diff options
Diffstat (limited to 'elf/dl-hash.h')
| -rw-r--r-- | elf/dl-hash.h | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/elf/dl-hash.h b/elf/dl-hash.h new file mode 100644 index 0000000000..007f192a23 --- /dev/null +++ b/elf/dl-hash.h @@ -0,0 +1,69 @@ +/* Compute hash alue for given string according to ELF standard. + Copyright (C) 1995, 1996, 1997 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 Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. 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 now overflow is possible so we optimized it a + bit. */ +static inline unsigned +_dl_elf_hash (const char *name) +{ + unsigned long int hash = 0; + 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++; + if (*name != '\0') + { + hash = (hash << 4) + *name++; + while (*name != '\0') + { + unsigned long int hi; + hash = (hash << 4) + *name++; + hi = hash & 0xf0000000; + if (hi != 0) + { + hash ^= hi >> 24; + /* The ELF ABI says `hash &= ~hi', but + this is equivalent in this case and + on some machines one insn instead of + two. */ + hash ^= hi; + } + } + } + } + } + } + } + return hash; +} + +#endif /* dl-hash.h */ |