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   if ((output_section->flags & SEC_HAS_CONTENTS) != 0
  83       && seclet->size)
  84   {
  85     data = (PTR) bfd_get_relocated_section_contents(abfd, seclet, data,
  86                                                     relocateable);
  87     if(bfd_set_section_contents(abfd,
  88                                 output_section,
  89                                 data,
  90                                 seclet->offset,
  91                                 seclet->size) == false)
  92     {
  93       abort();
  94     }
  95   }
  96   return true;
  97 }
  98
  99 /* Put the contents of a seclet in its final destination.  */
 100
 101 static boolean
 102 DEFUN(seclet_dump_seclet,(abfd, seclet, section, data, relocateable),
 103       bfd *abfd AND
 104       bfd_seclet_type *seclet AND
 105       asection *section AND
 106       PTR data AND
 107       boolean relocateable)
 108 {
 109   switch (seclet->type)
 110     {
 111     case bfd_indirect_seclet:
 112       /* The contents of this section come from another one somewhere
 113          else */
 114       return rel(abfd, seclet, section, data, relocateable);
 115
 116     case bfd_fill_seclet:
 117       /* Fill in the section with us */
 118       {
 119         char *d = bfd_xmalloc(seclet->size);
 120         unsigned int i;
 121         for (i =0;  i < seclet->size; i+=2) {
 122           d[i] = seclet->u.fill.value >> 8;
 123         }
 124         for (i = 1; i < seclet->size; i+=2) {
 125           d[i] = seclet->u.fill.value ;
 126         }
 127         /* Don't bother to fill in empty sections */
 128         if (!(bfd_get_section_flags(abfd, section) & SEC_HAS_CONTENTS))
 129           {
 130             return true;
 131           }
 132         return bfd_set_section_contents(abfd, section, d, seclet->offset,
 133                                         seclet->size);
 134       }
 135
 136     default:
 137       abort();
 138     }
 139
 140   return true;
 141 }
 142
 143 /*
 144 INTERNAL_FUNCTION
 145         bfd_generic_seclet_link
 146
 147 SYNOPSIS
 148         boolean bfd_generic_seclet_link
 149          (bfd *abfd,
 150           PTR data,
 151           boolean relocateable);
 152
 153 DESCRIPTION
 154
 155         The generic seclet linking routine.  The caller should have
 156         set up seclets for all the output sections.  The DATA argument
 157         should point to a memory area large enough to hold the largest
 158         section.  This function looks through the seclets and moves
 159         the contents into the output sections.  If RELOCATEABLE is
 160         true, the orelocation fields of the output sections must
 161         already be initialized.
 162
 163 */
 164
 165 boolean
 166 DEFUN(bfd_generic_seclet_link,(abfd, data, relocateable),
 167       bfd *abfd AND
 168       PTR data AND
 169       boolean relocateable)
 170 {
 171   asection *o = abfd->sections;
 172   while (o != (asection *)NULL)
 173   {
 174     bfd_seclet_type *p = o->seclets_head;
 175     while (p != (bfd_seclet_type *)NULL)
 176     {
 177       if (seclet_dump_seclet(abfd, p, o, data, relocateable) == false)
 178         return false;
 179       p = p ->next;
 180     }
 181     o = o->next;
 182   }
 183
 184   return true;
 185 }