bfd/aout-encap.c

   1 /* BFD back-end for a.out files encapsulated with COFF headers.
   2    Copyright 1990, 1991, 1994, 1995, 2000, 2001, 2002, 2003
   3    Free Software Foundation, Inc.
   4
   5 This file is part of BFD, the Binary File Descriptor library.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  20
  21 /* THIS MODULE IS NOT FINISHED.  IT PROBABLY DOESN'T EVEN COMPILE.  */
  22
  23 #if 0
  24 #define TARGET_PAGE_SIZE        4096
  25 #define SEGMENT_SIZE    TARGET_PAGE_SIZE
  26 #define TEXT_START_ADDR 0
  27 #endif
  28
  29 #include "bfd.h"
  30 #include "sysdep.h"
  31 #include "libbfd.h"
  32 #include "aout/aout64.h"
  33 #include "aout/stab_gnu.h"
  34 #include "aout/ar.h"
  35 #include "libaout.h"           /* BFD a.out internal data structures */
  36
  37 const bfd_target *encap_real_callback ();
  38
  39 const bfd_target *
  40 encap_object_p (abfd)
  41      bfd *abfd;
  42 {
  43   unsigned char magicbuf[4]; /* Raw bytes of magic number from file */
  44   unsigned long magic;          /* Swapped magic number */
  45   short coff_magic;
  46   struct external_exec exec_bytes;
  47   struct internal_exec exec;
  48   bfd_size_type amt = sizeof (magicbuf);
  49
  50   if (bfd_bread ((PTR) magicbuf, amt, abfd) != amt)
  51     {
  52       if (bfd_get_error () != bfd_error_system_call)
  53         bfd_set_error (bfd_error_wrong_format);
  54       return 0;
  55     }
  56
  57   coff_magic = H_GET_16 (abfd, magicbuf);
  58   if (coff_magic != COFF_MAGIC)
  59     return 0;                   /* Not an encap coff file */
  60
  61   magic = H_GET_32 (abfd, magicbuf);
  62
  63   if (N_BADMAG (*((struct internal_exec *) &magic)))
  64     return 0;
  65
  66   if (bfd_seek (abfd, (file_ptr) sizeof (struct coffheader), SEEK_SET) != 0)
  67     return 0;
  68
  69   amt = EXEC_BYTES_SIZE;
  70   if (bfd_bread ((PTR) &exec_bytes, amt, abfd) != amt)
  71     {
  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 an encapsulated-coff a.out file header.  */
  82 const 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     }
 106   else
 107     {
 108       text_start =
 109         IS_OBJECT_FILE (exec_aouthdr) ? 0 : N_TXTADDR (exec_aouthdr);
 110       exec_data_start = (IS_OBJECT_FILE (exec_aouthdr)
 111                          ? exec_aouthdr.a_text
 112                          : N_DATADDR (exec_aouthdr));
 113     }
 114
 115   /* Determine the architecture and machine type of the object file.  */
 116   bfd_default_set_arch_mach(abfd, bfd_arch_m68k, 0); /* FIXME */
 117
 118   return abfd->xvec;
 119 }
 120
 121 /* Write an object file in Encapsulated COFF format.
 122    Section contents have already been written.  We write the
 123    file header, symbols, and relocation.  */
 124
 125 bfd_boolean
 126 encap_write_object_contents (abfd)
 127      bfd *abfd;
 128 {
 129   bfd_size_type data_pad = 0;
 130   struct external_exec exec_bytes;
 131   struct internal_exec *execp = exec_hdr (abfd);
 132
 133   /* FIXME:  Fragments from the old GNU LD program for dealing with
 134      encap coff.  */
 135   struct coffheader coffheader;
 136   int need_coff_header;
 137
 138   /* Determine whether to count the header as part of
 139      the text size, and initialize the text size accordingly.
