contrib/gdb-6.2.1/gdb/demangle.c

   1 /* Basic C++ demangling support for GDB.
   2
   3    Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000,
   4    2001, 2003 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 2 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, write to the Free Software
  22    Foundation, Inc., 59 Temple Place - Suite 330,
  23    Boston, MA 02111-1307, USA.  */
  24
  25
  26 /*  This file contains support code for C++ demangling that is common
  27    to a styles of demangling, and GDB specific. */
  28
  29 #include "defs.h"
  30 #include "command.h"
  31 #include "gdbcmd.h"
  32 #include "demangle.h"
  33 #include "gdb_string.h"
  34
  35 /* Select the default C++ demangling style to use.  The default is "auto",
  36    which allows gdb to attempt to pick an appropriate demangling style for
  37    the executable it has loaded.  It can be set to a specific style ("gnu",
  38    "lucid", "arm", "hp", etc.) in which case gdb will never attempt to do auto
  39    selection of the style unless you do an explicit "set demangle auto".
  40    To select one of these as the default, set DEFAULT_DEMANGLING_STYLE in
  41    the appropriate target configuration file. */
  42
  43 #ifndef DEFAULT_DEMANGLING_STYLE
  44 #define DEFAULT_DEMANGLING_STYLE AUTO_DEMANGLING_STYLE_STRING
  45 #endif
  46
  47 extern void _initialize_demangler (void);
  48
  49 /* String name for the current demangling style.  Set by the
  50    "set demangle-style" command, printed as part of the output by the
  51    "show demangle-style" command. */
  52
  53 static char *current_demangling_style_string;
  54
  55 /* The array of names of the known demanglyng styles.  Generated by
  56    _initialize_demangler from libiberty_demanglers[] array.  */
  57
  58 static const char **demangling_style_names;
  59
  60 static void set_demangling_command (char *, int, struct cmd_list_element *);
  61
  62 /* Set current demangling style.  Called by the "set demangle-style"
  63    command after it has updated the current_demangling_style_string to
  64    match what the user has entered.
  65
  66    If the user has entered a string that matches a known demangling style
  67    name in the demanglers[] array then just leave the string alone and update
  68    the current_demangling_style enum value to match.
  69
  70    If the user has entered a string that doesn't match, including an empty
  71    string, then print a list of the currently known styles and restore
  72    the current_demangling_style_string to match the current_demangling_style
  73    enum value.
  74
  75    Note:  Assumes that current_demangling_style_string always points to
  76    a malloc'd string, even if it is a null-string. */
  77
  78 static void
  79 set_demangling_command (char *ignore, int from_tty, struct cmd_list_element *c)
  80 {
  81   const struct demangler_engine *dem;
  82
  83   /*  First just try to match whatever style name the user supplied with
  84      one of the known ones.  Don't bother special casing for an empty
  85      name, we just treat it as any other style name that doesn't match.
  86      If we match, update the current demangling style enum. */
  87
  88   for (dem = libiberty_demanglers;
  89        dem->demangling_style != unknown_demangling;
  90        dem++)
  91     {
  92       if (strcmp (current_demangling_style_string,
  93                   dem->demangling_style_name) == 0)
  94         {
  95           current_demangling_style = dem->demangling_style;
  96           break;
  97         }
  98     }
  99
 100   /* Check to see if we found a match.  If not, gripe about any non-empty
 101      style name and supply a list of valid ones.  FIXME:  This should
 102      probably be done with some sort of completion and with help. */
 103
 104   if (dem->demangling_style == unknown_demangling)
 105     {
 106       if (*current_demangling_style_string != '\0')
 107         {
 108           printf_unfiltered ("Unknown demangling style `%s'.\n",
 109                              current_demangling_style_string);
 110         }
 111       printf_unfiltered ("The currently understood settings are:\n\n");
 112       for (dem = libiberty_demanglers;
 113            dem->demangling_style != unknown_demangling;
 114            dem++)
 115         {
 116           printf_unfiltered ("%-10s %s\n", dem->demangling_style_name,
 117                              dem->demangling_style_doc);
 118           if (dem->demangling_style == current_demangling_style)
 119             {
 120               xfree (current_demangling_style_string);
 121               current_demangling_style_string =
 122                 savestring (dem->demangling_style_name,
 123                             strlen (dem->demangling_style_name));
 124             }
 125         }
 126       if (current_demangling_style == unknown_demangling)
 127         {
 128           /* This can happen during initialization if gdb is compiled with
 129              a DEMANGLING_STYLE value that is unknown, so pick the first
 130              one as the default. */
 131           current_demangling_style = libiberty_demanglers[0].demangling_style;
 132           current_demangling_style_string =
 133             savestring (
 134               libiberty_demanglers[0].demangling_style_name,
 135               strlen (libiberty_demanglers[0].demangling_style_name));
 136           warning ("`%s' style demangling chosen as the default.\n",
 137                    current_demangling_style_string);
 138         }
 139     }
 140 }
 141
 142 /* Fake a "set demangle-style" command. */
 143
 144 void
 145 set_demangling_style (char *style)
 146 {
 147   if (current_demangling_style_string != NULL)
 148     {
 149       xfree (current_demangling_style_string);
 150     }
 151   current_demangling_style_string = savestring (style, strlen (style));
 152   set_demangling_command ((char *) NULL, 0, (struct cmd_list_element *) NULL);
 153 }
 154
 155 /* G++ uses a special character to indicate certain internal names.  Which
 156    character it is depends on the platform:
 157    - Usually '$' on systems where the assembler will accept that
 158    - Usually '.' otherwise (this includes most sysv4-like systems and most
 159      ELF targets)
 160    - Occasionally '_' if neither of the above is usable
 161
 162    We check '$' first because it is the safest, and '.' often has another
 163    meaning.  We don't currently try to handle '_' because the precise forms
 164    of the names are different on those targets.  */
 165
 166 static char cplus_markers[] = {'$', '.', '\0'};
 167
 168 int
 169 is_cplus_marker (int c)
 170 {
 171   return c && strchr (cplus_markers, c) != NULL;
 172 }
 173
 174 void
 175 _initialize_demangler (void)
 176 {
 177   struct cmd_list_element *set, *show;
 178   int i, ndems;
 179
 180   /* Fill the demangling_style_names[] array.  */
 181   for (ndems = 0;
 182        libiberty_demanglers[ndems].demangling_style != unknown_demangling;
 183        ndems++)
 184     ;
 185   demangling_style_names = xcalloc (ndems + 1, sizeof (char *));
 186   for (i = 0;
 187        libiberty_demanglers[i].demangling_style != unknown_demangling;
 188        i++)
 189     demangling_style_names[i] =
 190       xstrdup (libiberty_demanglers[i].demangling_style_name);
 191
 192   set = add_set_enum_cmd ("demangle-style", class_support,
 193                           demangling_style_names,
 194                           (const char **) &current_demangling_style_string,
 195                           "Set the current C++ demangling style.\n\
 196 Use `set demangle-style' without arguments for a list of demangling styles.",
 197                           &setlist);
 198   show = add_show_from_set (set, &showlist);
 199   set_cmd_sfunc (set, set_demangling_command);
 200
 201   /* Set the default demangling style chosen at compilation time. */
 202   set_demangling_style (DEFAULT_DEMANGLING_STYLE);
 203 }