| 1 | /* Cache the location of a link map hash table. |
|---|---|
| 2 | Copyright (C) 1995-2022 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 | #include <assert.h> |
| 20 | #include <link.h> |
| 21 | #include <ldsodefs.h> |
| 22 | |
| 23 | void |
| 24 | _dl_setup_hash (struct link_map *map) |
| 25 | { |
| 26 | Elf_Symndx *hash; |
| 27 | |
| 28 | if (__glibc_likely (map->l_info[ELF_MACHINE_GNU_HASH_ADDRIDX] != NULL)) |
| 29 | { |
| 30 | Elf32_Word *hash32 |
| 31 | = (void *) D_PTR (map, l_info[ELF_MACHINE_GNU_HASH_ADDRIDX]); |
| 32 | map->l_nbuckets = *hash32++; |
| 33 | Elf32_Word symbias = *hash32++; |
| 34 | Elf32_Word bitmask_nwords = *hash32++; |
| 35 | /* Must be a power of two. */ |
| 36 | assert ((bitmask_nwords & (bitmask_nwords - 1)) == 0); |
| 37 | map->l_gnu_bitmask_idxbits = bitmask_nwords - 1; |
| 38 | map->l_gnu_shift = *hash32++; |
| 39 | |
| 40 | map->l_gnu_bitmask = (ElfW(Addr) *) hash32; |
| 41 | hash32 += __ELF_NATIVE_CLASS / 32 * bitmask_nwords; |
| 42 | |
| 43 | map->l_gnu_buckets = hash32; |
| 44 | hash32 += map->l_nbuckets; |
| 45 | map->l_gnu_chain_zero = hash32 - symbias; |
| 46 | |
| 47 | /* Initialize MIPS xhash translation table. */ |
| 48 | ELF_MACHINE_XHASH_SETUP (hash32, symbias, map); |
| 49 | |
| 50 | return; |
| 51 | } |
| 52 | |
| 53 | if (!map->l_info[DT_HASH]) |
| 54 | return; |
| 55 | hash = (void *) D_PTR (map, l_info[DT_HASH]); |
| 56 | |
| 57 | map->l_nbuckets = *hash++; |
| 58 | /* Skip nchain. */ |
| 59 | hash++; |
| 60 | map->l_buckets = hash; |
| 61 | hash += map->l_nbuckets; |
| 62 | map->l_chain = hash; |
| 63 | } |
| 64 |