File: /usr/src/linux/arch/ppc/boot/utils/hack-coff.c
1 /*
2 * BK Id: SCCS/s.hack-coff.c 1.8 05/18/01 06:20:29 patch
3 */
4 /*
5 * hack-coff.c - hack the header of an xcoff file to fill in
6 * a few fields needed by the Open Firmware xcoff loader on
7 * Power Macs but not initialized by objcopy.
8 *
9 * Copyright (C) Paul Mackerras 1997.
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 */
16 #include <stdio.h>
17 #include <unistd.h>
18 #include <fcntl.h>
19 #include "rs6000.h"
20
21 #define AOUT_MAGIC 0x010b
22
23 #define get_16be(x) ((((unsigned char *)(x))[0] << 8) \
24 + ((unsigned char *)(x))[1])
25 #define put_16be(x, v) (((unsigned char *)(x))[0] = (v) >> 8, \
26 ((unsigned char *)(x))[1] = (v) & 0xff)
27 #define get_32be(x) ((((unsigned char *)(x))[0] << 24) \
28 + (((unsigned char *)(x))[1] << 16) \
29 + (((unsigned char *)(x))[2] << 8) \
30 + ((unsigned char *)(x))[3])
31
32 int
33 main(int ac, char **av)
34 {
35 int fd;
36 int i, nsect;
37 int aoutsz;
38 struct external_filehdr fhdr;
39 AOUTHDR aout;
40 struct external_scnhdr shdr;
41
42 if (ac != 2) {
43 fprintf(stderr, "Usage: hack-coff coff-file\n");
44 exit(1);
45 }
46 if ((fd = open(av[1], 2)) == -1) {
47 perror(av[2]);
48 exit(1);
49 }
50 if (read(fd, &fhdr, sizeof(fhdr)) != sizeof(fhdr))
51 goto readerr;
52 i = get_16be(fhdr.f_magic);
53 if (i != U802TOCMAGIC && i != U802WRMAGIC && i != U802ROMAGIC) {
54 fprintf(stderr, "%s: not an xcoff file\n", av[1]);
55 exit(1);
56 }
57 aoutsz = get_16be(fhdr.f_opthdr);
58 if (read(fd, &aout, aoutsz) != aoutsz)
59 goto readerr;
60 nsect = get_16be(fhdr.f_nscns);
61 for (i = 0; i < nsect; ++i) {
62 if (read(fd, &shdr, sizeof(shdr)) != sizeof(shdr))
63 goto readerr;
64 if (strcmp(shdr.s_name, ".text") == 0) {
65 put_16be(aout.o_snentry, i+1);
66 put_16be(aout.o_sntext, i+1);
67 } else if (strcmp(shdr.s_name, ".data") == 0) {
68 put_16be(aout.o_sndata, i+1);
69 } else if (strcmp(shdr.s_name, ".bss") == 0) {
70 put_16be(aout.o_snbss, i+1);
71 }
72 }
73 put_16be(aout.magic, AOUT_MAGIC);
74 if (lseek(fd, (long) sizeof(struct external_filehdr), 0) == -1
75 || write(fd, &aout, aoutsz) != aoutsz) {
76 fprintf(stderr, "%s: write error\n", av[1]);
77 exit(1);
78 }
79 close(fd);
80 exit(0);
81
82 readerr:
83 fprintf(stderr, "%s: read error or file too short\n", av[1]);
84 exit(1);
85 }
86