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-rw-r--r--core/deflator.js79
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+/*
+ * 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) {
+ 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;
+
+ 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 {
+ this.strm.output = new Uint8Array(this.chunkSize);
+ this.strm.next_out = 0;
+ this.strm.avail_out = this.chunkSize;
+
+ 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;
+ }
+
+ this.strm.input = null;
+ this.strm.avail_in = 0;
+ this.strm.next_in = 0;
+
+ return outData;
+ }
+
+}