gdb/cp-abi.c

   1 /* Generic code for supporting multiple C++ ABI's
   2
   3    Copyright (C) 2001-2015 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 "gdbcmd.h"
  25 #include "ui-out.h"
  26 static struct cp_abi_ops *find_cp_abi (const char *short_name);
  27
  28 static struct cp_abi_ops current_cp_abi = { "", NULL };
  29 static struct cp_abi_ops auto_cp_abi = { "auto", NULL };
  30
  31 #define CP_ABI_MAX 8
  32 static struct cp_abi_ops *cp_abis[CP_ABI_MAX];
  33 static int num_cp_abis = 0;
  34
  35 enum ctor_kinds
  36 is_constructor_name (const char *name)
  37 {
  38   if ((current_cp_abi.is_constructor_name) == NULL)
  39     error (_("ABI doesn't define required function is_constructor_name"));
  40   return (*current_cp_abi.is_constructor_name) (name);
  41 }
  42
  43 enum dtor_kinds
  44 is_destructor_name (const char *name)
  45 {
  46   if ((current_cp_abi.is_destructor_name) == NULL)
  47     error (_("ABI doesn't define required function is_destructor_name"));
  48   return (*current_cp_abi.is_destructor_name) (name);
  49 }
  50
  51 int
  52 is_vtable_name (const char *name)
  53 {
  54   if ((current_cp_abi.is_vtable_name) == NULL)
  55     error (_("ABI doesn't define required function is_vtable_name"));
  56   return (*current_cp_abi.is_vtable_name) (name);
  57 }
  58
  59 int
  60 is_operator_name (const char *name)
  61 {
  62   if ((current_cp_abi.is_operator_name) == NULL)
  63     error (_("ABI doesn't define required function is_operator_name"));
  64   return (*current_cp_abi.is_operator_name) (name);
  65 }
  66
  67 int
  68 baseclass_offset (struct type *type, int index, const gdb_byte *valaddr,
  69                   int embedded_offset, CORE_ADDR address,
  70                   const struct value *val)
  71 {
  72   volatile struct gdb_exception ex;
  73   int res = 0;
  74
  75   gdb_assert (current_cp_abi.baseclass_offset != NULL);
  76
  77   TRY_CATCH (ex, RETURN_MASK_ERROR)
  78     {
  79       res = (*current_cp_abi.baseclass_offset) (type, index, valaddr,
  80                                                 embedded_offset,
  81                                                 address, val);
  82     }
  83   if (ex.reason < 0)
  84     {
  85       if (ex.error != NOT_AVAILABLE_ERROR)
  86         throw_exception (ex);
  87
  88       throw_error (NOT_AVAILABLE_ERROR,
  89                    _("Cannot determine virtual baseclass offset "
  90                      "of incomplete object"));
  91     }
  92
  93   return res;
  94 }
  95
  96 struct value *
  97 value_virtual_fn_field (struct value **arg1p,
  98                         struct fn_field *f, int j,
  99                         struct type *type, int offset)
 100 {
 101   if ((current_cp_abi.virtual_fn_field) == NULL)
 102     return NULL;
 103   return (*current_cp_abi.virtual_fn_field) (arg1p, f, j,
 104                                              type, offset);
 105 }
 106
 107 struct type *
 108 value_rtti_type (struct value *v, int *full,
 109                  int *top, int *using_enc)
 110 {
 111   struct type *ret = NULL;
 112   volatile struct gdb_exception e;
 113
 114   if ((current_cp_abi.rtti_type) == NULL)
 115     return NULL;
 116   TRY_CATCH (e, RETURN_MASK_ERROR)
 117     {
 118       ret = (*current_cp_abi.rtti_type) (v, full, top, using_enc);
 119     }
 120   if (e.reason < 0)
 121     return NULL;
 122   return ret;
 123 }
 124
 125 void
 126 cplus_print_method_ptr (const gdb_byte *contents,
 127                         struct type *type,
 128                         struct ui_file *stream)
