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

   1/*
   2 * hack-coff.c - hack the header of an xcoff file to fill in
   3 * a few fields needed by the Open Firmware xcoff loader on
   4 * Power Macs but not initialized by objcopy.
   5 *
   6 * Copyright (C) Paul Mackerras 1997.
   7 *
   8 * This program is free software; you can redistribute it and/or
   9 * modify it under the terms of the GNU General Public License
  10 * as published by the Free Software Foundation; either version
  11 * 2 of the License, or (at your option) any later version.
  12 */
  13#include <stdio.h>
  14#include <stdlib.h>
  15#include <unistd.h>
  16#include <fcntl.h>
  17#include <string.h>
  18#include "rs6000.h"
  19
  20#define AOUT_MAGIC      0x010b
  21
  22#define get_16be(x)     ((((unsigned char *)(x))[0] << 8) \
  23                         + ((unsigned char *)(x))[1])
  24#define put_16be(x, v)  (((unsigned char *)(x))[0] = (v) >> 8, \
  25                         ((unsigned char *)(x))[1] = (v) & 0xff)
  26#define get_32be(x)     ((((unsigned char *)(x))[0] << 24) \
  27                         + (((unsigned char *)(x))[1] << 16) \
  28                         + (((unsigned char *)(x))[2] << 8) \
  29                         + ((unsigned char *)(x))[3])
  30
  31int
  32main(int ac, char **av)
  33{
  34    int fd;
  35    int i, nsect;
  36    int aoutsz;
  37    struct external_filehdr fhdr;
  38    AOUTHDR aout;
  39    struct external_scnhdr shdr;
  40
  41    if (ac != 2) {
  42        fprintf(stderr, "Usage: hack-coff coff-file\n");
  43        exit(1);
  44    }
  45    if ((fd = open(av[1], 2)) == -1) {
  46        perror(av[2]);
  47        exit(1);
  48    }
  49    if (read(fd, &fhdr, sizeof(fhdr)) != sizeof(fhdr))
  50        goto readerr;
  51    i = get_16be(fhdr.f_magic);
  52    if (i != U802TOCMAGIC && i != U802WRMAGIC && i != U802ROMAGIC) {
  53        fprintf(stderr, "%s: not an xcoff file\n", av[1]);
  54        exit(1);
  55    }
  56    aoutsz = get_16be(fhdr.f_opthdr);
  57    if (read(fd, &aout, aoutsz) != aoutsz)
  58        goto readerr;
  59    nsect = get_16be(fhdr.f_nscns);
  60    for (i = 0; i < nsect; ++i) {
  61        if (read(fd, &shdr, sizeof(shdr)) != sizeof(shdr))
  62            goto readerr;
  63        if (strcmp(shdr.s_name, ".text") == 0) {
  64            put_16be(aout.o_snentry, i+1);
  65            put_16be(aout.o_sntext, i+1);
  66        } else if (strcmp(shdr.s_name, ".data") == 0) {
  67            put_16be(aout.o_sndata, i+1);
  68        } else if (strcmp(shdr.s_name, ".bss") == 0) {
  69            put_16be(aout.o_snbss, i+1);
  70        }
  71    }
  72    put_16be(aout.magic, AOUT_MAGIC);
  73    if (lseek(fd, (long) sizeof(struct external_filehdr), 0) == -1
  74        || write(fd, &aout, aoutsz) != aoutsz) {
  75        fprintf(stderr, "%s: write error\n", av[1]);
  76        exit(1);
  77    }
  78    close(fd);
  79    exit(0);
  80
  81readerr:
  82    fprintf(stderr, "%s: read error or file too short\n", av[1]);
  83    exit(1);
  84}
  85