var rng = require('./lib/rng'); var bytesToUuid = require('./lib/bytesToUuid'); function v4(options, buf, offset) { var i = buf && offset || 0; if (typeof(options) == 'string') { buf = options === 'binary' ? new Array(16) : null; options = null; } options = options || {}; var rnds = options.random || (options.rng || rng)(); // Per 4.4, set bits for version and `clock_seq_hi_and_reserved` rnds[6] = (rnds[6] & 0x0f) | 0x40; rnds[8] = (rnds[8] & 0x3f) | 0x80; // Copy bytes to buffer, if provided if (buf) { for (var ii = 0; ii < 16; ++ii) { buf[i + ii] = rnds[ii]; } } return buf || bytesToUuid(rnds); } module.exports = v4;