/* Base64.java -- Base64 encoding and decoding.
Copyright (C) 2003 Casey Marshall <rsdio@metastatic.org>
This file is a part of Jessie.
Jessie is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
Jessie is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License along
with Jessie; if not, write to the
Free Software Foundation, Inc.,
59 Temple Place, Suite 330,
Boston, MA 02111-1307
USA
Linking this library statically or dynamically with other modules is
making a combined work based on this library. Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.
As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under terms
of your choice, provided that you also meet, for each linked independent
module, the terms and conditions of the license of that module. An
independent module is a module which is not derived from or based on
this library. If you modify this library, you may extend this exception
to your version of the library, but you are not obligated to do so. If
you do not wish to do so, delete this exception statement from your
version.
--
Base64 encoding derived from ISC's DHCP. Copyright notices from DHCP
follow. See http://www.isc.org/products/DHCP/.
Copyright (c) 1996 by Internet Software Consortium.
Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
--
Portions Copyright (c) 1995 by International Business Machines, Inc.
International Business Machines, Inc. (hereinafter called IBM) grants
permission under its copyrights to use, copy, modify, and distribute
this Software with or without fee, provided that the above copyright
notice and all paragraphs of this notice appear in all copies, and
that the name of IBM not be used in connection with the marketing of
any product incorporating the Software or modifications thereof,
without specific, written prior permission.
To the extent it has a right to do so, IBM grants an immunity from
suit under its patents, if any, for the use, sale or manufacture of
products to the extent that such products are used for performing
Domain Name System dynamic updates in TCP/IP networks by means of the
Software. No immunity is granted for any product per se or for any
other function of any product.
THE SOFTWARE IS PROVIDED "AS IS", AND IBM DISCLAIMS ALL WARRANTIES,
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE. IN NO EVENT SHALL IBM BE LIABLE FOR ANY SPECIAL,
DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
SOFTWARE, EVEN IF IBM IS APPRISED OF THE POSSIBILITY OF SUCH
DAMAGES. */
package org.geogebra.desktop.geogebra3D.input3D.leonar3do;
import java.io.IOException;
import org.geogebra.common.util.StringUtil;
import org.geogebra.common.util.debug.Log;
/**
* Encodes / decodes binary file (as array of bytes) to / from Base64 string
*
*/
public final class Base64 {
// No constructor.
private Base64() {
}
// Class methods.
// -------------------------------------------------------------------------
/** Base-64 characters. */
private static final String BASE_64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
/** Base-64 padding character. */
private static final char BASE_64_PAD = '=';
/**
* Base64 encode a byte array, returning the returning string.
*
* @param buf
* The byte array to encode.
* @param tw
* The total length of any line, 0 for unlimited.
* @return <tt>buf</tt> encoded in Base64.
*/
public static String encode(byte[] buf, int tw) {
int srcLength = buf.length;
byte[] input = new byte[3];
int[] output = new int[4];
StringBuilder out = new StringBuilder();
int i = 0;
int chars = 0;
while (srcLength > 2) {
input[0] = buf[i++];
input[1] = buf[i++];
input[2] = buf[i++];
srcLength -= 3;
output[0] = (input[0] & 0xff) >>> 2;
output[1] = ((input[0] & 0x03) << 4) + ((input[1] & 0xff) >>> 4);
output[2] = ((input[1] & 0x0f) << 2) + ((input[2] & 0xff) >>> 6);
output[3] = input[2] & 0x3f;
out.append(BASE_64.charAt(output[0]));
if (tw > 0 && ++chars % tw == 0) {
out.append("\n");
}
out.append(BASE_64.charAt(output[1]));
if (tw > 0 && ++chars % tw == 0) {
out.append("\n");
}
out.append(BASE_64.charAt(output[2]));
if (tw > 0 && ++chars % tw == 0) {
out.append("\n");
}
out.append(BASE_64.charAt(output[3]));
if (tw > 0 && ++chars % tw == 0) {
out.append("\n");
}
}
if (srcLength != 0) {
input[0] = input[1] = input[2] = 0;
for (int j = 0; j < srcLength; j++) {
input[j] = buf[i + j];
}
output[0] = (input[0] & 0xff) >>> 2;
output[1] = ((input[0] & 0x03) << 4) + ((input[1] & 0xff) >>> 4);
output[2] = ((input[1] & 0x0f) << 2) + ((input[2] & 0xff) >>> 6);
out.append(BASE_64.charAt(output[0]));
if (tw > 0 && ++chars % tw == 0) {
out.append("\n");
}
out.append(BASE_64.charAt(output[1]));
if (tw > 0 && ++chars % tw == 0) {
out.append("\n");
}
if (srcLength == 1) {
out.append(BASE_64_PAD);
} else {
out.append(BASE_64.charAt(output[2]));
}
if (tw > 0 && ++chars % tw == 0) {
out.append("\n");
}
out.append(BASE_64_PAD);
if (tw > 0 && ++chars % tw == 0) {
out.append("\n");
}
}
if (tw > 0) {
out.append("\n");
}
return out.toString();
}
/**
* Decode a Base-64 string into a byte array.
*
* @param b64
* The Base-64 encoded string.
* @return The decoded bytes.
* @throws java.io.IOException
* If the argument is not a valid Base-64 encoding.
*/
public static byte[] decode(String b64) throws IOException {
int state = 0, i, j = 0;
byte temp = 0;
// TODO b64.length()*3/4 should be sufficient
byte[] result = new byte[b64.length()];
for (i = 0; i < b64.length(); i++) {
if (StringUtil.isWhitespace(b64.charAt(i))) {
continue;
}
if (b64.charAt(i) == BASE_64_PAD) {
break;
}
int pos = BASE_64.indexOf(b64.charAt(i));
if (pos < 0) {
throw new IOException("non-Base64 character " + b64.charAt(i));
}
switch (state) {
case 0:
temp = (byte) (pos - BASE_64.indexOf('A') << 2);
state = 1;
break;
case 1:
temp |= (byte) (pos - BASE_64.indexOf('A') >>> 4);
result[j] = temp;
j++;
temp = (byte) ((pos - BASE_64.indexOf('A') & 0x0f) << 4);
state = 2;
break;
case 2:
temp |= (byte) ((pos - BASE_64.indexOf('A') & 0x7f) >>> 2);
result[j] = temp;
j++;
temp = (byte) ((pos - BASE_64.indexOf('A') & 0x03) << 6);
state = 3;
break;
case 3:
temp |= (byte) (pos - BASE_64.indexOf('A') & 0xff);
result[j] = temp;
j++;
state = 0;
break;
default:
throw new Error("this statement should be unreachable");
}
}
if (i < b64.length() && b64.charAt(i) == BASE_64_PAD) {
switch (state) {
case 0:
case 1:
throw new IOException("malformed Base64 sequence");
case 2:
for (; i < b64.length(); i++) {
if (!StringUtil.isWhitespace(b64.charAt(i))) {
break;
}
}
// We must see a second pad character here.
if (b64.charAt(i) != BASE_64_PAD) {
throw new IOException("malformed Base64 sequence");
}
i++;
//$FALL-THROUGH$
case 3:
i++;
for (; i < b64.length(); i++) {
// We should only see whitespace after this.
if (!StringUtil.isWhitespace(b64.charAt(i))) {
Log.error("" + b64.charAt(i));
throw new IOException("malformed Base64 sequence");
}
}
}
} else {
if (state != 0) {
throw new IOException("malformed Base64 sequence");
}
}
return result;
}
}