rollsum

Documentation

Overview

Package adler32 implements the Adler-32 checksum.

It is defined in RFC 1950:

Adler-32 is composed of two sums accumulated per byte: s1 is
the sum of all bytes, s2 is the sum of all s1 values. Both sums
are done modulo 65521. s1 is initialized to 1, s2 to zero.  The
Adler-32 checksum is stored as s2*65536 + s1 in most-
significant-byte first (network) order.

Index

• Constants
• func Checksum(data []byte) uint32
• func New(n uint32) hash.Hash32
• type Rollsum
  • func (d *Rollsum) BlockSize() int
  • func (d *Rollsum) Reset()
  • func (d *Rollsum) Size() int
  • func (d *Rollsum) Sum(in []byte) []byte
  • func (d *Rollsum) Sum32() uint32
  • func (d *Rollsum) Write(p []byte) (nn int, err error)

Constants

const Size = 4

The size of an Adler-32 checksum in bytes.

Functions

func Checksum

func Checksum(data []byte) uint32

Checksum returns the Adler-32 checksum of data.

func New

func New(n uint32) hash.Hash32

New returns a new hash.Hash32 computing the Adler-32 checksum.

Types

type Rollsum

type Rollsum struct {
	// contains filtered or unexported fields
}

Rollsum represents the partial evaluation of a checksum. The low 16 bits are s1, the high 16 bits are s2.

func (*Rollsum) BlockSize

func (d *Rollsum) BlockSize() int

func (*Rollsum) Reset

func (d *Rollsum) Reset()

func (*Rollsum) Size

func (d *Rollsum) Size() int

func (*Rollsum) Sum

func (d *Rollsum) Sum(in []byte) []byte

func (*Rollsum) Sum32

func (d *Rollsum) Sum32() uint32

func (*Rollsum) Write

func (d *Rollsum) Write(p []byte) (nn int, err error)