You can not select more than 25 topics
			Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
		
		
		
		
		
			
		
			
				
					107 lines
				
				3.5 KiB
			
		
		
			
		
	
	
					107 lines
				
				3.5 KiB
			| 
											3 years ago
										 | "use strict"; | ||
|  | 
 | ||
|  | Object.defineProperty(exports, "__esModule", { | ||
|  |   value: true | ||
|  | }); | ||
|  | exports.default = void 0; | ||
|  | 
 | ||
|  | var _rng = _interopRequireDefault(require("./rng.js")); | ||
|  | 
 | ||
|  | var _stringify = _interopRequireDefault(require("./stringify.js")); | ||
|  | 
 | ||
|  | function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; } | ||
|  | 
 | ||
|  | // **`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 || _nodeId; | ||
|  |   let 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) { | ||
|  |     const seedBytes = options.random || (options.rng || _rng.default)(); | ||
|  | 
 | ||
|  |     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.
 | ||
|  | 
 | ||
|  | 
 | ||
|  |   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.default)(b); | ||
|  | } | ||
|  | 
 | ||
|  | var _default = v1; | ||
|  | exports.default = _default; |