#hash #rolling #byte #buzhash

fbuzhash

A buzhash rolling hash function

1 unstable release

0.0.1 Apr 21, 2021

#28 in #rolling


Used in fixity

Custom license

13KB
176 lines

fbuzhash

**NOTE: This crate is a port of https://github.com/silvasur/buzhash and will focus on a subset of parity and correctness. The only addition i expect to make are some golden-master tests to ensure parity of ported code. Anything else is out of scope.

Package buzhash implements a buzhash algorithm using this defintion http://en.wikipedia.org/wiki/Rolling_hash#Cyclic_polynomial.

Rolling hash

Buzhash is a rolling hash function, that means that the current hash sum is the sum of the last n consumed bytes.

Example:

  • Message 1: This is a stupid example text to demonstrate buzhash.
  • Message 2: Another text to demonstrate buzhash.

When hashing both messages with a buzhasher with n=16, both messages will have the same hash sum, since the last 16 characters (nstrate buzhash.) are equal.

This can be useful, when searching for a data fragment in large files, without knowing the fragment (only its hash). This is used in binary diff tools, such as rdiff (although they use a different rolling hash function).

Dependencies

~87KB