bfd/seclet.c

   1 /* seclet.c
   2    Copyright (C) 1992, 1993 Free Software Foundation, Inc.
   3    Written by Cygnus Support.
   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., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 /* This module is part of BFD */
  22
  23
  24 /* The intention is that one day, all the code which uses sections
  25    will change and use seclets instead - maybe seglet would have been
  26    a better name..
  27
  28    Anyway, a seclet contains enough info to be able to describe an
  29    area of output memory in one go.
  30
  31    The only description so far catered for is that of the
  32    <<bfd_indirect_seclet>>, which is a select which points to a
  33    <<section>> and the <<asymbols>> associated with the section, so
  34    that relocation can be done when needed.
  35
  36    One day there will be more types - they will at least migrate from
  37    the linker's data structures - also there could be extra stuff,
  38    like a bss seclet, which descibes a lump of memory as containing
  39    zeros compactly, without the horrible SEC_* flag cruft.
  40
  41
  42 */
  43
  44 #include "bfd.h"
  45 #include "sysdep.h"
  46 #include "libbfd.h"
  47 #include "seclet.h"
  48 #include "coff/internal.h"
  49
  50 /* Create a new seclet and attach it to a section.  */
  51
  52 bfd_seclet_type *
  53 DEFUN(bfd_new_seclet,(abfd, section),
  54       bfd *abfd AND
  55       asection *section)
  56 {
  57   bfd_seclet_type *n = (bfd_seclet_type *)bfd_alloc(abfd, sizeof(bfd_seclet_type));
  58   if (section->seclets_tail != (bfd_seclet_type *)NULL) {
  59       section->seclets_tail->next = n;
  60     }
  61   else
  62   {
  63     section->seclets_head = n;
  64   }
  65   section->seclets_tail = n;
  66
  67   return n;
  68 }
  69
  70 /* Given an indirect seclet which points to an input section, relocate
  71    the contents of the seclet and put the data in its final
  72    destination.  */
  73
  74 static boolean
  75 DEFUN(rel,(abfd, seclet, output_section, data, relocateable),
  76       bfd *abfd AND
  77       bfd_seclet_type *seclet AND
  78       asection *output_section AND
  79       PTR data AND
  80       boolean relocateable)
  81 {
  82
  83   if (output_section->flags & SEC_HAS_CONTENTS
  84       && !(output_section->flags & SEC_NEVER_LOAD)
  85       && (output_section->flags & SEC_LOAD)
  86       && seclet->size)
  87   {
  88     data = (PTR) bfd_get_relocated_section_contents(abfd, seclet, data,
  89                                                     relocateable);
  90     if(bfd_set_section_contents(abfd,
  91                                 output_section,
  92                                 data,
  93                                 seclet->offset,
  94                                 seclet->size) == false)
  95     {
  96       abort();
  97     }
  98   }
  99   return true;
 100 }
 101
 102 /* Put the contents of a seclet in its final destination.  */
 103
 104 static boolean
 105 DEFUN(seclet_dump_seclet,(abfd, seclet, section, data, relocateable),
 106       bfd *abfd AND
 107       bfd_seclet_type *seclet AND
 108       asection *section AND
 109       PTR data AND
 110       boolean relocateable)
 111 {
 112   switch (seclet->type)
 113     {
 114     case bfd_indirect_seclet:
 115       /* The contents of this section come from another one somewhere
 116          else */
 117       return rel(abfd, seclet, section, data, relocateable);
 118
 119     case bfd_fill_seclet:
 120       /* Fill in the section with us */
 121       {
 122         char *d = bfd_xmalloc(seclet->size);
 123         unsigned int i;
 124         for (i =0;  i < seclet->size; i+=2) {
 125           d[i] = seclet->u.fill.value >> 8;
 126         }
 127         for (i = 1; i < seclet->size; i+=2) {
 128           d[i] = seclet->u.fill.value ;
 129         }
 130         /* Don't bother to fill in empty sections */
 131         if (!bfd_get_section_flags(abfd, section) & SEC_HAS_CONTENTS)
 132           {
 133             return true;
 134           }
 135         return bfd_set_section_contents(abfd, section, d, seclet->offset,
 136                                         seclet->size);
 137       }
 138
 139     default:
 140       abort();
 141     }
 142
 143   return true;
 144 }
 145
 146 /*
 147 INTERNAL_FUNCTION
 148         bfd_generic_seclet_link
 149
 150 SYNOPSIS
 151         boolean bfd_generic_seclet_link
 152          (bfd *abfd,
 153           PTR data,
 154           boolean relocateable);
 155
 156 DESCRIPTION
 157
 158         The generic seclet linking routine.  The caller should have
 159         set up seclets for all the output sections.  The DATA argument
 160         should point to a memory area large enough to hold the largest
 161         section.  This function looks through the seclets and moves
 162         the contents into the output sections.  If RELOCATEABLE is
 163         true, the orelocation fields of the output sections must
 164         already be initialized.
 165
 166 */
 167
 168 boolean
 169 DEFUN(bfd_generic_seclet_link,(abfd, data, relocateable),
 170       bfd *abfd AND
 171       PTR data AND
 172       boolean relocateable)
 173 {
 174   asection *o = abfd->sections;
 175   while (o != (asection *)NULL)
 176   {
 177     bfd_seclet_type *p = o->seclets_head;
 178     while (p != (bfd_seclet_type *)NULL)
 179     {
 180       if (seclet_dump_seclet(abfd, p, o, data, relocateable) == false)
 181         return false;
 182       p = p ->next;
 183     }
 184     o = o->next;
 185   }
 186
 187   return true;
 188 }