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/* Yet Another Try at encapsulating bsd object files in coff.

   Copyright 1988, 1989, 1991 Free Software Foundation, Inc.

   Written by Pace Willisson 12/9/88

   This file is obsolete.  It needs to be converted to just define a bunch

   of stuff that BFD can use to do coff-encapsulated files.  --gnu@cygnus.com

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.

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.  */

/*

 * We only use the coff headers to tell the kernel

 * how to exec the file.  Therefore, the only fields that need to

 * be filled in are the scnptr and vaddr for the text and data

 * sections, and the vaddr for the bss.  As far as coff is concerned,

 * there is no symbol table, relocation, or line numbers.

 *

 * A normal bsd header (struct exec) is placed after the coff headers,

 * and before the real text.  I defined a the new fields 'a_machtype'

 * and a_flags.  If a_machtype is M_386, and a_flags & A_ENCAP is

 * true, then the bsd header is preceeded by a coff header.  Macros

 * like N_TXTOFF and N_TXTADDR use this field to find the bsd header.

 *

 * The only problem is to track down the bsd exec header.  The

 * macros HEADER_OFFSET, etc do this.

 */

#define N_FLAGS_COFF_ENCAPSULATE 0x20 /* coff header precedes bsd header */

/* Describe the COFF header used for encapsulation.  */

struct coffheader

{

  /* filehdr */

  unsigned short f_magic;

  unsigned short f_nscns;

  long f_timdat;

  long f_symptr;

  long f_nsyms;

  unsigned short f_opthdr;

  unsigned short f_flags;

  /* aouthdr */

  short magic;

  short vstamp;

  long tsize;

  long dsize;

  long bsize;

  long entry;

  long text_start;

  long data_start;

  struct coffscn

    {

      char s_name[8];

      long s_paddr;

      long s_vaddr;

      long s_size;

      long s_scnptr;

      long s_relptr;

      long s_lnnoptr;

      unsigned short s_nreloc;

      unsigned short s_nlnno;

      long s_flags;

    } scns[3];

};

/* Describe some of the parameters of the encapsulation,

   including how to find the encapsulated BSD header.  */

/* FIXME, this is dumb.  The same tools can't handle a.outs for different

   architectures, just because COFF_MAGIC is different; so you need a

   separate GNU nm for every architecture!!?  Unfortunately, it needs to

   be this way, since the COFF_MAGIC value is determined by the kernel

   we're trying to fool here.  */

#define COFF_MAGIC_I386 0514 /* I386MAGIC */

#define COFF_MAGIC_M68K 0520 /* MC68MAGIC */

#ifdef COFF_MAGIC

short __header_offset_temp;

#define HEADER_OFFSET(f) \

        (__header_offset_temp = 0, \

         fread ((char *)&__header_offset_temp, sizeof (short), 1, (f)), \

         fseek ((f), -sizeof (short), 1), \

         __header_offset_temp==COFF_MAGIC ? sizeof(struct coffheader) : 0)

#else

#define HEADER_OFFSET(f) 0

#endif

#define HEADER_SEEK(f) (fseek ((f), HEADER_OFFSET((f)), 1))

/* Describe the characteristics of the BSD header

   that appears inside the encapsulation.  */

/* Encapsulated coff files that are linked ZMAGIC have a text segment

   offset just past the header (and a matching TXTADDR), excluding

   the headers from the text segment proper but keeping the physical

   layout and the virtual memory layout page-aligned.

   Non-encapsulated a.out files that are linked ZMAGIC have a text

   segment that starts at 0 and an N_TXTADR similarly offset to 0.

   They too are page-aligned with each other, but they include the

   a.out header as part of the text.

   The _N_HDROFF gets sizeof struct exec added to it, so we have

   to compensate here.  See <a.out.gnu.h>.  */

#undef _N_HDROFF

#undef N_TXTADDR

#undef N_DATADDR

#define _N_HDROFF(x) ((N_FLAGS(x) & N_FLAGS_COFF_ENCAPSULATE) ? \

                      sizeof (struct coffheader) : 0)

/* Address of text segment in memory after it is loaded.  */

#define N_TXTADDR(x) \

        ((N_FLAGS(x) & N_FLAGS_COFF_ENCAPSULATE) ? \

         sizeof (struct coffheader) + sizeof (struct exec) : 0)

#define SEGMENT_SIZE 0x400000

#define N_DATADDR(x) \

        ((N_FLAGS(x) & N_FLAGS_COFF_ENCAPSULATE) ? \

         (SEGMENT_SIZE + ((N_TXTADDR(x)+(x).a_text-1) & ~(SEGMENT_SIZE-1))) : \

         (N_TXTADDR(x)+(x).a_text))