gdb/cp-abi.c

   1 /* Generic code for supporting multiple C++ ABI's
   2
   3    Copyright (C) 2001-2013 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 "value.h"
  22 #include "cp-abi.h"
  23 #include "command.h"
  24 #include "exceptions.h"
  25 #include "gdbcmd.h"
  26 #include "ui-out.h"
  27 #include "gdb_assert.h"
  28 #include "gdb_string.h"
  29
  30 static struct cp_abi_ops *find_cp_abi (const char *short_name);
  31
  32 static struct cp_abi_ops current_cp_abi = { "", NULL };
  33 static struct cp_abi_ops auto_cp_abi = { "auto", NULL };
  34
  35 #define CP_ABI_MAX 8
  36 static struct cp_abi_ops *cp_abis[CP_ABI_MAX];
  37 static int num_cp_abis = 0;
  38
  39 enum ctor_kinds
  40 is_constructor_name (const char *name)
  41 {
  42   if ((current_cp_abi.is_constructor_name) == NULL)
  43     error (_("ABI doesn't define required function is_constructor_name"));
  44   return (*current_cp_abi.is_constructor_name) (name);
  45 }
  46
  47 enum dtor_kinds
  48 is_destructor_name (const char *name)
  49 {
  50   if ((current_cp_abi.is_destructor_name) == NULL)
  51     error (_("ABI doesn't define required function is_destructor_name"));
  52   return (*current_cp_abi.is_destructor_name) (name);
  53 }
  54
  55 int
  56 is_vtable_name (const char *name)
  57 {
  58   if ((current_cp_abi.is_vtable_name) == NULL)
  59     error (_("ABI doesn't define required function is_vtable_name"));
  60   return (*current_cp_abi.is_vtable_name) (name);
  61 }
  62
  63 int
  64 is_operator_name (const char *name)
  65 {
  66   if ((current_cp_abi.is_operator_name) == NULL)
  67     error (_("ABI doesn't define required function is_operator_name"));
  68   return (*current_cp_abi.is_operator_name) (name);
  69 }
  70
  71 int
  72 baseclass_offset (struct type *type, int index, const gdb_byte *valaddr,
  73                   int embedded_offset, CORE_ADDR address,
  74                   const struct value *val)
  75 {
  76   volatile struct gdb_exception ex;
  77   int res = 0;
  78
  79   gdb_assert (current_cp_abi.baseclass_offset != NULL);
  80
  81   TRY_CATCH (ex, RETURN_MASK_ERROR)
  82     {
  83       res = (*current_cp_abi.baseclass_offset) (type, index, valaddr,
  84                                                 embedded_offset,
  85                                                 address, val);
  86     }
  87
  88   if (ex.reason < 0 && ex.error == NOT_AVAILABLE_ERROR)
  89     throw_error (NOT_AVAILABLE_ERROR,
  90                  _("Cannot determine virtual baseclass offset "
  91                    "of incomplete object"));
  92   else if (ex.reason < 0)
  93     throw_exception (ex);
  94   else
  95     return res;
  96 }
  97
  98 struct value *
  99 value_virtual_fn_field (struct value **arg1p,
 100                         struct fn_field *f, int j,
 101                         struct type *type, int offset)
 102 {
 103   if ((current_cp_abi.virtual_fn_field) == NULL)
 104     return NULL;
 105   return (*current_cp_abi.virtual_fn_field) (arg1p, f, j,
 106                                              type, offset);
 107 }
 108
 109 struct type *
 110 value_rtti_type (struct value *v, int *full,
 111                  int *top, int *using_enc)
 112 {
 113   struct type *ret = NULL;
 114   volatile struct gdb_exception e;
 115
 116   if ((current_cp_abi.rtti_type) == NULL)
 117     return NULL;
 118   TRY_CATCH (e, RETURN_MASK_ERROR)
 119     {
 120       ret = (*current_cp_abi.rtti_type) (v, full, top, using_enc);
 121     }
 122   if (e.reason < 0)
 123     return NULL;
 124   return ret;
 125 }
 126
 127 void
 128 cplus_print_method_ptr (const gdb_byte *contents,
 129                         struct type *type,
