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
   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 #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 const bfd_target *encap_real_callback ();
  39
  40 const 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   bfd_size_type amt = sizeof (magicbuf);
  50
  51   if (bfd_bread ((PTR) magicbuf, amt, abfd) != amt)
  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 = H_GET_16 (abfd, magicbuf);
  59   if (coff_magic != COFF_MAGIC)
  60     return 0;                   /* Not an encap coff file */
  61
  62   magic = H_GET_32 (abfd, magicbuf);
  63
  64   if (N_BADMAG (*((struct internal_exec *) &magic)))
  65     return 0;
  66
  67   if (bfd_seek (abfd, (file_ptr) sizeof (struct coffheader), SEEK_SET) != 0)
  68     return 0;
  69
  70   amt = EXEC_BYTES_SIZE;
  71   if (bfd_bread ((PTR) &exec_bytes, amt, abfd) != amt)
  72     {
  73       if (bfd_get_error () != bfd_error_system_call)
  74         bfd_set_error (bfd_error_wrong_format);
  75       return 0;
  76     }
  77   NAME(aout,swap_exec_header_in) (abfd, &exec_bytes, &exec);
  78
  79   return aout_32_some_aout_object_p (abfd, &exec, encap_realcallback);
  80 }
  81
  82 /* Finish up the reading of an encapsulated-coff a.out file header.  */
  83 const bfd_target *
  84 encap_real_callback (abfd)
  85      bfd *abfd;
  86 {
  87   struct internal_exec *execp = exec_hdr (abfd);
  88
  89   MY(callback) (abfd, execp);
  90
  91   /* If we have a coff header, it can give us better values for
  92      text_start and exec_data_start.  This is particularly useful
  93      for remote debugging of embedded systems.  */
  94   if (N_FLAGS(exec_aouthdr) & N_FLAGS_COFF_ENCAPSULATE)
  95     {
  96       struct coffheader ch;
  97       int val;
  98       val = lseek (execchan, -(sizeof (AOUTHDR) + sizeof (ch)), 1);
  99       if (val == -1)
 100         perror_with_name (filename);
 101       val = myread (execchan, &ch, sizeof (ch));
 102       if (val < 0)
 103         perror_with_name (filename);
 104       text_start = ch.text_start;
 105       exec_data_start = ch.data_start;
 106     }
 107   else
 108     {
 109       text_start =
 110         IS_OBJECT_FILE (exec_aouthdr) ? 0 : N_TXTADDR (exec_aouthdr);
 111       exec_data_start = (IS_OBJECT_FILE (exec_aouthdr)
 112                          ? exec_aouthdr.a_text
 113                          : N_DATADDR (exec_aouthdr));
 114     }
 115
 116   /* Determine the architecture and machine type of the object file.  */
 117   bfd_default_set_arch_mach(abfd, bfd_arch_m68k, 0); /* FIXME */
 118
 119   return abfd->xvec;
 120 }
 121
 122 /* Write an object file in Encapsulated COFF format.
 123    Section contents have already been written.  We write the
 124    file header, symbols, and relocation.  */
 125
 126 bfd_boolean
 127 encap_write_object_contents (abfd)
 128      bfd *abfd;
 129 {
 130   bfd_size_type data_pad = 0;
 131   struct external_exec exec_bytes;
 132   struct internal_exec *execp = exec_hdr (abfd);
 133
 134   /* FIXME:  Fragments from the old GNU LD program for dealing with
 135      encap coff.  */
 136   struct coffheader coffheader;
 137   int need_coff_header;
 138
 139   /* Determine whether to count the header as part of
 140      the text size, and initialize the text size accordingly.
