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/* Generate parameters for an a.out system.
   Copyright (C) 1990-2020 Free Software Foundation, Inc.

   This file is part of BFD, the Binary File Descriptor library.

   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 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "/usr/include/a.out.h"
#include <stdio.h>

#ifndef _
#define _(X) X
#endif

int
main (int argc, char** argv)
{
  struct exec my_exec;
  int page_size;
  char * target;
  char * arch = "unknown";
  FILE * file;

  target = argv[1];
  if (target == NULL)
    {
      fprintf (stderr, "Usage: gen-aout target_name\n");
      exit (1);
    }

  file = fopen ("gen-aout", "r");
  if (file == NULL)
    {
      fprintf (stderr, "Cannot open gen-aout!\n");
      return -1;
    }

  if (fread (&my_exec, sizeof (struct exec), 1, file) != 1)
    {
      fprintf(stderr, "Cannot read gen-aout!\n");
      return -1;
    }

  fclose (file);

#ifdef N_TXTOFF
  page_size = N_TXTOFF (&my_exec);
  if (page_size == 0)
    printf ("#define N_HEADER_IN_TEXT(x) 1\n");
  else
    printf ("#define N_HEADER_IN_TEXT(x) 0\n");
#endif

  printf("#define BYTES_IN_WORD %d\n", sizeof (int));
  if (my_exec.a_entry == 0)
    {
      printf ("#define ENTRY_CAN_BE_ZERO\n");
      printf ("#define N_SHARED_LIB(x) 0 /* Avoids warning */\n");
    }
  else
    {
      printf ("/*#define ENTRY_CAN_BE_ZERO*/\n");
      printf ("/*#define N_SHARED_LIB(x) 0*/\n");
    }

  printf ("#define TEXT_START_ADDR %d\n", my_exec.a_entry);

#ifdef PAGSIZ
  if (page_size == 0)
    page_size = PAGSIZ;
#endif

  if (page_size != 0)
    printf ("#define TARGET_PAGE_SIZE %d\n", page_size);
  else
    printf ("/* #define TARGET_PAGE_SIZE ??? */\n");

  printf ("#define SEGMENT_SIZE TARGET_PAGE_SIZE\n");

#ifdef vax
  arch = "vax";
#endif
  if (arch[0] == '1')
    {
      fprintf (stderr, _("warning: preprocessor substituted architecture name inside string;"));
      fprintf (stderr, _("         fix DEFAULT_ARCH in the output file yourself\n"));
      arch = "unknown";
    }
  printf ("#define DEFAULT_ARCH bfd_arch_%s\n\n", arch);

  printf ("/* Do not \"beautify\" the CONCAT* macro args.  Traditional C will not");
  printf ("   remove whitespace added here, and thus will fail to concatenate");
  printf ("   the tokens.  */");
  printf ("\n#define MY(OP) CONCAT2 (%s_,OP)\n\n", target);
  printf ("#define TARGETNAME \"a.out-%s\"\n\n", target);

  printf ("#include \"sysdep.h\"\n");
  printf ("#include \"bfd.h\"\n");
  printf ("#include \"libbfd.h\"\n");
  printf ("#include \"libaout.h\"\n");
  printf ("\n#include \"aout-target.h\"\n");

  return 0;
}