Permalink
Browse files

Switched base64 to different impl

  • Loading branch information...
1 parent 0c0792a commit 190afc48aaf0f829278d4abce4fe675a199d699b @kriszyp kriszyp committed Jun 24, 2010
Showing with 99 additions and 58 deletions.
  1. +99 −58 lib/base64.js
View
157 lib/base64.js
@@ -1,60 +1,101 @@
-var p="=";
-var tab="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
-
-exports.encode=function(/* byte[] */ba){
- // summary
- // Encode an array of bytes or a string as a base64-encoded string
- if(typeof ba == "string"){
- ba = Array.prototype.map.call(ba, function(c){ return c.charCodeAt(0)});
- }
- var s=[], l=ba.length;
- var rm=l%3;
- var x=l-rm;
- for (var i=0; i<x;){
- var t=ba[i++]<<16|ba[i++]<<8|ba[i++];
- s.push(tab.charAt((t>>>18)&0x3f));
- s.push(tab.charAt((t>>>12)&0x3f));
- s.push(tab.charAt((t>>>6)&0x3f));
- s.push(tab.charAt(t&0x3f));
- }
- // deal with trailers, based on patch from Peter Wood.
- switch(rm){
- case 2:{
- var t=ba[i++]<<16|ba[i++]<<8;
- s.push(tab.charAt((t>>>18)&0x3f));
- s.push(tab.charAt((t>>>12)&0x3f));
- s.push(tab.charAt((t>>>6)&0x3f));
- s.push(p);
- break;
- }
- case 1:{
- var t=ba[i++]<<16;
- s.push(tab.charAt((t>>>18)&0x3f));
- s.push(tab.charAt((t>>>12)&0x3f));
- s.push(p);
- s.push(p);
- break;
- }
+/* Copyright (C) 1999 Masanao Izumo <iz@onicos.co.jp>
+ * Version: 1.0
+ * LastModified: Dec 25 1999
+ * This library is free. You can redistribute it and/or modify it.
+ */
+
+
+var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+var base64DecodeChars = new Array(
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
+ 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
+ -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
+ 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
+ -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
+ 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1);
+
+exports.encode = function(str) {
+ var out, i, len;
+ var c1, c2, c3;
+
+ len = str.length;
+ i = 0;
+ out = "";
+ while(i < len) {
+ c1 = str.charCodeAt(i++) & 0xff;
+ if(i == len)
+ {
+ out += base64EncodeChars.charAt(c1 >> 2);
+ out += base64EncodeChars.charAt((c1 & 0x3) << 4);
+ out += "==";
+ break;
}
- return s.join(""); // string
-};
-
-exports.decode=function(/* string */str){
- // summary
- // Convert a base64-encoded string to a string
- var s=str.split(""), out=[];
- var l=s.length;
- while(s[--l]==p){ } // strip off trailing padding
- for (var i=0; i<l;){
- var t=tab.indexOf(s[i++])<<18;
- if(i<=l){ t|=tab.indexOf(s[i++])<<12 };
- if(i<=l){ t|=tab.indexOf(s[i++])<<6 };
- if(i<=l){ t|=tab.indexOf(s[i++]) };
- out.push((t>>>16)&0xff);
- out.push((t>>>8)&0xff);
- out.push(t&0xff);
+ c2 = str.charCodeAt(i++);
+ if(i == len)
+ {
+ out += base64EncodeChars.charAt(c1 >> 2);
+ out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));
+ out += base64EncodeChars.charAt((c2 & 0xF) << 2);
+ out += "=";
+ break;
}
- // strip off any null bytes
- while(out[out.length-1]==0){ out.pop(); }
- return out.map(String.fromCharCode).join("");
-};
+ c3 = str.charCodeAt(i++);
+ out += base64EncodeChars.charAt(c1 >> 2);
+ out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));
+ out += base64EncodeChars.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6));
+ out += base64EncodeChars.charAt(c3 & 0x3F);
+ }
+ return out;
+}
+
+exports.decode = function(str) {
+ var c1, c2, c3, c4;
+ var i, len, out;
+
+ len = str.length;
+ i = 0;
+ out = "";
+ while(i < len) {
+ /* c1 */
+ do {
+ c1 = base64DecodeChars[str.charCodeAt(i++) & 0xff];
+ } while(i < len && c1 == -1);
+ if(c1 == -1)
+ break;
+
+ /* c2 */
+ do {
+ c2 = base64DecodeChars[str.charCodeAt(i++) & 0xff];
+ } while(i < len && c2 == -1);
+ if(c2 == -1)
+ break;
+
+ out += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4));
+
+ /* c3 */
+ do {
+ c3 = str.charCodeAt(i++) & 0xff;
+ if(c3 == 61)
+ return out;
+ c3 = base64DecodeChars[c3];
+ } while(i < len && c3 == -1);
+ if(c3 == -1)
+ break;
+
+ out += String.fromCharCode(((c2 & 0XF) << 4) | ((c3 & 0x3C) >> 2));
+
+ /* c4 */
+ do {
+ c4 = str.charCodeAt(i++) & 0xff;
+ if(c4 == 61)
+ return out;
+ c4 = base64DecodeChars[c4];
+ } while(i < len && c4 == -1);
+ if(c4 == -1)
+ break;
+ out += String.fromCharCode(((c3 & 0x03) << 6) | c4);
+ }
+ return out;
+}

0 comments on commit 190afc4

Please sign in to comment.