aboutsummaryrefslogtreecommitdiff
path: root/gdb/demangle.c
blob: 2d79c1d8a43829843e110fd01023e1422f086389 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
/* Basic C++ demangling support for GDB.

   Copyright (C) 1991-2017 Free Software Foundation, Inc.

   Written by Fred Fish at Cygnus Support.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */


/*  This file contains support code for C++ demangling that is common
   to a styles of demangling, and GDB specific.  */

#include "defs.h"
#include "cli/cli-utils.h" /* for skip_to_space */
#include "command.h"
#include "gdbcmd.h"
#include "demangle.h"
#include "gdb-demangle.h"
#include "language.h"

/* Select the default C++ demangling style to use.  The default is "auto",
   which allows gdb to attempt to pick an appropriate demangling style for
   the executable it has loaded.  It can be set to a specific style ("gnu",
   "lucid", "arm", "hp", etc.) in which case gdb will never attempt to do auto
   selection of the style unless you do an explicit "set demangle auto".
   To select one of these as the default, set DEFAULT_DEMANGLING_STYLE in
   the appropriate target configuration file.  */

#ifndef DEFAULT_DEMANGLING_STYLE
#define DEFAULT_DEMANGLING_STYLE AUTO_DEMANGLING_STYLE_STRING
#endif

static void demangle_command (char *, int);

/* See documentation in gdb-demangle.h.  */
int demangle = 1;

static void
show_demangle (struct ui_file *file, int from_tty,
	       struct cmd_list_element *c, const char *value)
{
  fprintf_filtered (file,
		    _("Demangling of encoded C++/ObjC names "
		      "when displaying symbols is %s.\n"),
		    value);
}

/* See documentation in gdb-demangle.h.  */
int asm_demangle = 0;

static void
show_asm_demangle (struct ui_file *file, int from_tty,
		   struct cmd_list_element *c, const char *value)
{
  fprintf_filtered (file,
		    _("Demangling of C++/ObjC names in "
		      "disassembly listings is %s.\n"),
		    value);
}

/* String name for the current demangling style.  Set by the
   "set demangle-style" command, printed as part of the output by the
   "show demangle-style" command.  */

static const char *current_demangling_style_string;

/* The array of names of the known demanglyng styles.  Generated by
   _initialize_demangler from libiberty_demanglers[] array.  */

static const char **demangling_style_names;
static void
show_demangling_style_names(struct ui_file *file, int from_tty,
			    struct cmd_list_element *c, const char *value)
{
  fprintf_filtered (file, _("The current C++ demangling style is \"%s\".\n"),
		    value);
}

/* Set current demangling style.  Called by the "set demangle-style"
   command after it has updated the current_demangling_style_string to
   match what the user has entered.

   If the user has entered a string that matches a known demangling style
   name in the demanglers[] array then just leave the string alone and update
   the current_demangling_style enum value to match.

   If the user has entered a string that doesn't match, including an empty
   string, then print a list of the currently known styles and restore
   the current_demangling_style_string to match the current_demangling_style
   enum value.

   Note:  Assumes that current_demangling_style_string always points to
   a malloc'd string, even if it is a null-string.  */

static void
set_demangling_command (char *ignore, int from_tty, struct cmd_list_element *c)
{
  const struct demangler_engine *dem;
  int i;

  /*  First just try to match whatever style name the user supplied with
     one of the known ones.  Don't bother special casing for an empty
     name, we just treat it as any other style name that doesn't match.
     If we match, update the current demangling style enum.  */

  for (dem = libiberty_demanglers, i = 0;
       dem->demangling_style != unknown_demangling; 
       dem++)
    {
      if (strcmp (current_demangling_style_string,
		  dem->demangling_style_name) == 0)
	{
	  current_demangling_style = dem->demangling_style;
	  current_demangling_style_string = demangling_style_names[i];
	  break;
	}
      i++;
    }

  /* We should have found a match, given we only add known styles to
     the enumeration list.  */
  gdb_assert (dem->demangling_style != unknown_demangling);
}

/* G++ uses a special character to indicate certain internal names.  Which
   character it is depends on the platform:
   - Usually '$' on systems where the assembler will accept that
   - Usually '.' otherwise (this includes most sysv4-like systems and most
     ELF targets)
   - Occasionally '_' if neither of the above is usable

