webpack/lib/util/hash/xxhash64.js

Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/

"use strict";

//#region wasm code: xxhash64 (../../../assembly/hash/xxhash64.asm.ts) --initialMemory 1
const xxhash64 = new WebAssembly.Module(
	Buffer.from(
		// 1180 bytes
		"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",
		"base64"
	)
);
//#endregion

class XxHash64 {
	/**
	 * @param {WebAssembly.Instance} instance wasm instance
	 */
	constructor(instance) {
		const exports = /** @type {any} */ (instance.exports);
		exports.init();
		this.exports = exports;
		this.mem = Buffer.from(exports.memory.buffer, 0, 65536);
		this.buffered = 0;
	}

	reset() {
		this.buffered = 0;
		this.exports.init();
	}

	/**
	 * @param {Buffer | string} data data
	 * @param {BufferEncoding=} encoding encoding
	 * @returns {this} itself
	 */
	update(data, encoding) {
		if (typeof data === "string") {
			if (data.length < 21845) {
				this._updateWithShortString(data, encoding);
				return this;
			} else {
				data = Buffer.from(data, encoding);
			}
		}
		this._updateWithBuffer(data);
		return this;
	}

	/**
	 * @param {string} data data
	 * @param {BufferEncoding=} encoding encoding
	 * @returns {void}
	 */
	_updateWithShortString(data, encoding) {
		const { exports, buffered, mem } = this;
		let endPos;
		if (data.length < 70) {
			if (!encoding || encoding === "utf-8" || encoding === "utf8") {
				endPos = buffered;
				for (let i = 0; i < data.length; i++) {
					const cc = data.charCodeAt(i);
					if (cc < 0x80) mem[endPos++] = cc;
					else if (cc < 0x800) {
						mem[endPos] = (cc >> 6) | 0xc0;
						mem[endPos + 1] = (cc & 0x3f) | 0x80;
						endPos += 2;
					} else {
						// bail-out for weird chars
						endPos += mem.write(data.slice(endPos), endPos, encoding);
						break;
					}
				}
			} else if (encoding === "latin1") {
				endPos = buffered;
				for (let i = 0; i < data.length; i++) {
					const cc = data.charCodeAt(i);
					mem[endPos++] = cc;
				}
			} else {
				endPos = buffered + mem.write(data, buffered, encoding);
			}
		} else {
			endPos = buffered + mem.write(data, buffered, encoding);
		}
		if (endPos < 32) {
			this.buffered = endPos;
		} else {
			const l = (endPos >> 5) << 5;
			exports.update(l);
			const newBuffered = endPos - l;
			this.buffered = newBuffered;
			if (newBuffered > 0) mem.copyWithin(0, l, endPos);
		}
	}

	/**
	 * @param {Buffer} data data
	 * @returns {void}
	 */
	_updateWithBuffer(data) {
		const { exports, buffered, mem } = this;
		const length = data.length;
		if (buffered + length < 32) {
			data.copy(mem, buffered, 0, length);
			this.buffered += length;
		} else {
			const l = ((buffered + length) >> 5) << 5;
			if (l > 65536) {
				let i = 65536 - buffered;
				data.copy(mem, buffered, 0, i);
				exports.update(65536);
				const stop = l - buffered - 65536;
				while (i < stop) {
					data.copy(mem, 0, i, i + 65536);
					exports.update(65536);
					i += 65536;
				}
				data.copy(mem, 0, i, l - buffered);
				exports.update(l - buffered - i);
			} else {
				data.copy(mem, buffered, 0, l - buffered);
				exports.update(l);
			}
			const newBuffered = length + buffered - l;
			this.buffered = newBuffered;
			if (newBuffered > 0) data.copy(mem, 0, length - newBuffered, length);
		}
	}

	digest(type) {
		const { exports, buffered, mem } = this;
		exports.final(buffered);
		instancesPool.push(this);
		return mem.toString("latin1", 0, 16);
	}
}

const instancesPool = [];

const create = () => {
	if (instancesPool.length > 0) {
		const old = instancesPool.pop();
		old.reset();
		return old;
	} else {
		return new XxHash64(new WebAssembly.Instance(xxhash64));
	}
};

module.exports = create;