return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
+ }
+
+ case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow)
+ {
+ uint64_t len;
+ return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
+ }
+
+ case 0x7F: // UTF-8 string (indefinite length)
+ {
+ while (get() != 0xFF)
+ {
+ string_t chunk;
+ if (not get_cbor_string(chunk))
+ {
+ return false;
+ }
+ result.append(chunk);
+ }
+ return true;
+ }
+
+ default:
+ {
+ auto last_token = get_token_string();
+ return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::cbor, "expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x" + last_token, "string")));
+ }
+ }
+ }
+
+ /*!
+ @param[in] len the length of the array or std::size_t(-1) for an
+ array of indefinite size
+ @return whether array creation completed
+ */
+ bool get_cbor_array(const std::size_t len)
+ {
+ if (JSON_UNLIKELY(not sax->start_array(len)))
+ {
+ return false;
+ }
+
+ if (len != std::size_t(-1))
+ {
+ for (std::size_t i = 0; i < len; ++i)
+ {
+ if (JSON_UNLIKELY(not parse_cbor_internal()))
+ {
+ return false;
+ }
+ }
+ }
+ else
+ {
+ while (get() != 0xFF)
+ {
+ if (JSON_UNLIKELY(not parse_cbor_internal(false)))
+ {
+ return false;
+ }
+ }
+ }
+
+ return sax->end_array();
+ }
+
+ /*!
+ @param[in] len the length of the object or std::size_t(-1) for an
+ object of indefinite size
+ @return whether object creation completed
+ */
+ bool get_cbor_object(const std::size_t len)
+ {
+ if (not JSON_UNLIKELY(sax->start_object(len)))
+ {
+ return false;
+ }
+
+ string_t key;
+ if (len != std::size_t(-1))
+ {
+ for (std::size_t i = 0; i < len; ++i)
+ {
+ get();
+ if (JSON_UNLIKELY(not get_cbor_string(key) or not sax->key(key)))
+ {
+ return false;
+ }
+
+ if (JSON_UNLIKELY(not parse_cbor_internal()))
+ {
+ return false;
+ }
+ key.clear();
+ }
+ }
+ else
+ {
+ while (get() != 0xFF)
+ {
+ if (JSON_UNLIKELY(not get_cbor_string(key) or not sax->key(key)))
+ {
+ return false;
+ }
+
+ if (JSON_UNLIKELY(not parse_cbor_internal()))
+ {
+ return false;
+ }
+ key.clear();
+ }
+ }
+
+ return sax->end_object();
+ }
+
+ /////////////
+ // MsgPack //
+ /////////////
+
+ /*!
+ @return whether a valid MessagePack value was passed to the SAX parser
+ */
+ bool parse_msgpack_internal()
+ {
+ switch (get())
+ {
+ // EOF
+ case std::char_traits<char>::eof():
+ return unexpect_eof(input_format_t::msgpack, "value");
+
+ // positive fixint
+ 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:
+ case 0x18:
+ case 0x19:
+ case 0x1A:
+ case 0x1B:
+ case 0x1C:
+ case 0x1D:
+ case 0x1E:
+ case 0x1F:
+ 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:
+ case 0x38:
+ case 0x39:
+ case 0x3A:
+ case 0x3B:
+ case 0x3C:
+ case 0x3D:
+ case 0x3E:
+ case 0x3F:
+ 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:
+ case 0x59:
+ case 0x5A:
+ case 0x5B:
+ case 0x5C:
+ case 0x5D:
+ case 0x5E:
+ case 0x5F:
+ 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:
+ case 0x79:
+ case 0x7A:
+ case 0x7B:
+ case 0x7C:
+ case 0x7D:
+ case 0x7E:
+ case 0x7F:
+ return sax->number_unsigned(static_cast<number_unsigned_t>(current));
+
+ // fixmap
+ 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:
+ return get_msgpack_object(static_cast<std::size_t>(current & 0x0F));
+
+ // fixarray
+ case 0x90:
+ case 0x91:
+ case 0x92:
+ case 0x93:
+ case 0x94:
+ case 0x95:
+ case 0x96:
+ case 0x97:
+ case 0x98:
+ case 0x99:
+ case 0x9A:
