Branch data Line data Source code
1 : : /* Get section at specific index.
2 : : Copyright (C) 2005, 2008, 2015 Red Hat, Inc.
3 : : This file is part of elfutils.
4 : : Contributed by Ulrich Drepper <drepper@redhat.com>, 2005.
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 <stddef.h>
36 : : #include <stdlib.h>
37 : :
38 : : #include "libelfP.h"
39 : :
40 : : #ifndef LIBELFBITS
41 : : # define LIBELFBITS 32
42 : : #endif
43 : :
44 : :
45 : : Elf_Scn *
46 : 488 : elfw2(LIBELFBITS,offscn) (Elf *elf, ElfW2(LIBELFBITS,Off) offset)
47 : : {
48 [ + - ]: 488 : if (elf == NULL)
49 : : return NULL;
50 : :
51 [ - + ]: 488 : if (unlikely (elf->kind != ELF_K_ELF))
52 : : {
53 : 0 : __libelf_seterrno (ELF_E_INVALID_HANDLE);
54 : 0 : return NULL;
55 : : }
56 : :
57 : 488 : Elf_ScnList *runp = &elf->state.ELFW(elf,LIBELFBITS).scns;
58 : :
59 : : /* If we have not looked at section headers before,
60 : : we might need to read them in first. */
61 [ + - ]: 488 : if (runp->cnt > 0
62 [ + + ]: 488 : && unlikely (runp->data[0].shdr.ELFW(e,LIBELFBITS) == NULL)
63 [ # # ][ + - ]: 1 : && unlikely (elfw2(LIBELFBITS,getshdr) (&runp->data[0]) == NULL))
64 : : return NULL;
65 : :
66 : 488 : rwlock_rdlock (elf->lock);
67 : :
68 : 488 : Elf_Scn *result = NULL;
69 : :
70 : : /* Find the section in the list. */
71 : 488 : while (1)
72 : : {
73 [ + + ]: 10302 : for (unsigned int i = 0; i < runp->cnt; ++i)
74 [ + + ]: 10292 : if (runp->data[i].shdr.ELFW(e,LIBELFBITS)->sh_offset == offset)
75 : : {
76 : 498 : result = &runp->data[i];
77 : :
78 : : /* If this section is empty, the following one has the same
79 : : sh_offset. We presume the caller is looking for a nonempty
80 : : section, so keep looking if this one is empty. */
81 [ + - ]: 498 : if (runp->data[i].shdr.ELFW(e,LIBELFBITS)->sh_size != 0
82 [ + + ]: 498 : && runp->data[i].shdr.ELFW(e,LIBELFBITS)->sh_type != SHT_NOBITS)
83 : 478 : goto out;
84 : : }
85 : :
86 : 10 : runp = runp->next;
87 [ - + ]: 10 : if (runp == NULL)
88 : : {
89 : 10 : __libelf_seterrno (ELF_E_INVALID_OFFSET);
90 : 10 : break;
91 : : }
92 : : }
93 : :
94 : : out:
95 : : rwlock_unlock (elf->lock);
96 : :
97 : : return result;
98 : : }
99 : : INTDEF(elfw2(LIBELFBITS,offscn))
|