 130                         struct ui_file *stream)
 131 {
 132   if (current_cp_abi.print_method_ptr == NULL)
 133     error (_("GDB does not support pointers to methods on this target"));
 134   (*current_cp_abi.print_method_ptr) (contents, type, stream);
 135 }
 136
 137 int
 138 cplus_method_ptr_size (struct type *to_type)
 139 {
 140   if (current_cp_abi.method_ptr_size == NULL)
 141     error (_("GDB does not support pointers to methods on this target"));
 142   return (*current_cp_abi.method_ptr_size) (to_type);
 143 }
 144
 145 void
 146 cplus_make_method_ptr (struct type *type, gdb_byte *contents,
 147                        CORE_ADDR value, int is_virtual)
 148 {
 149   if (current_cp_abi.make_method_ptr == NULL)
 150     error (_("GDB does not support pointers to methods on this target"));
 151   (*current_cp_abi.make_method_ptr) (type, contents, value, is_virtual);
 152 }
 153
 154 CORE_ADDR
 155 cplus_skip_trampoline (struct frame_info *frame,
 156                        CORE_ADDR stop_pc)
 157 {
 158   if (current_cp_abi.skip_trampoline == NULL)
 159     return 0;
 160   return (*current_cp_abi.skip_trampoline) (frame, stop_pc);
 161 }
 162
 163 struct value *
 164 cplus_method_ptr_to_value (struct value **this_p,
 165                            struct value *method_ptr)
 166 {
 167   if (current_cp_abi.method_ptr_to_value == NULL)
 168     error (_("GDB does not support pointers to methods on this target"));
 169   return (*current_cp_abi.method_ptr_to_value) (this_p, method_ptr);
 170 }
 171
 172 /* See cp-abi.h.  */
 173
 174 void
 175 cplus_print_vtable (struct value *value)
 176 {
 177   if (current_cp_abi.print_vtable == NULL)
 178     error (_("GDB cannot print the vtable on this target"));
 179   (*current_cp_abi.print_vtable) (value);
 180 }
 181
 182 int
 183 cp_pass_by_reference (struct type *type)
 184 {
 185   if ((current_cp_abi.pass_by_reference) == NULL)
 186     return 0;
 187   return (*current_cp_abi.pass_by_reference) (type);
 188 }
 189
 190 /* Set the current C++ ABI to SHORT_NAME.  */
 191
 192 static int
 193 switch_to_cp_abi (const char *short_name)
 194 {
 195   struct cp_abi_ops *abi;
 196
 197   abi = find_cp_abi (short_name);
 198   if (abi == NULL)
 199     return 0;
 200
 201   current_cp_abi = *abi;
 202   return 1;
 203 }
 204
 205 /* Add ABI to the list of supported C++ ABI's.  */
 206
 207 int
 208 register_cp_abi (struct cp_abi_ops *abi)
 209 {
 210   if (num_cp_abis == CP_ABI_MAX)
 211     internal_error (__FILE__, __LINE__,
 212                     _("Too many C++ ABIs, please increase "
 213                       "CP_ABI_MAX in cp-abi.c"));
 214
 215   cp_abis[num_cp_abis++] = abi;
 216
 217   return 1;
 218 }
 219
 220 /* Set the ABI to use in "auto" mode to SHORT_NAME.  */
 221
 222 void
 223 set_cp_abi_as_auto_default (const char *short_name)
 224 {
 225   char *new_longname, *new_doc;
 226   struct cp_abi_ops *abi = find_cp_abi (short_name);
 227
 228   if (abi == NULL)
 229     internal_error (__FILE__, __LINE__,
 230                     _("Cannot find C++ ABI \"%s\" to set it as auto default."),
 231                     short_name);
 232
 233   if (auto_cp_abi.longname != NULL)
 234     xfree ((char *) auto_cp_abi.longname);
 235   if (auto_cp_abi.doc != NULL)
 236     xfree ((char *) auto_cp_abi.doc);
 237
 238   auto_cp_abi = *abi;
 239
 240   auto_cp_abi.shortname = "auto";
 241   new_longname = xstrprintf ("currently \"%s\"", abi->shortname);
 242   auto_cp_abi.longname = new_longname;
 243
 244   new_doc = xstrprintf ("Automatically selected; currently \"%s\"",
 245              abi->shortname);
 246   auto_cp_abi.doc = new_doc;
 247
 248   /* Since we copy the current ABI into current_cp_abi instead of
