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Posted to commits@xerces.apache.org by je...@locus.apache.org on 2000/08/02 18:36:20 UTC

cvs commit: xml-xerces/java/src/org/apache/xerces/utils Base64.java

jeffreyr    00/08/02 09:36:20

  Modified:    java/src/org/apache/xerces/utils Base64.java
  Log:
  previous version only supported '7bit' encoding, so I added '8bit' encoding and
  fixed problem reported on Xerces-j mailiing list about out of boundaries array
  access.
  Also give code and decode static access.
  
  Revision  Changes    Path
  1.4       +44 -14    xml-xerces/java/src/org/apache/xerces/utils/Base64.java
  
  Index: Base64.java
  ===================================================================
  RCS file: /home/cvs/xml-xerces/java/src/org/apache/xerces/utils/Base64.java,v
  retrieving revision 1.3
  retrieving revision 1.4
  diff -u -r1.3 -r1.4
  --- Base64.java	2000/06/02 05:25:14	1.3
  +++ Base64.java	2000/08/02 16:36:20	1.4
  @@ -69,23 +69,24 @@
    * This class is used by XML Schema binary format validation
    *
    * @author Jeffrey Rodriguez
  - * @version     $Id: Base64.java,v 1.3 2000/06/02 05:25:14 jeffreyr Exp $
  + * @version     $Id: Base64.java,v 1.4 2000/08/02 16:36:20 jeffreyr Exp $
    */
   
   public final class  Base64 {
       static private final int  BASELENGTH         = 255;       
  -    static private final int  LOOKUPLENGTH       = 63;
  +    static private final int  LOOKUPLENGTH       = 64;
       static private final int  TWENTYFOURBITGROUP = 24;
       static private final int  EIGHTBIT           = 8;
       static private final int  SIXTEENBIT         = 16;
       static private final int  SIXBIT             = 6;
       static private final int  FOURBYTE           = 4;
  -
  -
  -    static private final byte PAD               = ( byte ) '=';
  +    static private final int  SIGN               = -128;
  +    static private final byte PAD                = ( byte ) '=';
  +    static private final boolean fDebug          = false;
       static private byte [] base64Alphabet       = new byte[BASELENGTH]; 
       static private byte [] lookUpBase64Alphabet = new byte[LOOKUPLENGTH];
   
  +
       static {
   
           for (int i = 0; i<BASELENGTH; i++ ) {
  @@ -105,7 +106,7 @@
           base64Alphabet['+']  = 62; 
           base64Alphabet['/']  = 63;
   
  -       for (int i = 0; i<=25; i++ )
  +        for (int i = 0; i<=25; i++ )
               lookUpBase64Alphabet[i] = (byte) ('A'+i );
   
           for (int i = 26,  j = 0; i<=51; i++, j++ )
  @@ -113,6 +114,8 @@
   
           for (int i = 52,  j = 0; i<=61; i++, j++ )
               lookUpBase64Alphabet[i] = (byte) ('0' + j );
  +        lookUpBase64Alphabet[62] = (byte) '+';
  +        lookUpBase64Alphabet[63] = (byte) '/';
   
       }
   
  @@ -144,7 +147,7 @@
        * @param binaryData Array containing binaryData
        * @return Encoded Base64 array
        */
  -    public byte[] encode( byte[] binaryData ) {
  +    public static byte[] encode( byte[] binaryData ) {
           int      lengthDataBits    = binaryData.length*EIGHTBIT;
           int      fewerThan24bits   = lengthDataBits%TWENTYFOURBITGROUP; 
           int      numberTriplets    = lengthDataBits/TWENTYFOURBITGROUP;
  @@ -161,6 +164,9 @@
           int encodedIndex = 0;
           int dataIndex   = 0;
           int i           = 0;
  +        if (fDebug ) {
  +            System.out.println("number of triplets = " + numberTriplets );
  +        }
           for ( i = 0; i<numberTriplets; i++ ) {
   
               dataIndex = i*3;
  @@ -168,13 +174,28 @@
               b2 = binaryData[dataIndex + 1];
               b3 = binaryData[dataIndex + 2];
   
