versados.c

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/* BFD back-end for VERSAdos-E objects.
   Copyright 1995, 1996, 1998, 1999, 2000 Free Software Foundation, Inc.
   Written by Steve Chamberlain of Cygnus Support <[e-mail]>.

   Versados is a Motorola trademark.

   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 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/*
   SUBSECTION
   VERSAdos-E relocateable object file format

   DESCRIPTION

   This module supports reading of VERSAdos relocateable
   object files.

   A VERSAdos file looks like contains

   o Indentification Record
   o External Symbol Definition Record
   o Object Text Recrod
   o End Record

 */

#include "bfd.h"
#include "sysdep.h"
#include "libbfd.h"
#include "libiberty.h"

static boolean versados_mkobject PARAMS ((bfd *));
static boolean versados_scan PARAMS ((bfd *));
static const bfd_target *versados_object_p PARAMS ((bfd *));

#define VHEADER '1'
#define VESTDEF '2'
#define VOTR '3'
#define VEND '4'

#define ES_BASE 17		/* first symbol has esdid 17 */

/* Per file target dependent information */

/* one for each section */
struct esdid
  {
    asection *section;		/* ptr to bfd version */
    unsigned char *contents;	/* used to build image */
    int pc;
    int relocs;			/* reloc count, valid end of pass 1 */
    int donerel;		/* have relocs been translated */
  };

typedef struct versados_data_struct
  {
    int es_done;		/* count of symbol index, starts at ES_BASE */
    asymbol *symbols;		/* pointer to local symbols */
    char *strings;		/* strings of all the above */
    int stringlen;		/* len of string table (valid end of pass1) */
    int nsecsyms;		/* number of sections */

    int ndefs;			/* number of exported symbols (they dont get esdids) */
    int nrefs;			/* number of imported symbols  (valid end of pass1) */

    int ref_idx;		/* current processed value of the above */
    int def_idx;

    int pass_2_done;

    struct esdid e[16];		/* per section info */
    int alert;			/* to see if we're trampling */
    asymbol *rest[256 - 16];	/* per symbol info */

  }
tdata_type;

#define VDATA(abfd)       (abfd->tdata.versados_data)
#define EDATA(abfd, n)    (abfd->tdata.versados_data->e[n])
#define RDATA(abfd, n)    (abfd->tdata.versados_data->rest[n])

struct ext_otr
  {
    unsigned char size;
    char type;
    unsigned char map[4];
    unsigned char esdid;
    unsigned char data[200];
  };

struct ext_vheader
  {
    unsigned char size;
    char type;			/* record type */
    char name[10];		/* module name */
    char rev;			/* module rev number */
    char lang;
    char vol[4];
    char user[2];
    char cat[8];
    char fname[8];
    char ext[2];
    char time[3];
    char date[3];
    char rest[211];
  };

struct ext_esd
  {
    unsigned char size;
    char type;
    unsigned char esd_entries[1];
  };
#define ESD_ABS 	0
#define ESD_COMMON 	1
#define ESD_STD_REL_SEC 2
#define ESD_SHRT_REL_SEC 3
#define ESD_XDEF_IN_SEC 4
#define ESD_XREF_SYM    7
#define ESD_XREF_SEC	6
#define ESD_XDEF_IN_ABS 5
union ext_any
  {
    unsigned char size;
    struct ext_vheader header;
    struct ext_esd esd;
    struct ext_otr otr;
  };

/* Initialize by filling in the hex conversion array.  */

/* Set up the tdata information.  */

static boolean
versados_mkobject (abfd)
     bfd *abfd;
{
  if (abfd->tdata.versados_data == NULL)
    {
      tdata_type *tdata = (tdata_type *) bfd_alloc (abfd, sizeof (tdata_type));
      if (tdata == NULL)
	return false;
      abfd->tdata.versados_data = tdata;
      tdata->symbols = NULL;
      VDATA (abfd)->alert = 0x12345678;
    }

