1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 /** @fileoverview Various string utility functions */ 6 'use strict'; 7 8 /** 9 * Converts a string to an array of bytes. 10 * @param {string} s The string to convert. 11 * @param {(Array|Uint8Array)=} bytes The Array-like object into which to store 12 * the bytes. A new Array will be created if not provided. 13 * @return {(Array|Uint8Array)} An array of bytes representing the string. 14 */ 15 function UTIL_StringToBytes(s, bytes) { 16 bytes = bytes || new Array(s.length); 17 for (var i = 0; i < s.length; ++i) 18 bytes[i] = s.charCodeAt(i); 19 return bytes; 20 } 21 22 function UTIL_BytesToString(b) { 23 return String.fromCharCode.apply(null, b); 24 } 25 26 function UTIL_BytesToHex(b) { 27 if (!b) return '(null)'; 28 var hexchars = '0123456789ABCDEF'; 29 var hexrep = new Array(b.length * 2); 30 31 for (var i = 0; i < b.length; ++i) { 32 hexrep[i * 2 + 0] = hexchars.charAt((b[i] >> 4) & 15); 33 hexrep[i * 2 + 1] = hexchars.charAt(b[i] & 15); 34 } 35 return hexrep.join(''); 36 } 37 38 function UTIL_BytesToHexWithSeparator(b, sep) { 39 var hexchars = '0123456789ABCDEF'; 40 var stride = 2 + (sep ? 1 : 0); 41 var hexrep = new Array(b.length * stride); 42 43 for (var i = 0; i < b.length; ++i) { 44 if (sep) hexrep[i * stride + 0] = sep; 45 hexrep[i * stride + stride - 2] = hexchars.charAt((b[i] >> 4) & 15); 46 hexrep[i * stride + stride - 1] = hexchars.charAt(b[i] & 15); 47 } 48 return (sep ? hexrep.slice(1) : hexrep).join(''); 49 } 50 51 function UTIL_HexToBytes(h) { 52 var hexchars = '0123456789ABCDEFabcdef'; 53 var res = new Uint8Array(h.length / 2); 54 for (var i = 0; i < h.length; i += 2) { 55 if (hexchars.indexOf(h.substring(i, i + 1)) == -1) break; 56 res[i / 2] = parseInt(h.substring(i, i + 2), 16); 57 } 58 return res; 59 } 60 61 function UTIL_equalArrays(a, b) { 62 if (!a || !b) return false; 63 if (a.length != b.length) return false; 64 var accu = 0; 65 for (var i = 0; i < a.length; ++i) 66 accu |= a[i] ^ b[i]; 67 return accu === 0; 68 } 69 70 function UTIL_ltArrays(a, b) { 71 if (a.length < b.length) return true; 72 if (a.length > b.length) return false; 73 for (var i = 0; i < a.length; ++i) { 74 if (a[i] < b[i]) return true; 75 if (a[i] > b[i]) return false; 76 } 77 return false; 78 } 79 80 function UTIL_gtArrays(a, b) { 81 return UTIL_ltArrays(b, a); 82 } 83 84 function UTIL_geArrays(a, b) { 85 return !UTIL_ltArrays(a, b); 86 } 87 88 function UTIL_unionArrays(a, b) { 89 var obj = {}; 90 for (var i = 0; i < a.length; i++) { 91 obj[a[i]] = a[i]; 92 } 93 for (var i = 0; i < b.length; i++) { 94 obj[b[i]] = b[i]; 95 } 96 var union = []; 97 for (var k in obj) { 98 union.push(obj[k]); 99 } 100 return union; 101 } 102 103 function UTIL_getRandom(a) { 104 var tmp = new Array(a); 105 var rnd = new Uint8Array(a); 106 window.crypto.getRandomValues(rnd); // Yay! 107 for (var i = 0; i < a; ++i) tmp[i] = rnd[i] & 255; 108 return tmp; 109 } 110 111 function UTIL_setFavicon(icon) { 112 // Construct a new favion link tag 113 var faviconLink = document.createElement('link'); 114 faviconLink.rel = 'Shortcut Icon'; 115 faviconLink.type = 'image/x-icon'; 116 faviconLink.href = icon; 117 118 // Remove the old favion, if it exists 119 var head = document.getElementsByTagName('head')[0]; 120 var links = head.getElementsByTagName('link'); 121 for (var i = 0; i < links.length; i++) { 122 var link = links[i]; 123 if (link.type == faviconLink.type && link.rel == faviconLink.rel) { 124 head.removeChild(link); 125 } 126 } 127 128 // Add in the new one 129 head.appendChild(faviconLink); 130 } 131 132 // Erase all entries in array 133 function UTIL_clear(a) { 134 if (a instanceof Array) { 135 for (var i = 0; i < a.length; ++i) 136 a[i] = 0; 137 } 138 } 139 140 // hr:min:sec.milli string 141 function UTIL_time() { 142 var d = new Date(); 143 var m = '000' + d.getMilliseconds(); 144 var s = d.toTimeString().substring(0, 8) + '.' + m.substring(m.length - 3); 145 return s; 146 } 147 var UTIL_events = []; 148 var UTIL_max_events = 500; 149 150 function UTIL_fmt(s) { 151 var line = UTIL_time() + ' ' + s; 152 if (UTIL_events.push(line) > UTIL_max_events) { 153 // Drop from head. 154 UTIL_events.splice(0, UTIL_events.length - UTIL_max_events); 155 } 156 return line; 157 } 158
