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:

Examples

• In one step:

  javascript
  var h = XXH.h32( 'abcd', 0xABCD ).toString(16)  // seed = 0xABCD
  

  0xCDA8FAE4

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

  javascript
  var H = XXH.h32( 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

• XXH makes 2 functions available for 32 bits XXH and 64 bits XXH respectively, with the same signature:

  • XXH.h32
  • XXH.h64

• In one step:

  XXH.h32(, )

  The data can either be a string, an ArrayBuffer or a NodeJS Buffer object. The seed can either be a number or a UINT32 object.

• In several steps:

  • instantiate a new XXH object H:

    XXH.h32()

    or

    XXH.h32()

    The seed can be set later on with the

    init

    method
  • add data to the hash calculation:

    H.update()

  • finish the calculations:

    H.digest()

The object returned can be converted to a string with

toString()

toNumber()

digest()

init()

Methods

• XXH.h32()

  • .init()

    Initialize the XXH object with the given seed. The seed can either be a number or a UINT32 object.

  • .update()

    Add data for hashing. The data can either be a string, an ArrayBuffer or a NodeJS Buffer object.

• digest()

  (UINT32) Finalize the hash calculations and returns an UINT32 object. The hash value can be retrieved with toString().

• XXH.h64()

  • .init()

    Initialize the XXH object with the given seed. The seed can either be a number or a UINT64 object.

  • .update()

    Add data for hashing. The data can either be a string, an ArrayBuffer or a NodeJS Buffer object.

  • .digest()

    (UINT64) Finalize the hash calculations and returns an UINT64 object. The hash value can be retrieved with toString().

License

MIT