CBORUtilities

CBORUtilities

Solidity library built for decoding CBOR data.

parseField

function parseField(bytes encoding, uint256 cursor) internal view returns (enum CBORSpec.MajorType majorType, uint8 shortCount, uint256 start, uint256 end, uint256 next)

Intelligently parses supported CBOR-encoded types.

Name	Type	Description
encoding	bytes	the dynamic bytes array
cursor	uint256	position where type starts (in bytes)

Name	Type	Description
majorType	enum CBORSpec.MajorType	the type of the data sliced
shortCount	uint8	the corresponding shortCount for the data
start	uint256	position where the data starts (in bytes)
end	uint256	position where the data ends (in bytes)
next	uint256	position to find the next field (in bytes)

extractValue

function extractValue(bytes encoding, enum CBORSpec.MajorType majorType, uint8 shortCount, uint256 start, uint256 end) internal view returns (bytes value)

Extracts the data from CBOR-encoded type.

Name	Type	Description
encoding	bytes	the dynamic bytes array to slice from
majorType	enum CBORSpec.MajorType	the correspondnig data type being used
shortCount	uint8
start	uint256	position where type starts (in bytes)
end	uint256	position where the type ends (in bytes)

Name	Type	Description
value	bytes	a cloned dynamic bytes array with the data value

parseFieldEncoding

function parseFieldEncoding(bytes1 fieldEncoding) internal view returns (enum CBORSpec.MajorType majorType, uint8 shortCount)

Parses a CBOR byte into major type and short count. See https://en.wikipedia.org/wiki/CBOR for reference.

Name	Type	Description
fieldEncoding	bytes1	the field to encode

Name	Type	Description
majorType	enum CBORSpec.MajorType	corresponding data type (see RFC8949 section 3.2)
shortCount	uint8	corresponding short count (see RFC8949 section 3)

scanIndefiniteItems

function scanIndefiniteItems(bytes encoding, uint256 cursor, uint256 maxItems) internal view returns (uint256 totalItems, uint256 endCursor)

If data structures are nested, this will be a recursive function.

Counts encoded items until a BREAK or the end of the bytes.

Name	Type	Description
encoding	bytes	the encoded bytes array
cursor	uint256	where to start scanning
maxItems	uint256	once this number of items is reached, return. Set 0 for infinite

Name	Type	Description
totalItems	uint256	total items found in encoding
endCursor	uint256	cursor position after scanning (non-inclusive)