bfd/aout-encap.c

   1 /* BFD back-end for a.out files encapsulated with COFF headers.
   2    Copyright 1990, 1991, 1994, 1995, 2000 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 /* THIS MODULE IS NOT FINISHED.  IT PROBABLY DOESN'T EVEN COMPILE.  */
  21
  22 #if 0
  23 #define TARGET_PAGE_SIZE        4096
  24 #define SEGMENT_SIZE    TARGET_PAGE_SIZE
  25 #define TEXT_START_ADDR 0
  26 #define BYTES_IN_WORD 4
  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
  49   if (bfd_read ((PTR)magicbuf, 1, sizeof (magicbuf), abfd) !=
  50       sizeof (magicbuf))
  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 = bfd_h_get_16 (abfd, magicbuf);
  58   if (coff_magic != COFF_MAGIC)
  59     return 0;                   /* Not an encap coff file */
  60
  61   __header_offset_temp==COFF_MAGIC ? sizeof (struct coffheader) : 0)
  62   (fseek ((f), HEADER_OFFSET((f)), 1))
  63
  64   magic = bfd_h_get_32 (abfd, magicbuf);
  65
  66   if (N_BADMAG (*((struct internal_exec *) &magic))) return 0;
  67
  68   struct external_exec exec_bytes;
  69   if (bfd_read ((PTR) &exec_bytes, 1, EXEC_BYTES_SIZE, abfd)
  70       != EXEC_BYTES_SIZE) {
  71     if (bfd_get_error () != bfd_error_system_call)
  72       bfd_set_error (bfd_error_wrong_format);
  73     return 0;
  74   }
  75   NAME(aout,swap_exec_header_in) (abfd, &exec_bytes, &exec);
  76
  77   return aout_32_some_aout_object_p (abfd, &exec, encap_realcallback);
  78 }
  79
  80 /* Finish up the reading of a encapsulated-coff a.out file header */
  81 const bfd_target *
  82 encap_real_callback (abfd)
  83      bfd *abfd;
  84 {
  85   struct internal_exec *execp = exec_hdr (abfd);
  86
  87   MY(callback) (abfd, execp);
  88
  89   /* If we have a coff header, it can give us better values for
  90      text_start and exec_data_start.  This is particularly useful
  91      for remote debugging of embedded systems.  */
  92   if (N_FLAGS(exec_aouthdr) & N_FLAGS_COFF_ENCAPSULATE)
  93   {
  94           struct coffheader ch;
  95           int val;
  96           val = lseek (execchan, -(sizeof (AOUTHDR) + sizeof (ch)), 1);
  97           if (val == -1)
  98                   perror_with_name (filename);
  99           val = myread (execchan, &ch, sizeof (ch));
 100           if (val < 0)
 101                   perror_with_name (filename);
 102           text_start = ch.text_start;
 103           exec_data_start = ch.data_start;
 104   } else
 105          {
 106           text_start =
 107             IS_OBJECT_FILE (exec_aouthdr) ? 0 : N_TXTADDR (exec_aouthdr);
 108           exec_data_start = IS_OBJECT_FILE (exec_aouthdr)
 109             ? exec_aouthdr.a_text : N_DATADDR (exec_aouthdr);
 110   }
 111
 112   /* Determine the architecture and machine type of the object file.  */
 113   bfd_default_set_arch_mach(abfd, bfd_arch_m68k, 0); /* FIXME */
 114
 115   return abfd->xvec;
 116 }
 117
 118 /* Write an object file in Encapsulated COFF format.
 119    Section contents have already been written.  We write the
 120    file header, symbols, and relocation.  */
 121
 122 boolean
 123 encap_write_object_contents (abfd)
 124      bfd *abfd;
 125 {
 126   bfd_size_type data_pad = 0;
 127   struct external_exec exec_bytes;
 128   struct internal_exec *execp = exec_hdr (abfd);
 129
 130 /****** FIXME:  Fragments from the old GNU LD program for dealing with
 131         encap coff.  */
 132 struct coffheader coffheader;
 133 int need_coff_header;
 134
 135   /* Determine whether to count the header as part of
 136      the text size, and initialize the text size accordingly.
