Javascript implementation of xxHash

Synopsis

xxHash is a very fast hashing algorithm (see the details here). xxhashjs is a Javascript implementation of it, written in 100% Javascript. Although not as fast as the C version, it does perform pretty well given the current Javascript limitations in handling unsigned 32 bits integers.

Installation

In nodejs:

npm install xxhashjs

In the browser, include the following, and access the constructor with XXH:

<script src="/your/path/to/xxhash.lmd.js"></script>

Examples

• In one step:

var h = XXH( 'abcd', 0xABCD ).toString(16)	// seed = 0xABCD

0xCDA8FAE4

• In several steps (useful in conjunction of NodeJS streams):

var H = XXH( 0xABCD )	// seed = 0xABCD
var h = H.update( 'abcd' ).digest().toString(16)

0xCDA8FAE4

• More examples in the examples directory:
  • Compute xxHash from a file data
  • Use xxHashjs in the browser

Usage

• In one step: XXH(<data>, <seed>) The data can either be a string or a NodeJS Buffer object. The seed can either be a number or a UINT32 object.

• In several steps:

  • instantiate a new XXH object: XXH(<seed>) or XXH() The seed can be set later on with the init method

  • add data to the hash calculation:

XXH.update(<data>)

* finish the calculations:

XXH.digest()

The object returned can be converted to a string with toString(<radix>) or a number toNumber(). Once digest() has been called, the object can be reused. The same seed will be used or it can be changed with init(<seed>).

Methods

• XXH.init(<seed>) Initialize the XXH object with the given seed. The seed can either be a number or a UINT32 object.
• XXH.update(<data>) Add data for hashing. The data can either be a string or a NodeJS Buffer object.
• XXH.digest() (UINT32) Finalize the hash calculations and returns an UINT32 object. The hash value can be retrived with toString().

License

MIT