mdw@git.distorted.org.uk Git - ssr/blob - StraySrc/SDLS/cdll/h/crc32

   1 /*
   2  * crc32.h
   3  *
   4  * Calculates 32-bit CRCs (Cyclic Redundancy Checks)
   5  *
   6  * © 1993-1998 Straylight
   7  */
   8
   9 /*----- Licensing note ----------------------------------------------------*
  10  *
  11  * This file is part of Straylight's Dynamic Linking System (SDLS)
  12  *
  13  * SDLS is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2, or (at your option)
  16  * any later version.
  17  *
  18  * SDLS is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with SDLS.  If not, write to the Free Software Foundation,
  25  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  26  */
  27
  28 #ifndef __crc32_h
  29 #define __crc32_h
  30
  31 #ifndef __stddef_h
  32   #include <stddef.h>
  33 #endif
  34
  35 /*
  36  * long crc32(long seed,void *data,size_t size,int diff)
  37  *
  38  * Use
  39  *  Calculates the CRC for a block of data.  The system has been designed to
  40  *  allow a CRC calculation to be carried out in stages, the result of
  41  *  previous calculations being used for continuation.
  42  *
  43  * Parameters
  44  *  long seed == 0 to start a calculation, or the result from the previous
  45  *    one to continue.
  46  *  void *data == pointer to the data to check
  47  *  size_t size == size (in bytes) of the data (just this block)
  48  *  int diff == the address difference between bytes to check (normally one,
  49  *    for all bytes).
  50  *
  51  * Returns
  52  *   The CRC for all the data checked so far.
  53  */
  54
  55 long crc32(long seed,void *data,size_t size,int diff);
  56
  57 #endif