You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
117 lines
3.1 KiB
117 lines
3.1 KiB
5 years ago
|
# crc
|
||
|
|
|
||
|
|
The module for calculating Cyclic Redundancy Check (CRC) for Node.js and the Browser.
|
||
|
|
|
||
|
|
## Features
|
||
|
|
|
||
|
|
- Full test suite comparing values against reference `pycrc` implementation.
|
||
|
|
- Pure JavaScript implementation, no dependencies.
|
||
|
|
- ES6 modules.
|
||
|
|
- Provides CRC tables for optimized calculations.
|
||
|
|
- Provides support for the following CRC algorithms:
|
||
|
|
- CRC1 (`crc1`)
|
||
|
|
- CRC8 (`crc8`)
|
||
|
|
- CRC8 1-Wire (`crc81wire`)
|
||
|
|
- CRC16 (`crc16`)
|
||
|
|
- CRC16 CCITT (`crc16ccitt`)
|
||
|
|
- CRC16 Modbus (`crc16modbus`)
|
||
|
|
- CRC16 Kermit (`crc16kermit`)
|
||
|
|
- CRC16 XModem (`crc16xmodem`)
|
||
|
|
- CRC24 (`crc24`)
|
||
|
|
- CRC32 (`crc32`)
|
||
|
|
- CRCJAM (`crcjam`)
|
||
|
|
|
||
|
|
## Installation
|
||
|
|
|
||
|
|
```
|
||
|
|
npm install crc
|
||
|
|
```
|
||
|
|
|
||
|
|
## Usage
|
||
|
|
|
||
|
|
Calculate a CRC32 (recommended way):
|
||
|
|
|
||
|
|
```js
|
||
|
|
import crc32 from 'crc/crc32';
|
||
|
|
crc32('hello').toString(16);
|
||
|
|
// "3610a686"
|
||
|
|
```
|
||
|
|
|
||
|
|
Import everything (this may bloat bundle size):
|
||
|
|
|
||
|
|
```js
|
||
|
|
import crc from 'crc';
|
||
|
|
crc.crc32('hello').toString(16);
|
||
|
|
// "3610a686"
|
||
|
|
```
|
||
|
|
|
||
|
|
Or use CommonJS (compatability mode, no longer recommended):
|
||
|
|
|
||
|
|
```js
|
||
|
|
const { crc32 } = require('crc');
|
||
|
|
crc32('hello').toString(16);
|
||
|
|
// "3610a686"
|
||
|
|
```
|
||
|
|
|
||
|
|
Calculate a CRC32 of a file:
|
||
|
|
|
||
|
|
```js
|
||
|
|
crc32(fs.readFileSync('README.md', 'utf8')).toString(16);
|
||
|
|
// "127ad531"
|
||
|
|
```
|
||
|
|
|
||
|
|
Or using a `Buffer`:
|
||
|
|
|
||
|
|
```js
|
||
|
|
crc32(fs.readFileSync('README.md', 'utf8')).toString(16);
|
||
|
|
// "127ad531"
|
||
|
|
```
|
||
|
|
|
||
|
|
Incrementally calculate a CRC32:
|
||
|
|
|
||
|
|
```js
|
||
|
|
value = crc.crc32('one');
|
||
|
|
value = crc.crc32('two', value);
|
||
|
|
value = crc.crc32('three', value);
|
||
|
|
value.toString(16);
|
||
|
|
// "9e1c092"
|
||
|
|
```
|
||
|
|
|
||
|
|
# Important: Node >= 6.3.0 < 6.9.2
|
||
|
|
|
||
|
|
There's was a bug in Node [#9342](https://github.com/nodejs/node/issues/9342) that affected CRC calculation if `Buffer.split()` is used (see issue discussion for details). This affected all version starting from `6.3.0` up to but not including `6.9.2`. The patch [#9341](https://github.com/nodejs/node/pull/9341) was released in `6.9.2`. If you are upgrading and seeing odd CRC calculation mismatches, this might be the reason.
|
||
|
|
|
||
|
|
## Running tests
|
||
|
|
|
||
|
|
```
|
||
|
|
npm test
|
||
|
|
```
|
||
|
|
|
||
|
|
## Thanks!
|
||
|
|
|
||
|
|
[pycrc](http://www.tty1.net/pycrc/) library is which the source of all of the CRC tables.
|
||
|
|
|
||
|
|
# License
|
||
|
|
|
||
|
|
The MIT License (MIT)
|
||
|
|
|
||
|
|
Copyright (c) 2014 Alex Gorbatchev
|
||
|
|
|
||
|
|
Permission is hereby granted, free of charge, to any person obtaining a copy
|
||
|
|
of this software and associated documentation files (the "Software"), to deal
|
||
|
|
in the Software without restriction, including without limitation the rights
|
||
|
|
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||
|
|
copies of the Software, and to permit persons to whom the Software is
|
||
|
|
furnished to do so, subject to the following conditions:
|
||
|
|
|
||
|
|
The above copyright notice and this permission notice shall be included in
|
||
|
|
all copies or substantial portions of the Software.
|
||
|
|
|
||
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||
|
|
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||
|
|
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||
|
|
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||
|
|
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||
|
|
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||
|
|
THE SOFTWARE.
|