Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame^] | 1 | /* Get REL relocation information at given index. |
| 2 | Copyright (C) 2000, 2001, 2002 Red Hat, Inc. |
| 3 | Written by Ulrich Drepper <drepper@redhat.com>, 2000. |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation, version 2. |
| 8 | |
| 9 | This program is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | GNU General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU General Public License |
| 15 | along with this program; if not, write to the Free Software Foundation, |
| 16 | Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 17 | |
| 18 | #ifdef HAVE_CONFIG_H |
| 19 | # include <config.h> |
| 20 | #endif |
| 21 | |
| 22 | #include <gelf.h> |
| 23 | #include <string.h> |
| 24 | |
| 25 | #include "libelfP.h" |
| 26 | |
| 27 | |
| 28 | GElf_Rel * |
| 29 | gelf_getrel (data, ndx, dst) |
| 30 | Elf_Data *data; |
| 31 | int ndx; |
| 32 | GElf_Rel *dst; |
| 33 | { |
| 34 | Elf_Data_Scn *data_scn = (Elf_Data_Scn *) data; |
| 35 | Elf_Scn *scn; |
| 36 | GElf_Rel *result; |
| 37 | |
| 38 | if (data_scn == NULL) |
| 39 | return NULL; |
| 40 | |
| 41 | if (unlikely (ndx < 0)) |
| 42 | { |
| 43 | __libelf_seterrno (ELF_E_INVALID_INDEX); |
| 44 | return NULL; |
| 45 | } |
| 46 | |
| 47 | if (unlikely (data_scn->d.d_type != ELF_T_REL)) |
| 48 | { |
| 49 | __libelf_seterrno (ELF_E_INVALID_HANDLE); |
| 50 | return NULL; |
| 51 | } |
| 52 | |
| 53 | /* This is the one place where we have to take advantage of the fact |
| 54 | that an `Elf_Data' pointer is also a pointer to `Elf_Data_Scn'. |
| 55 | The interface is broken so that it requires this hack. */ |
| 56 | scn = data_scn->s; |
| 57 | |
| 58 | rwlock_rdlock (scn->elf->lock); |
| 59 | |
| 60 | if (scn->elf->class == ELFCLASS32) |
| 61 | { |
| 62 | /* We have to convert the data. */ |
| 63 | if (unlikely ((ndx + 1) * sizeof (Elf32_Rel) > data_scn->d.d_size)) |
| 64 | { |
| 65 | __libelf_seterrno (ELF_E_INVALID_INDEX); |
| 66 | result = NULL; |
| 67 | } |
| 68 | else |
| 69 | { |
| 70 | Elf32_Rel *src = &((Elf32_Rel *) data_scn->d.d_buf)[ndx]; |
| 71 | |
| 72 | dst->r_offset = src->r_offset; |
| 73 | dst->r_info = GELF_R_INFO (ELF32_R_SYM (src->r_info), |
| 74 | ELF32_R_TYPE (src->r_info)); |
| 75 | |
| 76 | result = dst; |
| 77 | } |
| 78 | } |
| 79 | else |
| 80 | { |
| 81 | /* Simply copy the data after we made sure we are actually getting |
| 82 | correct data. */ |
| 83 | if (unlikely ((ndx + 1) * sizeof (Elf64_Rel) > data_scn->d.d_size)) |
| 84 | { |
| 85 | __libelf_seterrno (ELF_E_INVALID_INDEX); |
| 86 | result = NULL; |
| 87 | } |
| 88 | else |
| 89 | result = memcpy (dst, &((Elf64_Rel *) data_scn->d.d_buf)[ndx], |
| 90 | sizeof (Elf64_Rel)); |
| 91 | } |
| 92 | |
| 93 | rwlock_unlock (scn->elf->lock); |
| 94 | |
| 95 | return result; |
| 96 | } |