1/* Target-dependent, architecture-independent code for DICOS, for GDB.
2
3   Copyright (C) 2009-2020 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#include "gdbarch.h"
27
28void
29dicos_init_abi (struct gdbarch *gdbarch)
30{
31  set_solib_ops (gdbarch, &solib_target_so_ops);
32
33  /* Every process, although has its own address space, sees the same
34     list of shared libraries.  There's no "main executable" in DICOS,
35     so this accounts for all code.  */
36  set_gdbarch_has_global_solist (gdbarch, 1);
37
38  /* The DICOS breakpoint API takes care of magically making
39     breakpoints visible to all inferiors.  */
40  set_gdbarch_has_global_breakpoints (gdbarch, 1);
41
42  /* There's no (standard definition of) entry point or a guaranteed
43     text location with a symbol where to place the call dummy, so we
44     need it on the stack.  Rely on i386_gdbarch_init used also for
45     amd64 to set up ON_STACK inferior calls.  */
46
47  /* DICOS rewinds the PC itself.  */
48  set_gdbarch_decr_pc_after_break (gdbarch, 0);
49}
50
51/* Return true if ABFD is a dicos load module.  HEADER_SIZE is the
52   expected size of the "header" section in bytes.  */
53
54int
55dicos_load_module_p (bfd *abfd, int header_size)
56{
57  long storage_needed;
58  int ret = 0;
59  asymbol **symbol_table = NULL;
60  const char *symname = "Dicos_loadModuleInfo";
61  asection *section;
62
63  /* DICOS files don't have a .note.ABI-tag marker or something
64     similar.  We do know there's always a "header" section of
65     HEADER_SIZE bytes (size depends on architecture), and there's
66     always a "Dicos_loadModuleInfo" symbol defined.  Look for the
67     section first, as that should be cheaper.  */
68
69  section = bfd_get_section_by_name (abfd, "header");
70  if (!section)
71    return 0;
72
73  if (bfd_section_size (section) != header_size)
74    return 0;
75
76  /* Dicos LMs always have a "Dicos_loadModuleInfo" symbol
77     defined.  Look for it.  */
78
79  storage_needed = bfd_get_symtab_upper_bound (abfd);
80  if (storage_needed < 0)
81    {
82      warning (_("Can't read elf symbols from %s: %s"),
83	       bfd_get_filename (abfd),
84	       bfd_errmsg (bfd_get_error ()));
85      return 0;
86    }
87
88  if (storage_needed > 0)
89    {
90      long i, symcount;
91
92      symbol_table = (asymbol **) xmalloc (storage_needed);
93      symcount = bfd_canonicalize_symtab (abfd, symbol_table);
94
95      if (symcount < 0)
96	warning (_("Can't read elf symbols from %s: %s"),
97		 bfd_get_filename (abfd),
98		 bfd_errmsg (bfd_get_error ()));
99      else
100	{
101	  for (i = 0; i < symcount; i++)
102	    {
103	      asymbol *sym = symbol_table[i];
104	      if (sym->name != NULL
105		  && symname[0] == sym->name[0]
106		  && strcmp (symname + 1, sym->name + 1) == 0)
107		{
108		  ret = 1;
109		  break;
110		}
111	    }
112	}
113    }
114
115  xfree (symbol_table);
116  return ret;
117}
118