bfd/aout-encap.c

   1 /* BFD back-end for a.out files encapsulated with COFF headers.
   2    Copyright (C) 1990, 1991 Free Software Foundation, Inc.
   3
   4 This file is part of BFD, the Binary File Descriptor library.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 /* THIS MODULE IS NOT FINISHED.  IT PROBABLY DOESN'T EVEN COMPILE.  */
  21
  22 #if 0
  23 #define PAGE_SIZE       4096
  24 #define SEGMENT_SIZE    PAGE_SIZE
  25 #define TEXT_START_ADDR 0
  26 #define ARCH 32
  27 #define BYTES_IN_WORD 4
  28 #endif
  29
  30 #include "bfd.h"
  31 #include <sysdep.h>
  32 #include "libbfd.h"
  33 #include <aout/aout64.h>
  34 #include "aout/stab_gnu.h"
  35 #include "aout/ar.h"
  36 #include "libaout.h"           /* BFD a.out internal data structures */
  37
  38 bfd_target *encap_real_callback ();
  39
  40 bfd_target *
  41 encap_object_p (abfd)
  42      bfd *abfd;
  43 {
  44   unsigned char magicbuf[4]; /* Raw bytes of magic number from file */
  45   unsigned long magic;          /* Swapped magic number */
  46   short coff_magic;
  47   struct external_exec exec_bytes;
  48   struct internal_exec exec;
  49
  50   if (bfd_read ((PTR)magicbuf, 1, sizeof (magicbuf), abfd) !=
  51       sizeof (magicbuf))
  52     {
  53       if (bfd_get_error () != bfd_error_system_call)
  54         bfd_set_error (bfd_error_wrong_format);
  55       return 0;
  56     }
  57
  58   coff_magic = bfd_h_get_16 (abfd, magicbuf);
  59   if (coff_magic != COFF_MAGIC)
  60     return 0;                   /* Not an encap coff file */
  61
  62   __header_offset_temp==COFF_MAGIC ? sizeof(struct coffheader) : 0)
  63   (fseek ((f), HEADER_OFFSET((f)), 1))
  64
  65   magic = bfd_h_get_32 (abfd, magicbuf);
  66
  67   if (N_BADMAG (*((struct internal_exec *) &magic))) return 0;
  68
  69   struct external_exec exec_bytes;
  70   if (bfd_read ((PTR) &exec_bytes, 1, EXEC_BYTES_SIZE, abfd)
  71       != EXEC_BYTES_SIZE) {
  72     if (bfd_get_error () != bfd_error_system_call)
  73       bfd_set_error (bfd_error_wrong_format);
  74     return 0;
  75   }
  76   NAME(aout,swap_exec_header_in)(abfd, &exec_bytes, &exec);
  77
  78   return aout_32_some_aout_object_p (abfd, &exec, encap_realcallback);
  79 }
  80
  81 /* Finish up the reading of a encapsulated-coff a.out file header */
  82 bfd_target *
  83 encap_real_callback (abfd)
  84      bfd *abfd;
  85 {
  86   struct internal_exec *execp = exec_hdr (abfd);
  87
  88   MY(callback)(abfd, execp);
  89
  90   /* If we have a coff header, it can give us better values for
  91      text_start and exec_data_start.  This is particularly useful
  92      for remote debugging of embedded systems.  */
  93   if (N_FLAGS(exec_aouthdr) & N_FLAGS_COFF_ENCAPSULATE)
  94   {
  95           struct coffheader ch;
  96           int val;
  97           val = lseek (execchan, -(sizeof (AOUTHDR) + sizeof (ch)), 1);
  98           if (val == -1)
  99                   perror_with_name (filename);
 100           val = myread (execchan, &ch, sizeof (ch));
 101           if (val < 0)
 102                   perror_with_name (filename);
 103           text_start = ch.text_start;
 104           exec_data_start = ch.data_start;
 105   } else
 106          {
 107           text_start =
 108             IS_OBJECT_FILE (exec_aouthdr) ? 0 : N_TXTADDR (exec_aouthdr);
 109           exec_data_start = IS_OBJECT_FILE (exec_aouthdr)
 110             ? exec_aouthdr.a_text : N_DATADDR (exec_aouthdr);
 111   }
 112
 113   /* Determine the architecture and machine type of the object file.  */
 114   bfd_default_set_arch_mach(abfd, bfd_arch_m68k, 0); /* FIXME */
 115
 116   return abfd->xvec;
 117 }
 118
 119 /* Write an object file in Encapsulated COFF format.
