1 /* Test program for elf_strptr function.
2 Copyright (C) 2015 Red Hat, Inc.
3 This file is part of elfutils.
4
5 This file 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; either version 3 of the License, or
8 (at your option) any later version.
9
10 elfutils is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
17
18 #ifdef HAVE_CONFIG_H
19 # include <config.h>
20 #endif
21
22 #include <errno.h>
23 #include <fcntl.h>
24 #include <inttypes.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <unistd.h>
29
30 #include ELFUTILS_HEADER(elf)
31 #include <gelf.h>
32
33 int
main(int argc,char * argv[])34 main (int argc, char *argv[])
35 {
36 if (argc != 2)
37 {
38 printf ("No ELF file given as argument");
39 exit (1);
40 }
41
42 const char *fname = argv[1];
43
44 // Initialize libelf.
45 elf_version (EV_CURRENT);
46
47 /* Read the ELF from disk now. */
48 int fd = open (fname, O_RDONLY);
49 if (fd == -1)
50 {
51 printf ("cannot open `%s' read-only: %s\n", fname, strerror (errno));
52 exit (1);
53 }
54
55 Elf *elf = elf_begin (fd, ELF_C_READ, NULL);
56 if (elf == NULL)
57 {
58 printf ("cannot create ELF descriptor read-only: %s\n", elf_errmsg (-1));
59 exit (1);
60 }
61
62 size_t ndx;
63 if (elf_getshdrstrndx (elf, &ndx) != 0)
64 {
65 printf ("cannot get section header table index: %s\n", elf_errmsg (-1));
66 exit (1);
67 }
68
69 if (ndx == SHN_UNDEF)
70 {
71 printf ("ELF file `%s' doesn't have a section header table index", fname);
72 exit (1);
73 }
74
75 Elf_Scn *scn = elf_getscn (elf, ndx);
76 if (scn == NULL)
77 {
78 printf ("Couldn't get section %zd: %s\n", ndx, elf_errmsg (-1));
79 exit (1);
80 }
81
82 void print_strings (void)
83 {
84 GElf_Shdr shdr_mem;
85 GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
86
87 printf ("Strings in section %zd (%s):\n", ndx,
88 ((shdr->sh_flags & SHF_COMPRESSED) != 0
89 ? "compressed" : "uncompressed"));
90
91 size_t off = 0;
92 const char *str = elf_strptr (elf, ndx, off);
93 while (str != NULL)
94 {
95 printf ("[%zx] '%s'\n", off, str);
96 off += strlen (str) + 1;
97 str = elf_strptr (elf, ndx, off);
98 }
99 }
100
101 if (elf_compress (scn, ELFCOMPRESS_ZLIB, 0) < 0)
102 {
103 printf ("Couldn't compress section %zd: %s\n", ndx, elf_errmsg (-1));
104 exit (1);
105 }
106 print_strings ();
107
108 if (elf_compress (scn, 0, 0) < 0)
109 {
110 printf ("Couldn't decompress section %zd: %s\n", ndx, elf_errmsg (-1));
111 exit (1);
112 }
113 print_strings ();
114
115 if (elf_end (elf) != 0)
116 {
117 printf ("failure in elf_end: %s\n", elf_errmsg (-1));
118 exit (1);
119 }
120
121 close (fd);
122
123 return 0;
124 }
125