crc32

Incremental CRC-32 checksum. Reversed IEEE 802.3 polynomial (0xEDB88320).

Module crc32 | Source packages/front/fw/src/io/calc/crc32.js | Deps none | Worker-safe yes

Resolve

const Crc32 = runtime.resolve('crc32');
// Returns: constructor (new Crc32())

API

const crc = new Crc32();

Examples

const Crc32 = runtime.resolve('crc32');

// Single pass
const crc = new Crc32();
crc.append(new Uint8Array([72, 101, 108, 108, 111]));
console.log(crc.get().toString(16)); // hex checksum

// Incremental processing (streaming)
const crc2 = new Crc32();
for (const chunk of dataChunks) {
    crc2.append(chunk);
}
const checksum = crc2.get();

Worker Usage

const worker = fw.createWorker(
    function({ libs, args }) {
        const Crc32 = libs.crc32;
        const crc = new Crc32();
        crc.append(new Uint8Array(args[0]));
        self.postMessage(crc.get());
    },
    { dependencies: ['crc32'], args: [Array.from(largeBuffer)] }
);

Notes

• Each new Crc32() instance is independent — no shared internal state.
• get() always returns a unsigned 32-bit integer (via >>> 0).
• Pre-computed lookup table algorithm (256 entries) — fast for large volumes.

See also

• adler32 — Adler-32 alternative (faster, less robust)