 120    Section contents have already been written.  We write the
 121    file header, symbols, and relocation.  */
 122
 123 boolean
 124 encap_write_object_contents (abfd)
 125      bfd *abfd;
 126 {
 127   bfd_size_type data_pad = 0;
 128   struct external_exec exec_bytes;
 129   struct internal_exec *execp = exec_hdr (abfd);
 130
 131 /****** FIXME:  Fragments from the old GNU LD program for dealing with
 132         encap coff.  */
 133 struct coffheader coffheader;
 134 int need_coff_header;
 135
 136   /* Determine whether to count the header as part of
 137      the text size, and initialize the text size accordingly.
 138      This depends on the kind of system and on the output format selected.  */
 139
 140   N_SET_MAGIC (outheader, magic);
 141 #ifdef INITIALIZE_HEADER
 142   INITIALIZE_HEADER;
 143 #endif
 144
 145   text_size = sizeof (struct exec);
 146 #ifdef COFF_ENCAPSULATE
 147   if (relocatable_output == 0 && file_table[0].just_syms_flag == 0)
 148     {
 149       need_coff_header = 1;
 150       /* set this flag now, since it will change the values of N_TXTOFF, etc */
 151       N_SET_FLAGS (outheader, aout_backend_info (abfd)->exec_hdr_flags);
 152       text_size += sizeof (struct coffheader);
 153     }
 154 #endif
 155
 156 #ifdef COFF_ENCAPSULATE
 157   if (need_coff_header)
 158     {
 159       /* We are encapsulating BSD format within COFF format.  */
 160       struct coffscn *tp, *dp, *bp;
 161
 162       tp = &coffheader.scns[0];
 163       dp = &coffheader.scns[1];
 164       bp = &coffheader.scns[2];
 165
 166       strcpy (tp->s_name, ".text");
 167       tp->s_paddr = text_start;
 168       tp->s_vaddr = text_start;
 169       tp->s_size = text_size;
 170       tp->s_scnptr = sizeof (struct coffheader) + sizeof (struct exec);
 171       tp->s_relptr = 0;
 172       tp->s_lnnoptr = 0;
 173       tp->s_nreloc = 0;
 174       tp->s_nlnno = 0;
 175       tp->s_flags = 0x20;
 176       strcpy (dp->s_name, ".data");
 177       dp->s_paddr = data_start;
 178       dp->s_vaddr = data_start;
 179       dp->s_size = data_size;
 180       dp->s_scnptr = tp->s_scnptr + tp->s_size;
 181       dp->s_relptr = 0;
 182       dp->s_lnnoptr = 0;
 183       dp->s_nreloc = 0;
 184       dp->s_nlnno = 0;
 185       dp->s_flags = 0x40;
 186       strcpy (bp->s_name, ".bss");
 187       bp->s_paddr = dp->s_vaddr + dp->s_size;
 188       bp->s_vaddr = bp->s_paddr;
 189       bp->s_size = bss_size;
 190       bp->s_scnptr = 0;
 191       bp->s_relptr = 0;
 192       bp->s_lnnoptr = 0;
 193       bp->s_nreloc = 0;
 194       bp->s_nlnno = 0;
 195       bp->s_flags = 0x80;
 196
 197       coffheader.f_magic = COFF_MAGIC;
 198       coffheader.f_nscns = 3;
 199       /* store an unlikely time so programs can
 200        * tell that there is a bsd header
 201        */
 202       coffheader.f_timdat = 1;
 203       coffheader.f_symptr = 0;
 204       coffheader.f_nsyms = 0;
 205       coffheader.f_opthdr = 28;
 206       coffheader.f_flags = 0x103;
 207       /* aouthdr */
 208       coffheader.magic = ZMAGIC;
 209       coffheader.vstamp = 0;
 210       coffheader.tsize = tp->s_size;
 211       coffheader.dsize = dp->s_size;
 212       coffheader.bsize = bp->s_size;
 213       coffheader.entry = outheader.a_entry;
 214       coffheader.text_start = tp->s_vaddr;
 215       coffheader.data_start = dp->s_vaddr;
 216     }
 217 #endif
 218
 219 #ifdef COFF_ENCAPSULATE
 220   if (need_coff_header)
 221     mywrite (&coffheader, sizeof coffheader, 1, outdesc);
 222 #endif
 223
 224 #ifndef COFF_ENCAPSULATE
 225   padfile (N_TXTOFF (outheader) - sizeof outheader, outdesc);
 226 #endif
 227
 228   text_size -= N_TXTOFF (outheader);
 229   WRITE_HEADERS(abfd, execp);
 230   return true;
 231 }
 232
 233 #define MY_write_object_content encap_write_object_contents
 234 #define MY_object_p encap_object_p
 235 #define MY_exec_hdr_flags N_FLAGS_COFF_ENCAPSULATE
 236
 237 #include "aout-target.h"