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/* Test program for elf_update function.
Copyright (C) 2000, 2002, 2005 Red Hat, Inc.
This file is part of Red Hat elfutils.
Written by Ulrich Drepper <drepper@redhat.com>, 2000.
Red Hat elfutils 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; version 2 of the License.
Red Hat 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 Red Hat elfutils; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
Red Hat elfutils is an included package of the Open Invention Network.
An included package of the Open Invention Network is a package for which
Open Invention Network licensees cross-license their patents. No patent
license is granted, either expressly or impliedly, by designation as an
included package. Should you wish to participate in the Open Invention
Network licensing program, please visit www.openinventionnetwork.com
<http://www.openinventionnetwork.com>. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <errno.h>
#include <fcntl.h>
#include <libelf.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include ELFUTILS_HEADER(ebl)
int
main (int argc, char *argv[] __attribute__ ((unused)))
{
const char *fname = "xxx";
int fd;
Elf *elf;
Elf32_Ehdr *ehdr;
Elf32_Phdr *phdr;
Elf_Scn *scn;
Elf32_Shdr *shdr;
Elf_Data *data;
struct Ebl_Strtab *shst;
struct Ebl_Strent *shstrtabse;
int i;
fd = open (fname, O_RDWR | O_CREAT | O_TRUNC, 0666);
if (fd == -1)
{
printf ("cannot open `%s': %s\n", fname, strerror (errno));
exit (1);
}
elf_version (EV_CURRENT);
elf_fill (0x42);
elf = elf_begin (fd, ELF_C_WRITE, NULL);
if (elf == NULL)
{
printf ("cannot create ELF descriptor: %s\n", elf_errmsg (-1));
exit (1);
}
/* Create an ELF header. */
ehdr = elf32_newehdr (elf);
if (ehdr == NULL)
{
printf ("cannot create ELF header: %s\n", elf_errmsg (-1));
exit (1);
}
/* Print the ELF header values. */
if (argc > 1)
{
for (i = 0; i < EI_NIDENT; ++i)
printf (" %02x", ehdr->e_ident[i]);
printf ("\
\ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
"shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
"phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
ehdr->e_shnum, ehdr->e_shstrndx);
}
ehdr->e_ident[0] = 42;
ehdr->e_ident[4] = 1;
ehdr->e_ident[5] = 1;
ehdr->e_ident[6] = 2;
ehdr->e_type = ET_EXEC;
ehdr->e_version = 1;
ehdr->e_ehsize = 1;
elf_flagehdr (elf, ELF_C_SET, ELF_F_DIRTY);
/* Create the program header. */
phdr = elf32_newphdr (elf, 1);
if (phdr == NULL)
{
printf ("cannot create program header: %s\n", elf_errmsg (-1));
exit (1);
}
phdr[0].p_type = PT_PHDR;
elf_flagphdr (elf, ELF_C_SET, ELF_F_DIRTY);
shst = ebl_strtabinit (true);
scn = elf_newscn (elf);
if (scn == NULL)
{
printf ("cannot create SHSTRTAB section: %s\n", elf_errmsg (-1));
exit (1);
}
shdr = elf32_getshdr (scn);
if (shdr == NULL)
{
printf ("cannot get header for SHSTRTAB section: %s\n", elf_errmsg (-1));
exit (1);
}
shstrtabse = ebl_strtabadd (shst, ".shstrtab", 0);
shdr->sh_type = SHT_STRTAB;
shdr->sh_flags = 0;
shdr->sh_addr = 0;
shdr->sh_link = SHN_UNDEF;
shdr->sh_info = SHN_UNDEF;
shdr->sh_addralign = 1;
shdr->sh_entsize = 0;
/* We have to store the section index in the ELF header. */
ehdr->e_shstrndx = elf_ndxscn (scn);
data = elf_newdata (scn);
if (data == NULL)
{
printf ("cannot create data SHSTRTAB section: %s\n", elf_errmsg (-1));
exit (1);
}
/* No more sections, finalize the section header string table. */
ebl_strtabfinalize (shst, data);
shdr->sh_name = ebl_strtaboffset (shstrtabse);
/* Let the library compute the internal structure information. */
if (elf_update (elf, ELF_C_NULL) < 0)
{
printf ("failure in elf_update(NULL): %s\n", elf_errmsg (-1));
exit (1);
}
ehdr = elf32_getehdr (elf);
phdr[0].p_offset = ehdr->e_phoff;
phdr[0].p_offset = ehdr->e_phoff;
phdr[0].p_vaddr = ehdr->e_phoff;
phdr[0].p_paddr = ehdr->e_phoff;
phdr[0].p_flags = PF_R | PF_X;
phdr[0].p_filesz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
phdr[0].p_memsz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
phdr[0].p_align = sizeof (Elf32_Word);
/* Write out the file. */
if (elf_update (elf, ELF_C_WRITE) < 0)
{
printf ("failure in elf_update(WRITE): %s\n", elf_errmsg (-1));
exit (1);
}
/* We don't need the string table anymore. */
ebl_strtabfree (shst);
/* And the data allocated in the .shstrtab section. */
free (data->d_buf);
/* Print the ELF header values. */
if (argc > 1)
{
for (i = 0; i < EI_NIDENT; ++i)
printf (" %02x", ehdr->e_ident[i]);
printf ("\
\ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
"shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
"phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
ehdr->e_shnum, ehdr->e_shstrndx);
}
if (elf_end (elf) != 0)
{
printf ("failure in elf_end: %s\n", elf_errmsg (-1));
exit (1);
}
return 0;
}
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