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/* Test program for elf_strptr function.
Copyright (C) 2015 Red Hat, Inc.
This file is part of elfutils.
This file is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
elfutils is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include ELFUTILS_HEADER(elf)
#include <gelf.h>
static void
print_strings (Elf_Scn *scn, Elf *elf, size_t ndx)
{
GElf_Shdr shdr_mem;
GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
printf ("Strings in section %zd (%s):\n", ndx,
((shdr->sh_flags & SHF_COMPRESSED) != 0
? "compressed" : "uncompressed"));
size_t off = 0;
const char *str = elf_strptr (elf, ndx, off);
while (str != NULL)
{
printf ("[%zx] '%s'\n", off, str);
off += strlen (str) + 1;
str = elf_strptr (elf, ndx, off);
}
}
int
main (int argc, char *argv[])
{
if (argc != 2)
{
printf ("No ELF file given as argument");
exit (1);
}
const char *fname = argv[1];
// Initialize libelf.
elf_version (EV_CURRENT);
/* Read the ELF from disk now. */
int fd = open (fname, O_RDONLY);
if (fd == -1)
{
printf ("cannot open `%s' read-only: %s\n", fname, strerror (errno));
exit (1);
}
Elf *elf = elf_begin (fd, ELF_C_READ, NULL);
if (elf == NULL)
{
printf ("cannot create ELF descriptor read-only: %s\n", elf_errmsg (-1));
exit (1);
}
size_t ndx;
if (elf_getshdrstrndx (elf, &ndx) != 0)
{
printf ("cannot get section header table index: %s\n", elf_errmsg (-1));
exit (1);
}
if (ndx == SHN_UNDEF)
{
printf ("ELF file `%s' doesn't have a section header table index", fname);
exit (1);
}
Elf_Scn *scn = elf_getscn (elf, ndx);
if (scn == NULL)
{
printf ("Couldn't get section %zd: %s\n", ndx, elf_errmsg (-1));
exit (1);
}
if (elf_compress (scn, ELFCOMPRESS_ZLIB, 0) < 0)
{
printf ("Couldn't compress section %zd: %s\n", ndx, elf_errmsg (-1));
exit (1);
}
print_strings (scn, elf, ndx);
if (elf_compress (scn, 0, 0) < 0)
{
printf ("Couldn't decompress section %zd: %s\n", ndx, elf_errmsg (-1));
exit (1);
}
print_strings (scn, elf, ndx);
if (elf_end (elf) != 0)
{
printf ("failure in elf_end: %s\n", elf_errmsg (-1));
exit (1);
}
close (fd);
return 0;
}
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