firebase-tools
Version:
Command-Line Interface for Firebase
34 lines (33 loc) • 1.02 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.crc32cToString = exports.crc32c = void 0;
function makeCRCTable(poly) {
let c;
const crcTable = [];
for (let n = 0; n < 256; n++) {
c = n;
for (let k = 0; k < 8; k++) {
c = c & 1 ? poly ^ (c >>> 1) : c >>> 1;
}
crcTable[n] = c;
}
return crcTable;
}
const CRC32C_TABLE = makeCRCTable(0x82f63b78);
function crc32c(bytes) {
let crc = 0 ^ -1;
for (let i = 0; i < bytes.length; i++) {
const byte = bytes[i];
const nLookupIndex = (crc ^ byte) & 0xff;
crc = (crc >>> 8) ^ CRC32C_TABLE[nLookupIndex];
}
return (crc ^ -1) >>> 0;
}
exports.crc32c = crc32c;
function crc32cToString(crc32cValue) {
const value = typeof crc32cValue === "string" ? Number.parseInt(crc32cValue) : crc32cValue;
const buffer = Buffer.alloc(4);
buffer.writeUint32BE(value);
return buffer.toString("base64");
}
exports.crc32cToString = crc32cToString;