+ case 0x9B:
+ case 0x9C:
+ case 0x9D:
+ case 0x9E:
+ case 0x9F:
+ return get_msgpack_array(static_cast<std::size_t>(current & 0x0F));
+
+ // fixstr
+ 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:
+ case 0xB8:
+ case 0xB9:
+ case 0xBA:
+ case 0xBB:
+ case 0xBC:
+ case 0xBD:
+ case 0xBE:
+ case 0xBF:
+ {
+ string_t s;
+ return get_msgpack_string(s) and sax->string(s);
+ }
+
+ case 0xC0: // nil
+ return sax->null();
+
+ case 0xC2: // false
+ return sax->boolean(false);
+
+ case 0xC3: // true
+ return sax->boolean(true);
+
+ case 0xCA: // float 32
+ {
+ float number;
+ return get_number(input_format_t::msgpack, number) and sax->number_float(static_cast<number_float_t>(number), "");
+ }
+
+ case 0xCB: // float 64
+ {
+ double number;
+ return get_number(input_format_t::msgpack, number) and sax->number_float(static_cast<number_float_t>(number), "");
+ }
+
+ case 0xCC: // uint 8
+ {
+ uint8_t number;
+ return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
+ }
+
+ case 0xCD: // uint 16
+ {
+ uint16_t number;
+ return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
+ }
+
+ case 0xCE: // uint 32
+ {
+ uint32_t number;
+ return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
+ }
+
+ case 0xCF: // uint 64
+ {
+ uint64_t number;
+ return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
+ }
+
+ case 0xD0: // int 8
+ {
+ int8_t number;
+ return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
+ }
+
+ case 0xD1: // int 16
+ {
+ int16_t number;
+ return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
+ }
+
+ case 0xD2: // int 32
+ {
+ int32_t number;
+ return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
+ }
+
+ case 0xD3: // int 64
+ {
+ int64_t number;
+ return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
+ }
+
+ case 0xD9: // str 8
+ case 0xDA: // str 16
+ case 0xDB: // str 32
+ {
+ string_t s;
+ return get_msgpack_string(s) and sax->string(s);
+ }
+
+ case 0xDC: // array 16
+ {
+ uint16_t len;
+ return get_number(input_format_t::msgpack, len) and get_msgpack_array(static_cast<std::size_t>(len));
+ }
+
+ case 0xDD: // array 32
+ {
+ uint32_t len;
+ return get_number(input_format_t::msgpack, len) and get_msgpack_array(static_cast<std::size_t>(len));
+ }
+
+ case 0xDE: // map 16
+ {
+ uint16_t len;
+ return get_number(input_format_t::msgpack, len) and get_msgpack_object(static_cast<std::size_t>(len));
+ }
+
+ case 0xDF: // map 32
+ {
+ uint32_t len;
+ return get_number(input_format_t::msgpack, len) and get_msgpack_object(static_cast<std::size_t>(len));
+ }
+
+ // negative fixint
+ case 0xE0:
+ case 0xE1:
+ case 0xE2:
+ case 0xE3:
+ case 0xE4:
+ case 0xE5:
+ case 0xE6:
+ case 0xE7:
+ case 0xE8:
+ case 0xE9:
+ case 0xEA:
+ case 0xEB:
+ case 0xEC:
+ case 0xED:
+ case 0xEE:
+ case 0xEF:
+ case 0xF0:
+ case 0xF1:
+ case 0xF2:
+ case 0xF3:
+ case 0xF4:
+ case 0xF5:
+ case 0xF6:
+ case 0xF7:
+ case 0xF8:
+ case 0xF9:
+ case 0xFA:
+ case 0xFB:
+ case 0xFC:
+ case 0xFD:
+ case 0xFE:
+ case 0xFF:
+ return sax->number_integer(static_cast<int8_t>(current));
+
+ default: // anything else
+ {
+ 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::msgpack, "invalid byte: 0x" + last_token, "value")));
+ }
+ }
+ }
+
+ /*!
+ @brief reads a MessagePack string
+
+ This function first reads starting bytes to determine the expected
+ string length and then copies this number of bytes into a string.
