line_push/node_modules/crc/crc1.js
2022-07-21 03:28:35 +00:00

21 lines
444 B
JavaScript

import { Buffer } from 'buffer';
import createBuffer from './create_buffer';
import defineCrc from './define_crc';
const crc1 = defineCrc('crc1', function(buf, previous) {
if (!Buffer.isBuffer(buf)) buf = createBuffer(buf);
let crc = ~~previous;
let accum = 0;
for (let index = 0; index < buf.length; index++) {
const byte = buf[index];
accum += byte;
}
crc += accum % 256;
return crc % 256;
});
export default crc1;