Package crc64


Package crc64 implements the 64-bit cyclic redundancy check, or CRC-64, checksum. See https://en.wikipedia.org/wiki/Cyclic_redundancy_check for information.


Package files



Predefined polynomials.

const (
    // The ISO polynomial, defined in ISO 3309 and used in HDLC.
    ISO = 0xD800000000000000

    // The ECMA polynomial, defined in ECMA 182.
    ECMA = 0xC96C5795D7870F42

The size of a CRC-64 checksum in bytes.

const Size = 8

func ChecksumSource

func Checksum(data []byte, tab *Table) uint64

Checksum returns the CRC-64 checksum of data using the polynomial represented by the Table.

func NewSource

func New(tab *Table) hash.Hash64

New creates a new hash.Hash64 computing the CRC-64 checksum using the polynomial represented by the Table. Its Sum method will lay the value out in big-endian byte order. The returned Hash64 also implements encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to marshal and unmarshal the internal state of the hash.

func UpdateSource

func Update(crc uint64, tab *Table, p []byte) uint64

Update returns the result of adding the bytes in p to the crc.

type TableSource

Table is a 256-word table representing the polynomial for efficient processing.

type Table [256]uint64

func MakeTableSource

func MakeTable(poly uint64) *Table

MakeTable returns a Table constructed from the specified polynomial. The contents of this Table must not be modified.

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Licensed under the Creative Commons Attribution License 3.0.