1 /* Get symbol version information at the given index.
2 Copyright (C) 1999, 2000, 2001, 2002, 2005, 2009, 2014, 2015 Red Hat, Inc.
3 This file is part of elfutils.
4 Written by Ulrich Drepper <drepper@redhat.com>, 1999.
5
6 This file is free software; you can redistribute it and/or modify
7 it under the terms of either
8
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
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
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/>. */
29
30 #ifdef HAVE_CONFIG_H
31 # include <config.h>
32 #endif
33
34 #include <assert.h>
35 #include <gelf.h>
36 #include <string.h>
37
38 #include "libelfP.h"
39
40
41 GElf_Versym *
gelf_getversym(Elf_Data * data,int ndx,GElf_Versym * dst)42 gelf_getversym (Elf_Data *data, int ndx, GElf_Versym *dst)
43 {
44 Elf_Data_Scn *data_scn = (Elf_Data_Scn *) data;
45 Elf_Scn *scn;
46 GElf_Versym *result;
47
48 if (data == NULL)
49 return NULL;
50
51 if (unlikely (data->d_type != ELF_T_HALF))
52 {
53 __libelf_seterrno (ELF_E_INVALID_HANDLE);
54 return NULL;
55 }
56
57 /* This is the one place where we have to take advantage of the fact
58 that an `Elf_Data' pointer is also a pointer to `Elf_Data_Scn'.
59 The interface is broken so that it requires this hack. */
60 scn = data_scn->s;
61
62 /* It's easy to handle this type. It has the same size for 32 and
63 64 bit objects. */
64 assert (sizeof (GElf_Versym) == sizeof (Elf32_Versym));
65 assert (sizeof (GElf_Versym) == sizeof (Elf64_Versym));
66
67 rwlock_rdlock (scn->elf->lock);
68
69 /* The data is already in the correct form. Just make sure the
70 index is OK. */
71 if (INVALID_NDX (ndx, GElf_Versym, data))
72 {
73 __libelf_seterrno (ELF_E_INVALID_INDEX);
74 result = NULL;
75 }
76 else
77 {
78 *dst = ((GElf_Versym *) data->d_buf)[ndx];
79
80 result = dst;
81 }
82
83 rwlock_unlock (scn->elf->lock);
84
85 return result;
86 }
87