buildroot

/* http://www.muppetlabs.com/~breadbox/software/elfkickers.html */

​

/* sstrip: Copyright (C) 1999-2001 by Brian Raiter, under the GNU

 * General Public License. No warranty. See COPYING for details.

 *

 * Aug 23, 2004 Hacked by Manuel Novoa III <mjn3@codepoet.org> to

 * handle targets of different endianness and/or elf class, making

 * it more useful in a cross-devel environment.

 */

​

/* ============== original README ===================

 *

 * sstrip is a small utility that removes the contents at the end of an

 * ELF file that are not part of the program's memory image.

 * 

 * Most ELF executables are built with both a program header table and a

 * section header table. However, only the former is required in order

 * for the OS to load, link and execute a program. sstrip attempts to

 * extract the ELF header, the program header table, and its contents,

 * leaving everything else in the bit bucket. It can only remove parts of

 * the file that occur at the end, after the parts to be saved. However,

 * this almost always includes the section header table, and occasionally

 * a few random sections that are not used when running a program.

 * 

 * It should be noted that the GNU bfd library is (understandably)

 * dependent on the section header table as an index to the file's

 * contents. Thus, an executable file that has no section header table

 * cannot be used with gdb, objdump, or any other program based upon the

 * bfd library, at all. In fact, the program will not even recognize the

 * file as a valid executable. (This limitation is noted in the source

 * code comments for bfd, and is marked "FIXME", so this may change at

 * some future date. However, I would imagine that it is a pretty

 * low-priority item, as executables without a section header table are

 * rare in the extreme.) This probably also explains why strip doesn't

 * offer the option to do this.

 * 

 * Shared library files may also have their section header table removed.

 * Such a library will still function; however, it will no longer be

 * possible for a compiler to link a new program against it.

 * 

 * As an added bonus, sstrip also tries to removes trailing zero bytes

 * from the end of the file. (This normally cannot be done with an

 * executable that has a section header table.)

 * 

 * sstrip is a very simplistic program. It depends upon the common

 * practice of putting the parts of the file that contribute to the

 * memory image at the front, and the remaining material at the end. This

 * permits it to discard the latter material without affecting file

 * offsets and memory addresses in what remains. Of course, the ELF

 * standard permits files to be organized in almost any order, so if a

 * pathological linker decided to put its section headers at the top,

 * sstrip would be useless on such executables.

 */

​

#include    <stdio.h>

#include    <stdlib.h>

#include    <string.h>

#include    <errno.h>

#include    <unistd.h>

#include    <fcntl.h>

#include    <elf.h>

#include    <endian.h>

#include    <byteswap.h>