 137      This depends on the kind of system and on the output format selected.  */
 138
 139   N_SET_MAGIC (outheader, magic);
 140 #ifdef INITIALIZE_HEADER
 141   INITIALIZE_HEADER;
 142 #endif
 143
 144   text_size = sizeof (struct exec);
 145 #ifdef COFF_ENCAPSULATE
 146   if (relocatable_output == 0 && file_table[0].just_syms_flag == 0)
 147     {
 148       need_coff_header = 1;
 149       /* set this flag now, since it will change the values of N_TXTOFF, etc */
 150       N_SET_FLAGS (outheader, aout_backend_info (abfd)->exec_hdr_flags);
 151       text_size += sizeof (struct coffheader);
 152     }
 153 #endif
 154
 155 #ifdef COFF_ENCAPSULATE
 156   if (need_coff_header)
 157     {
 158       /* We are encapsulating BSD format within COFF format.  */
 159       struct coffscn *tp, *dp, *bp;
 160
 161       tp = &coffheader.scns[0];
 162       dp = &coffheader.scns[1];
 163       bp = &coffheader.scns[2];
 164
 165       strcpy (tp->s_name, ".text");
 166       tp->s_paddr = text_start;
 167       tp->s_vaddr = text_start;
 168       tp->s_size = text_size;
 169       tp->s_scnptr = sizeof (struct coffheader) + sizeof (struct exec);
 170       tp->s_relptr = 0;
 171       tp->s_lnnoptr = 0;
 172       tp->s_nreloc = 0;
 173       tp->s_nlnno = 0;
 174       tp->s_flags = 0x20;
 175       strcpy (dp->s_name, ".data");
 176       dp->s_paddr = data_start;
 177       dp->s_vaddr = data_start;
 178       dp->s_size = data_size;
 179       dp->s_scnptr = tp->s_scnptr + tp->s_size;
 180       dp->s_relptr = 0;
 181       dp->s_lnnoptr = 0;
 182       dp->s_nreloc = 0;
 183       dp->s_nlnno = 0;
 184       dp->s_flags = 0x40;
 185       strcpy (bp->s_name, ".bss");
 186       bp->s_paddr = dp->s_vaddr + dp->s_size;
 187       bp->s_vaddr = bp->s_paddr;
 188       bp->s_size = bss_size;
 189       bp->s_scnptr = 0;
 190       bp->s_relptr = 0;
 191       bp->s_lnnoptr = 0;
 192       bp->s_nreloc = 0;
 193       bp->s_nlnno = 0;
 194       bp->s_flags = 0x80;
 195
 196       coffheader.f_magic = COFF_MAGIC;
 197       coffheader.f_nscns = 3;
 198       /* store an unlikely time so programs can
 199        * tell that there is a bsd header
 200        */
 201       coffheader.f_timdat = 1;
 202       coffheader.f_symptr = 0;
 203       coffheader.f_nsyms = 0;
 204       coffheader.f_opthdr = 28;
 205       coffheader.f_flags = 0x103;
 206       /* aouthdr */
 207       coffheader.magic = ZMAGIC;
 208       coffheader.vstamp = 0;
 209       coffheader.tsize = tp->s_size;
 210       coffheader.dsize = dp->s_size;
 211       coffheader.bsize = bp->s_size;
 212       coffheader.entry = outheader.a_entry;
 213       coffheader.text_start = tp->s_vaddr;
 214       coffheader.data_start = dp->s_vaddr;
 215     }
 216 #endif
 217
 218 #ifdef COFF_ENCAPSULATE
 219   if (need_coff_header)
 220     mywrite (&coffheader, sizeof coffheader, 1, outdesc);
 221 #endif
 222
 223 #ifndef COFF_ENCAPSULATE
 224   padfile (N_TXTOFF (outheader) - sizeof outheader, outdesc);
 225 #endif
 226
 227   text_size -= N_TXTOFF (outheader);
 228   WRITE_HEADERS(abfd, execp);
 229   return true;
 230 }
 231
 232 #define MY_write_object_content encap_write_object_contents
 233 #define MY_object_p encap_object_p
 234 #define MY_exec_hdr_flags N_FLAGS_COFF_ENCAPSULATE
 235
 236 #include "aout-target.h"