gdb/bfd-target.c

   1 /* Very simple "bfd" target, for GDB, the GNU debugger.
   2
   3    Copyright 2003 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   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,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "target.h"
  24 #include "bfd-target.h"
  25 #include "gdb_assert.h"
  26 #include "gdb_string.h"
  27
  28 /* Locate all mappable sections of a BFD file, filling in a target
  29    section for each.  */
  30
  31 struct section_closure
  32 {
  33   struct section_table *end;
  34 };
  35
  36 static void
  37 add_to_section_table (struct bfd *abfd, struct bfd_section *asect,
  38                       void *closure)
  39 {
  40   struct section_closure *pp = closure;
  41   flagword aflag;
  42
  43   /* NOTE: cagney/2003-10-22: Is this pruning useful?  */
  44   aflag = bfd_get_section_flags (abfd, asect);
  45   if (!(aflag & SEC_ALLOC))
  46     return;
  47   if (bfd_section_size (abfd, asect) == 0)
  48     return;
  49   pp->end->bfd = abfd;
  50   pp->end->the_bfd_section = asect;
  51   pp->end->addr = bfd_section_vma (abfd, asect);
  52   pp->end->endaddr = pp->end->addr + bfd_section_size (abfd, asect);
  53   pp->end++;
  54 }
  55
  56 void
  57 build_target_sections_from_bfd (struct target_ops *targ, struct bfd *abfd)
  58 {
  59   unsigned count;
  60   struct section_table *start;
  61   struct section_closure cl;
  62
  63   count = bfd_count_sections (abfd);
  64   target_resize_to_sections (targ, count);
  65   start = targ->to_sections;
  66   cl.end = targ->to_sections;
  67   bfd_map_over_sections (abfd, add_to_section_table, &cl);
  68   gdb_assert (cl.end - start <= count);
  69 }
  70
  71 LONGEST
  72 target_bfd_xfer_partial (struct target_ops *ops,
  73                          enum target_object object,
  74                          const char *annex, const void *writebuf,
  75                          void *readbuf, ULONGEST offset, LONGEST len)
  76 {
  77   switch (object)
  78     {
  79     case TARGET_OBJECT_MEMORY:
  80       {
  81         struct section_table *s = target_section_by_addr (ops, offset);
  82         if (s == NULL)
  83           return -1;
  84         /* If the length extends beyond the section, truncate it.  Be
  85            careful to not suffer from overflow (wish S contained a
  86            length).  */
  87         if ((offset - s->addr + len) > (s->endaddr - s->addr))
  88           len = (s->endaddr - s->addr) - (offset - s->addr);
  89         if (readbuf != NULL
  90             && !bfd_get_section_contents (s->bfd, s->the_bfd_section,
  91                                           readbuf, offset - s->addr, len))
  92           return -1;
  93 #if 1
  94         if (writebuf != NULL)
  95           return -1;
  96 #else
  97         /* FIXME: cagney/2003-10-31: The BFD interface doesn't yet
  98            take a const buffer.  */
  99         if (writebuf != NULL
 100             && !bfd_set_section_contents (s->bfd, s->the_bfd_section,
 101                                           writebuf, offset - s->addr, len))
 102           return -1;
 103 #endif
 104         return len;
 105       }
 106     default:
 107       return -1;
 108     }
 109 }
 110
 111 void
 112 target_bfd_xclose (struct target_ops *t, int quitting)
 113 {
 114   bfd_close (t->to_data);
 115   xfree (t->to_sections);
 116   xfree (t);
 117 }
 118
 119 struct target_ops *
 120 target_bfd_reopen (struct bfd *bfd)
 121 {
 122   struct target_ops *t = XZALLOC (struct target_ops);
 123   t->to_shortname = "bfd";
 124   t->to_longname = "BFD backed target";
 125   t->to_doc = "You should never see this";
 126   t->to_xfer_partial = target_bfd_xfer_partial;
 127   t->to_xclose = target_bfd_xclose;
 128   t->to_data = bfd;
 129   build_target_sections_from_bfd (t, bfd);
 130   return t;
 131 }