  bfd_default_set_arch_mach (abfd, bfd_arch_m68k, 0);
  return true;
}

/* Report a problem in an S record file.  FIXME: This probably should
   not call fprintf, but we really do need some mechanism for printing
   error messages.  */

static asymbol *
versados_new_symbol (abfd, snum, name, val, sec)
     bfd *abfd;
     int snum;
     const char *name;
     bfd_vma val;
     asection *sec;
{
  asymbol *n = VDATA (abfd)->symbols + snum;
  n->name = name;
  n->value = val;
  n->section = sec;
  n->the_bfd = abfd;
  n->flags = 0;
  return n;
}

static int
get_record (abfd, ptr)
     bfd *abfd;
     union ext_any *ptr;
{
  bfd_read (&ptr->size, 1, 1, abfd);
  if (bfd_read ((char *) ptr + 1, 1, ptr->size, abfd) != ptr->size)
    return 0;
  return 1;
}

int
get_4 (pp)
     unsigned char **pp;
{
  unsigned char *p = *pp;
  *pp += 4;
  return (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | (p[3] << 0);
}

void
get_10 (pp, name)
     unsigned char **pp;
     char *name;
{
  char *p = (char *) *pp;
  int len = 10;
  *pp += len;
  while (*p != ' '
	 && len)
    {
      *name++ = *p++;
      len--;
    }
  *name = 0;
}

static char *
new_symbol_string (abfd, name)
     bfd *abfd;
     char *name;
{
  char *n = VDATA (abfd)->strings;
  strcpy (VDATA (abfd)->strings, name);
  VDATA (abfd)->strings += strlen (VDATA (abfd)->strings) + 1;
  return n;
}

static void
process_esd (abfd, esd, pass)
     bfd *abfd;
     struct ext_esd *esd;
     int pass;
{
  /* Read through the ext def for the est entries */
  int togo = esd->size - 2;
  bfd_vma size;
  bfd_vma start;
  asection *sec;
  char name[11];
  unsigned char *ptr = esd->esd_entries;
  unsigned char *end = ptr + togo;
  while (ptr < end)
    {
      int scn = *ptr & 0xf;
      int typ = (*ptr >> 4) & 0xf;

      /* Declare this section */
      sprintf (name, "%d", scn);
      sec = bfd_make_section_old_way (abfd, strdup (name));
      sec->target_index = scn;
      EDATA (abfd, scn).section = sec;
      ptr++;
      switch (typ)
	{
	default:
	  abort ();
	case ESD_XREF_SEC:
	case ESD_XREF_SYM:
	  {
	    int snum = VDATA (abfd)->ref_idx++;
	    get_10 (&ptr, name);
	    if (pass == 1)
	      {
		VDATA (abfd)->stringlen += strlen (name) + 1;
	      }
	    else
	      {
		int esidx;
		asymbol *s;
		char *n = new_symbol_string (abfd, name);
		s = versados_new_symbol (abfd, snum, n, 0,
					 &bfd_und_section, scn);
		esidx = VDATA (abfd)->es_done++;
		RDATA (abfd, esidx - ES_BASE) = s;
	      }
	  }
	  break;

	case ESD_ABS:
	  size = get_4 (&ptr);
	  start = get_4 (&ptr);
	  break;
	case ESD_STD_REL_SEC:
	case ESD_SHRT_REL_SEC:
	  {
	    sec->_raw_size = get_4 (&ptr);
	    sec->flags |= SEC_ALLOC;
	  }
	  break;
	case ESD_XDEF_IN_ABS:
	  sec = (asection *) & bfd_abs_section;
	case ESD_XDEF_IN_SEC:
	  {
	    int snum = VDATA (abfd)->def_idx++;
	    long val;
	    get_10 (&ptr, name);
	    val = get_4 (&ptr);
	    if (pass == 1)
	      {
		/* Just remember the symbol */
		VDATA (abfd)->stringlen += strlen (name) + 1;
	      }
	    else
	      {
		asymbol *s;
		char *n = new_symbol_string (abfd, name);
		s = versados_new_symbol (abfd, snum + VDATA (abfd)->nrefs, n, val, sec, scn);
		s->flags |= BSF_GLOBAL;
	      }
	  }
	  break;
	}
    }
}

