/*
* constructed via browserfy and hand edited to declare exports
*
* /usr/local/bin/browserify node-uuid/v1.js -o v1-uuid.js
*/
var byteToHex = [];
for (var i = 0; i < 256; ++i) {
byteToHex[i] = (i + 0x100).toString(16).substr(1);
}
/**
* Convert array of 16 byte values to UUID string format of the form:
* XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX
*/
export function bytesToUuid(buf, offset) {
var i = offset || 0;
var bth = byteToHex;
// join used to fix memory issue caused by concatenation: https://bugs.chromium.org/p/v8/issues/detail?id=3175#c4
return ([bth[buf[i++]], bth[buf[i++]],
bth[buf[i++]], bth[buf[i++]], '-',
bth[buf[i++]], bth[buf[i++]], '-',
bth[buf[i++]], bth[buf[i++]], '-',
bth[buf[i++]], bth[buf[i++]], '-',
bth[buf[i++]], bth[buf[i++]],
bth[buf[i++]], bth[buf[i++]],
bth[buf[i++]], bth[buf[i++]]]).join('');
}
// Unique ID creation requires a high quality random # generator. In the
// browser this is a little complicated due to unknown quality of Math.random()
// and inconsistent support for the `crypto` API. We do the best we can via
// feature-detection
// getRandomValues needs to be invoked in a context where "this" is a Crypto
// implementation. Also, find the complete implementation of crypto on IE11.
var getRandomValues = (typeof(crypto) != 'undefined' && crypto.getRandomValues && crypto.getRandomValues.bind(crypto)) ||
(typeof(msCrypto) != 'undefined' && typeof window.msCrypto.getRandomValues == 'function' && msCrypto.getRandomValues.bind(msCrypto));
export var rng = null;
if (getRandomValues) {
// WHATWG crypto RNG - http://wiki.whatwg.org/wiki/Crypto
var rnds8 = new Uint8Array(16); // eslint-disable-line no-undef
rng = function whatwgRNG() {
getRandomValues(rnds8);
return rnds8;
};
} else {
// Math.random()-based (RNG)
//
// If all else fails, use Math.random(). It's fast, but is of unspecified
// quality.
var rnds = new Array(16);
rng = function mathRNG() {
for (var i = 0, r; i < 16; i++) {
if ((i & 0x03) === 0) r = Math.random() * 0x100000000;
rnds[i] = r >>> ((i & 0x03) << 3) & 0xff;
}
return rnds;
};
}
// **`v1()` - Generate time-based UUID**
//
// Inspired by https://github.com/LiosK/UUID.js
// and http://docs.python.org/library/uuid.html
var _nodeId;
var _clockseq;
// Previous uuid creation time
var _lastMSecs = 0;
var _lastNSecs = 0;
// See https://github.com/broofa/node-uuid for API details
/**
Compute a v1 UUID
Given a buffer use that to construct the value and return it.
Absent a buffer, create a temporarx for construction, but translate
the result into hex-encoded-string and return that.
*/
export function v1(options, buf, offset) {
var i = buf && offset || 0;
var b = buf || [];
options = options || {};
var node = options.node || _nodeId;
var clockseq = options.clockseq !== undefined ? options.clockseq : _clockseq;
// node and clockseq need to be initialized to random values if they're not
// specified. We do this lazily to minimize issues related to insufficient
// system entropy. See #189
if (node == null || clockseq == null) {
var seedBytes = rng();
if (node == null) {
// Per 4.5, create and 48-bit node id, (47 random bits + multicast bit = 1)
node = _nodeId = [
seedBytes[0] | 0x01,
seedBytes[1], seedBytes[2], seedBytes[3], seedBytes[4], seedBytes[5]
];
}
if (clockseq == null) {
// Per 4.2.2, randomize (14 bit) clockseq
clockseq = _clockseq = (seedBytes[6] << 8 | seedBytes[7]) & 0x3fff;
}
}
// UUID 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.
var msecs = options.msecs !== undefined ? options.msecs : new Date().getTime();
// Per 4.2.1.2, use count of uuid's generated during the current clock
// cycle to simulate higher resolution clock
var nsecs = options.nsecs !== undefined ? options.nsecs : _lastNSecs + 1;
// Time since last uuid creation (in msecs)
var 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`
var 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`
var 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 (var n = 0; n < 6; ++n) {
b[i + n] = node[n];
}
return buf ? buf : bytesToUuid(b);
}
Source