gdb/cp-abi.c

   1 /* Generic code for supporting multiple C++ ABI's
   2
   3    Copyright (C) 2001-2014 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 <string.h>
  28
  29 static struct cp_abi_ops *find_cp_abi (const char *short_name);
  30
  31 static struct cp_abi_ops current_cp_abi = { "", NULL };
  32 static struct cp_abi_ops auto_cp_abi = { "auto", NULL };
  33
  34 #define CP_ABI_MAX 8
  35 static struct cp_abi_ops *cp_abis[CP_ABI_MAX];
  36 static int num_cp_abis = 0;
  37
  38 enum ctor_kinds
  39 is_constructor_name (const char *name)
  40 {
  41   if ((current_cp_abi.is_constructor_name) == NULL)
  42     error (_("ABI doesn't define required function is_constructor_name"));
  43   return (*current_cp_abi.is_constructor_name) (name);
  44 }
  45
  46 enum dtor_kinds
  47 is_destructor_name (const char *name)
  48 {
  49   if ((current_cp_abi.is_destructor_name) == NULL)
  50     error (_("ABI doesn't define required function is_destructor_name"));
  51   return (*current_cp_abi.is_destructor_name) (name);
  52 }
  53
  54 int
  55 is_vtable_name (const char *name)
  56 {
  57   if ((current_cp_abi.is_vtable_name) == NULL)
  58     error (_("ABI doesn't define required function is_vtable_name"));
  59   return (*current_cp_abi.is_vtable_name) (name);
  60 }
  61
  62 int
  63 is_operator_name (const char *name)
  64 {
  65   if ((current_cp_abi.is_operator_name) == NULL)
  66     error (_("ABI doesn't define required function is_operator_name"));
  67   return (*current_cp_abi.is_operator_name) (name);
  68 }
  69
  70 int
  71 baseclass_offset (struct type *type, int index, const gdb_byte *valaddr,
  72                   int embedded_offset, CORE_ADDR address,
  73                   const struct value *val)
  74 {
  75   volatile struct gdb_exception ex;
  76   int res = 0;
  77
  78   gdb_assert (current_cp_abi.baseclass_offset != NULL);
  79
  80   TRY_CATCH (ex, RETURN_MASK_ERROR)
  81     {
  82       res = (*current_cp_abi.baseclass_offset) (type, index, valaddr,
  83                                                 embedded_offset,
  84                                                 address, val);
  85     }
  86
  87   if (ex.reason < 0 && ex.error == NOT_AVAILABLE_ERROR)
  88     throw_error (NOT_AVAILABLE_ERROR,
  89                  _("Cannot determine virtual baseclass offset "
  90                    "of incomplete object"));
  91   else if (ex.reason < 0)
  92     throw_exception (ex);
  93   else
  94     return res;
  95 }
  96
  97 struct value *
  98 value_virtual_fn_field (struct value **arg1p,
  99                         struct fn_field *f, int j,
 100                         struct type *type, int offset)
 101 {
 102   if ((current_cp_abi.virtual_fn_field) == NULL)
 103     return NULL;
 104   return (*current_cp_abi.virtual_fn_field) (arg1p, f, j,
 105                                              type, offset);
 106 }
 107
 108 struct type *
 109 value_rtti_type (struct value *v, int *full,
 110                  int *top, int *using_enc)
 111 {
 112   struct type *ret = NULL;
 113   volatile struct gdb_exception e;
 114
 115   if ((current_cp_abi.rtti_type) == NULL)
 116     return NULL;
 117   TRY_CATCH (e, RETURN_MASK_ERROR)
 118     {
 119       ret = (*current_cp_abi.rtti_type) (v, full, top, using_enc);
 120     }
 121   if (e.reason < 0)
 122     return NULL;
 123   return ret;
 124 }
 125
 126 void
 127 cplus_print_method_ptr (const gdb_byte *contents,
 128                         struct type *type,
 129                         struct ui_file *stream)
 130 {
 131   if (current_cp_abi.print_method_ptr == NULL)
 132     error (_("GDB does not support pointers to methods on this target"));
 133   (*current_cp_abi.print_method_ptr) (contents, type, stream);
 134 }
 135
 136 int
 137 cplus_method_ptr_size (struct type *to_type)
 138 {
 139   if (current_cp_abi.method_ptr_size == NULL)
 140     error (_("GDB does not support pointers to methods on this target"));
 141   return (*current_cp_abi.method_ptr_size) (to_type);
 142 }
 143
 144 void