+
+ @param[out] result created string
+
+ @return whether string creation completed
+ */
+ bool get_msgpack_string(string_t& result)
+ {
+ if (JSON_UNLIKELY(not unexpect_eof(input_format_t::msgpack, "string")))
+ {
+ return false;
+ }
+
+ switch (current)
+ {
+ // fixstr
+ 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:
+ case 0xB8:
+ case 0xB9:
+ case 0xBA:
+ case 0xBB:
+ case 0xBC:
+ case 0xBD:
+ case 0xBE:
+ case 0xBF:
+ {
+ return get_string(input_format_t::msgpack, current & 0x1F, result);
+ }
+
+ case 0xD9: // str 8
+ {
+ uint8_t len;
+ return get_number(input_format_t::msgpack, len) and get_string(input_format_t::msgpack, len, result);
+ }
+
+ case 0xDA: // str 16
+ {
+ uint16_t len;
+ return get_number(input_format_t::msgpack, len) and get_string(input_format_t::msgpack, len, result);
+ }
+
+ case 0xDB: // str 32
+ {
+ uint32_t len;
+ return get_number(input_format_t::msgpack, len) and get_string(input_format_t::msgpack, len, result);
+ }
+
+ default:
+ {
+ auto last_token = get_token_string();
+ return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::msgpack, "expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0x" + last_token, "string")));
+ }
+ }
+ }
+
+ /*!
+ @param[in] len the length of the array
+ @return whether array creation completed
+ */
+ bool get_msgpack_array(const std::size_t len)
+ {
+ if (JSON_UNLIKELY(not sax->start_array(len)))
+ {
+ return false;
+ }
+
+ for (std::size_t i = 0; i < len; ++i)
+ {
+ if (JSON_UNLIKELY(not parse_msgpack_internal()))
+ {
+ return false;
+ }
+ }
+
+ return sax->end_array();
+ }
+
+ /*!
+ @param[in] len the length of the object
+ @return whether object creation completed
+ */
+ bool get_msgpack_object(const std::size_t len)
+ {
+ if (JSON_UNLIKELY(not sax->start_object(len)))
+ {
+ return false;
+ }
+
+ string_t key;
+ for (std::size_t i = 0; i < len; ++i)
+ {
+ get();
+ if (JSON_UNLIKELY(not get_msgpack_string(key) or not sax->key(key)))
+ {
+ return false;
+ }
+
+ if (JSON_UNLIKELY(not parse_msgpack_internal()))
+ {
+ return false;
+ }
+ key.clear();
+ }
+
+ return sax->end_object();
+ }
+
+ ////////////
+ // UBJSON //
+ ////////////
+
+ /*!
+ @param[in] get_char whether a new character should be retrieved from the
+ input (true, default) or whether the last read
+ character should be considered instead
+
+ @return whether a valid UBJSON value was passed to the SAX parser
+ */
+ bool parse_ubjson_internal(const bool get_char = true)
+ {
+ return get_ubjson_value(get_char ? get_ignore_noop() : current);
+ }
+
+ /*!
+ @brief reads a UBJSON string
+
+ This function is either called after reading the 'S' byte explicitly
+ indicating a string, or in case of an object key where the 'S' byte can be
+ left out.
+
+ @param[out] result created string
+ @param[in] get_char whether a new character should be retrieved from the
+ input (true, default) or whether the last read
+ character should be considered instead
+
+ @return whether string creation completed
+ */
+ bool get_ubjson_string(string_t& result, const bool get_char = true)
+ {
+ if (get_char)
+ {
+ get(); // TODO: may we ignore N here?
+ }
+
+ if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "value")))
+ {
+ return false;
+ }
+
+ switch (current)
+ {
+ case 'U':
+ {
+ uint8_t len;
+ return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+ }
+
+ case 'i':
+ {
+ int8_t len;
+ return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+ }
+
+ case 'I':
+ {
+ int16_t len;
+ return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+ }
+
+ case 'l':
+ {
+ int32_t len;
+ return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+ }
+
+ case 'L':
+ {
+ int64_t len;
+ return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+ }
+
+ default:
+ auto last_token = get_token_string();
+ return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "expected length type specification (U, i, I, l, L); last byte: 0x" + last_token, "string")));
+ }
+ }
+
+ /*!