 141      This depends on the kind of system and on the output format selected.  */
 142
 143   N_SET_MAGIC (outheader, magic);
 144 #ifdef INITIALIZE_HEADER
 145   INITIALIZE_HEADER;
 146 #endif
 147
 148   text_size = sizeof (struct exec);
 149 #ifdef COFF_ENCAPSULATE
 150   if (relocatable_output == 0 && file_table[0].just_syms_flag == 0)
 151     {
 152       need_coff_header = 1;
 153       /* set this flag now, since it will change the values of N_TXTOFF, etc */
 154       N_SET_FLAGS (outheader, aout_backend_info (abfd)->exec_hdr_flags);
 155       text_size += sizeof (struct coffheader);
 156     }
 157 #endif
 158
 159 #ifdef COFF_ENCAPSULATE
 160   if (need_coff_header)
 161     {
 162       /* We are encapsulating BSD format within COFF format.  */
 163       struct coffscn *tp, *dp, *bp;
 164
 165       tp = &coffheader.scns[0];
 166       dp = &coffheader.scns[1];
 167       bp = &coffheader.scns[2];
 168
 169       strcpy (tp->s_name, ".text");
 170       tp->s_paddr = text_start;
 171       tp->s_vaddr = text_start;
 172       tp->s_size = text_size;
 173       tp->s_scnptr = sizeof (struct coffheader) + sizeof (struct exec);
 174       tp->s_relptr = 0;
 175       tp->s_lnnoptr = 0;
 176       tp->s_nreloc = 0;
 177       tp->s_nlnno = 0;
 178       tp->s_flags = 0x20;
 179       strcpy (dp->s_name, ".data");
 180       dp->s_paddr = data_start;
 181       dp->s_vaddr = data_start;
 182       dp->s_size = data_size;
 183       dp->s_scnptr = tp->s_scnptr + tp->s_size;
 184       dp->s_relptr = 0;
 185       dp->s_lnnoptr = 0;
 186       dp->s_nreloc = 0;
 187       dp->s_nlnno = 0;
 188       dp->s_flags = 0x40;
 189       strcpy (bp->s_name, ".bss");
 190       bp->s_paddr = dp->s_vaddr + dp->s_size;
 191       bp->s_vaddr = bp->s_paddr;
 192       bp->s_size = bss_size;
 193       bp->s_scnptr = 0;
 194       bp->s_relptr = 0;
 195       bp->s_lnnoptr = 0;
 196       bp->s_nreloc = 0;
 197       bp->s_nlnno = 0;
 198       bp->s_flags = 0x80;
 199
 200       coffheader.f_magic = COFF_MAGIC;
 201       coffheader.f_nscns = 3;
 202       /* store an unlikely time so programs can
 203        * tell that there is a bsd header
 204        */
 205       coffheader.f_timdat = 1;
 206       coffheader.f_symptr = 0;
 207       coffheader.f_nsyms = 0;
 208       coffheader.f_opthdr = 28;
 209       coffheader.f_flags = 0x103;
 210       /* aouthdr */
 211       coffheader.magic = ZMAGIC;
 212       coffheader.vstamp = 0;
 213       coffheader.tsize = tp->s_size;
 214       coffheader.dsize = dp->s_size;
 215       coffheader.bsize = bp->s_size;
 216       coffheader.entry = outheader.a_entry;
 217       coffheader.text_start = tp->s_vaddr;
 218       coffheader.data_start = dp->s_vaddr;
 219     }
 220 #endif
 221
 222 #ifdef COFF_ENCAPSULATE
 223   if (need_coff_header)
 224     mywrite (&coffheader, sizeof coffheader, 1, outdesc);
 225 #endif
 226
 227 #ifndef COFF_ENCAPSULATE
 228   padfile (N_TXTOFF (outheader) - sizeof outheader, outdesc);
 229 #endif
 230
 231   text_size -= N_TXTOFF (outheader);
 232   WRITE_HEADERS(abfd, execp);
 233   return TRUE;
 234 }
 235
 236 #define MY_write_object_content encap_write_object_contents
 237 #define MY_object_p encap_object_p
 238 #define MY_exec_hdr_flags N_FLAGS_COFF_ENCAPSULATE
 239
 240 #include "aout-target.h"