Mercurial > eldonilo > lightstring

comparison base64.js @ 0:96898e3812a5

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
initial push
author Sonny Piers <sonny.piers@gmail.com>
date Sun, 18 Dec 2011 19:03:28 +0100
parents
children
comparison
equal deleted inserted replaced
-1:000000000000 0:96898e3812a5
1 // This code was written by Tyler Akins and has been placed in the
2 // public domain. It would be nice if you left this header intact.
3 // Base64 code from Tyler Akins -- http://rumkin.com
4
5 var Base64 = (function () {
6 var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
7
8 var obj = {
9 /**
10 * Encodes a string in base64
11 * @param {String} input The string to encode in base64.
12 */
13 encode: function (input) {
14 var output = "";
15 var chr1, chr2, chr3;
16 var enc1, enc2, enc3, enc4;
17 var i = 0;
18
19 do {
20 chr1 = input.charCodeAt(i++);
21 chr2 = input.charCodeAt(i++);
22 chr3 = input.charCodeAt(i++);
23
24 enc1 = chr1 >> 2;
25 enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
26 enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
27 enc4 = chr3 & 63;
28
29 if (isNaN(chr2)) {
30 enc3 = enc4 = 64;
31 } else if (isNaN(chr3)) {
32 enc4 = 64;
33 }
34
35 output = output + keyStr.charAt(enc1) + keyStr.charAt(enc2) +
36 keyStr.charAt(enc3) + keyStr.charAt(enc4);
37 } while (i < input.length);
38
39 return output;
40 },
41
42 /**
43 * Decodes a base64 string.
44 * @param {String} input The string to decode.
45 */
46 decode: function (input) {
47 var output = "";
48 var chr1, chr2, chr3;
49 var enc1, enc2, enc3, enc4;
50 var i = 0;
51
52 // remove all characters that are not A-Z, a-z, 0-9, +, /, or =
53 input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
54
55 do {
56 enc1 = keyStr.indexOf(input.charAt(i++));
57 enc2 = keyStr.indexOf(input.charAt(i++));
58 enc3 = keyStr.indexOf(input.charAt(i++));
59 enc4 = keyStr.indexOf(input.charAt(i++));
60
61 chr1 = (enc1 << 2) | (enc2 >> 4);
62 chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
63 chr3 = ((enc3 & 3) << 6) | enc4;
64
65 output = output + String.fromCharCode(chr1);
66
67 if (enc3 != 64) {
68 output = output + String.fromCharCode(chr2);
69 }
70 if (enc4 != 64) {
71 output = output + String.fromCharCode(chr3);
72 }
73 } while (i < input.length);
74
75 return output;
76 }
77 };
78
79 return obj;
80 })();