/*      $NetBSD: fixcoff.c,v 1.13 2024/10/29 11:37:57 kre Exp $ */

/*
 * Copyright (c) 1999 National Aeronautics & Space Administration
 * All rights reserved.
 *
 * This software was written by William Studenmund of the
 * Numerical Aerospace Similation Facility, NASA Ames Research Center.
 *
 * 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.
 * 3. Neither the name of the National Aeronautics & Space Administration
 *    nor the names of its contributors may be used to endorse or promote
 *    products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NATIONAL AERONAUTICS & SPACE ADMINISTRATION
 * ``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 ADMINISTRATION OR CONTRIB-
 * UTORS 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.
 */

/*
 * This program fixes up the extended xcoff headers generated when an elf
 * file is turned into an xcoff one with the current objcopy. It should
 * go away someday, when objcopy will correctly fix up the output xcoff
 *
 * Partially inspired by hack-coff, written by Paul Mackerras.
 */

#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#else   /* HAVE_NBTOOL_CONFIG_H */
#include <sys/endian.h>
#endif  /* HAVE_NBTOOL_CONFIG_H */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>

struct filehdr {
#define U802WRMAGIC     0730
#define U802ROMAGIC     0735
#define U802TOCMAGIC    0737
        char f_magic[2];
        char f_nsect[2];
        char f_time[4];
        char f_symtab[4];
        char f_nsyms[4];
        char f_opthdr[2];
        char f_flags[2];
};

struct sectionhdr {
        char    s_name[8];
        char    s_paddr[4];
        char    s_vaddr[4];
        char    s_size[4];
        char    s_section[4];
        char    s_reloc[4];
        char    s_lineno[4];
        char    s_nreloc[2];
        char    s_nlineno[2];
        char    s_flags[4];
};

struct aouthdr {
        char    magic[2];
        char    vstamp[2];
        char    tsize[4];
        char    dsize[4];
        char    bsize[4];
        char    entry[4];
        char    text_start[4];
        char    data_start[4];
#define SMALL_AOUTSZ    28
        char    o_toc[4];
        char    o_snentry[2];
        char    o_sntext[2];
        char    o_sndata[2];
        char    o_sntoc[2];
        char    o_snloader[2];
        char    o_snbss[2];
        char    o_algntext[2];
        char    o_algndata[2];
        char    o_modtype[2];
        char    o_cputype[2];
        char    o_maxstack[4];
        char    o_maxdata[4];
        char    o_resv2[12];
};
#define RS6K_AOUTHDR_ZMAGIC     0x010B

void
usage(const char *prog)
{
        fprintf(stderr, "Usage: %s [-h] | [<file to fix>]\n", prog);
}

void
help(const char *prog)
{
        fprintf(stderr, "%s\tis designed to fix the xcoff headers in a\n",prog);
        fprintf(stderr,
"\tbinary generated using objcopy from a non-xcoff source.\n");
        usage(prog);
        exit(0);
}

int
main(int argc, char * const *argv)
{
        int     fd, i, n, ch;
        struct  filehdr fh;
        struct  aouthdr aoh;
        struct  sectionhdr sh;

        while ((ch = getopt(argc, argv, "h")) != -1)
            switch (ch) {
                case 'h':
                help(getprogname());
        }

        argc -= optind;
        argv += optind;

        if (argc != 1) {
                usage(getprogname());
                exit(1);
        }

        if ((fd = open(argv[0], O_RDWR, 0)) == -1)
                err(i, "%s", argv[0]);

        /*
         * Make sure it looks like an xcoff file..
         */
        if (read(fd, &fh, sizeof(fh)) != sizeof(fh))
                err(1, "%s reading header", argv[0]);

        i = be16toh(*(uint16_t *)fh.f_magic);
        if ((i != U802WRMAGIC) && (i != U802ROMAGIC) && (i != U802TOCMAGIC))
                errx(1, "%s: not a valid xcoff file", argv[0]);

        /* Does the AOUT "Optional header" make sense? */
        i = be16toh(*(uint16_t *)fh.f_opthdr);

        if (i == SMALL_AOUTSZ)
                errx(1, "%s: file has small \"optional\" header, inappropriate for use with %s", argv[0], getprogname());
        else if (i != sizeof(aoh))
                errx(1, "%s: invalid \"optional\" header", argv[0]);

        if (read(fd, &aoh, i) != i)
                err(1, "%s reading \"optional\" header", argv[0]);

        /* Now start filing in the AOUT header */
        *(uint16_t *)aoh.magic = htobe16(RS6K_AOUTHDR_ZMAGIC);
        n = be16toh(*(uint16_t *)fh.f_nsect);

        for (i = 0; i < n; i++) {
                if (read(fd, &sh, sizeof(sh)) != sizeof(sh))
                        err(1, "%s reading section headers", argv[0]);
                if (strcmp(sh.s_name, ".text") == 0) {
                        *(uint16_t *)(aoh.o_snentry) = htobe16(i+1);
                        *(uint16_t *)(aoh.o_sntext) = htobe16(i+1);
                } else if (strcmp(sh.s_name, ".data") == 0) {
                        *(uint16_t *)(aoh.o_sndata) = htobe16(i+1);
                } else if (strcmp(sh.s_name, ".bss") == 0) {
                        *(uint16_t *)(aoh.o_snbss) = htobe16(i+1);
                }
        }

        /* now write it out */
        if (pwrite(fd, &aoh, sizeof(aoh), sizeof(struct filehdr))
                        != sizeof(aoh))
                err(1, "%s writing modified header", argv[0]);
        close(fd);
        exit(0);
}