/*
* Copyright (C) 2010 Preston Lacey http://javaflacencoder.sourceforge.net/
* All Rights Reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
package eclipse.controller.util;
import java.io.PrintWriter;
import java.io.StringWriter;
import org.apache.log4j.Logger;
/**
* libFLAC - Free Lossless Audio Codec library
* Copyright (C) 2000,2001,2002,2003 Josh Coalson
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* Utility class to calculate 8-bit CRC.
* @author kc7bfi
*/
public final class CRC8 {
// CRC-8, poly = x^8 + x^2 + x^1 + x^0, init = 0
private static final byte[] CRC8_TABLE =
new byte[] {
(byte) 0x00, (byte) 0x5e, (byte) 0xbc, (byte) 0xe2, (byte) 0x61, (byte) 0x3f, (byte) 0xdd, (byte) 0x83,
(byte) 0xc2, (byte) 0x9c, (byte) 0x7e, (byte) 0x20, (byte) 0xa3, (byte) 0xfd, (byte) 0x1f, (byte) 0x41,
(byte) 0x9d, (byte) 0xc3, (byte) 0x21, (byte) 0x7f, (byte) 0xfc, (byte) 0xa2, (byte) 0x40, (byte) 0x1e,
(byte) 0x5f, (byte) 0x01, (byte) 0xe3, (byte) 0xbd, (byte) 0x3e, (byte) 0x60, (byte) 0x82, (byte) 0xdc,
(byte) 0x23, (byte) 0x7d, (byte) 0x9f, (byte) 0xc1, (byte) 0x42, (byte) 0x1c, (byte) 0xfe, (byte) 0xa0,
(byte) 0xe1, (byte) 0xbf, (byte) 0x5d, (byte) 0x03, (byte) 0x80, (byte) 0xde, (byte) 0x3c, (byte) 0x62,
(byte) 0xbe, (byte) 0xe0, (byte) 0x02, (byte) 0x5c, (byte) 0xdf, (byte) 0x81, (byte) 0x63, (byte) 0x3d,
(byte) 0x7c, (byte) 0x22, (byte) 0xc0, (byte) 0x9e, (byte) 0x1d, (byte) 0x43, (byte) 0xa1, (byte) 0xff,
(byte) 0x46, (byte) 0x18, (byte) 0xfa, (byte) 0xa4, (byte) 0x27, (byte) 0x79, (byte) 0x9b, (byte) 0xc5,
(byte) 0x84, (byte) 0xda, (byte) 0x38, (byte) 0x66, (byte) 0xe5, (byte) 0xbb, (byte) 0x59, (byte) 0x07,
(byte) 0xdb, (byte) 0x85, (byte) 0x67, (byte) 0x39, (byte) 0xba, (byte) 0xe4, (byte) 0x06, (byte) 0x58,
(byte) 0x19, (byte) 0x47, (byte) 0xa5, (byte) 0xfb, (byte) 0x78, (byte) 0x26, (byte) 0xc4, (byte) 0x9a,
(byte) 0x65, (byte) 0x3b, (byte) 0xd9, (byte) 0x87, (byte) 0x04, (byte) 0x5a, (byte) 0xb8, (byte) 0xe6,
(byte) 0xa7, (byte) 0xf9, (byte) 0x1b, (byte) 0x45, (byte) 0xc6, (byte) 0x98, (byte) 0x7a, (byte) 0x24,
(byte) 0xf8, (byte) 0xa6, (byte) 0x44, (byte) 0x1a, (byte) 0x99, (byte) 0xc7, (byte) 0x25, (byte) 0x7b,
(byte) 0x3a, (byte) 0x64, (byte) 0x86, (byte) 0xd8, (byte) 0x5b, (byte) 0x05, (byte) 0xe7, (byte) 0xb9,
(byte) 0x8c, (byte) 0xd2, (byte) 0x30, (byte) 0x6e, (byte) 0xed, (byte) 0xb3, (byte) 0x51, (byte) 0x0f,
(byte) 0x4e, (byte) 0x10, (byte) 0xf2, (byte) 0xac, (byte) 0x2f, (byte) 0x71, (byte) 0x93, (byte) 0xcd,
(byte) 0x11, (byte) 0x4f, (byte) 0xad, (byte) 0xf3, (byte) 0x70, (byte) 0x2e, (byte) 0xcc, (byte) 0x92,
