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/* Return section header.
Copyright (C) 1998, 1999, 2000, 2001, 2002, 2005 Red Hat, Inc.
Written by Ulrich Drepper <drepper@redhat.com>, 1998.
This program 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.
This program 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, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <assert.h>
#include <unistd.h>
#include "libelfP.h"
#include "common.h"
#ifndef LIBELFBITS
# define LIBELFBITS 32
#endif
ElfW2(LIBELFBITS,Shdr) *
elfw2(LIBELFBITS,getshdr) (scn)
Elf_Scn *scn;
{
ElfW2(LIBELFBITS,Shdr) *result;
if (scn == NULL)
return NULL;
if (unlikely (scn->elf->state.elf.ehdr == NULL))
{
__libelf_seterrno (ELF_E_WRONG_ORDER_EHDR);
return NULL;
}
if (unlikely (scn->elf->class != ELFW(ELFCLASS,LIBELFBITS)))
{
__libelf_seterrno (ELF_E_INVALID_CLASS);
return NULL;
}
result = scn->shdr.ELFW(e,LIBELFBITS);
if (result == NULL)
{
/* Read the section header table. */
Elf *elf = scn->elf;
ElfW2(LIBELFBITS,Ehdr) *ehdr = elf->state.ELFW(elf,LIBELFBITS).ehdr;
rwlock_wrlock (elf->lock);
/* Try again, maybe the data is there now. */
result = scn->shdr.ELFW(e,LIBELFBITS);
if (result != NULL)
goto out;
size_t shnum;
if (INTUSE (elf_getshnum) (elf, &shnum) != 0)
goto out;
size_t size = shnum * sizeof (ElfW2(LIBELFBITS,Shdr));
/* Allocate memory for the program headers. We know the number
of entries from the ELF header. */
ElfW2(LIBELFBITS,Shdr) *shdr = elf->state.ELFW(elf,LIBELFBITS).shdr =
(ElfW2(LIBELFBITS,Shdr) *) malloc (size);
if (elf->state.ELFW(elf,LIBELFBITS).shdr == NULL)
{
__libelf_seterrno (ELF_E_NOMEM);
goto out;
}
elf->state.ELFW(elf,LIBELFBITS).shdr_malloced = 1;
if (elf->map_address != NULL)
{
ElfW2(LIBELFBITS,Shdr) *notcvt;
/* All the data is already mapped. If we could use it
directly this would already have happened. */
assert (ehdr->e_ident[EI_DATA] != MY_ELFDATA
|| (! ALLOW_UNALIGNED
&& (ehdr->e_shoff
& (__alignof__ (ElfW2(LIBELFBITS,Shdr)) - 1)) != 0));
/* Now copy the data and at the same time convert the byte
order. */
if (ALLOW_UNALIGNED
|| (ehdr->e_shoff
& (__alignof__ (ElfW2(LIBELFBITS,Shdr)) - 1)) == 0)
notcvt = (ElfW2(LIBELFBITS,Shdr) *)
((char *) elf->map_address
+ elf->start_offset + ehdr->e_shoff);
else
{
notcvt = (ElfW2(LIBELFBITS,Shdr) *) alloca (size);
memcpy (notcvt, ((char *) elf->map_address
+ elf->start_offset + ehdr->e_shoff),
size);
}
for (size_t cnt = 0; cnt < shnum; ++cnt)
{
CONVERT_TO (shdr[cnt].sh_name, notcvt[cnt].sh_name);
CONVERT_TO (shdr[cnt].sh_type, notcvt[cnt].sh_type);
CONVERT_TO (shdr[cnt].sh_flags, notcvt[cnt].sh_flags);
CONVERT_TO (shdr[cnt].sh_addr, notcvt[cnt].sh_addr);
CONVERT_TO (shdr[cnt].sh_offset, notcvt[cnt].sh_offset);
CONVERT_TO (shdr[cnt].sh_size, notcvt[cnt].sh_size);
CONVERT_TO (shdr[cnt].sh_link, notcvt[cnt].sh_link);
CONVERT_TO (shdr[cnt].sh_info, notcvt[cnt].sh_info);
CONVERT_TO (shdr[cnt].sh_addralign, notcvt[cnt].sh_addralign);
CONVERT_TO (shdr[cnt].sh_entsize, notcvt[cnt].sh_entsize);
}
}
else if (elf->fildes != -1)
{
/* Read the header. */
if ((size_t) pread (elf->fildes,
elf->state.ELFW(elf,LIBELFBITS).shdr, size,
elf->start_offset + ehdr->e_shoff) != size)
{
/* Severe problems. We cannot read the data. */
__libelf_seterrno (ELF_E_READ_ERROR);
goto free_and_out;
}
/* If the byte order of the file is not the same as the one
of the host convert the data now. */
if (ehdr->e_ident[EI_DATA] != MY_ELFDATA)
for (size_t cnt = 0; cnt < shnum; ++cnt)
{
CONVERT (shdr[cnt].sh_name);
CONVERT (shdr[cnt].sh_type);
CONVERT (shdr[cnt].sh_flags);
CONVERT (shdr[cnt].sh_addr);
CONVERT (shdr[cnt].sh_offset);
CONVERT (shdr[cnt].sh_size);
CONVERT (shdr[cnt].sh_link);
CONVERT (shdr[cnt].sh_info);
CONVERT (shdr[cnt].sh_addralign);
CONVERT (shdr[cnt].sh_entsize);
}
}
else
{
/* The file descriptor was already enabled and not all data was
read. Undo the allocation. */
__libelf_seterrno (ELF_E_FD_DISABLED);
free_and_out:
free (shdr);
elf->state.ELFW(elf,LIBELFBITS).shdr = NULL;
elf->state.ELFW(elf,LIBELFBITS).shdr_malloced = 0;
goto out;
}
/* Set the pointers in the `scn's. */
for (size_t cnt = 0; cnt < shnum; ++cnt)
elf->state.ELFW(elf,LIBELFBITS).scns.data[cnt].shdr.ELFW(e,LIBELFBITS)
= &elf->state.ELFW(elf,LIBELFBITS).shdr[cnt];
result = scn->shdr.ELFW(e,LIBELFBITS);
assert (result != NULL);
out:
rwlock_unlock (elf->lock);
}
return result;
}
INTDEF(elfw2(LIBELFBITS,getshdr))
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