freebsd-skq/contrib/elftoolchain/libelf/elf_rand.c

60 lines
2.0 KiB
C

/*-
* Copyright (c) 2006,2008 Joseph Koshy
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#include <ar.h>
#include <libelf.h>
#include "_libelf.h"
ELFTC_VCSID("$Id: elf_rand.c 2225 2011-11-26 18:55:54Z jkoshy $");
off_t
elf_rand(Elf *ar, off_t offset)
{
struct ar_hdr *arh;
if (ar == NULL || ar->e_kind != ELF_K_AR ||
(offset & 1) || offset < SARMAG ||
offset + sizeof(struct ar_hdr) >= ar->e_rawsize) {
LIBELF_SET_ERROR(ARGUMENT, 0);
return 0;
}
arh = (struct ar_hdr *) (ar->e_rawfile + offset);
/* a too simple sanity check */
if (arh->ar_fmag[0] != '`' || arh->ar_fmag[1] != '\n') {
LIBELF_SET_ERROR(ARCHIVE, 0);
return 0;
}
ar->e_u.e_ar.e_next = offset;
return (offset);
}