gdb/dicos-tdep.c

   1 /* Target-dependent, architecture-independent code for DICOS, for GDB.
   2
   3    Copyright (C) 2009-2015 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 "solib.h"
  23 #include "solib-target.h"
  24 #include "inferior.h"
  25 #include "dicos-tdep.h"
  26
  27 void
  28 dicos_init_abi (struct gdbarch *gdbarch)
  29 {
  30   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  31
  32   set_solib_ops (gdbarch, &solib_target_so_ops);
  33
  34   /* Every process, although has its own address space, sees the same
  35      list of shared libraries.  There's no "main executable" in DICOS,
  36      so this accounts for all code.  */
  37   set_gdbarch_has_global_solist (gdbarch, 1);
  38
  39   /* The DICOS breakpoint API takes care of magically making
  40      breakpoints visible to all inferiors.  */
  41   set_gdbarch_has_global_breakpoints (gdbarch, 1);
  42
  43   /* There's no (standard definition of) entry point or a guaranteed
  44      text location with a symbol where to place the call dummy, so we
  45      need it on the stack.  Rely on i386_gdbarch_init used also for
  46      amd64 to set up ON_STACK inferior calls.  */
  47
  48   /* DICOS rewinds the PC itself.  */
  49   set_gdbarch_decr_pc_after_break (gdbarch, 0);
  50 }
  51
  52 /* Return true if ABFD is a dicos load module.  HEADER_SIZE is the
  53    expected size of the "header" section in bytes.  */
  54
  55 int
  56 dicos_load_module_p (bfd *abfd, int header_size)
  57 {
  58   long storage_needed;
  59   int ret = 0;
  60   asymbol **symbol_table = NULL;
  61   const char *symname = "Dicos_loadModuleInfo";
  62   asection *section;
  63
  64   /* DICOS files don't have a .note.ABI-tag marker or something
  65      similar.  We do know there's always a "header" section of
  66      HEADER_SIZE bytes (size depends on architecture), and there's
  67      always a "Dicos_loadModuleInfo" symbol defined.  Look for the
  68      section first, as that should be cheaper.  */
  69
  70   section = bfd_get_section_by_name (abfd, "header");
  71   if (!section)
  72     return 0;
  73
  74   if (bfd_section_size (abfd, section) != header_size)
  75     return 0;
  76
  77   /* Dicos LMs always have a "Dicos_loadModuleInfo" symbol
  78      defined.  Look for it.  */
  79
  80   storage_needed = bfd_get_symtab_upper_bound (abfd);
  81   if (storage_needed < 0)
  82     {
  83       warning (_("Can't read elf symbols from %s: %s"),
  84                bfd_get_filename (abfd),
  85                bfd_errmsg (bfd_get_error ()));
  86       return 0;
  87     }
  88
  89   if (storage_needed > 0)
  90     {
  91       long i, symcount;
  92
  93       symbol_table = (asymbol **) xmalloc (storage_needed);
  94       symcount = bfd_canonicalize_symtab (abfd, symbol_table);
  95
  96       if (symcount < 0)
  97         warning (_("Can't read elf symbols from %s: %s"),
  98                  bfd_get_filename (abfd),
  99                  bfd_errmsg (bfd_get_error ()));
 100       else
 101         {
 102           for (i = 0; i < symcount; i++)
 103             {
 104               asymbol *sym = symbol_table[i];
 105               if (sym->name != NULL
 106                   && symname[0] == sym->name[0]
 107                   && strcmp (symname + 1, sym->name + 1) == 0)
 108                 {
 109                   ret = 1;
 110                   break;
 111                 }
 112             }
 113         }
 114     }
 115
 116   xfree (symbol_table);
 117   return ret;
 118 }