|
|
/*! https://mths.be/base64 v1.0.0 by @mathias | MIT license */
|
|
|
;(function(root) {
|
|
|
|
|
|
// Detect free variables `exports`.
|
|
|
var freeExports = typeof exports == 'object' && exports;
|
|
|
|
|
|
// Detect free variable `module`.
|
|
|
var freeModule = typeof module == 'object' && module &&
|
|
|
module.exports == freeExports && module;
|
|
|
|
|
|
/*--------------------------------------------------------------------------*/
|
|
|
|
|
|
var InvalidCharacterError = function(message) {
|
|
|
this.message = message;
|
|
|
};
|
|
|
InvalidCharacterError.prototype = new Error;
|
|
|
InvalidCharacterError.prototype.name = 'InvalidCharacterError';
|
|
|
|
|
|
var error = function(message) {
|
|
|
// Note: the error messages used throughout this file match those used by
|
|
|
// the native `atob`/`btoa` implementation in Chromium.
|
|
|
throw new InvalidCharacterError(message);
|
|
|
};
|
|
|
|
|
|
var TABLE = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
|
|
|
// http://whatwg.org/html/common-microsyntaxes.html#space-character
|
|
|
var REGEX_SPACE_CHARACTERS = /[\t\n\f\r ]/g;
|
|
|
|
|
|
// `decode` is designed to be fully compatible with `atob` as described in the
|
|
|
// HTML Standard. http://whatwg.org/html/webappapis.html#dom-windowbase64-atob
|
|
|
// The optimized base64-decoding algorithm used is based on @atk’s excellent
|
|
|
// implementation. https://gist.github.com/atk/1020396
|
|
|
var decode = function(input) {
|
|
|
input = String(input)
|
|
|
.replace(REGEX_SPACE_CHARACTERS, '');
|
|
|
var length = input.length;
|
|
|
if (length % 4 == 0) {
|
|
|
input = input.replace(/==?$/, '');
|
|
|
length = input.length;
|
|
|
}
|
|
|
if (
|
|
|
length % 4 == 1 ||
|
|
|
// http://whatwg.org/C#alphanumeric-ascii-characters
|
|
|
/[^+a-zA-Z0-9/]/.test(input)
|
|
|
) {
|
|
|
error(
|
|
|
'Invalid character: the string to be decoded is not correctly encoded.'
|
|
|
);
|
|
|
}
|
|
|
var bitCounter = 0;
|
|
|
var bitStorage;
|
|
|
var buffer;
|
|
|
var output = '';
|
|
|
var position = -1;
|
|
|
while (++position < length) {
|
|
|
buffer = TABLE.indexOf(input.charAt(position));
|
|
|
bitStorage = bitCounter % 4 ? bitStorage * 64 + buffer : buffer;
|
|
|
// Unless this is the first of a group of 4 characters…
|
|
|
if (bitCounter++ % 4) {
|
|
|
// …convert the first 8 bits to a single ASCII character.
|
|
|
output += String.fromCharCode(
|
|
|
0xFF & bitStorage >> (-2 * bitCounter & 6)
|
|
|
);
|
|
|
}
|
|
|
}
|
|
|
return output;
|
|
|
};
|
|
|
|
|
|
// `encode` is designed to be fully compatible with `btoa` as described in the
|
|
|
// HTML Standard: http://whatwg.org/html/webappapis.html#dom-windowbase64-btoa
|
|
|
var encode = function(input) {
|
|
|
input = String(input);
|
|
|
if (/[^\0-\xFF]/.test(input)) {
|
|
|
// Note: no need to special-case astral symbols here, as surrogates are
|
|
|
// matched, and the input is supposed to only contain ASCII anyway.
|
|
|
error(
|
|
|
'The string to be encoded contains characters outside of the ' +
|
|
|
'Latin1 range.'
|
|
|
);
|
|
|
}
|
|
|
var padding = input.length % 3;
|
|
|
var output = '';
|
|
|
var position = -1;
|
|
|
var a;
|
|
|
var b;
|
|
|
var c;
|
|
|
var buffer;
|
|
|
// Make sure any padding is handled outside of the loop.
|
|
|
var length = input.length - padding;
|
|
|
|
|
|
while (++position < length) {
|
|
|
// Read three bytes, i.e. 24 bits.
|
|
|
a = input.charCodeAt(position) << 16;
|
|
|
b = input.charCodeAt(++position) << 8;
|
|
|
c = input.charCodeAt(++position);
|
|
|
buffer = a + b + c;
|
|
|
// Turn the 24 bits into four chunks of 6 bits each, and append the
|
|
|
// matching character for each of them to the output.
|
|
|
output += (
|
|
|
TABLE.charAt(buffer >> 18 & 0x3F) +
|
|
|
TABLE.charAt(buffer >> 12 & 0x3F) +
|
|
|
TABLE.charAt(buffer >> 6 & 0x3F) +
|
|
|
TABLE.charAt(buffer & 0x3F)
|
|
|
);
|
|
|
}
|
|
|
|
|
|
if (padding == 2) {
|
|
|
a = input.charCodeAt(position) << 8;
|
|
|
b = input.charCodeAt(++position);
|
|
|
buffer = a + b;
|
|
|
output += (
|
|
|
TABLE.charAt(buffer >> 10) +
|
|
|
TABLE.charAt((buffer >> 4) & 0x3F) +
|
|
|
TABLE.charAt((buffer << 2) & 0x3F) +
|
|
|
'='
|
|
|
);
|
|
|
} else if (padding == 1) {
|
|
|
buffer = input.charCodeAt(position);
|
|
|
output += (
|
|
|
TABLE.charAt(buffer >> 2) +
|
|
|
TABLE.charAt((buffer << 4) & 0x3F) +
|
|
|
'=='
|
|
|
);
|
|
|
}
|
|
|
|
|
|
return output;
|
|
|
};
|
|
|
|
|
|
var base64 = {
|
|
|
'encode': encode,
|
|
|
'decode': decode,
|
|
|
'version': '1.0.0'
|
|
|
};
|
|
|
|
|
|
// Some AMD build optimizers, like r.js, check for specific condition patterns
|
|
|
// like the following:
|
|
|
if (
|
|
|
typeof define == 'function' &&
|
|
|
typeof define.amd == 'object' &&
|
|
|
define.amd
|
|
|
) {
|
|
|
define(function() {
|
|
|
return base64;
|
|
|
});
|
|
|
} else if (freeExports && !freeExports.nodeType) {
|
|
|
if (freeModule) { // in Node.js or RingoJS v0.8.0+
|
|
|
freeModule.exports = base64;
|
|
|
} else { // in Narwhal or RingoJS v0.7.0-
|
|
|
for (var key in base64) {
|
|
|
base64.hasOwnProperty(key) && (freeExports[key] = base64[key]);
|
|
|
}
|
|
|
}
|
|
|
} else { // in Rhino or a web browser
|
|
|
root.base64 = base64;
|
|
|
}
|
|
|
|
|
|
}(this));
|