1/* Get additional required symbol version information at the given offset.
2   Copyright (C) 1999, 2000, 2001, 2002 Red Hat, Inc.
3   Written by Ulrich Drepper <drepper@redhat.com>, 1999.
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 <assert.h>
23#include <gelf.h>
24#include <string.h>
25
26#include "libelfP.h"
27
28
29GElf_Vernaux *
30gelf_getvernaux (data, offset, dst)
31     Elf_Data *data;
32     int offset;
33     GElf_Vernaux *dst;
34{
35  GElf_Vernaux *result;
36
37  if (data == NULL)
38    return NULL;
39
40  if (unlikely (data->d_type != ELF_T_VNEED))
41    {
42      __libelf_seterrno (ELF_E_INVALID_HANDLE);
43      return NULL;
44    }
45
46  /* It's easy to handle this type.  It has the same size for 32 and
47     64 bit objects.  And fortunately the `ElfXXX_Vernaux' records
48     also have the same size.  */
49  assert (sizeof (GElf_Vernaux) == sizeof (Elf32_Verneed));
50  assert (sizeof (GElf_Vernaux) == sizeof (Elf64_Verneed));
51  assert (sizeof (GElf_Vernaux) == sizeof (Elf32_Vernaux));
52  assert (sizeof (GElf_Vernaux) == sizeof (Elf64_Vernaux));
53
54  rwlock_rdlock (((Elf_Data_Scn *) data)->s->elf->lock);
55
56  /* The data is already in the correct form.  Just make sure the
57     index is OK.  */
58  if (unlikely (offset < 0)
59      || unlikely (offset + sizeof (GElf_Vernaux) > data->d_size)
60      || unlikely (offset % sizeof (GElf_Vernaux) != 0))
61    {
62      __libelf_seterrno (ELF_E_OFFSET_RANGE);
63      result = NULL;
64    }
65  else
66    result = (GElf_Vernaux *) memcpy (dst, (char *) data->d_buf + offset,
67				      sizeof (GElf_Verneed));
68
69  rwlock_unlock (((Elf_Data_Scn *) data)->s->elf->lock);
70
71  return result;
72}
73