Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 1 | /* Get REL relocation information at given index. |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 2 | Copyright (C) 2000, 2001, 2002, 2005, 2009, 2014 Red Hat, Inc. |
| 3 | This file is part of elfutils. |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 4 | Written by Ulrich Drepper <drepper@redhat.com>, 2000. |
| 5 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 6 | This file is free software; you can redistribute it and/or modify |
| 7 | it under the terms of either |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 8 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 9 | * the GNU Lesser General Public License as published by the Free |
| 10 | Software Foundation; either version 3 of the License, or (at |
| 11 | your option) any later version |
| 12 | |
| 13 | or |
| 14 | |
| 15 | * the GNU General Public License as published by the Free |
| 16 | Software Foundation; either version 2 of the License, or (at |
| 17 | your option) any later version |
| 18 | |
| 19 | or both in parallel, as here. |
| 20 | |
| 21 | elfutils is distributed in the hope that it will be useful, but |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 22 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 23 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 24 | General Public License for more details. |
| 25 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 26 | You should have received copies of the GNU General Public License and |
| 27 | the GNU Lesser General Public License along with this program. If |
| 28 | not, see <http://www.gnu.org/licenses/>. */ |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 29 | |
| 30 | #ifdef HAVE_CONFIG_H |
| 31 | # include <config.h> |
| 32 | #endif |
| 33 | |
| 34 | #include <gelf.h> |
| 35 | #include <string.h> |
| 36 | |
| 37 | #include "libelfP.h" |
| 38 | |
| 39 | |
| 40 | GElf_Rel * |
| 41 | gelf_getrel (data, ndx, dst) |
| 42 | Elf_Data *data; |
| 43 | int ndx; |
| 44 | GElf_Rel *dst; |
| 45 | { |
| 46 | Elf_Data_Scn *data_scn = (Elf_Data_Scn *) data; |
| 47 | Elf_Scn *scn; |
| 48 | GElf_Rel *result; |
| 49 | |
| 50 | if (data_scn == NULL) |
| 51 | return NULL; |
| 52 | |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 53 | if (unlikely (data_scn->d.d_type != ELF_T_REL)) |
| 54 | { |
| 55 | __libelf_seterrno (ELF_E_INVALID_HANDLE); |
| 56 | return NULL; |
| 57 | } |
| 58 | |
| 59 | /* This is the one place where we have to take advantage of the fact |
| 60 | that an `Elf_Data' pointer is also a pointer to `Elf_Data_Scn'. |
| 61 | The interface is broken so that it requires this hack. */ |
| 62 | scn = data_scn->s; |
| 63 | |
| 64 | rwlock_rdlock (scn->elf->lock); |
| 65 | |
| 66 | if (scn->elf->class == ELFCLASS32) |
| 67 | { |
| 68 | /* We have to convert the data. */ |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 69 | if (INVALID_NDX (ndx, Elf32_Rel, &data_scn->d)) |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 70 | { |
| 71 | __libelf_seterrno (ELF_E_INVALID_INDEX); |
| 72 | result = NULL; |
| 73 | } |
| 74 | else |
| 75 | { |
| 76 | Elf32_Rel *src = &((Elf32_Rel *) data_scn->d.d_buf)[ndx]; |
| 77 | |
| 78 | dst->r_offset = src->r_offset; |
| 79 | dst->r_info = GELF_R_INFO (ELF32_R_SYM (src->r_info), |
| 80 | ELF32_R_TYPE (src->r_info)); |
| 81 | |
| 82 | result = dst; |
| 83 | } |
| 84 | } |
| 85 | else |
| 86 | { |
| 87 | /* Simply copy the data after we made sure we are actually getting |
| 88 | correct data. */ |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 89 | if (INVALID_NDX (ndx, Elf64_Rel, &data_scn->d)) |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 90 | { |
| 91 | __libelf_seterrno (ELF_E_INVALID_INDEX); |
| 92 | result = NULL; |
| 93 | } |
| 94 | else |
| 95 | result = memcpy (dst, &((Elf64_Rel *) data_scn->d.d_buf)[ndx], |
| 96 | sizeof (Elf64_Rel)); |
| 97 | } |
| 98 | |
| 99 | rwlock_unlock (scn->elf->lock); |
| 100 | |
| 101 | return result; |
| 102 | } |