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_:

``javascript

`

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() 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().

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