elf/simple-dl-hash.h

   1 /* __simple_dl_elf_hash for testing true elf symbol lookup.
   2    Copyright (C) 2022 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _SIMPLE_DL_ELF_HASH_H
  20 #define _SIMPLE_DL_ELF_HASH_H 1
  21
  22 #include <stdint.h>
  23
  24 /* For testing/benchmarking purposes.  Real implementation in
  25    sysdeps/generic/dl-hash.h.  */
  26 static uint32_t
  27 __attribute__ ((unused))
  28 __simple_dl_elf_hash (const char *name_arg)
  29 {
  30   unsigned long int hash = 0;
  31   for (unsigned char c = *name_arg; c != '\0'; c = *(++name_arg))
  32     {
  33       unsigned long int hi;
  34       hash = (hash << 4) + c;
  35       hi = hash & 0xf0000000;
  36       hash ^= hi >> 24;
  37       hash &= 0x0fffffff;
  38     }
  39   return hash;
  40 }
  41
  42 #endif /* simple-dl-hash.h */