memcpy

node-memcpy
===========
Copies data between node Buffers and/or ArrayBuffers up to ~75 times faster than in pure JS.

Wait, what?
-----------
node.js utilizes a non-standard concept of I/O buffers and thus has both its Buffer as well as ArrayBuffer support.
While Buffers are nice because they are a lot faster than V8's ArrayBuffers, transferring data between those two
types can be ridiculously slow. This is where a node module like memcpy comes into play.

``
// C++ binding

i memcpy.100k > cc Buffer -> Buffer: 22.756ms
i memcpy.100k > cc Buffer -> ArrayBuffer: 23.861ms

i memcpy.100k > cc ArrayBuffer -> Buffer: 22.955ms
i memcpy.100k > cc ArrayBuffer -> ArrayBuffer: 23.273ms

// Native JS

i memcpy.100k > js Buffer -> Buffer: 21.617ms
i memcpy.100k > js Buffer -> ArrayBuffer: 993.361ms

i memcpy.100k > js ArrayBuffer -> Buffer: 940.273ms
i memcpy.100k > js ArrayBuffer -> ArrayBuffer: 1626.182ms
`

API
---
##### memcpy(target[, targetStart=0], source[, sourceStart=0[, sourceEnd=source.length]):bytesCopied

| Argument | Type | Optional | Description
|--------------|---------------------------|-----------|------------------------------------------------------------------
| target | Buffer | ArrayBuffer | | Target buffer to copy to
| targetStart | number | omittable | Target offset to begin copying to, defaults to 0
| source | Buffer | ArrayBuffer | | Source buffer to copy from
| sourceStart | number | optional | Source offset to begin copying from, defaults to 0
| sourceEnd | number | optional | Source offset to end copying from, defaults ot source.length
| @returns | number | | Number of bytes copied

Source and target regions may overlap.

Usage
-----
* npm install memcpy

`js
var memcpy = require("memcpy"), // C++ binding if available, else native JS
memcpy_binding = memcpy.binding, // C++ binding or NULL if not available
memcpy_native = memcpy.native; // Native JS
...
``

Please keep in mind that - besides the nice numbers - this is still to be considered experimental. I'd love if you'd
review the C++ code to validate that it's safe. I can't yet think of a sane use case, though, as just sticking with
Buffers on node.js and ArrayBuffers in the browser should be best practice.

Contributors
------------
Denys Khanzhiyev (node 0.11.13+ support with nan)

License: Apache License, Version 2.0