  +            if (fDebug) {
  +                System.out.println( "b1= " + b1 +", b2= " + b2 + ", b3= " + b3 );
  +            }
  +
               l  = (byte)(b2 & 0x0f);
               k  = (byte)(b1 & 0x03);
   
               encodedIndex = i*4;
  -            encodedData[encodedIndex]   = lookUpBase64Alphabet[ b1 >>2 ]; 
  -            encodedData[encodedIndex+1] = lookUpBase64Alphabet[(b2 >>4 ) | ( k<<4 )];
  -            encodedData[encodedIndex+2] = lookUpBase64Alphabet[ (l <<2 ) | ( b3>>6)]; 
  +            byte val1 = ((b1 & SIGN)==0)?(byte)(b1>>2):(byte)((b1)>>2^0xc0);
  +
  +            byte val2 = ((b2 & SIGN)==0)?(byte)(b2>>4):(byte)((b2)>>4^0xf0); 
  +            byte val3 = ((b3 & SIGN)==0)?(byte)(b3>>6):(byte)((b3)>>6^0xfc);
  +
  +            encodedData[encodedIndex]   = lookUpBase64Alphabet[ val1 ]; 
  +            if (fDebug) {
  +                System.out.println( "val2 = " + val2 );
  +                System.out.println( "k4   = " + (k<<4));
  +                System.out.println( "vak  = " + (val2 | (k<<4)));
  +            }
  +
  +            encodedData[encodedIndex+1] = lookUpBase64Alphabet[ val2 | ( k<<4 )];
  +            encodedData[encodedIndex+2] = lookUpBase64Alphabet[ (l <<2 ) | val3 ]; 
               encodedData[encodedIndex+3] = lookUpBase64Alphabet[ b3 & 0x3f ];
           }
   
  @@ -184,7 +205,12 @@
           if (fewerThan24bits == EIGHTBIT ) {
               b1 = binaryData[dataIndex];
               k = (byte) ( b1 &0x03 );
  -            encodedData[encodedIndex]     = lookUpBase64Alphabet[ b1 >>2 ];
  +            if (fDebug ) {
  +                System.out.println("b1=" + b1);
  +                System.out.println("b1<<2 = " + (b1>>2) );
  +            }
  +            byte val1 = ((b1 & SIGN)==0)?(byte)(b1>>2):(byte)((b1)>>2^0xc0);
  +            encodedData[encodedIndex]     = lookUpBase64Alphabet[ val1 ];
               encodedData[encodedIndex + 1] = lookUpBase64Alphabet[ k<<4 ]; 
               encodedData[encodedIndex + 2] = PAD;
               encodedData[encodedIndex + 3] = PAD;
  @@ -194,8 +220,12 @@
               b2 = binaryData[dataIndex +1 ];
               l = ( byte ) ( b2 &0x0f );
               k = ( byte ) ( b1 &0x03 );
  -            encodedData[encodedIndex]     = lookUpBase64Alphabet[ b1 >>2 ];
  -            encodedData[encodedIndex + 1] = lookUpBase64Alphabet[ (b2 >>4 ) | ( k<<4 )];
  +
  +            byte val1 = ((b1 & SIGN)==0)?(byte)(b1>>2):(byte)((b1)>>2^0xc0);
  +            byte val2 = ((b2 & SIGN)==0)?(byte)(b2>>4):(byte)((b2)>>4^0xf0); 
  +
  +            encodedData[encodedIndex]     = lookUpBase64Alphabet[ val1 ];
  +            encodedData[encodedIndex + 1] = lookUpBase64Alphabet[ val2 | ( k<<4 )];
               encodedData[encodedIndex + 2] = lookUpBase64Alphabet[ l<<2 ]; 
               encodedData[encodedIndex + 3] = PAD;
           }
  @@ -209,7 +239,7 @@
        * @param binaryData Byte array containing Base64 data
        * @return Array containind decoded data.
        */
  -    public byte[] decode( byte[] base64Data ) {
  +    public static byte[] decode( byte[] base64Data ) {
           int      numberQuadruple    = base64Data.length/FOURBYTE;
           byte     decodedData[]      = null;
           byte     b1=0,b2=0,b3=0, b4=0, marker0=0, marker1=0;