 140      This depends on the kind of system and on the output format selected.  */
 141
 142   N_SET_MAGIC (outheader, magic);
 143 #ifdef INITIALIZE_HEADER
 144   INITIALIZE_HEADER;
 145 #endif
 146
 147   text_size = sizeof (struct exec);
 148 #ifdef COFF_ENCAPSULATE
 149   if (relocatable_output == 0 && file_table[0].just_syms_flag == 0)
 150     {
 151       need_coff_header = 1;
 152       /* set this flag now, since it will change the values of N_TXTOFF, etc */
 153       N_SET_FLAGS (outheader, aout_backend_info (abfd)->exec_hdr_flags);
 154       text_size += sizeof (struct coffheader);
 155     }
 156 #endif
 157
 158 #ifdef COFF_ENCAPSULATE
 159   if (need_coff_header)
 160     {
 161       /* We are encapsulating BSD format within COFF format.  */
 162       struct coffscn *tp, *dp, *bp;
 163
 164       tp = &coffheader.scns[0];
 165       dp = &coffheader.scns[1];
 166       bp = &coffheader.scns[2];
 167
 168       strcpy (tp->s_name, ".text");
 169       tp->s_paddr = text_start;
 170       tp->s_vaddr = text_start;
 171       tp->s_size = text_size;
 172       tp->s_scnptr = sizeof (struct coffheader) + sizeof (struct exec);
 173       tp->s_relptr = 0;
 174       tp->s_lnnoptr = 0;
 175       tp->s_nreloc = 0;
 176       tp->s_nlnno = 0;
 177       tp->s_flags = 0x20;
 178       strcpy (dp->s_name, ".data");
 179       dp->s_paddr = data_start;
 180       dp->s_vaddr = data_start;
 181       dp->s_size = data_size;
 182       dp->s_scnptr = tp->s_scnptr + tp->s_size;
 183       dp->s_relptr = 0;
 184       dp->s_lnnoptr = 0;
 185       dp->s_nreloc = 0;
 186       dp->s_nlnno = 0;
 187       dp->s_flags = 0x40;
 188       strcpy (bp->s_name, ".bss");
 189       bp->s_paddr = dp->s_vaddr + dp->s_size;
 190       bp->s_vaddr = bp->s_paddr;
 191       bp->s_size = bss_size;
 192       bp->s_scnptr = 0;
 193       bp->s_relptr = 0;
 194       bp->s_lnnoptr = 0;
 195       bp->s_nreloc = 0;
 196       bp->s_nlnno = 0;
 197       bp->s_flags = 0x80;
 198
 199       coffheader.f_magic = COFF_MAGIC;
 200       coffheader.f_nscns = 3;
 201       /* store an unlikely time so programs can
 202        * tell that there is a bsd header
 203        */
 204       coffheader.f_timdat = 1;
 205       coffheader.f_symptr = 0;
 206       coffheader.f_nsyms = 0;
 207       coffheader.f_opthdr = 28;
 208       coffheader.f_flags = 0x103;
 209       /* aouthdr */
 210       coffheader.magic = ZMAGIC;
 211       coffheader.vstamp = 0;
 212       coffheader.tsize = tp->s_size;
 213       coffheader.dsize = dp->s_size;
 214       coffheader.bsize = bp->s_size;
 215       coffheader.entry = outheader.a_entry;
 216       coffheader.text_start = tp->s_vaddr;
 217       coffheader.data_start = dp->s_vaddr;
 218     }
 219 #endif
 220
 221 #ifdef COFF_ENCAPSULATE
 222   if (need_coff_header)
 223     mywrite (&coffheader, sizeof coffheader, 1, outdesc);
 224 #endif
 225
 226 #ifndef COFF_ENCAPSULATE
 227   padfile (N_TXTOFF (outheader) - sizeof outheader, outdesc);
 228 #endif
 229
 230   text_size -= N_TXTOFF (outheader);
 231   WRITE_HEADERS(abfd, execp);
 232   return TRUE;
 233 }
 234
 235 #define MY_write_object_content encap_write_object_contents
 236 #define MY_object_p encap_object_p
 237 #define MY_exec_hdr_flags N_FLAGS_COFF_ENCAPSULATE
 238
 239 #include "aout-target.h"