Hype-2/static/core/deflator.js

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2023-10-17 08:03:51 +00:00
/*
* noVNC: HTML5 VNC client
* Copyright (C) 2020 The noVNC Authors
* Licensed under MPL 2.0 (see LICENSE.txt)
*
* See README.md for usage and integration instructions.
*/
import { deflateInit, deflate } from "../vendor/pako/lib/zlib/deflate.js";
import { Z_FULL_FLUSH } from "../vendor/pako/lib/zlib/deflate.js";
import ZStream from "../vendor/pako/lib/zlib/zstream.js";
export default class Deflator {
constructor() {
this.strm = new ZStream();
this.chunkSize = 1024 * 10 * 10;
this.outputBuffer = new Uint8Array(this.chunkSize);
this.windowBits = 5;
deflateInit(this.strm, this.windowBits);
}
deflate(inData) {
/* eslint-disable camelcase */
this.strm.input = inData;
this.strm.avail_in = this.strm.input.length;
this.strm.next_in = 0;
this.strm.output = this.outputBuffer;
this.strm.avail_out = this.chunkSize;
this.strm.next_out = 0;
/* eslint-enable camelcase */
let lastRet = deflate(this.strm, Z_FULL_FLUSH);
let outData = new Uint8Array(this.strm.output.buffer, 0, this.strm.next_out);
if (lastRet < 0) {
throw new Error("zlib deflate failed");
}
if (this.strm.avail_in > 0) {
// Read chunks until done
let chunks = [outData];
let totalLen = outData.length;
do {
/* eslint-disable camelcase */
this.strm.output = new Uint8Array(this.chunkSize);
this.strm.next_out = 0;
this.strm.avail_out = this.chunkSize;
/* eslint-enable camelcase */
lastRet = deflate(this.strm, Z_FULL_FLUSH);
if (lastRet < 0) {
throw new Error("zlib deflate failed");
}
let chunk = new Uint8Array(this.strm.output.buffer, 0, this.strm.next_out);
totalLen += chunk.length;
chunks.push(chunk);
} while (this.strm.avail_in > 0);
// Combine chunks into a single data
let newData = new Uint8Array(totalLen);
let offset = 0;
for (let i = 0; i < chunks.length; i++) {
newData.set(chunks[i], offset);
offset += chunks[i].length;
}
outData = newData;
}
/* eslint-disable camelcase */
this.strm.input = null;
this.strm.avail_in = 0;
this.strm.next_in = 0;
/* eslint-enable camelcase */
return outData;
}
}