xref: /third_party/elfutils/tests/zstrptr.c (revision da0c48c4)
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
33static void
34print_strings (Elf_Scn *scn, Elf *elf, size_t ndx)
35{
36  GElf_Shdr shdr_mem;
37  GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
38
39  printf ("Strings in section %zd (%s):\n", ndx,
40	  ((shdr->sh_flags & SHF_COMPRESSED) != 0
41	   ? "compressed" : "uncompressed"));
42
43  size_t off = 0;
44  const char *str = elf_strptr (elf, ndx, off);
45  while (str != NULL)
46    {
47      printf ("[%zx] '%s'\n", off, str);
48      off += strlen (str) + 1;
49      str = elf_strptr (elf, ndx, off);
50    }
51}
52
53int
54main (int argc, char *argv[])
55{
56  if (argc != 2)
57    {
58      printf ("No ELF file given as argument");
59      exit (1);
60    }
61
62  const char *fname = argv[1];
63
64  // Initialize libelf.
65  elf_version (EV_CURRENT);
66
67  /* Read the ELF from disk now.  */
68  int fd = open (fname, O_RDONLY);
69  if (fd == -1)
70    {
71      printf ("cannot open `%s' read-only: %s\n", fname, strerror (errno));
72      exit (1);
73    }
74
75  Elf *elf = elf_begin (fd, ELF_C_READ, NULL);
76  if (elf == NULL)
77    {
78      printf ("cannot create ELF descriptor read-only: %s\n", elf_errmsg (-1));
79      exit (1);
80    }
81
82  size_t ndx;
83  if (elf_getshdrstrndx (elf, &ndx) != 0)
84    {
85      printf ("cannot get section header table index: %s\n", elf_errmsg (-1));
86      exit (1);
87    }
88
89  if (ndx == SHN_UNDEF)
90    {
91      printf ("ELF file `%s' doesn't have a section header table index", fname);
92      exit (1);
93    }
94
95  Elf_Scn *scn = elf_getscn (elf, ndx);
96  if (scn == NULL)
97    {
98      printf ("Couldn't get section %zd: %s\n", ndx, elf_errmsg (-1));
99      exit (1);
100    }
101
102  if (elf_compress (scn, ELFCOMPRESS_ZLIB, 0) < 0)
103    {
104      printf ("Couldn't compress section %zd: %s\n", ndx, elf_errmsg (-1));
105      exit (1);
106    }
107  print_strings (scn, elf, ndx);
108
109  if (elf_compress (scn, 0, 0) < 0)
110    {
111      printf ("Couldn't decompress section %zd: %s\n", ndx, elf_errmsg (-1));
112      exit (1);
113    }
114  print_strings (scn, elf, ndx);
115
116  if (elf_end (elf) != 0)
117    {
118      printf ("failure in elf_end: %s\n", elf_errmsg (-1));
119      exit (1);
120    }
121
122  close (fd);
123
124  return 0;
125}
126