   We check '$' first because it is the safest, and '.' often has another
   meaning.  We don't currently try to handle '_' because the precise forms
   of the names are different on those targets.  */

static char cplus_markers[] = {'$', '.', '\0'};

/* See documentation in gdb-demangle.h.  */

int
is_cplus_marker (int c)
{
  return c && strchr (cplus_markers, c) != NULL;
}

/* Demangle the given string in the current language.  */

static void
demangle_command (char *args, int from_tty)
{
  char *demangled, *name, *lang_name = NULL;
  char *arg_buf, *arg_start;
  int processing_args = 1;
  const struct language_defn *lang;
  struct cleanup *cleanups;

  arg_buf = xstrdup (args != NULL ? args : "");
  cleanups = make_cleanup (xfree, arg_buf);
  arg_start = arg_buf;

  while (processing_args
	 && *arg_start == '-')
    {
      char *p = skip_to_space (arg_start);

      if (strncmp (arg_start, "-l", p - arg_start) == 0)
	{
	  char *lang_name_end;

	  lang_name = skip_spaces (p);
	  lang_name_end = skip_to_space (lang_name);
	  lang_name = savestring (lang_name, lang_name_end - lang_name);
	  make_cleanup (xfree, lang_name);
	  p = lang_name_end;
	}
      else if (strncmp (arg_start, "--", p - arg_start) == 0)
	processing_args = 0;
      else
	{
	  *p = '\0';
	  error (_("Unrecognized option '%s' to demangle command.  "
		   "Try \"help demangle\"."), arg_start);
	}

      arg_start = skip_spaces (p);
    }

  name = arg_start;

  if (*name == '\0')
    error (_("Usage: demangle [-l language] [--] name"));

  if (lang_name != NULL)
    {
      enum language lang_enum;

      lang_enum = language_enum (lang_name);
      if (lang_enum == language_unknown)
	error (_("Unknown language \"%s\""), lang_name);
      lang = language_def (lang_enum);
    }
  else
    lang = current_language;

  demangled = language_demangle (lang, name, DMGL_ANSI | DMGL_PARAMS);
  if (demangled != NULL)
    {
      printf_filtered ("%s\n", demangled);
      xfree (demangled);
    }
  else
    error (_("Can't demangle \"%s\""), name);

  do_cleanups (cleanups);
}

extern initialize_file_ftype _initialize_demangler; /* -Wmissing-prototypes */

void
_initialize_demangler (void)
{
  int i, ndems;

  /* Fill the demangling_style_names[] array, and set the default
     demangling style chosen at compilation time.  */
  for (ndems = 0;
       libiberty_demanglers[ndems].demangling_style != unknown_demangling; 
       ndems++)
    ;
  demangling_style_names = XCNEWVEC (const char *, ndems + 1);
  for (i = 0;
       libiberty_demanglers[i].demangling_style != unknown_demangling; 
       i++)
    {
      demangling_style_names[i]
	= xstrdup (libiberty_demanglers[i].demangling_style_name);

      if (current_demangling_style_string == NULL
	  && strcmp (DEFAULT_DEMANGLING_STYLE, demangling_style_names[i]) == 0)
	current_demangling_style_string = demangling_style_names[i];
    }

  add_setshow_boolean_cmd ("demangle", class_support, &demangle, _("\
Set demangling of encoded C++/ObjC names when displaying symbols."), _("\
Show demangling of encoded C++/ObjC names when displaying symbols."), NULL,
			   NULL,
			   show_demangle,
			   &setprintlist, &showprintlist);

  add_setshow_boolean_cmd ("asm-demangle", class_support, &asm_demangle, _("\
Set demangling of C++/ObjC names in disassembly listings."), _("\
Show demangling of C++/ObjC names in disassembly listings."), NULL,
			   NULL,
			   show_asm_demangle,
			   &setprintlist, &showprintlist);

  add_setshow_enum_cmd ("demangle-style", class_support,
			demangling_style_names,
			&current_demangling_style_string, _("\
Set the current C++ demangling style."), _("\
Show the current C++ demangling style."), _("\
Use `set demangle-style' without arguments for a list of demangling styles."),
			set_demangling_command,
			show_demangling_style_names,
			&setlist, &showlist);

  add_cmd ("demangle", class_support, demangle_command, _("\
Demangle a mangled name.\n\
Usage: demangle [-l language] [--] name\n\
If LANGUAGE is not specified, NAME is demangled in the current language."),
	   &cmdlist);
}