 145 cplus_make_method_ptr (struct type *type, gdb_byte *contents,
 146                        CORE_ADDR value, int is_virtual)
 147 {
 148   if (current_cp_abi.make_method_ptr == NULL)
 149     error (_("GDB does not support pointers to methods on this target"));
 150   (*current_cp_abi.make_method_ptr) (type, contents, value, is_virtual);
 151 }
 152
 153 CORE_ADDR
 154 cplus_skip_trampoline (struct frame_info *frame,
 155                        CORE_ADDR stop_pc)
 156 {
 157   if (current_cp_abi.skip_trampoline == NULL)
 158     return 0;
 159   return (*current_cp_abi.skip_trampoline) (frame, stop_pc);
 160 }
 161
 162 struct value *
 163 cplus_method_ptr_to_value (struct value **this_p,
 164                            struct value *method_ptr)
 165 {
 166   if (current_cp_abi.method_ptr_to_value == NULL)
 167     error (_("GDB does not support pointers to methods on this target"));
 168   return (*current_cp_abi.method_ptr_to_value) (this_p, method_ptr);
 169 }
 170
 171 /* See cp-abi.h.  */
 172
 173 void
 174 cplus_print_vtable (struct value *value)
 175 {
 176   if (current_cp_abi.print_vtable == NULL)
 177     error (_("GDB cannot print the vtable on this target"));
 178   (*current_cp_abi.print_vtable) (value);
 179 }
 180
 181 /* See cp-abi.h.  */
 182
 183 struct value *
 184 cplus_typeid (struct value *value)
 185 {
 186   if (current_cp_abi.get_typeid == NULL)
 187     error (_("GDB cannot find the typeid on this target"));
 188   return (*current_cp_abi.get_typeid) (value);
 189 }
 190
 191 /* See cp-abi.h.  */
 192
 193 struct type *
 194 cplus_typeid_type (struct gdbarch *gdbarch)
 195 {
 196   if (current_cp_abi.get_typeid_type == NULL)
 197     error (_("GDB cannot find the type for 'typeid' on this target"));
 198   return (*current_cp_abi.get_typeid_type) (gdbarch);
 199 }
 200
 201 /* See cp-abi.h.  */
 202
 203 struct type *
 204 cplus_type_from_type_info (struct value *value)
 205 {
 206   if (current_cp_abi.get_type_from_type_info == NULL)
 207     error (_("GDB cannot find the type from a std::type_info on this target"));
 208   return (*current_cp_abi.get_type_from_type_info) (value);
 209 }
 210
 211 /* See cp-abi.h.  */
 212
 213 char *
 214 cplus_typename_from_type_info (struct value *value)
 215 {
 216   if (current_cp_abi.get_typename_from_type_info == NULL)
 217     error (_("GDB cannot find the type name "
 218              "from a std::type_info on this target"));
 219   return (*current_cp_abi.get_typename_from_type_info) (value);
 220 }
 221
 222 int
 223 cp_pass_by_reference (struct type *type)
 224 {
 225   if ((current_cp_abi.pass_by_reference) == NULL)
 226     return 0;
 227   return (*current_cp_abi.pass_by_reference) (type);
 228 }
 229
 230 /* Set the current C++ ABI to SHORT_NAME.  */
 231
 232 static int
 233 switch_to_cp_abi (const char *short_name)
 234 {
 235   struct cp_abi_ops *abi;
 236
 237   abi = find_cp_abi (short_name);
 238   if (abi == NULL)
 239     return 0;
 240
 241   current_cp_abi = *abi;
 242   return 1;
 243 }
 244
 245 /* Add ABI to the list of supported C++ ABI's.  */
 246
 247 int
 248 register_cp_abi (struct cp_abi_ops *abi)
 249 {
 250   if (num_cp_abis == CP_ABI_MAX)
 251     internal_error (__FILE__, __LINE__,
 252                     _("Too many C++ ABIs, please increase "
 253                       "CP_ABI_MAX in cp-abi.c"));
 254
 255   cp_abis[num_cp_abis++] = abi;
 256
 257   return 1;
 258 }
 259
 260 /* Set the ABI to use in "auto" mode to SHORT_NAME.  */
 261
 262 void
 263 set_cp_abi_as_auto_default (const char *short_name)
 264 {
 265   char *new_longname, *new_doc;
 266   struct cp_abi_ops *abi = find_cp_abi (short_name);
 267
 268   if (abi == NULL)
 269     internal_error (__FILE__, __LINE__,
 270                     _("Cannot find C++ ABI \"%s\" to set it as auto default."),
 271                     short_name);
 272
 273   if (auto_cp_abi.longname != NULL)
 274     xfree ((char *) auto_cp_abi.longname);
 275   if (auto_cp_abi.doc != NULL)
 276     xfree ((char *) auto_cp_abi.doc);
 277
 278   auto_cp_abi = *abi;
 279
