gdb/dicos-tdep.c

   1 /* Target-dependent, architecture-independent code for DICOS, for GDB.
   2
   3    Copyright (C) 2009-2014 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 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, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "osabi.h"
  22 #include <string.h>
  23 #include "solib.h"
  24 #include "solib-target.h"
  25 #include "inferior.h"
  26 #include "dicos-tdep.h"
  27
  28 void
  29 dicos_init_abi (struct gdbarch *gdbarch)
  30 {
  31   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  32
  33   set_solib_ops (gdbarch, &solib_target_so_ops);
  34
  35   /* Every process, although has its own address space, sees the same
  36      list of shared libraries.  There's no "main executable" in DICOS,
  37      so this accounts for all code.  */
  38   set_gdbarch_has_global_solist (gdbarch, 1);
  39
  40   /* The DICOS breakpoint API takes care of magically making
  41      breakpoints visible to all inferiors.  */
  42   set_gdbarch_has_global_breakpoints (gdbarch, 1);
  43
  44   /* There's no (standard definition of) entry point or a guaranteed
  45      text location with a symbol where to place the call dummy, so we
  46      need it on the stack.  Rely on i386_gdbarch_init used also for
  47      amd64 to set up ON_STACK inferior calls.  */
  48
  49   /* DICOS rewinds the PC itself.  */
  50   set_gdbarch_decr_pc_after_break (gdbarch, 0);
  51 }
  52
  53 /* Return true if ABFD is a dicos load module.  HEADER_SIZE is the
  54    expected size of the "header" section in bytes.  */
  55
  56 int
  57 dicos_load_module_p (bfd *abfd, int header_size)
  58 {
  59   long storage_needed;
  60   int ret = 0;
  61   asymbol **symbol_table = NULL;
  62   const char *symname = "Dicos_loadModuleInfo";
  63   asection *section;
  64
  65   /* DICOS files don't have a .note.ABI-tag marker or something
  66      similar.  We do know there's always a "header" section of
  67      HEADER_SIZE bytes (size depends on architecture), and there's
  68      always a "Dicos_loadModuleInfo" symbol defined.  Look for the
  69      section first, as that should be cheaper.  */
  70
  71   section = bfd_get_section_by_name (abfd, "header");
  72   if (!section)
  73     return 0;
  74
  75   if (bfd_section_size (abfd, section) != header_size)
  76     return 0;
  77
  78   /* Dicos LMs always have a "Dicos_loadModuleInfo" symbol
  79      defined.  Look for it.  */
  80
  81   storage_needed = bfd_get_symtab_upper_bound (abfd);
  82   if (storage_needed < 0)
  83     {
  84       warning (_("Can't read elf symbols from %s: %s"),
  85                bfd_get_filename (abfd),
  86                bfd_errmsg (bfd_get_error ()));
  87       return 0;
  88     }
  89
  90   if (storage_needed > 0)
  91     {
  92       long i, symcount;
  93
  94       symbol_table = xmalloc (storage_needed);
  95       symcount = bfd_canonicalize_symtab (abfd, symbol_table);
  96
  97       if (symcount < 0)
  98         warning (_("Can't read elf symbols from %s: %s"),
  99                  bfd_get_filename (abfd),
 100                  bfd_errmsg (bfd_get_error ()));
 101       else
 102         {
 103           for (i = 0; i < symcount; i++)
 104             {
 105               asymbol *sym = symbol_table[i];
 106               if (sym->name != NULL
 107                   && symname[0] == sym->name[0]
 108                   && strcmp (symname + 1, sym->name + 1) == 0)
 109                 {
 110                   ret = 1;
 111                   break;
 112                 }
 113             }
 114         }
 115     }
 116
 117   xfree (symbol_table);
 118   return ret;
 119 }