playcanvas
Version:
Open-source WebGL/WebGPU 3D engine for the web
132 lines (131 loc) • 4.42 kB
JavaScript
var __defProp = Object.defineProperty;
var __defNormalProp = (obj, key, value) => key in obj ? __defProp(obj, key, { enumerable: true, configurable: true, writable: true, value }) : obj[key] = value;
var __publicField = (obj, key, value) => __defNormalProp(obj, typeof key !== "symbol" ? key + "" : key, value);
import { EventHandler } from "../../core/event-handler.js";
class Untar extends EventHandler {
/**
* Create an instance of an Untar.
*
* @param {Promise} fetchPromise - A Promise object returned from a fetch request.
* @param {string} assetsPrefix - Assets registry files prefix.
*/
constructor(fetchPromise, assetsPrefix = "") {
super();
/** @private */
__publicField(this, "headerSize", 512);
/** @private */
__publicField(this, "paddingSize", 512);
/** @private */
__publicField(this, "bytesRead", 0);
/** @private */
__publicField(this, "bytesReceived", 0);
/** @private */
__publicField(this, "headerRead", false);
/**
* @type {ReadableStream|null}
* @private
*/
__publicField(this, "reader", null);
/**
* @type {Uint8Array}
* @private
*/
__publicField(this, "data", new Uint8Array(0));
/**
* @type {TextDecoder|null}
* @private
*/
__publicField(this, "decoder", null);
/** @private */
__publicField(this, "prefix", "");
/** @private */
__publicField(this, "fileName", "");
/** @private */
__publicField(this, "fileSize", 0);
/** @private */
__publicField(this, "fileType", "");
/** @private */
__publicField(this, "ustarFormat", "");
this.prefix = assetsPrefix || "";
this.reader = fetchPromise.body.getReader();
this.reader.read().then((res) => {
this.pump(res.done, res.value);
}).catch((err) => {
this.fire("error", err);
});
}
/**
* This method is called multiple times when the stream provides data.
*
* @param {boolean} done - True when reading data is complete.
* @param {Uint8Array} value - Chunk of data read from a stream.
* @returns {Promise|null} Return new pump Promise or null when no more data is available.
*/
pump(done, value) {
if (done) {
this.fire("done");
return null;
}
this.bytesReceived += value.byteLength;
const data = new Uint8Array(this.data.length + value.length);
data.set(this.data);
data.set(value, this.data.length);
this.data = data;
while (this.readFile()) ;
return this.reader.read().then((res) => {
this.pump(res.done, res.value);
}).catch((err) => {
this.fire("error", err);
});
}
/**
* Attempt to read file from an available data buffer
*
* @returns {boolean} True if file was successfully read and more data is potentially available for
* processing.
*/
readFile() {
if (!this.headerRead && this.bytesReceived > this.bytesRead + this.headerSize) {
this.headerRead = true;
const view = new DataView(this.data.buffer, this.bytesRead, this.headerSize);
this.decoder ?? (this.decoder = new TextDecoder("windows-1252"));
const headers = this.decoder.decode(view);
this.fileName = headers.substring(0, 100).replace(/\0/g, "");
this.fileSize = parseInt(headers.substring(124, 136), 8);
this.fileType = headers.substring(156, 157);
this.ustarFormat = headers.substring(257, 263);
if (this.ustarFormat.indexOf("ustar") !== -1) {
const prefix = headers.substring(345, 500).replace(/\0/g, "");
if (prefix.length > 0) {
this.fileName = prefix.trim() + this.fileName.trim();
}
}
this.bytesRead += 512;
}
if (this.headerRead) {
if (this.bytesReceived < this.bytesRead + this.fileSize) {
return false;
}
if (this.fileType === "" || this.fileType === "0") {
const dataView = new DataView(this.data.buffer, this.bytesRead, this.fileSize);
const file = {
name: this.prefix + this.fileName,
size: this.fileSize,
data: dataView
};
this.fire("file", file);
}
this.bytesRead += this.fileSize;
this.headerRead = false;
const bytesRemained = this.bytesRead % this.paddingSize;
if (bytesRemained !== 0) {
this.bytesRead += this.paddingSize - bytesRemained;
}
return true;
}
return false;
}
}
export {
Untar
};