 280   auto_cp_abi.shortname = "auto";
 281   new_longname = xstrprintf ("currently \"%s\"", abi->shortname);
 282   auto_cp_abi.longname = new_longname;
 283
 284   new_doc = xstrprintf ("Automatically selected; currently \"%s\"",
 285              abi->shortname);
 286   auto_cp_abi.doc = new_doc;
 287
 288   /* Since we copy the current ABI into current_cp_abi instead of
 289      using a pointer, if auto is currently the default, we need to
 290      reset it.  */
 291   if (strcmp (current_cp_abi.shortname, "auto") == 0)
 292     switch_to_cp_abi ("auto");
 293 }
 294
 295 /* Return the ABI operations associated with SHORT_NAME.  */
 296
 297 static struct cp_abi_ops *
 298 find_cp_abi (const char *short_name)
 299 {
 300   int i;
 301
 302   for (i = 0; i < num_cp_abis; i++)
 303     if (strcmp (cp_abis[i]->shortname, short_name) == 0)
 304       return cp_abis[i];
 305
 306   return NULL;
 307 }
 308
 309 /* Display the list of registered C++ ABIs.  */
 310
 311 static void
 312 list_cp_abis (int from_tty)
 313 {
 314   struct ui_out *uiout = current_uiout;
 315   struct cleanup *cleanup_chain;
 316   int i;
 317
 318   ui_out_text (uiout, "The available C++ ABIs are:\n");
 319   cleanup_chain = make_cleanup_ui_out_tuple_begin_end (uiout,
 320                                                        "cp-abi-list");
 321   for (i = 0; i < num_cp_abis; i++)
 322     {
 323       char pad[14];
 324       int padcount;
 325
 326       ui_out_text (uiout, "  ");
 327       ui_out_field_string (uiout, "cp-abi", cp_abis[i]->shortname);
 328
 329       padcount = 16 - 2 - strlen (cp_abis[i]->shortname);
 330       pad[padcount] = 0;
 331       while (padcount > 0)
 332         pad[--padcount] = ' ';
 333       ui_out_text (uiout, pad);
 334
 335       ui_out_field_string (uiout, "doc", cp_abis[i]->doc);
 336       ui_out_text (uiout, "\n");
 337     }
 338   do_cleanups (cleanup_chain);
 339 }
 340
 341 /* Set the current C++ ABI, or display the list of options if no
 342    argument is given.  */
 343
 344 static void
 345 set_cp_abi_cmd (char *args, int from_tty)
 346 {
 347   if (args == NULL)
 348     {
 349       list_cp_abis (from_tty);
 350       return;
 351     }
 352
 353   if (!switch_to_cp_abi (args))
 354     error (_("Could not find \"%s\" in ABI list"), args);
 355 }
 356
 357 /* A completion function for "set cp-abi".  */
 358
 359 static VEC (char_ptr) *
 360 cp_abi_completer (struct cmd_list_element *ignore,
 361                   const char *text, const char *word)
 362 {
 363   static const char **cp_abi_names;
 364
 365   if (cp_abi_names == NULL)
 366     {
 367       int i;
 368
 369       cp_abi_names = XNEWVEC (const char *, num_cp_abis + 1);
 370       for (i = 0; i < num_cp_abis; ++i)
 371         cp_abi_names[i] = cp_abis[i]->shortname;
 372       cp_abi_names[i] = NULL;
 373     }
 374
 375   return complete_on_enum (cp_abi_names, text, word);
 376 }
 377
 378 /* Show the currently selected C++ ABI.  */
 379
 380 static void
 381 show_cp_abi_cmd (char *args, int from_tty)
 382 {
 383   struct ui_out *uiout = current_uiout;
 384
 385   ui_out_text (uiout, "The currently selected C++ ABI is \"");
 386
 387   ui_out_field_string (uiout, "cp-abi", current_cp_abi.shortname);
 388   ui_out_text (uiout, "\" (");
 389   ui_out_field_string (uiout, "longname", current_cp_abi.longname);
 390   ui_out_text (uiout, ").\n");
 391 }
 392
 393 extern initialize_file_ftype _initialize_cp_abi; /* -Wmissing-prototypes */
 394
 395 void
 396 _initialize_cp_abi (void)
 397 {
 398   struct cmd_list_element *c;
 399
 400   register_cp_abi (&auto_cp_abi);
 401   switch_to_cp_abi ("auto");
 402
 403   c = add_cmd ("cp-abi", class_obscure, set_cp_abi_cmd, _("\
 404 Set the ABI used for inspecting C++ objects.\n\
 405 \"set cp-abi\" with no arguments will list the available ABIs."),
 406                &setlist);
 407   set_cmd_completer (c, cp_abi_completer);
 408
 409   add_cmd ("cp-abi", class_obscure, show_cp_abi_cmd,
 410            _("Show the ABI used for inspecting C++ objects."),
 411            &showlist);
 412 }