You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 

59 lines
1.7 KiB

/*
* base64-arraybuffer
* https://github.com/niklasvh/base64-arraybuffer
*
* Copyright (c) 2012 Niklas von Hertzen
* Licensed under the MIT license.
*/
(function(chars){
"use strict";
exports.encode = function(arraybuffer) {
var bytes = new Uint8Array(arraybuffer),
i, len = bytes.length, base64 = "";
for (i = 0; i < len; i+=3) {
base64 += chars[bytes[i] >> 2];
base64 += chars[((bytes[i] & 3) << 4) | (bytes[i + 1] >> 4)];
base64 += chars[((bytes[i + 1] & 15) << 2) | (bytes[i + 2] >> 6)];
base64 += chars[bytes[i + 2] & 63];
}
if ((len % 3) === 2) {
base64 = base64.substring(0, base64.length - 1) + "=";
} else if (len % 3 === 1) {
base64 = base64.substring(0, base64.length - 2) + "==";
}
return base64;
};
exports.decode = function(base64) {
var bufferLength = base64.length * 0.75,
len = base64.length, i, p = 0,
encoded1, encoded2, encoded3, encoded4;
if (base64[base64.length - 1] === "=") {
bufferLength--;
if (base64[base64.length - 2] === "=") {
bufferLength--;
}
}
var arraybuffer = new ArrayBuffer(bufferLength),
bytes = new Uint8Array(arraybuffer);
for (i = 0; i < len; i+=4) {
encoded1 = chars.indexOf(base64[i]);
encoded2 = chars.indexOf(base64[i+1]);
encoded3 = chars.indexOf(base64[i+2]);
encoded4 = chars.indexOf(base64[i+3]);
bytes[p++] = (encoded1 << 2) | (encoded2 >> 4);
bytes[p++] = ((encoded2 & 15) << 4) | (encoded3 >> 2);
bytes[p++] = ((encoded3 & 3) << 6) | (encoded4 & 63);
}
return arraybuffer;
};
})("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/");