blob: a9cfc181e188aff2427c5c1e97718f20ab0b0a4b [file] [log] [blame]
/* Get symbol information and separate section index from symbol table
at the given index.
Copyright (C) 2000, 2001, 2002 Red Hat, Inc.
This file is part of Red Hat elfutils.
Written by Ulrich Drepper <>, 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
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.
In addition, as a special exception, Red Hat, Inc. gives You the
additional right to link the code of Red Hat elfutils with code licensed
under any Open Source Initiative certified open source license
( which requires the
distribution of source code with any binary distribution and to
distribute linked combinations of the two. Non-GPL Code permitted under
this exception must only link to the code of Red Hat elfutils through
those well defined interfaces identified in the file named EXCEPTION
found in the source code files (the "Approved Interfaces"). The files
of Non-GPL Code may instantiate templates or use macros or inline
functions from the Approved Interfaces without causing the resulting
work to be covered by the GNU General Public License. Only Red Hat,
Inc. may make changes or additions to the list of Approved Interfaces.
Red Hat's grant of this exception is conditioned upon your not adding
any new exceptions. If you wish to add a new Approved Interface or
exception, please contact Red Hat. You must obey the GNU General Public
License in all respects for all of the Red Hat elfutils code and other
code used in conjunction with Red Hat elfutils except the Non-GPL Code
covered by this exception. If you modify this file, you may extend this
exception to your version of the file, but you are not obligated to do
so. If you do not wish to provide this exception without modification,
you must delete this exception statement from your version and license
this file solely under the GPL without exception.
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
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Network licensing program, please visit
<>. */
# include <config.h>
#include <assert.h>
#include <gelf.h>
#include <string.h>
#include "libelfP.h"
GElf_Sym *
gelf_getsymshndx (symdata, shndxdata, ndx, dst, dstshndx)
Elf_Data *symdata;
Elf_Data *shndxdata;
int ndx;
GElf_Sym *dst;
Elf32_Word *dstshndx;
Elf_Data_Scn *symdata_scn = (Elf_Data_Scn *) symdata;
Elf_Data_Scn *shndxdata_scn = (Elf_Data_Scn *) shndxdata;
GElf_Sym *result = NULL;
Elf32_Word shndx = 0;
if (symdata == NULL)
return NULL;
if (unlikely (symdata->d_type != ELF_T_SYM)
|| (likely (shndxdata_scn != NULL)
&& unlikely (shndxdata->d_type != ELF_T_WORD)))
__libelf_seterrno (ELF_E_INVALID_HANDLE);
return NULL;
rwlock_rdlock (symdata_scn->s->elf->lock);
/* The user is not required to pass a data descriptor for an extended
section index table. */
if (likely (shndxdata_scn != NULL))
if (unlikely ((ndx + 1) * sizeof (Elf32_Word) > shndxdata_scn->d.d_size))
__libelf_seterrno (ELF_E_INVALID_INDEX);
goto out;
shndx = ((Elf32_Word *) shndxdata_scn->d.d_buf)[ndx];
/* This is the one place where we have to take advantage of the fact
that an `Elf_Data' pointer is also a pointer to `Elf_Data_Scn'.
The interface is broken so that it requires this hack. */
if (symdata_scn->s->elf->class == ELFCLASS32)
Elf32_Sym *src;
/* Here it gets a bit more complicated. The format of the symbol
table entries has to be adopted. The user better has provided
a buffer where we can store the information. While copying the
data we are converting the format. */
if (unlikely ((ndx + 1) * sizeof (Elf32_Sym) > symdata->d_size))
__libelf_seterrno (ELF_E_INVALID_INDEX);
goto out;
src = &((Elf32_Sym *) symdata->d_buf)[ndx];
/* This might look like a simple copy operation but it's
not. There are zero- and sign-extensions going on. */
#define COPY(name) \
dst->name = src->name
COPY (st_name);
/* Please note that we can simply copy the `st_info' element since
the definitions of ELFxx_ST_BIND and ELFxx_ST_TYPE are the same
for the 64 bit variant. */
COPY (st_info);
COPY (st_other);
COPY (st_shndx);
COPY (st_value);
COPY (st_size);
/* If this is a 64 bit object it's easy. */
assert (sizeof (GElf_Sym) == sizeof (Elf64_Sym));
/* The data is already in the correct form. Just make sure the
index is OK. */
if (unlikely ((ndx + 1) * sizeof (GElf_Sym) > symdata->d_size))
__libelf_seterrno (ELF_E_INVALID_INDEX);
goto out;
*dst = ((GElf_Sym *) symdata->d_buf)[ndx];
/* Now we can store the section index. */
if (dstshndx != NULL)
*dstshndx = shndx;
result = dst;
rwlock_unlock (symdata_scn->s->elf->lock);
return result;