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/*-
* Copyright (c) 2006 Sam Leffler, Errno Consulting
* Copyright (c) 2006 Atheros Communications, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms 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 NO
* ''WARRANTY'' disclaimer below (''Disclaimer''), without
* modification.
* 2. Redistributions in binary form must reproduce at minimum a
* disclaimer similar to the Disclaimer below and any redistribution
* must be conditioned upon including a substantially similar
* Disclaimer requirement for further binary redistribution.
* 3. Neither the names of the above-listed copyright holders nor the
* names of any contributors may be used to endorse or promote
* product derived from this software without specific prior written
* permission.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT,
* MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE
* FOR 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 DAMAGES.
*
* $Id: //depot/sw/branches/sam_hal/public/wackelf.c#3 $
*/
/*
* Program to zap flags field in the ELF header of an object
* file so that it appears to use VFP soft floating point.
* This is done because there is no standard way to specify
* this on the command line to gcc/binutils.
*
* Derived from code by Olivier Houchard <cognet@freebsd.org>
*/
#include <stdio.h>
#include <stdlib.h>
#include <elf.h>
#include <fcntl.h>
#include <err.h>
#ifdef __linux__
#include <endian.h>
#include <byteswap.h>
#define _LITTLE_ENDIAN __LITTLE_ENDIAN
#define _BIG_ENDIAN __BIG_ENDIAN
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define htobe16(x) __bswap_16((x))
#define htobe32(x) __bswap_32((x))
#define htole16(x) ((uint16_t)(x))
#define htole32(x) ((uint32_t)(x))
#else /* _BYTE_ORDER != _LITTLE_ENDIAN */
#define htobe16(x) ((uint16_t)(x))
#define htobe32(x) ((uint32_t)(x))
#define htole16(x) __bswap_16((x))
#define htole32(x) __bswap_32((x))
#endif /* _BYTE_ORDER == _LITTLE_ENDIAN */
#else
#include <sys/endian.h>
#endif
int
main(int argc, char *argv[])
{
int fd, endian, oflags;
int format = 0x400; /* default to VFP */
Elf32_Ehdr ehdr;
if (argc > 2) {
if (strcmp(argv[1], "-fpa") == 0) {
format = 0x200;
argc--, argv++;
} else if (strcmp(argv[1], "-vfp") == 0) {
format = 0x400;
argc--, argv++;
} else if (strcmp(argv[1], "-none") == 0) {
format = 0;
argc--, argv++;
}
}
if (argc != 2) {
fprintf(stderr, "usage: %s [-fpa|-vfp|-none] file\n", argv[0]);
exit(-1);
}
fd = open(argv[1], O_RDWR);
if (fd < 0)
err(1, "could not open %s", argv[1]);
if (read(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
err(1, "could not read the ELF header");
if (ehdr.e_machine == htole16(EM_ARM))
endian = _LITTLE_ENDIAN;
else if (ehdr.e_machine == htobe16(EM_ARM))
endian = _BIG_ENDIAN;
else
errx(1, "not an ARM ELF object (machine 0x%x)", ehdr.e_machine);
oflags = ehdr.e_flags;
if (endian == _BIG_ENDIAN) {
ehdr.e_flags &= ~htobe32(0x600); /* Remove FPA Soft float */
ehdr.e_flags |= htobe32(format); /* VFP Soft Float */
} else {
ehdr.e_flags &= ~htole32(0x600); /* Remove FPA Soft float */
ehdr.e_flags |= htole32(format); /* VFP Soft Float */
}
printf("%s: e_flags 0x%x => 0x%x\n", argv[1], oflags, ehdr.e_flags);
if (lseek(fd, (off_t) 0, SEEK_SET) != 0)
err(1, "lseek");
if (write(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
err(1, "yow, elf header write failed");
close(fd);
return 0;
}
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