bfd/coff-go32.c

   1 /* BFD back-end for Intel 386 COFF files (DJGPP variant).
   2    Copyright (C) 1990-2020 Free Software Foundation, Inc.
   3    Written by DJ Delorie.
   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 3 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., 51 Franklin Street - Fifth Floor, Boston,
  20    MA 02110-1301, USA.  */
  21
  22 #define TARGET_SYM              i386_coff_go32_vec
  23 #define TARGET_NAME             "coff-go32"
  24 #define TARGET_UNDERSCORE       '_'
  25 #define COFF_GO32
  26 #define COFF_LONG_SECTION_NAMES
  27 #define COFF_SUPPORT_GNU_LINKONCE
  28 #define COFF_LONG_FILENAMES
  29
  30 #define COFF_SECTION_ALIGNMENT_ENTRIES \
  31 { COFF_SECTION_NAME_EXACT_MATCH (".data"), \
  32   COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
  33 { COFF_SECTION_NAME_EXACT_MATCH (".text"), \
  34   COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
  35 { COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.d"), \
  36   COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
  37 { COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.t"), \
  38   COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
  39 { COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.r"), \
  40   COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
  41 { COFF_SECTION_NAME_PARTIAL_MATCH (".debug"), \
  42   COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 0 }, \
  43 { COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.wi"), \
  44   COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 0 }
  45
  46 /* Section contains extended relocations. */
  47 #define IMAGE_SCN_LNK_NRELOC_OVFL (0x01000000)
  48
  49 #include "sysdep.h"
  50 #include "bfd.h"
  51
  52 /* The following functions are not static, because they are also
  53    used for coff-go32-exe (coff-stgo32.c).  */
  54 bfd_boolean _bfd_go32_mkobject (bfd *);
  55 void _bfd_go32_swap_scnhdr_in (bfd *, void *, void *);
  56 unsigned int _bfd_go32_swap_scnhdr_out (bfd *, void *, void *);
  57
  58 #define coff_mkobject _bfd_go32_mkobject
  59 #define coff_SWAP_scnhdr_in _bfd_go32_swap_scnhdr_in
  60 #define coff_SWAP_scnhdr_out _bfd_go32_swap_scnhdr_out
  61
  62 #include "coff-i386.c"
  63
  64 bfd_boolean
  65 _bfd_go32_mkobject (bfd * abfd)
  66 {
  67   const bfd_size_type amt = sizeof (coff_data_type);
  68
  69   abfd->tdata.coff_obj_data = bfd_zalloc (abfd, amt);
  70   if (abfd->tdata.coff_obj_data == NULL)
  71     return FALSE;
  72
  73   coff_data (abfd)->go32 = TRUE;
  74
  75   return TRUE;
  76 }
  77
  78 void
  79 _bfd_go32_swap_scnhdr_in (bfd * abfd, void * ext, void * in)
  80 {
  81   SCNHDR *scnhdr_ext = (SCNHDR *) ext;
  82   struct internal_scnhdr *scnhdr_int = (struct internal_scnhdr *) in;
  83
  84   memcpy (scnhdr_int->s_name, scnhdr_ext->s_name, sizeof (scnhdr_int->s_name));
  85
  86   scnhdr_int->s_vaddr = GET_SCNHDR_VADDR (abfd, scnhdr_ext->s_vaddr);
  87   scnhdr_int->s_paddr = GET_SCNHDR_PADDR (abfd, scnhdr_ext->s_paddr);
  88   scnhdr_int->s_size = GET_SCNHDR_SIZE (abfd, scnhdr_ext->s_size);
  89
  90   scnhdr_int->s_scnptr = GET_SCNHDR_SCNPTR (abfd, scnhdr_ext->s_scnptr);
  91   scnhdr_int->s_relptr = GET_SCNHDR_RELPTR (abfd, scnhdr_ext->s_relptr);
  92   scnhdr_int->s_lnnoptr = GET_SCNHDR_LNNOPTR (abfd, scnhdr_ext->s_lnnoptr);
  93   scnhdr_int->s_flags = GET_SCNHDR_FLAGS (abfd, scnhdr_ext->s_flags);
  94   scnhdr_int->s_nreloc = GET_SCNHDR_NRELOC (abfd, scnhdr_ext->s_nreloc);
  95   scnhdr_int->s_nlnno = GET_SCNHDR_NLNNO (abfd, scnhdr_ext->s_nlnno);
  96
  97   /* DJGPP follows the same strategy as PE COFF.
