linux-sg2042/arch/powerpc/boot/hack-coff.c

85 lines
2.3 KiB
C

/*
* hack-coff.c - hack the header of an xcoff file to fill in
* a few fields needed by the Open Firmware xcoff loader on
* Power Macs but not initialized by objcopy.
*
* Copyright (C) Paul Mackerras 1997.
*
* 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; either version
* 2 of the License, or (at your option) any later version.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include "rs6000.h"
#define AOUT_MAGIC 0x010b
#define get_16be(x) ((((unsigned char *)(x))[0] << 8) \
+ ((unsigned char *)(x))[1])
#define put_16be(x, v) (((unsigned char *)(x))[0] = (v) >> 8, \
((unsigned char *)(x))[1] = (v) & 0xff)
#define get_32be(x) ((((unsigned char *)(x))[0] << 24) \
+ (((unsigned char *)(x))[1] << 16) \
+ (((unsigned char *)(x))[2] << 8) \
+ ((unsigned char *)(x))[3])
int
main(int ac, char **av)
{
int fd;
int i, nsect;
int aoutsz;
struct external_filehdr fhdr;
AOUTHDR aout;
struct external_scnhdr shdr;
if (ac != 2) {
fprintf(stderr, "Usage: hack-coff coff-file\n");
exit(1);
}
if ((fd = open(av[1], 2)) == -1) {
perror(av[2]);
exit(1);
}
if (read(fd, &fhdr, sizeof(fhdr)) != sizeof(fhdr))
goto readerr;
i = get_16be(fhdr.f_magic);
if (i != U802TOCMAGIC && i != U802WRMAGIC && i != U802ROMAGIC) {
fprintf(stderr, "%s: not an xcoff file\n", av[1]);
exit(1);
}
aoutsz = get_16be(fhdr.f_opthdr);
if (read(fd, &aout, aoutsz) != aoutsz)
goto readerr;
nsect = get_16be(fhdr.f_nscns);
for (i = 0; i < nsect; ++i) {
if (read(fd, &shdr, sizeof(shdr)) != sizeof(shdr))
goto readerr;
if (strcmp(shdr.s_name, ".text") == 0) {
put_16be(aout.o_snentry, i+1);
put_16be(aout.o_sntext, i+1);
} else if (strcmp(shdr.s_name, ".data") == 0) {
put_16be(aout.o_sndata, i+1);
} else if (strcmp(shdr.s_name, ".bss") == 0) {
put_16be(aout.o_snbss, i+1);
}
}
put_16be(aout.magic, AOUT_MAGIC);
if (lseek(fd, (long) sizeof(struct external_filehdr), 0) == -1
|| write(fd, &aout, aoutsz) != aoutsz) {
fprintf(stderr, "%s: write error\n", av[1]);
exit(1);
}
close(fd);
exit(0);
readerr:
fprintf(stderr, "%s: read error or file too short\n", av[1]);
exit(1);
}