root/trunk/txlib/txcrc32.c

//
//                     TxWin, Textmode Windowing Library
//
//   Original code Copyright (c) 1995-2005 Fsys Software and Jan van Wijk
//
// ==========================================================================
//
// This file contains Original Code and/or Modifications of Original Code as
// defined in and that are subject to the GNU Lesser General Public License.
// You may not use this file except in compliance with the License.
// BY USING THIS FILE YOU AGREE TO ALL TERMS AND CONDITIONS OF THE LICENSE.
// A copy of the License is provided with the Original Code and Modifications,
// and is also available at http://www.dfsee.com/txwin/lgpl.htm
//
// 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; (lgpl.htm) if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
// Questions on TxWin licensing can be directed to: txwin@fsys.nl
//
// ==========================================================================
//
// CRC32 implementation, using lookup-table; derived from textbook:
//       'C' programmers guide to NETBIOS
//
//       Plus HPFS superblock/spareblock checksum compatible one
//
// Author: J. van Wijk
//

#include <txlib.h>                              // TxLib interface


/* generated CRC32 table file; JvW 10-03-96*/
static ULONG crc32Table[] =
{
   0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
   0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
   0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
   0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
   0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
   0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
   0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
   0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
   0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
   0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
   0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
   0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
   0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
   0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
   0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
   0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
   0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
   0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
   0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
   0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
   0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
   0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
   0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
   0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
   0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
   0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
   0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
   0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
   0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
   0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
   0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
   0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
   0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
   0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
   0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
   0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
   0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
   0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
   0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
   0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
   0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
   0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
   0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
   0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
   0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
   0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
   0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
   0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
   0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
   0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
   0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
   0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
   0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
   0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
   0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
   0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
   0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
   0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
   0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
   0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
   0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
   0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
   0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
   0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};

/*****************************************************************************/
// Calculate CRC-32 value for supplied data
/*****************************************************************************/
ULONG TxCrc32
(
   void               *pcDat,                   // IN    pointer to data
   ULONG               ulSize                   // IN    length of data
)
{
   ULONG               crc = 0xffffffffL;       // preconditioning value
   ULONG               di;                      // data  index
   ULONG               ti;                      // table index
   char               *s;

   ENTER();
   TRACES(( "Data:%8.8lx length %8.8lx = %lu bytes\n", pcDat, ulSize, ulSize));

   for (di = 0,     s = (char *) pcDat;
        di < ulSize;
        di++,       s++)
   {
      ti  = ((crc ^ *s) & 0x000000ffL);
      crc = ((crc >> 8) & 0x00ffffffL) ^ crc32Table[ ti];
   }
   RETURN(~crc);                                // one's complement
}                                               // end 'TxCrc32'
/*---------------------------------------------------------------------------*/

#if defined (TESTMAIN)

#define CRC32_RESIDU     0xdebb20e3L

char  TestArray1[] = {'T', 'e', 's', 't'};      // crc32 = 78.4d.d1.32

char  TestArray2[] = {'T', 'e', 's', 't', 0x32, 0xd1, 0x4d, 0x78};

int main (int argc, char *argv[]);

int main (int argc, char *argv[])
{
   ULONG               crc1 = TxCrc32( TestArray1, sizeof(TestArray1));
   ULONG               crc2 = TxCrc32( TestArray2, sizeof(TestArray2));

   if (argc > 1)
   {
      crc1 = TxCrc32( argv[1], strlen(argv[1]));
      TxPrint("\n  Calculated crc32 value: %8.8lX\n",  crc1);
   }
   else
   {
      TxPrint("\n  crc1: %8.8lX\n",  crc1);
      TxPrint("\n  crc2: %8.8lX\n",  crc2);
      TxPrint("\n ~crc2: %8.8lX\n", ~crc2);

      TxPrint("\n ~crc2: %8.8lX\n", ~crc2);

      if (~crc2 == CRC32_RESIDU)
      {
         TxPrint("\nCRC32 algorithm/table is correct\n");
      }
      else
      {
         TxPrint("\nCRC32 algorithm/table is NOT correct!\n");
      }
   }
   return(0);
}
/*---------------------------------------------------------------------------*/
#endif


/*****************************************************************************/
// Calculate sector checksum, using HPFS algorithm
/*****************************************************************************/
ULONG TxHpfsCheckSum                            // RET   HPFS style crc
(
   char               *data                     // IN    data sector
)
{
   ULONG               cs = 0;                  // checksum value
   ULONG               i;                       // checksum value

   for (i = 0; i < SECTORSIZE; i++)
   {
      cs += (ULONG) *data++;
      cs  = (cs << 7) + (cs >> (25));
   }
   return( cs);
}                                               // end 'TxHpfsCheckSum'
/*---------------------------------------------------------------------------*/