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/* Compute hash value for given string according to ELF standard.

   Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C 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.

   The GNU C 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 the GNU C Library; if not, write to the Free

   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA

   02111-1307 USA.  */

#ifndef _DL_HASH_H

#define _DL_HASH_H      1

/* This is the hashing function specified by the ELF ABI.  In the

   first five operations no overflow is possible so we optimized it a

   bit.  */

static inline unsigned int

_dl_elf_hash (const unsigned char *name)

{

  unsigned long int hash = 0;

  if (*name != '\0')

    {

      hash = *name++;

      if (*name != '\0')

        {

          hash = (hash << 4) + *name++;

          if (*name != '\0')

            {

              hash = (hash << 4) + *name++;

              if (*name != '\0')

                {

                  hash = (hash << 4) + *name++;

                  if (*name != '\0')

                    {

                      hash = (hash << 4) + *name++;

                      while (*name != '\0')

                        {

                          unsigned long int hi;

                          hash = (hash << 4) + *name++;

                          hi = hash & 0xf0000000;

                          /* The algorithm specified in the ELF ABI is as

                             follows:

                             if (hi != 0)

                               hash ^= hi >> 24;

                             hash &= ~hi;

                             But the following is equivalent and a lot

                             faster, especially on modern processors.  */

                          hash ^= hi;

                          hash ^= hi >> 24;

                        }

                    }

                }

            }

        }

    }

  return hash;

}

#endif /* dl-hash.h */