171 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			171 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| /*!
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|  * bytes
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|  * Copyright(c) 2012-2014 TJ Holowaychuk
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|  * Copyright(c) 2015 Jed Watson
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|  * MIT Licensed
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|  */
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| 
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| 'use strict';
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| 
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| /**
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|  * Module exports.
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|  * @public
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|  */
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| 
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| module.exports = bytes;
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| module.exports.format = format;
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| module.exports.parse = parse;
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| 
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| /**
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|  * Module variables.
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|  * @private
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|  */
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| 
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| var formatThousandsRegExp = /\B(?=(\d{3})+(?!\d))/g;
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| 
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| var formatDecimalsRegExp = /(?:\.0*|(\.[^0]+)0+)$/;
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| 
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| var map = {
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|   b:  1,
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|   kb: 1 << 10,
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|   mb: 1 << 20,
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|   gb: 1 << 30,
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|   tb: Math.pow(1024, 4),
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|   pb: Math.pow(1024, 5),
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| };
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| 
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| var parseRegExp = /^((-|\+)?(\d+(?:\.\d+)?)) *(kb|mb|gb|tb|pb)$/i;
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| 
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| /**
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|  * Convert the given value in bytes into a string or parse to string to an integer in bytes.
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|  *
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|  * @param {string|number} value
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|  * @param {{
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|  *  case: [string],
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|  *  decimalPlaces: [number]
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|  *  fixedDecimals: [boolean]
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|  *  thousandsSeparator: [string]
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|  *  unitSeparator: [string]
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|  *  }} [options] bytes options.
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|  *
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|  * @returns {string|number|null}
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|  */
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| 
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| function bytes(value, options) {
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|   if (typeof value === 'string') {
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|     return parse(value);
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|   }
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| 
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|   if (typeof value === 'number') {
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|     return format(value, options);
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|   }
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| 
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|   return null;
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| }
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| 
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| /**
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|  * Format the given value in bytes into a string.
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|  *
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|  * If the value is negative, it is kept as such. If it is a float,
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|  * it is rounded.
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|  *
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|  * @param {number} value
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|  * @param {object} [options]
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|  * @param {number} [options.decimalPlaces=2]
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|  * @param {number} [options.fixedDecimals=false]
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|  * @param {string} [options.thousandsSeparator=]
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|  * @param {string} [options.unit=]
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|  * @param {string} [options.unitSeparator=]
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|  *
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|  * @returns {string|null}
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|  * @public
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|  */
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| 
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| function format(value, options) {
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|   if (!Number.isFinite(value)) {
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|     return null;
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|   }
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| 
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|   var mag = Math.abs(value);
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|   var thousandsSeparator = (options && options.thousandsSeparator) || '';
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|   var unitSeparator = (options && options.unitSeparator) || '';
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|   var decimalPlaces = (options && options.decimalPlaces !== undefined) ? options.decimalPlaces : 2;
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|   var fixedDecimals = Boolean(options && options.fixedDecimals);
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|   var unit = (options && options.unit) || '';
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| 
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|   if (!unit || !map[unit.toLowerCase()]) {
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|     if (mag >= map.pb) {
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|       unit = 'PB';
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|     } else if (mag >= map.tb) {
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|       unit = 'TB';
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|     } else if (mag >= map.gb) {
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|       unit = 'GB';
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|     } else if (mag >= map.mb) {
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|       unit = 'MB';
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|     } else if (mag >= map.kb) {
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|       unit = 'KB';
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|     } else {
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|       unit = 'B';
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|     }
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|   }
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| 
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|   var val = value / map[unit.toLowerCase()];
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|   var str = val.toFixed(decimalPlaces);
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| 
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|   if (!fixedDecimals) {
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|     str = str.replace(formatDecimalsRegExp, '$1');
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|   }
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| 
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|   if (thousandsSeparator) {
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|     str = str.split('.').map(function (s, i) {
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|       return i === 0
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|         ? s.replace(formatThousandsRegExp, thousandsSeparator)
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|         : s
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|     }).join('.');
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|   }
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| 
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|   return str + unitSeparator + unit;
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| }
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| 
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| /**
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|  * Parse the string value into an integer in bytes.
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|  *
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|  * If no unit is given, it is assumed the value is in bytes.
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|  *
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|  * @param {number|string} val
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|  *
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|  * @returns {number|null}
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|  * @public
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|  */
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| 
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| function parse(val) {
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|   if (typeof val === 'number' && !isNaN(val)) {
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|     return val;
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|   }
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| 
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|   if (typeof val !== 'string') {
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|     return null;
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|   }
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| 
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|   // Test if the string passed is valid
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|   var results = parseRegExp.exec(val);
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|   var floatValue;
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|   var unit = 'b';
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| 
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|   if (!results) {
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|     // Nothing could be extracted from the given string
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|     floatValue = parseInt(val, 10);
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|     unit = 'b'
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|   } else {
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|     // Retrieve the value and the unit
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|     floatValue = parseFloat(results[1]);
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|     unit = results[4].toLowerCase();
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|   }
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| 
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|   if (isNaN(floatValue)) {
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|     return null;
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|   }
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| 
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|   return Math.floor(map[unit] * floatValue);
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| }
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