Package Exports
- buffer-crc32
This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (buffer-crc32) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.
Readme
buffer-crc32
crc32 that works with binary data and fancy character sets, outputs buffer, signed or unsigned data and has tests.
Derived from the sample CRC implementation in the PNG specification: http://www.w3.org/TR/PNG/#D-CRCAppendix
install
npm install buffer-crc32example
var crc32 = require('buffer-crc32');
// works with buffers
var buf = Buffer([0x00, 0x73, 0x75, 0x70, 0x20, 0x62, 0x72, 0x6f, 0x00])
crc32(buf) // -> <Buffer 94 5a ab 4a>
// has convenience methods for getting signed or unsigned ints
crc32.signed(buf) // -> -1805997238
crc32.unsigned(buf) // -> 2488970058
// will cast to buffer if given a string, so you can
// directly use foreign characters safely
crc32('自動販売機') // -> <Buffer cb 03 1a c5>
// and works in append mode too
var partialCrc = crc32('hey');
var partialCrc = crc32(' ', partialCrc);
var partialCrc = crc32('sup', partialCrc);
var partialCrc = crc32(' ', partialCrc);
var finalCrc = crc32('bros', partialCrc); // -> <Buffer 47 fa 55 70>tests
This was tested against the output of zlib's crc32 method. You can run
the tests withnpm test (requires tap)
see also
https://github.com/alexgorbatchev/node-crc, crc.buffer.crc32 also
supports buffer inputs and return unsigned ints (thanks @tjholowaychuk).
license
MIT/X11