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 /* See cp-abi.h.  */
 183
 184 struct value *
 185 cplus_typeid (struct value *value)
 186 {
 187   if (current_cp_abi.get_typeid == NULL)
 188     error (_("GDB cannot find the typeid on this target"));
 189   return (*current_cp_abi.get_typeid) (value);
 190 }
 191
 192 /* See cp-abi.h.  */
 193
 194 struct type *
 195 cplus_typeid_type (struct gdbarch *gdbarch)
 196 {
 197   if (current_cp_abi.get_typeid_type == NULL)
 198     error (_("GDB cannot find the type for 'typeid' on this target"));
 199   return (*current_cp_abi.get_typeid_type) (gdbarch);
 200 }
 201
 202 /* See cp-abi.h.  */
 203
 204 struct type *
 205 cplus_type_from_type_info (struct value *value)
 206 {
 207   if (current_cp_abi.get_type_from_type_info == NULL)
 208     error (_("GDB cannot find the type from a std::type_info on this target"));
 209   return (*current_cp_abi.get_type_from_type_info) (value);
 210 }
 211
 212 int
 213 cp_pass_by_reference (struct type *type)
 214 {
 215   if ((current_cp_abi.pass_by_reference) == NULL)
 216     return 0;
 217   return (*current_cp_abi.pass_by_reference) (type);
 218 }
 219
 220 /* Set the current C++ ABI to SHORT_NAME.  */
 221
 222 static int
 223 switch_to_cp_abi (const char *short_name)
 224 {
 225   struct cp_abi_ops *abi;
 226
 227   abi = find_cp_abi (short_name);
 228   if (abi == NULL)
 229     return 0;
 230
 231   current_cp_abi = *abi;
 232   return 1;
 233 }
 234
 235 /* Add ABI to the list of supported C++ ABI's.  */
 236
 237 int
 238 register_cp_abi (struct cp_abi_ops *abi)
 239 {
 240   if (num_cp_abis == CP_ABI_MAX)
 241     internal_error (__FILE__, __LINE__,
 242                     _("Too many C++ ABIs, please increase "
 243                       "CP_ABI_MAX in cp-abi.c"));
 244
 245   cp_abis[num_cp_abis++] = abi;
 246
 247   return 1;
 248 }
 249
 250 /* Set the ABI to use in "auto" mode to SHORT_NAME.  */
 251
 252 void
 253 set_cp_abi_as_auto_default (const char *short_name)
 254 {
 255   char *new_longname, *new_doc;
 256   struct cp_abi_ops *abi = find_cp_abi (short_name);
 257
 258   if (abi == NULL)
 259     internal_error (__FILE__, __LINE__,
 260                     _("Cannot find C++ ABI \"%s\" to set it as auto default."),
 261                     short_name);
 262
 263   if (auto_cp_abi.longname != NULL)
 264     xfree ((char *) auto_cp_abi.longname);
 265   if (auto_cp_abi.doc != NULL)
 266     xfree ((char *) auto_cp_abi.doc);
 267
 268   auto_cp_abi = *abi;
 269
 270   auto_cp_abi.shortname = "auto";
 271   new_longname = xstrprintf ("currently \"%s\"", abi->shortname);
 272   auto_cp_abi.longname = new_longname;
 273
 274   new_doc = xstrprintf ("Automatically selected; currently \"%s\"",
 275              abi->shortname);
 276   auto_cp_abi.doc = new_doc;
 277
 278   /* Since we copy the current ABI into current_cp_abi instead of
 279      using a pointer, if auto is currently the default, we need to
 280      reset it.  */
 281   if (strcmp (current_cp_abi.shortname, "auto") == 0)
 282     switch_to_cp_abi ("auto");
 283 }
 284
 285 /* Return the ABI operations associated with SHORT_NAME.  */
 286
 287 static struct cp_abi_ops *
 288 find_cp_abi (const char *short_name)
 289 {
 290   int i;
 291
 292   for (i = 0; i < num_cp_abis; i++)
