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/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.

   This program 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; version 2 of the License.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */


#include <my_global.h>
#include <my_sys.h>
#include <zlib.h>

/*
  Calculate a long checksum for a memoryblock.

  SYNOPSIS
    my_checksum()
      crc       start value for crc
      pos       pointer to memory block
      length    length of the block
*/

ha_checksum my_checksum(ha_checksum crc, const uchar *pos, size_t length)
{
#ifdef HAVE_CRC32_VPMSUM
  extern unsigned int crc32ieee_vpmsum(unsigned int crc, const unsigned char *p,
                                    unsigned long len);
  crc= (ha_checksum) crc32ieee_vpmsum((uint) crc, pos, (uint) length);
#else
  crc= (ha_checksum) crc32((uint)crc, pos, (uint) length);
#endif
  DBUG_PRINT("info", ("crc: %lu", (ulong) crc));
  return crc;
}