+ @param[out] result determined size
+ @return whether size determination completed
+ */
+ bool get_ubjson_size_value(std::size_t& result)
+ {
+ switch (get_ignore_noop())
+ {
+ case 'U':
+ {
+ uint8_t number;
+ if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+ {
+ return false;
+ }
+ result = static_cast<std::size_t>(number);
+ return true;
+ }
+
+ case 'i':
+ {
+ int8_t number;
+ if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+ {
+ return false;
+ }
+ result = static_cast<std::size_t>(number);
+ return true;
+ }
+
+ case 'I':
+ {
+ int16_t number;
+ if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+ {
+ return false;
+ }
+ result = static_cast<std::size_t>(number);
+ return true;
+ }
+
+ case 'l':
+ {
+ int32_t number;
+ if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+ {
+ return false;
+ }
+ result = static_cast<std::size_t>(number);
+ return true;
+ }
+
+ case 'L':
+ {
+ int64_t number;
+ if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+ {
+ return false;
+ }
+ result = static_cast<std::size_t>(number);
+ return true;
+ }
+
+ default:
+ {
+ auto last_token = get_token_string();
+ return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "expected length type specification (U, i, I, l, L) after '#'; last byte: 0x" + last_token, "size")));
+ }
+ }
+ }
+
+ /*!
+ @brief determine the type and size for a container
+
+ In the optimized UBJSON format, a type and a size can be provided to allow
+ for a more compact representation.
+
+ @param[out] result pair of the size and the type
+
+ @return whether pair creation completed
+ */
+ bool get_ubjson_size_type(std::pair<std::size_t, int>& result)
+ {
+ result.first = string_t::npos; // size
+ result.second = 0; // type
+
+ get_ignore_noop();
+
+ if (current == '$')
+ {
+ result.second = get(); // must not ignore 'N', because 'N' maybe the type
+ if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "type")))
+ {
+ return false;
+ }
+
+ get_ignore_noop();
+ if (JSON_UNLIKELY(current != '#'))
+ {
+ if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "value")))
+ {
+ return false;
+ }
+ 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::ubjson, "expected '#' after type information; last byte: 0x" + last_token, "size")));
+ }
+
+ return get_ubjson_size_value(result.first);
+ }
+ else if (current == '#')
+ {
+ return get_ubjson_size_value(result.first);
+ }
+ return true;
+ }
+
+ /*!
+ @param prefix the previously read or set type prefix
+ @return whether value creation completed
+ */
+ bool get_ubjson_value(const int prefix)
+ {
+ switch (prefix)
+ {
+ case std::char_traits<char>::eof(): // EOF
+ return unexpect_eof(input_format_t::ubjson, "value");
+
+ case 'T': // true
+ return sax->boolean(true);
+ case 'F': // false
+ return sax->boolean(false);
+
+ case 'Z': // null
+ return sax->null();
+
+ case 'U':
+ {
+ uint8_t number;
+ return get_number(input_format_t::ubjson, number) and sax->number_unsigned(number);
+ }
+
+ case 'i':
+ {
+ int8_t number;
+ return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
+ }
+
+ case 'I':
+ {
+ int16_t number;
+ return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
+ }
+
+ case 'l':
+ {
+ int32_t number;
+ return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
+ }
+
+ case 'L':
+ {
+ int64_t number;
+ return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
+ }
+
+ case 'd':
+ {
+ float number;
+ return get_number(input_format_t::ubjson, number) and sax->number_float(static_cast<number_float_t>(number), "");
+ }
+
+ case 'D':
+ {
+ double number;
+ return get_number(input_format_t::ubjson, number) and sax->number_float(static_cast<number_float_t>(number), "");
+ }
+
+ case 'C': // char
+ {
+ get();
+ if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "char")))
+ {
+ return false;
+ }
+ if (JSON_UNLIKELY(current > 127))
+ {
+ auto last_token = get_token_string();
+ return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "byte after 'C' must be in range 0x00..0x7F; last byte: 0x" + last_token, "char")));
+ }
+ string_t s(1, static_cast<char>(current));
+ return sax->string(s);
+ }
+
+ case 'S': // string
+ {
+ string_t s;
+ return get_ubjson_string(s) and sax->string(s);
+ }
+
+ case '[': // array
+ return get_ubjson_array();
+
+ case '{': // object
+ return get_ubjson_object();
+
+ default: // anything else
+ {
+ 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::ubjson, "invalid byte: 0x" + last_token, "value")));
+ }
+ }
+ }
+
+ /*!