(byte) 0xd3, (byte) 0x8d, (byte) 0x6f, (byte) 0x31, (byte) 0xb2, (byte) 0xec, (byte) 0x0e, (byte) 0x50,
(byte) 0xaf, (byte) 0xf1, (byte) 0x13, (byte) 0x4d, (byte) 0xce, (byte) 0x90, (byte) 0x72, (byte) 0x2c,
(byte) 0x6d, (byte) 0x33, (byte) 0xd1, (byte) 0x8f, (byte) 0x0c, (byte) 0x52, (byte) 0xb0, (byte) 0xee,
(byte) 0x32, (byte) 0x6c, (byte) 0x8e, (byte) 0xd0, (byte) 0x53, (byte) 0x0d, (byte) 0xef, (byte) 0xb1,
(byte) 0xf0, (byte) 0xae, (byte) 0x4c, (byte) 0x12, (byte) 0x91, (byte) 0xcf, (byte) 0x2d, (byte) 0x73,
(byte) 0xca, (byte) 0x94, (byte) 0x76, (byte) 0x28, (byte) 0xab, (byte) 0xf5, (byte) 0x17, (byte) 0x49,
(byte) 0x08, (byte) 0x56, (byte) 0xb4, (byte) 0xea, (byte) 0x69, (byte) 0x37, (byte) 0xd5, (byte) 0x8b,
(byte) 0x57, (byte) 0x09, (byte) 0xeb, (byte) 0xb5, (byte) 0x36, (byte) 0x68, (byte) 0x8a, (byte) 0xd4,
(byte) 0x95, (byte) 0xcb, (byte) 0x29, (byte) 0x77, (byte) 0xf4, (byte) 0xaa, (byte) 0x48, (byte) 0x16,
(byte) 0xe9, (byte) 0xb7, (byte) 0x55, (byte) 0x0b, (byte) 0x88, (byte) 0xd6, (byte) 0x34, (byte) 0x6a,
(byte) 0x2b, (byte) 0x75, (byte) 0x97, (byte) 0xc9, (byte) 0x4a, (byte) 0x14, (byte) 0xf6, (byte) 0xa8,
(byte) 0x74, (byte) 0x2a, (byte) 0xc8, (byte) 0x96, (byte) 0x15, (byte) 0x4b, (byte) 0xa9, (byte) 0xf7,
(byte) 0xb6, (byte) 0xe8, (byte) 0x0a, (byte) 0x54, (byte) 0xd7, (byte) 0x89, (byte) 0x6b, (byte) 0x35};
/**
* Update the CRC value with a byte data.
*
* @param data The byte data
* @param crc The starting CRC value
* @return The updated CRC value
*/
public static byte update(byte data, byte crc) {
return CRC8_TABLE[crc ^ data];
}
/**
* Update the CRC value with data from a byte array.
*
* @param data The byte array
* @param len The byte array length
* @param crc The starting CRC value
* @return The updated CRC value
*/
public static byte updateBlock(byte[] data, int len, byte crc) {
int tmp = 0;
for (int i = 0; i < len; i++){
byte[] bt = new byte[]{(byte) (crc ^ data[i])};
try {
tmp =(int) ByteManipulator.byteArrayToInt(bt,0,1,false,false);
} catch (Exception e) {
StringWriter stack = new StringWriter();
e.printStackTrace(new PrintWriter(stack));
Logger.getLogger("main").error("Caught exception; decorating with appropriate status template : " + stack.toString());
}
crc = CRC8_TABLE[tmp];
}
return crc;
}
/**
* Calculate the CRC value with data from a byte array.
*
* @param data The byte array
* @param len The byte array length
* @return The calculated CRC value
*/
public static byte calc(byte[] data, int len) {
byte crc = 0;
for (int i = 0; i < len; i++)
crc = CRC8_TABLE[(crc ^ data[i]) & 0xff];
return crc;
}
}