#define R_RELWORD 1
#define R_RELLONG 2
#define R_RELWORD_NEG 3
#define R_RELLONG_NEG 4

reloc_howto_type versados_howto_table[] =
{
  HOWTO (R_RELWORD, 0, 1, 16, false,
	 0, complain_overflow_dont, 0,
	 "+v16", true, 0x0000ffff, 0x0000ffff, false),
  HOWTO (R_RELLONG, 0, 2, 32, false,
	 0, complain_overflow_dont, 0,
	 "+v32", true, 0xffffffff, 0xffffffff, false),

  HOWTO (R_RELWORD_NEG, 0, -1, 16, false,
	 0, complain_overflow_dont, 0,
	 "-v16", true, 0x0000ffff, 0x0000ffff, false),
  HOWTO (R_RELLONG_NEG, 0, -2, 32, false,
	 0, complain_overflow_dont, 0,
	 "-v32", true, 0xffffffff, 0xffffffff, false),
};

static int
get_offset (len, ptr)
     int len;
     unsigned char *ptr;
{
  int val = 0;
  if (len)
    {
      int i;
      val = *ptr++;
      if (val & 0x80)
	val |= ~0xff;
      for (i = 1; i < len; i++)
	val = (val << 8) | *ptr++;
    }

  return val;
}

static void
process_otr (abfd, otr, pass)
     bfd *abfd;
     struct ext_otr *otr;
     int pass;
{
  unsigned long shift;
  unsigned char *srcp = otr->data;
  unsigned char *endp = (unsigned char *) otr + otr->size;
  unsigned int bits = (otr->map[0] << 24)
  | (otr->map[1] << 16)
  | (otr->map[2] << 8)
  | (otr->map[3] << 0);

  struct esdid *esdid = &EDATA (abfd, otr->esdid - 1);
  unsigned char *contents = esdid->contents;
  int need_contents = 0;
  unsigned int dst_idx = esdid->pc;

  for (shift = (1 << 31); shift && srcp < endp; shift >>= 1)
    {
      if (bits & shift)
	{
	  int flag = *srcp++;
	  int esdids = (flag >> 5) & 0x7;
	  int sizeinwords = ((flag >> 3) & 1) ? 2 : 1;
	  int offsetlen = flag & 0x7;
	  int j;

	  if (esdids == 0)
	    {
	      /* A zero esdid means the new pc is the offset given */
	      dst_idx += get_offset (offsetlen, srcp);
	      srcp += offsetlen;
	    }
	  else
	    {
	      int val = get_offset (offsetlen, srcp + esdids);
	      if (pass == 1)
		need_contents = 1;
	      else
		for (j = 0; j < sizeinwords * 2; j++)
		  {
		    contents[dst_idx + (sizeinwords * 2) - j - 1] = val;
		    val >>= 8;
		  }

	      for (j = 0; j < esdids; j++)
		{
		  int esdid = *srcp++;

		  if (esdid)
		    {
		      int rn = EDATA (abfd, otr->esdid - 1).relocs++;
		      if (pass == 1)
			{
			  /* this is the first pass over the data,
			     just remember that we need a reloc */
			}
		      else
			{
			  arelent *n =
			  EDATA (abfd, otr->esdid - 1).section->relocation + rn;
			  n->address = dst_idx;

			  n->sym_ptr_ptr = (asymbol **) esdid;
			  n->addend = 0;
			  n->howto = versados_howto_table + ((j & 1) * 2) + (sizeinwords - 1);
			}
		    }
		}
	      srcp += offsetlen;
	      dst_idx += sizeinwords * 2;
	    }
	}
      else
	{
	  need_contents = 1;
	  if (dst_idx < esdid->section->_raw_size)
	    if (pass == 2)
	      {
		/* absolute code, comes in 16 bit lumps */
		contents[dst_idx] = srcp[0];
		contents[dst_idx + 1] = srcp[1];
	      }
	  dst_idx += 2;
	  srcp += 2;
	}