Create jquery.base64.js

Author: kayalshri

jquery.base64.js

@@ -0,0 +1,190 @@
+/*jslint adsafe: false, bitwise: true, browser: true, cap: false, css: false,
+  debug: false, devel: true, eqeqeq: true, es5: false, evil: false,
+  forin: false, fragment: false, immed: true, laxbreak: false, newcap: true,
+  nomen: false, on: false, onevar: true, passfail: false, plusplus: true,
+  regexp: false, rhino: true, safe: false, strict: false, sub: false,
+  undef: true, white: false, widget: false, windows: false */
+/*global jQuery: false, window: false */
+//"use strict";
+
+/*
+ * Original code (c) 2010 Nick Galbreath
+ * http://code.google.com/p/stringencoders/source/browse/#svn/trunk/javascript
+ *
+ * jQuery port (c) 2010 Carlo Zottmann
+ * http://github.com/carlo/jquery-base64
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+/* base64 encode/decode compatible with window.btoa/atob
+ *
+ * window.atob/btoa is a Firefox extension to convert binary data (the "b")
+ * to base64 (ascii, the "a").
+ *
+ * It is also found in Safari and Chrome.  It is not available in IE.
+ *
+ * if (!window.btoa) window.btoa = $.base64.encode
+ * if (!window.atob) window.atob = $.base64.decode
+ *
+ * The original spec's for atob/btoa are a bit lacking
+ * https://developer.mozilla.org/en/DOM/window.atob
+ * https://developer.mozilla.org/en/DOM/window.btoa
+ *
+ * window.btoa and $.base64.encode takes a string where charCodeAt is [0,255]
+ * If any character is not [0,255], then an exception is thrown.
+ *
+ * window.atob and $.base64.decode take a base64-encoded string
+ * If the input length is not a multiple of 4, or contains invalid characters
+ *   then an exception is thrown.
+ */
+ 
+jQuery.base64 = ( function( $ ) {
+  
+  var _PADCHAR = "=",
+    _ALPHA = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/",
+    _VERSION = "1.0";
+
+
+  function _getbyte64( s, i ) {
+    // This is oddly fast, except on Chrome/V8.
+    // Minimal or no improvement in performance by using a
+    // object with properties mapping chars to value (eg. 'A': 0)
+
+    var idx = _ALPHA.indexOf( s.charAt( i ) );
+
+    if ( idx === -1 ) {
+      throw "Cannot decode base64";
+    }
+
+    return idx;
+  }
+  
+  
+  function _decode( s ) {
+    var pads = 0,
+      i,
+      b10,
+      imax = s.length,
+      x = [];
+
+    s = String( s );
+    
+    if ( imax === 0 ) {
+      return s;
+    }
+
+    if ( imax % 4 !== 0 ) {
+      throw "Cannot decode base64";
+    }
+
+    if ( s.charAt( imax - 1 ) === _PADCHAR ) {
+      pads = 1;
+
+      if ( s.charAt( imax - 2 ) === _PADCHAR ) {
+        pads = 2;
+      }
+
+      // either way, we want to ignore this last block
+      imax -= 4;
+    }
+
+    for ( i = 0; i < imax; i += 4 ) {
+      b10 = ( _getbyte64( s, i ) << 18 ) | ( _getbyte64( s, i + 1 ) << 12 ) | ( _getbyte64( s, i + 2 ) << 6 ) | _getbyte64( s, i + 3 );
+      x.push( String.fromCharCode( b10 >> 16, ( b10 >> 8 ) & 0xff, b10 & 0xff ) );
+    }
+
+    switch ( pads ) {
+      case 1:
+        b10 = ( _getbyte64( s, i ) << 18 ) | ( _getbyte64( s, i + 1 ) << 12 ) | ( _getbyte64( s, i + 2 ) << 6 );
+        x.push( String.fromCharCode( b10 >> 16, ( b10 >> 8 ) & 0xff ) );
+        break;
+
+      case 2:
+        b10 = ( _getbyte64( s, i ) << 18) | ( _getbyte64( s, i + 1 ) << 12 );
+        x.push( String.fromCharCode( b10 >> 16 ) );
+        break;
+    }
+
+    return x.join( "" );
+  }
+  
+  
+  function _getbyte( s, i ) {
+    var x = s.charCodeAt( i );
+
+    if ( x > 255 ) {
+      throw "INVALID_CHARACTER_ERR: DOM Exception 5";
+    }
+    
+    return x;
+  }
+
+
+  function _encode( s ) {
+    if ( arguments.length !== 1 ) {
+      throw "SyntaxError: exactly one argument required";
+    }
+
+    s = String( s );
+
+    var i,
+      b10,
+      x = [],
+      imax = s.length - s.length % 3;
+
+    if ( s.length === 0 ) {
+      return s;
+    }
+
+    for ( i = 0; i < imax; i += 3 ) {
+      b10 = ( _getbyte( s, i ) << 16 ) | ( _getbyte( s, i + 1 ) << 8 ) | _getbyte( s, i + 2 );
+      x.push( _ALPHA.charAt( b10 >> 18 ) );
+      x.push( _ALPHA.charAt( ( b10 >> 12 ) & 0x3F ) );
+      x.push( _ALPHA.charAt( ( b10 >> 6 ) & 0x3f ) );
+      x.push( _ALPHA.charAt( b10 & 0x3f ) );
+    }
+
+    switch ( s.length - imax ) {
+      case 1:
+        b10 = _getbyte( s, i ) << 16;
+        x.push( _ALPHA.charAt( b10 >> 18 ) + _ALPHA.charAt( ( b10 >> 12 ) & 0x3F ) + _PADCHAR + _PADCHAR );
+        break;
+
+      case 2:
+        b10 = ( _getbyte( s, i ) << 16 ) | ( _getbyte( s, i + 1 ) << 8 );
+        x.push( _ALPHA.charAt( b10 >> 18 ) + _ALPHA.charAt( ( b10 >> 12 ) & 0x3F ) + _ALPHA.charAt( ( b10 >> 6 ) & 0x3f ) + _PADCHAR );
+        break;
+    }
+
+    return x.join( "" );
+  }
+
+
+  return {
+    decode: _decode,
+    encode: _encode,
+    VERSION: _VERSION
+  };
+      
+}( jQuery ) );
+