You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
44 lines
1.4 KiB
JavaScript
44 lines
1.4 KiB
JavaScript
5 months ago
|
"use strict";
|
||
|
|
Object.defineProperty(exports, "__esModule", { value: true });
|
||
|
|
exports.ByteLengthParser = void 0;
|
||
|
|
const stream_1 = require("stream");
|
||
|
|
/**
|
||
|
|
* Emit data every number of bytes
|
||
|
|
*
|
||
|
|
* A transform stream that emits data as a buffer after a specific number of bytes are received. Runs in O(n) time.
|
||
|
|
*/
|
||
|
|
class ByteLengthParser extends stream_1.Transform {
|
||
|
|
constructor(options) {
|
||
|
|
super(options);
|
||
|
|
if (typeof options.length !== 'number') {
|
||
|
|
throw new TypeError('"length" is not a number');
|
||
|
|
}
|
||
|
|
if (options.length < 1) {
|
||
|
|
throw new TypeError('"length" is not greater than 0');
|
||
|
|
}
|
||
|
|
this.length = options.length;
|
||
|
|
this.position = 0;
|
||
|
|
this.buffer = Buffer.alloc(this.length);
|
||
|
|
}
|
||
|
|
_transform(chunk, _encoding, cb) {
|
||
|
|
let cursor = 0;
|
||
|
|
while (cursor < chunk.length) {
|
||
|
|
this.buffer[this.position] = chunk[cursor];
|
||
|
|
cursor++;
|
||
|
|
this.position++;
|
||
|
|
if (this.position === this.length) {
|
||
|
|
this.push(this.buffer);
|
||
|
|
this.buffer = Buffer.alloc(this.length);
|
||
|
|
this.position = 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
cb();
|
||
|
|
}
|
||
|
|
_flush(cb) {
|
||
|
|
this.push(this.buffer.slice(0, this.position));
|
||
|
|
this.buffer = Buffer.alloc(this.length);
|
||
|
|
cb();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
exports.ByteLengthParser = ByteLengthParser;
|