const MAX_SHORT_STRING = require("./wasm-hash").MAX_SHORT_STRING; class BatchedHash { constructor(hash) { this.string = undefined; this.encoding = undefined; this.hash = hash; } /** * 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 (this.string !== undefined) { if ( typeof data === "string" && inputEncoding === this.encoding && this.string.length + data.length < MAX_SHORT_STRING ) { this.string += data; return this; } this.hash.update(this.string, this.encoding); this.string = undefined; } if (typeof data === "string") { if ( data.length < MAX_SHORT_STRING && // base64 encoding is not valid since it may contain padding chars (!inputEncoding || !inputEncoding.startsWith("ba")) ) { this.string = data; this.encoding = inputEncoding; } else { this.hash.update(data, inputEncoding); } } else { this.hash.update(data); } 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) { if (this.string !== undefined) { this.hash.update(this.string, this.encoding); } return this.hash.digest(encoding); } } module.exports = BatchedHash;