1/* Basic C++ demangling support for GDB.
2
3   Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
4   2003, 2007 Free Software Foundation, Inc.
5
6   Written by Fred Fish at Cygnus Support.
7
8   This file is part of GDB.
9
10   This program is free software; you can redistribute it and/or modify
11   it under the terms of the GNU General Public License as published by
12   the Free Software Foundation; either version 3 of the License, or
13   (at your option) any later version.
14
15   This program is distributed in the hope that it will be useful,
16   but WITHOUT ANY WARRANTY; without even the implied warranty of
17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18   GNU General Public License for more details.
19
20   You should have received a copy of the GNU General Public License
21   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
22
23
24/*  This file contains support code for C++ demangling that is common
25   to a styles of demangling, and GDB specific. */
26
27#include "defs.h"
28#include "command.h"
29#include "gdbcmd.h"
30#include "demangle.h"
31#include "gdb_string.h"
32
33/* Select the default C++ demangling style to use.  The default is "auto",
34   which allows gdb to attempt to pick an appropriate demangling style for
35   the executable it has loaded.  It can be set to a specific style ("gnu",
36   "lucid", "arm", "hp", etc.) in which case gdb will never attempt to do auto
37   selection of the style unless you do an explicit "set demangle auto".
38   To select one of these as the default, set DEFAULT_DEMANGLING_STYLE in
39   the appropriate target configuration file. */
40
41#ifndef DEFAULT_DEMANGLING_STYLE
42#define DEFAULT_DEMANGLING_STYLE AUTO_DEMANGLING_STYLE_STRING
43#endif
44
45extern void _initialize_demangler (void);
46
47/* String name for the current demangling style.  Set by the
48   "set demangle-style" command, printed as part of the output by the
49   "show demangle-style" command. */
50
51static char *current_demangling_style_string;
52
53/* The array of names of the known demanglyng styles.  Generated by
54   _initialize_demangler from libiberty_demanglers[] array.  */
55
56static const char **demangling_style_names;
57static void
58show_demangling_style_names(struct ui_file *file, int from_tty,
59			    struct cmd_list_element *c, const char *value)
60{
61  fprintf_filtered (file, _("The current C++ demangling style is \"%s\".\n"),
62		    value);
63}
64
65
66static void set_demangling_command (char *, int, struct cmd_list_element *);
67
68/* Set current demangling style.  Called by the "set demangle-style"
69   command after it has updated the current_demangling_style_string to
70   match what the user has entered.
71
72   If the user has entered a string that matches a known demangling style
73   name in the demanglers[] array then just leave the string alone and update
74   the current_demangling_style enum value to match.
75
76   If the user has entered a string that doesn't match, including an empty
77   string, then print a list of the currently known styles and restore
78   the current_demangling_style_string to match the current_demangling_style
79   enum value.
80
81   Note:  Assumes that current_demangling_style_string always points to
82   a malloc'd string, even if it is a null-string. */
83
84static void
85set_demangling_command (char *ignore, int from_tty, struct cmd_list_element *c)
86{
87  const struct demangler_engine *dem;
88
89  /*  First just try to match whatever style name the user supplied with
90     one of the known ones.  Don't bother special casing for an empty
91     name, we just treat it as any other style name that doesn't match.
92     If we match, update the current demangling style enum. */
93
94  for (dem = libiberty_demanglers;
95       dem->demangling_style != unknown_demangling;
96       dem++)
97    {
98      if (strcmp (current_demangling_style_string,
99		  dem->demangling_style_name) == 0)
100	{
101	  current_demangling_style = dem->demangling_style;
102	  break;
103	}
104    }
105
106  /* Check to see if we found a match.  If not, gripe about any non-empty
107     style name and supply a list of valid ones.  FIXME:  This should
108     probably be done with some sort of completion and with help. */
109
110  if (dem->demangling_style == unknown_demangling)
111    {
112      if (*current_demangling_style_string != '\0')
113	{
114	  printf_unfiltered (_("Unknown demangling style `%s'.\n"),
115			     current_demangling_style_string);
116	}
117      printf_unfiltered (_("The currently understood settings are:\n\n"));
118      for (dem = libiberty_demanglers;
119	   dem->demangling_style != unknown_demangling;
120	   dem++)
121	{
122	  printf_unfiltered ("%-10s %s\n", dem->demangling_style_name,
123			     dem->demangling_style_doc);
124	  if (dem->demangling_style == current_demangling_style)
125	    {
126	      xfree (current_demangling_style_string);
127	      current_demangling_style_string =
128		savestring (dem->demangling_style_name,
129			    strlen (dem->demangling_style_name));
130	    }
131	}
132      if (current_demangling_style == unknown_demangling)
133	{
134	  /* This can happen during initialization if gdb is compiled with
135	     a DEMANGLING_STYLE value that is unknown, so pick the first
136	     one as the default. */
137	  current_demangling_style = libiberty_demanglers[0].demangling_style;
138	  current_demangling_style_string =
139	    savestring (
140              libiberty_demanglers[0].demangling_style_name,
141	      strlen (libiberty_demanglers[0].demangling_style_name));
142	  warning (_("`%s' style demangling chosen as the default."),
143		   current_demangling_style_string);
144	}
145    }
146}
147
148/* Fake a "set demangle-style" command. */
149
150void
151set_demangling_style (char *style)
152{
153  if (current_demangling_style_string != NULL)
154    {
155      xfree (current_demangling_style_string);
156    }
157  current_demangling_style_string = savestring (style, strlen (style));
158  set_demangling_command ((char *) NULL, 0, (struct cmd_list_element *) NULL);
159}
160
161/* G++ uses a special character to indicate certain internal names.  Which
162   character it is depends on the platform:
163   - Usually '$' on systems where the assembler will accept that
164   - Usually '.' otherwise (this includes most sysv4-like systems and most
165     ELF targets)
166   - Occasionally '_' if neither of the above is usable
167
168   We check '$' first because it is the safest, and '.' often has another
169   meaning.  We don't currently try to handle '_' because the precise forms
170   of the names are different on those targets.  */
171
172static char cplus_markers[] = {'$', '.', '\0'};
173
174int
175is_cplus_marker (int c)
176{
177  return c && strchr (cplus_markers, c) != NULL;
178}
179
180void
181_initialize_demangler (void)
182{
183  struct cmd_list_element *set, *show;
184  int i, ndems;
185
186  /* Fill the demangling_style_names[] array.  */
187  for (ndems = 0;
188       libiberty_demanglers[ndems].demangling_style != unknown_demangling;
189       ndems++)
190    ;
191  demangling_style_names = xcalloc (ndems + 1, sizeof (char *));
192  for (i = 0;
193       libiberty_demanglers[i].demangling_style != unknown_demangling;
194       i++)
195    demangling_style_names[i] =
196      xstrdup (libiberty_demanglers[i].demangling_style_name);
197
198  /* FIXME: cagney/2005-02-20: The code implementing this variable are
199     malloc-ing and free-ing current_demangling_style_string when it
200     should instead just point to an element of
201     demangling_style_names.  */
202  add_setshow_enum_cmd ("demangle-style", class_support,
203			demangling_style_names,
204			(const char **) &current_demangling_style_string, _("\
205Set the current C++ demangling style."), _("\
206Show the current C++ demangling style."), _("\
207Use `set demangle-style' without arguments for a list of demangling styles."),
208			set_demangling_command,
209			show_demangling_style_names,
210			&setlist, &showlist);
211
212  /* Set the default demangling style chosen at compilation time. */
213  set_demangling_style (DEFAULT_DEMANGLING_STYLE);
214}
215