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
33int
34main (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