 249      using a pointer, if auto is currently the default, we need to
 250      reset it.  */
 251   if (strcmp (current_cp_abi.shortname, "auto") == 0)
 252     switch_to_cp_abi ("auto");
 253 }
 254
 255 /* Return the ABI operations associated with SHORT_NAME.  */
 256
 257 static struct cp_abi_ops *
 258 find_cp_abi (const char *short_name)
 259 {
 260   int i;
 261
 262   for (i = 0; i < num_cp_abis; i++)
 263     if (strcmp (cp_abis[i]->shortname, short_name) == 0)
 264       return cp_abis[i];
 265
 266   return NULL;
 267 }
 268
 269 /* Display the list of registered C++ ABIs.  */
 270
 271 static void
 272 list_cp_abis (int from_tty)
 273 {
 274   struct ui_out *uiout = current_uiout;
 275   struct cleanup *cleanup_chain;
 276   int i;
 277
 278   ui_out_text (uiout, "The available C++ ABIs are:\n");
 279   cleanup_chain = make_cleanup_ui_out_tuple_begin_end (uiout,
 280                                                        "cp-abi-list");
 281   for (i = 0; i < num_cp_abis; i++)
 282     {
 283       char pad[14];
 284       int padcount;
 285
 286       ui_out_text (uiout, "  ");
 287       ui_out_field_string (uiout, "cp-abi", cp_abis[i]->shortname);
 288
 289       padcount = 16 - 2 - strlen (cp_abis[i]->shortname);
 290       pad[padcount] = 0;
 291       while (padcount > 0)
 292         pad[--padcount] = ' ';
 293       ui_out_text (uiout, pad);
 294
 295       ui_out_field_string (uiout, "doc", cp_abis[i]->doc);
 296       ui_out_text (uiout, "\n");
 297     }
 298   do_cleanups (cleanup_chain);
 299 }
 300
 301 /* Set the current C++ ABI, or display the list of options if no
 302    argument is given.  */
 303
 304 static void
 305 set_cp_abi_cmd (char *args, int from_tty)
 306 {
 307   if (args == NULL)
 308     {
 309       list_cp_abis (from_tty);
 310       return;
 311     }
 312
 313   if (!switch_to_cp_abi (args))
 314     error (_("Could not find \"%s\" in ABI list"), args);
 315 }
 316
 317 /* A completion function for "set cp-abi".  */
 318
 319 static VEC (char_ptr) *
 320 cp_abi_completer (struct cmd_list_element *ignore,
 321                   char *text, char *word)
 322 {
 323   static const char **cp_abi_names;
 324
 325   if (cp_abi_names == NULL)
 326     {
 327       int i;
 328
 329       cp_abi_names = XNEWVEC (const char *, num_cp_abis + 1);
 330       for (i = 0; i < num_cp_abis; ++i)
 331         cp_abi_names[i] = cp_abis[i]->shortname;
 332       cp_abi_names[i] = NULL;
 333     }
 334
 335   return complete_on_enum (cp_abi_names, text, word);
 336 }
 337
 338 /* Show the currently selected C++ ABI.  */
 339
 340 static void
 341 show_cp_abi_cmd (char *args, int from_tty)
 342 {
 343   struct ui_out *uiout = current_uiout;
 344
 345   ui_out_text (uiout, "The currently selected C++ ABI is \"");
 346
 347   ui_out_field_string (uiout, "cp-abi", current_cp_abi.shortname);
 348   ui_out_text (uiout, "\" (");
 349   ui_out_field_string (uiout, "longname", current_cp_abi.longname);
 350   ui_out_text (uiout, ").\n");
 351 }
 352
 353 extern initialize_file_ftype _initialize_cp_abi; /* -Wmissing-prototypes */
 354
 355 void
 356 _initialize_cp_abi (void)
 357 {
 358   struct cmd_list_element *c;
 359
 360   register_cp_abi (&auto_cp_abi);
 361   switch_to_cp_abi ("auto");
 362
 363   c = add_cmd ("cp-abi", class_obscure, set_cp_abi_cmd, _("\
 364 Set the ABI used for inspecting C++ objects.\n\
 365 \"set cp-abi\" with no arguments will list the available ABIs."),
 366                &setlist);
 367   set_cmd_completer (c, cp_abi_completer);
 368
 369   add_cmd ("cp-abi", class_obscure, show_cp_abi_cmd,
 370            _("Show the ABI used for inspecting C++ objects."),
 371            &showlist);
 372 }