+ @return whether array creation completed
+ */
+ bool get_ubjson_array()
+ {
+ std::pair<std::size_t, int> size_and_type;
+ if (JSON_UNLIKELY(not get_ubjson_size_type(size_and_type)))
+ {
+ return false;
+ }
+
+ if (size_and_type.first != string_t::npos)
+ {
+ if (JSON_UNLIKELY(not sax->start_array(size_and_type.first)))
+ {
+ return false;
+ }
+
+ if (size_and_type.second != 0)
+ {
+ if (size_and_type.second != 'N')
+ {
+ for (std::size_t i = 0; i < size_and_type.first; ++i)
+ {
+ if (JSON_UNLIKELY(not get_ubjson_value(size_and_type.second)))
+ {
+ return false;
+ }
+ }
+ }
+ }
+ else
+ {
+ for (std::size_t i = 0; i < size_and_type.first; ++i)
+ {
+ if (JSON_UNLIKELY(not parse_ubjson_internal()))
+ {
+ return false;
+ }
+ }
+ }
+ }
+ else
+ {
+ if (JSON_UNLIKELY(not sax->start_array(std::size_t(-1))))
+ {
+ return false;
+ }
+
+ while (current != ']')
+ {
+ if (JSON_UNLIKELY(not parse_ubjson_internal(false)))
+ {
+ return false;
+ }
+ get_ignore_noop();
+ }
+ }
+
+ return sax->end_array();
+ }
+
+ /*!
+ @return whether object creation completed
+ */
+ bool get_ubjson_object()
+ {
+ std::pair<std::size_t, int> size_and_type;
+ if (JSON_UNLIKELY(not get_ubjson_size_type(size_and_type)))
+ {
+ return false;
+ }
+
+ string_t key;
+ if (size_and_type.first != string_t::npos)
+ {
+ if (JSON_UNLIKELY(not sax->start_object(size_and_type.first)))
+ {
+ return false;
+ }
+
+ if (size_and_type.second != 0)
+ {
+ for (std::size_t i = 0; i < size_and_type.first; ++i)
+ {
+ if (JSON_UNLIKELY(not get_ubjson_string(key) or not sax->key(key)))
+ {
+ return false;
+ }
+ if (JSON_UNLIKELY(not get_ubjson_value(size_and_type.second)))
+ {
+ return false;
+ }
+ key.clear();
+ }
+ }
+ else
+ {
+ for (std::size_t i = 0; i < size_and_type.first; ++i)
+ {
+ if (JSON_UNLIKELY(not get_ubjson_string(key) or not sax->key(key)))
+ {
+ return false;
+ }
+ if (JSON_UNLIKELY(not parse_ubjson_internal()))
+ {
+ return false;
+ }
+ key.clear();
+ }
+ }
+ }
+ else
+ {
+ if (JSON_UNLIKELY(not sax->start_object(std::size_t(-1))))
+ {
+ return false;
+ }
+
+ while (current != '}')
+ {
+ if (JSON_UNLIKELY(not get_ubjson_string(key, false) or not sax->key(key)))
+ {
+ return false;
+ }
+ if (JSON_UNLIKELY(not parse_ubjson_internal()))
+ {
+ return false;
+ }
+ get_ignore_noop();
+ key.clear();
+ }
+ }
+
+ return sax->end_object();
+ }
+
+ ///////////////////////
+ // Utility functions //
+ ///////////////////////
+
+ /*!
+ @brief get next character from the input
+
+ This function provides the interface to the used input adapter. It does
+ not throw in case the input reached EOF, but returns a -'ve valued
+ `std::char_traits<char>::eof()` in that case.
+
+ @return character read from the input
+ */
+ int get()
+ {
+ ++chars_read;
+ return (current = ia->get_character());
+ }
+
+ /*!