  98      Iff the file is an executable then the higher 16 bits
  99      of the line number have been stored in the relocation
 100      counter field.  */
 101   if (abfd->flags & EXEC_P && (strcmp (scnhdr_ext->s_name, ".text") == 0))
 102     {
 103       scnhdr_int->s_nlnno
 104         = (GET_SCNHDR_NRELOC (abfd, scnhdr_ext->s_nreloc) << 16)
 105           + GET_SCNHDR_NLNNO (abfd, scnhdr_ext->s_nlnno);
 106       scnhdr_int->s_nreloc = 0;
 107     }
 108 }
 109
 110 unsigned int
 111 _bfd_go32_swap_scnhdr_out (bfd * abfd, void * in, void * out)
 112 {
 113   struct internal_scnhdr *scnhdr_int = (struct internal_scnhdr *) in;
 114   SCNHDR *scnhdr_ext = (SCNHDR *) out;
 115   unsigned int ret = bfd_coff_scnhsz (abfd);
 116
 117   memcpy (scnhdr_ext->s_name, scnhdr_int->s_name, sizeof (scnhdr_int->s_name));
 118
 119   PUT_SCNHDR_VADDR (abfd, scnhdr_int->s_vaddr, scnhdr_ext->s_vaddr);
 120   PUT_SCNHDR_PADDR (abfd, scnhdr_int->s_paddr, scnhdr_ext->s_paddr);
 121   PUT_SCNHDR_SIZE (abfd, scnhdr_int->s_size, scnhdr_ext->s_size);
 122   PUT_SCNHDR_SCNPTR (abfd, scnhdr_int->s_scnptr, scnhdr_ext->s_scnptr);
 123   PUT_SCNHDR_RELPTR (abfd, scnhdr_int->s_relptr, scnhdr_ext->s_relptr);
 124   PUT_SCNHDR_LNNOPTR (abfd, scnhdr_int->s_lnnoptr, scnhdr_ext->s_lnnoptr);
 125   PUT_SCNHDR_FLAGS (abfd, scnhdr_int->s_flags, scnhdr_ext->s_flags);
 126
 127   if (abfd->flags & EXEC_P && (strcmp (scnhdr_int->s_name, ".text") == 0))
 128     {
 129       /* DJGPP follows the same strategy as PE COFF.
 130          By inference from looking at MS output, the 32 bit field
 131          which is the combination of the number_of_relocs and
 132          number_of_linenos is used for the line number count in
 133          executables.  A 16-bit field won't do for cc1.  The MS
 134          document says that the number of relocs is zero for
 135          executables, but the 17-th bit has been observed to be there.
 136          Overflow is not an issue: a 4G-line program will overflow a
 137          bunch of other fields long before this!  */
 138       PUT_SCNHDR_NLNNO (abfd, (scnhdr_int->s_nlnno & 0xffff),
 139                         scnhdr_ext->s_nlnno);
 140       PUT_SCNHDR_NRELOC (abfd, (scnhdr_int->s_nlnno >> 16),
 141                          scnhdr_ext->s_nreloc);
 142     }
 143   else
 144     {
 145       /* DJGPP follows the same strategy as PE COFF.  */
 146       if (scnhdr_int->s_nlnno <= MAX_SCNHDR_NLNNO)
 147         PUT_SCNHDR_NLNNO (abfd, scnhdr_int->s_nlnno, scnhdr_ext->s_nlnno);
 148       else
 149         {
 150           char buf[sizeof (scnhdr_int->s_name) + 1];
 151
 152           memcpy (buf, scnhdr_int->s_name, sizeof (scnhdr_int->s_name));
 153           buf[sizeof (scnhdr_int->s_name)] = '\0';
 154           _bfd_error_handler
 155             /* xgettext:c-format */
 156             (_("%pB: warning: %s: line number overflow: 0x%lx > 0xffff"),
 157              abfd, buf, scnhdr_int->s_nlnno);
 158           bfd_set_error (bfd_error_file_truncated);
 159           PUT_SCNHDR_NLNNO (abfd, 0xffff, scnhdr_ext->s_nlnno);
 160           ret = 0;
 161         }
 162
 163       /* Although we could encode 0xffff relocs here, we do not, to be
 164          consistent with other parts of bfd.  Also it lets us warn, as
 165          we should never see 0xffff here w/o having the overflow flag
 166          set.  */
 167       if (scnhdr_int->s_nreloc < MAX_SCNHDR_NRELOC)
 168         PUT_SCNHDR_NRELOC (abfd, scnhdr_int->s_nreloc, scnhdr_ext->s_nreloc);
 169       else
 170         {
 171           /* DJGPP can deal with large #s of relocs, but not here.  */
 172           PUT_SCNHDR_NRELOC (abfd, 0xffff, scnhdr_ext->s_nreloc);
 173           scnhdr_int->s_flags |= IMAGE_SCN_LNK_NRELOC_OVFL;
 174           PUT_SCNHDR_FLAGS (abfd, scnhdr_int->s_flags, scnhdr_ext->s_flags);
 175         }
 176     }
 177
 178   return ret;
 179 }