gree_leran/node_modules/webpack/lib/util/createHash.js

194 lines
5.5 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const Hash = require("./Hash");
const BULK_SIZE = 2000;
// We are using an object instead of a Map as this will stay static during the runtime
// so access to it can be optimized by v8
/** @type {Object<string, Map<string, string>>} */
const digestCaches = {};
/** @typedef {function(): Hash} HashFactory */
class BulkUpdateDecorator extends Hash {
/**
* @param {Hash | HashFactory} hashOrFactory function to create a hash
* @param {string=} hashKey key for caching
*/
constructor(hashOrFactory, hashKey) {
super();
this.hashKey = hashKey;
if (typeof hashOrFactory === "function") {
this.hashFactory = hashOrFactory;
this.hash = undefined;
} else {
this.hashFactory = undefined;
this.hash = hashOrFactory;
}
this.buffer = "";
}
/**
* Update hash {@link https://nodejs.org/api/crypto.html#crypto_hash_update_data_inputencoding}
* @param {string|Buffer} data data
* @param {string=} inputEncoding data encoding
* @returns {this} updated hash
*/
update(data, inputEncoding) {
if (
inputEncoding !== undefined ||
typeof data !== "string" ||
data.length > BULK_SIZE
) {
if (this.hash === undefined)
this.hash = /** @type {HashFactory} */ (this.hashFactory)();
if (this.buffer.length > 0) {
this.hash.update(this.buffer);
this.buffer = "";
}
this.hash.update(data, inputEncoding);
} else {
this.buffer += data;
if (this.buffer.length > BULK_SIZE) {
if (this.hash === undefined)
this.hash = /** @type {HashFactory} */ (this.hashFactory)();
this.hash.update(this.buffer);
this.buffer = "";
}
}
return this;
}
/**
* Calculates the digest {@link https://nodejs.org/api/crypto.html#crypto_hash_digest_encoding}
* @param {string=} encoding encoding of the return value
* @returns {string|Buffer} digest
*/
digest(encoding) {
let digestCache;
const buffer = this.buffer;
if (this.hash === undefined) {
// short data for hash, we can use caching
const cacheKey = `${this.hashKey}-${encoding}`;
digestCache = digestCaches[cacheKey];
if (digestCache === undefined) {
digestCache = digestCaches[cacheKey] = new Map();
}
const cacheEntry = digestCache.get(buffer);
if (cacheEntry !== undefined) return cacheEntry;
this.hash = /** @type {HashFactory} */ (this.hashFactory)();
}
if (buffer.length > 0) {
this.hash.update(buffer);
}
const digestResult = this.hash.digest(encoding);
const result =
typeof digestResult === "string" ? digestResult : digestResult.toString();
if (digestCache !== undefined) {
digestCache.set(buffer, result);
}
return result;
}
}
/* istanbul ignore next */
class DebugHash extends Hash {
constructor() {
super();
this.string = "";
}
/**
* Update hash {@link https://nodejs.org/api/crypto.html#crypto_hash_update_data_inputencoding}
* @param {string|Buffer} data data
* @param {string=} inputEncoding data encoding
* @returns {this} updated hash
*/
update(data, inputEncoding) {
if (typeof data !== "string") data = data.toString("utf-8");
const prefix = Buffer.from("@webpack-debug-digest@").toString("hex");
if (data.startsWith(prefix)) {
data = Buffer.from(data.slice(prefix.length), "hex").toString();
}
this.string += `[${data}](${
/** @type {string} */ (new Error().stack).split("\n", 3)[2]
})\n`;
return this;
}
/**
* Calculates the digest {@link https://nodejs.org/api/crypto.html#crypto_hash_digest_encoding}
* @param {string=} encoding encoding of the return value
* @returns {string|Buffer} digest
*/
digest(encoding) {
return Buffer.from("@webpack-debug-digest@" + this.string).toString("hex");
}
}
/** @type {typeof import("crypto") | undefined} */
let crypto = undefined;
/** @type {typeof import("./hash/xxhash64") | undefined} */
let createXXHash64 = undefined;
/** @type {typeof import("./hash/md4") | undefined} */
let createMd4 = undefined;
/** @type {typeof import("./hash/BatchedHash") | undefined} */
let BatchedHash = undefined;
/**
* Creates a hash by name or function
* @param {string | typeof Hash | undefined} algorithm the algorithm name or a constructor creating a hash
* @returns {Hash} the hash
*/
module.exports = algorithm => {
if (typeof algorithm === "function") {
return new BulkUpdateDecorator(() => new algorithm());
}
switch (algorithm) {
// TODO add non-cryptographic algorithm here
case "debug":
return new DebugHash();
case "xxhash64":
if (createXXHash64 === undefined) {
createXXHash64 = require("./hash/xxhash64");
if (BatchedHash === undefined) {
BatchedHash = require("./hash/BatchedHash");
}
}
return new /** @type {typeof import("./hash/BatchedHash")} */ (
BatchedHash
)(createXXHash64());
case "md4":
if (createMd4 === undefined) {
createMd4 = require("./hash/md4");
if (BatchedHash === undefined) {
BatchedHash = require("./hash/BatchedHash");
}
}
return new /** @type {typeof import("./hash/BatchedHash")} */ (
BatchedHash
)(createMd4());
case "native-md4":
if (crypto === undefined) crypto = require("crypto");
return new BulkUpdateDecorator(
() => /** @type {typeof import("crypto")} */ (crypto).createHash("md4"),
"md4"
);
default:
if (crypto === undefined) crypto = require("crypto");
return new BulkUpdateDecorator(
() =>
/** @type {typeof import("crypto")} */ (crypto).createHash(
/** @type {string} */ (algorithm)
),
algorithm
);
}
};