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base64.js
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base64.js
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// Base64 JavaScript decoder
// Copyright (c) 2008-2014 Lapo Luchini <[email protected]>
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
/*jshint browser: true, strict: true, immed: true, latedef: true, undef: true, regexdash: false */
(function (undefined) {
"use strict";
var Base64 = {},
decoder;
Base64.decode = function (a) {
var i;
if (decoder === undefined) {
var b64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/",
ignore = "= \f\n\r\t\u00A0\u2028\u2029";
decoder = [];
for (i = 0; i < 64; ++i)
decoder[b64.charAt(i)] = i;
for (i = 0; i < ignore.length; ++i)
decoder[ignore.charAt(i)] = -1;
}
var out = [];
var bits = 0, char_count = 0;
for (i = 0; i < a.length; ++i) {
var c = a.charAt(i);
if (c == '=')
break;
c = decoder[c];
if (c == -1)
continue;
if (c === undefined)
throw 'Illegal character at offset ' + i;
bits |= c;
if (++char_count >= 4) {
out[out.length] = (bits >> 16);
out[out.length] = (bits >> 8) & 0xFF;
out[out.length] = bits & 0xFF;
bits = 0;
char_count = 0;
} else {
bits <<= 6;
}
}
switch (char_count) {
case 1:
throw "Base64 encoding incomplete: at least 2 bits missing";
case 2:
out[out.length] = (bits >> 10);
break;
case 3:
out[out.length] = (bits >> 16);
out[out.length] = (bits >> 8) & 0xFF;
break;
}
return out;
};
Base64.re = /-----BEGIN [^-]+-----([A-Za-z0-9+\/=\s]+)-----END [^-]+-----|begin-base64[^\n]+\n([A-Za-z0-9+\/=\s]+)====/;
Base64.unarmor = function (a) {
var m = Base64.re.exec(a);
if (m) {
if (m[1])
a = m[1];
else if (m[2])
a = m[2];
else
throw "RegExp out of sync";
}
return Base64.decode(a);
};
// export globals
if (typeof module !== 'undefined') { module.exports = Base64; } else { window.Base64 = Base64; }
})();