+ @return character read from the input after ignoring all 'N' entries
+ */
+ int get_ignore_noop()
+ {
+ do
+ {
+ get();
+ }
+ while (current == 'N');
+
+ return current;
+ }
+
+ /*
+ @brief read a number from the input
+
+ @tparam NumberType the type of the number
+ @param[in] format the current format (for diagnostics)
+ @param[out] result number of type @a NumberType
+
+ @return whether conversion completed
+
+ @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 InputIsLittleEndian = false>
+ bool get_number(const input_format_t format, NumberType& result)
+ {
+ // step 1: read input into array with system's byte order
+ std::array<uint8_t, sizeof(NumberType)> vec;
+ for (std::size_t i = 0; i < sizeof(NumberType); ++i)
+ {
+ get();
+ if (JSON_UNLIKELY(not unexpect_eof(format, "number")))
+ {
+ return false;
+ }
+
+ // reverse byte order prior to conversion if necessary
+ if (is_little_endian && !InputIsLittleEndian)
+ {
+ vec[sizeof(NumberType) - i - 1] = static_cast<uint8_t>(current);
+ }
+ else
+ {
+ vec[i] = static_cast<uint8_t>(current); // LCOV_EXCL_LINE
+ }
+ }
+
+ // step 2: convert array into number of type T and return
+ std::memcpy(&result, vec.data(), sizeof(NumberType));
+ return true;
+ }
+
+ /*!
+ @brief create a string by reading characters from the input
+
+ @tparam NumberType the type of the number
+ @param[in] format the current format (for diagnostics)
+ @param[in] len number of characters to read
+ @param[out] result string created by reading @a len bytes
+
+ @return whether string creation completed
+
+ @note We can not reserve @a len bytes for the result, because @a len
+ may be too large. Usually, @ref unexpect_eof() detects the end of
+ the input before we run out of string memory.
+ */
+ template<typename NumberType>
+ bool get_string(const input_format_t format,
+ const NumberType len,
+ string_t& result)
+ {
+ bool success = true;
+ std::generate_n(std::back_inserter(result), len, [this, &success, &format]()
+ {
+ get();
+ if (JSON_UNLIKELY(not unexpect_eof(format, "string")))
+ {
+ success = false;
+ }
+ return static_cast<char>(current);
+ });
+ return success;
+ }
+
+ /*!
+ @param[in] format the current format (for diagnostics)
+ @param[in] context further context information (for diagnostics)
+ @return whether the last read character is not EOF
+ */
+ bool unexpect_eof(const input_format_t format, const char* context) const
+ {
+ if (JSON_UNLIKELY(current == std::char_traits<char>::eof()))
+ {
+ return sax->parse_error(chars_read, "<end of file>",
+ parse_error::create(110, chars_read, exception_message(format, "unexpected end of input", context)));
+ }
+ return true;
+ }
+
+ /*!
+ @return a string representation of the last read byte
+ */
+ std::string get_token_string() const
+ {
+ char cr[3];
+ (std::snprintf)(cr, 3, "%.2hhX", static_cast<unsigned char>(current));
+ return std::string{cr};
+ }
+
+ /*!
+ @param[in] format the current format
+ @param[in] detail a detailed error message
+ @param[in] context further contect information
+ @return a message string to use in the parse_error exceptions
+ */
+ std::string exception_message(const input_format_t format,
+ const std::string& detail,
+ const std::string& context) const
+ {
+ std::string error_msg = "syntax error while parsing ";
+
+ switch (format)
+ {
+ case input_format_t::cbor:
+ error_msg += "CBOR";
+ break;
+
+ case input_format_t::msgpack:
+ error_msg += "MessagePack";
+ break;
+
+ case input_format_t::ubjson:
+ error_msg += "UBJSON";
+ break;
+
+ case input_format_t::bson:
+ error_msg += "BSON";
+ break;
+
+ // LCOV_EXCL_START
+ default:
+ assert(false);
+ // LCOV_EXCL_STOP
+ }
+
+ return error_msg + " " + context + ": " + detail;
+ }
+
+ private:
+ /// input adapter
+ input_adapter_t ia = nullptr;
+
+ /// the current character
+ int current = std::char_traits<char>::eof();
+
+ /// the number of characters read
+ std::size_t chars_read = 0;
+
+ /// whether we can assume little endianess
+ const bool is_little_endian = little_endianess();
+
+ /// the SAX parser
+ json_sax_t* sax = nullptr;
+};
+} // namespace detail
+} // namespace nlohmann