agsamantha/node_modules/uuid/dist/v1.js
2024-10-02 15:15:21 -05:00

131 lines
No EOL
3.8 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = void 0;
var _rng = _interopRequireDefault(require("./rng.js"));
var _stringify = require("./stringify.js");
function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; }
// **`v1()` - Generate time-based UUID**
//
// Inspired by https://github.com/LiosK/UUID.js
// and http://docs.python.org/library/uuid.html
let _nodeId;
let _clockseq;
// Previous uuid creation time
let _lastMSecs = 0;
let _lastNSecs = 0;
// See https://github.com/uuidjs/uuid for API details
function v1(options, buf, offset) {
let i = buf && offset || 0;
const b = buf || new Array(16);
options = options || {};
let node = options.node;
let clockseq = options.clockseq;
// v1 only: Use cached `node` and `clockseq` values
if (!options._v6) {
if (!node) {
node = _nodeId;
}
if (clockseq == null) {
clockseq = _clockseq;
}
}
// Handle cases where we need entropy. We do this lazily to minimize issues
// related to insufficient system entropy. See #189
if (node == null || clockseq == null) {
const seedBytes = options.random || (options.rng || _rng.default)();
// Randomize node
if (node == null) {
node = [seedBytes[0], seedBytes[1], seedBytes[2], seedBytes[3], seedBytes[4], seedBytes[5]];
// v1 only: cache node value for reuse
if (!_nodeId && !options._v6) {
// per RFC4122 4.5: Set MAC multicast bit (v1 only)
node[0] |= 0x01; // Set multicast bit
_nodeId = node;
}
}
// Randomize clockseq
if (clockseq == null) {
// Per 4.2.2, randomize (14 bit) clockseq
clockseq = (seedBytes[6] << 8 | seedBytes[7]) & 0x3fff;
if (_clockseq === undefined && !options._v6) {
_clockseq = clockseq;
}
}
}
// v1 & v6 timestamps are 100 nano-second units since the Gregorian epoch,
// (1582-10-15 00:00). JSNumbers aren't precise enough for this, so time is
// handled internally as 'msecs' (integer milliseconds) and 'nsecs'
// (100-nanoseconds offset from msecs) since unix epoch, 1970-01-01 00:00.
let msecs = options.msecs !== undefined ? options.msecs : Date.now();
// Per 4.2.1.2, use count of uuid's generated during the current clock
// cycle to simulate higher resolution clock
let nsecs = options.nsecs !== undefined ? options.nsecs : _lastNSecs + 1;
// Time since last uuid creation (in msecs)
const dt = msecs - _lastMSecs + (nsecs - _lastNSecs) / 10000;
// Per 4.2.1.2, Bump clockseq on clock regression
if (dt < 0 && options.clockseq === undefined) {
clockseq = clockseq + 1 & 0x3fff;
}
// Reset nsecs if clock regresses (new clockseq) or we've moved onto a new
// time interval
if ((dt < 0 || msecs > _lastMSecs) && options.nsecs === undefined) {
nsecs = 0;
}
// Per 4.2.1.2 Throw error if too many uuids are requested
if (nsecs >= 10000) {
throw new Error("uuid.v1(): Can't create more than 10M uuids/sec");
}
_lastMSecs = msecs;
_lastNSecs = nsecs;
_clockseq = clockseq;
// Per 4.1.4 - Convert from unix epoch to Gregorian epoch
msecs += 12219292800000;
// `time_low`
const tl = ((msecs & 0xfffffff) * 10000 + nsecs) % 0x100000000;
b[i++] = tl >>> 24 & 0xff;
b[i++] = tl >>> 16 & 0xff;
b[i++] = tl >>> 8 & 0xff;
b[i++] = tl & 0xff;
// `time_mid`
const tmh = msecs / 0x100000000 * 10000 & 0xfffffff;
b[i++] = tmh >>> 8 & 0xff;
b[i++] = tmh & 0xff;
// `time_high_and_version`
b[i++] = tmh >>> 24 & 0xf | 0x10; // include version
b[i++] = tmh >>> 16 & 0xff;
// `clock_seq_hi_and_reserved` (Per 4.2.2 - include variant)
b[i++] = clockseq >>> 8 | 0x80;
// `clock_seq_low`
b[i++] = clockseq & 0xff;
// `node`
for (let n = 0; n < 6; ++n) {
b[i + n] = node[n];
}
return buf || (0, _stringify.unsafeStringify)(b);
}
var _default = exports.default = v1;