 293     if (strcmp (cp_abis[i]->shortname, short_name) == 0)
 294       return cp_abis[i];
 295
 296   return NULL;
 297 }
 298
 299 /* Display the list of registered C++ ABIs.  */
 300
 301 static void
 302 list_cp_abis (int from_tty)
 303 {
 304   struct ui_out *uiout = current_uiout;
 305   struct cleanup *cleanup_chain;
 306   int i;
 307
 308   ui_out_text (uiout, "The available C++ ABIs are:\n");
 309   cleanup_chain = make_cleanup_ui_out_tuple_begin_end (uiout,
 310                                                        "cp-abi-list");
 311   for (i = 0; i < num_cp_abis; i++)
 312     {
 313       char pad[14];
 314       int padcount;
 315
 316       ui_out_text (uiout, "  ");
 317       ui_out_field_string (uiout, "cp-abi", cp_abis[i]->shortname);
 318
 319       padcount = 16 - 2 - strlen (cp_abis[i]->shortname);
 320       pad[padcount] = 0;
 321       while (padcount > 0)
 322         pad[--padcount] = ' ';
 323       ui_out_text (uiout, pad);
 324
 325       ui_out_field_string (uiout, "doc", cp_abis[i]->doc);
 326       ui_out_text (uiout, "\n");
 327     }
 328   do_cleanups (cleanup_chain);
 329 }
 330
 331 /* Set the current C++ ABI, or display the list of options if no
 332    argument is given.  */
 333
 334 static void
 335 set_cp_abi_cmd (char *args, int from_tty)
 336 {
 337   if (args == NULL)
 338     {
 339       list_cp_abis (from_tty);
 340       return;
 341     }
 342
 343   if (!switch_to_cp_abi (args))
 344     error (_("Could not find \"%s\" in ABI list"), args);
 345 }
 346
 347 /* A completion function for "set cp-abi".  */
 348
 349 static VEC (char_ptr) *
 350 cp_abi_completer (struct cmd_list_element *ignore,
 351                   const char *text, const char *word)
 352 {
 353   static const char **cp_abi_names;
 354
 355   if (cp_abi_names == NULL)
 356     {
 357       int i;
 358
 359       cp_abi_names = XNEWVEC (const char *, num_cp_abis + 1);
 360       for (i = 0; i < num_cp_abis; ++i)
 361         cp_abi_names[i] = cp_abis[i]->shortname;
 362       cp_abi_names[i] = NULL;
 363     }
 364
 365   return complete_on_enum (cp_abi_names, text, word);
 366 }
 367
 368 /* Show the currently selected C++ ABI.  */
 369
 370 static void
 371 show_cp_abi_cmd (char *args, int from_tty)
 372 {
 373   struct ui_out *uiout = current_uiout;
 374
 375   ui_out_text (uiout, "The currently selected C++ ABI is \"");
 376
 377   ui_out_field_string (uiout, "cp-abi", current_cp_abi.shortname);
 378   ui_out_text (uiout, "\" (");
 379   ui_out_field_string (uiout, "longname", current_cp_abi.longname);
 380   ui_out_text (uiout, ").\n");
 381 }
 382
 383 extern initialize_file_ftype _initialize_cp_abi; /* -Wmissing-prototypes */
 384
 385 void
 386 _initialize_cp_abi (void)
 387 {
 388   struct cmd_list_element *c;
 389
 390   register_cp_abi (&auto_cp_abi);
 391   switch_to_cp_abi ("auto");
 392
 393   c = add_cmd ("cp-abi", class_obscure, set_cp_abi_cmd, _("\
 394 Set the ABI used for inspecting C++ objects.\n\
 395 \"set cp-abi\" with no arguments will list the available ABIs."),
 396                &setlist);
 397   set_cmd_completer (c, cp_abi_completer);
 398
 399   add_cmd ("cp-abi", class_obscure, show_cp_abi_cmd,
 400            _("Show the ABI used for inspecting C++ objects."),
 401            &showlist);
 402 }