v4.js 883 B

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  1. import native from './native.js';
  2. import rng from './rng.js';
  3. import { unsafeStringify } from './stringify.js';
  4. function v4(options, buf, offset) {
  5. if (native.randomUUID && !buf && !options) {
  6. return native.randomUUID();
  7. }
  8. options = options || {};
  9. const rnds = options.random ?? options.rng?.() ?? rng();
  10. if (rnds.length < 16) {
  11. throw new Error('Random bytes length must be >= 16');
  12. }
  13. rnds[6] = (rnds[6] & 0x0f) | 0x40;
  14. rnds[8] = (rnds[8] & 0x3f) | 0x80;
  15. if (buf) {
  16. offset = offset || 0;
  17. if (offset < 0 || offset + 16 > buf.length) {
  18. throw new RangeError(`UUID byte range ${offset}:${offset + 15} is out of buffer bounds`);
  19. }
  20. for (let i = 0; i < 16; ++i) {
  21. buf[offset + i] = rnds[i];
  22. }
  23. return buf;
  24. }
  25. return unsafeStringify(rnds);
  26. }
  27. export default v4;