 129 {
 130   if (current_cp_abi.print_method_ptr == NULL)
 131     error (_("GDB does not support pointers to methods on this target"));
 132   (*current_cp_abi.print_method_ptr) (contents, type, stream);
 133 }
 134
 135 int
 136 cplus_method_ptr_size (struct type *to_type)
 137 {
 138   if (current_cp_abi.method_ptr_size == NULL)
 139     error (_("GDB does not support pointers to methods on this target"));
 140   return (*current_cp_abi.method_ptr_size) (to_type);
 141 }
 142
 143 void
 144 cplus_make_method_ptr (struct type *type, gdb_byte *contents,
 145                        CORE_ADDR value, int is_virtual)
 146 {
 147   if (current_cp_abi.make_method_ptr == NULL)
 148     error (_("GDB does not support pointers to methods on this target"));
 149   (*current_cp_abi.make_method_ptr) (type, contents, value, is_virtual);
 150 }
 151
 152 CORE_ADDR
 153 cplus_skip_trampoline (struct frame_info *frame,
 154                        CORE_ADDR stop_pc)
 155 {
 156   if (current_cp_abi.skip_trampoline == NULL)
 157     return 0;
 158   return (*current_cp_abi.skip_trampoline) (frame, stop_pc);
 159 }
 160
 161 struct value *
 162 cplus_method_ptr_to_value (struct value **this_p,
 163                            struct value *method_ptr)
 164 {
 165   if (current_cp_abi.method_ptr_to_value == NULL)
 166     error (_("GDB does not support pointers to methods on this target"));
 167   return (*current_cp_abi.method_ptr_to_value) (this_p, method_ptr);
 168 }
 169
 170 /* See cp-abi.h.  */
 171
 172 void
 173 cplus_print_vtable (struct value *value)
 174 {
 175   if (current_cp_abi.print_vtable == NULL)
 176     error (_("GDB cannot print the vtable on this target"));
 177   (*current_cp_abi.print_vtable) (value);
 178 }
 179
 180 /* See cp-abi.h.  */
 181
 182 struct value *
 183 cplus_typeid (struct value *value)
 184 {
 185   if (current_cp_abi.get_typeid == NULL)
 186     error (_("GDB cannot find the typeid on this target"));
 187   return (*current_cp_abi.get_typeid) (value);
 188 }
 189
 190 /* See cp-abi.h.  */
 191
 192 struct type *
 193 cplus_typeid_type (struct gdbarch *gdbarch)
 194 {
 195   if (current_cp_abi.get_typeid_type == NULL)
 196     error (_("GDB cannot find the type for 'typeid' on this target"));
 197   return (*current_cp_abi.get_typeid_type) (gdbarch);
 198 }
 199
 200 /* See cp-abi.h.  */
 201
 202 struct type *
 203 cplus_type_from_type_info (struct value *value)
 204 {
 205   if (current_cp_abi.get_type_from_type_info == NULL)
 206     error (_("GDB cannot find the type from a std::type_info on this target"));
 207   return (*current_cp_abi.get_type_from_type_info) (value);
 208 }
 209
 210 /* See cp-abi.h.  */
 211
 212 char *
 213 cplus_typename_from_type_info (struct value *value)
 214 {
 215   if (current_cp_abi.get_typename_from_type_info == NULL)
 216     error (_("GDB cannot find the type name "
 217              "from a std::type_info on this target"));
 218   return (*current_cp_abi.get_typename_from_type_info) (value);
 219 }
 220
 221 int
 222 cp_pass_by_reference (struct type *type)
 223 {
 224   if ((current_cp_abi.pass_by_reference) == NULL)
 225     return 0;
 226   return (*current_cp_abi.pass_by_reference) (type);
 227 }
 228
 229 /* Set the current C++ ABI to SHORT_NAME.  */
 230
 231 static int
 232 switch_to_cp_abi (const char *short_name)
 233 {
 234   struct cp_abi_ops *abi;
 235
 236   abi = find_cp_abi (short_name);
 237   if (abi == NULL)
 238     return 0;
 239
 240   current_cp_abi = *abi;
 241   return 1;
 242 }
 243
 244 /* Add ABI to the list of supported C++ ABI's.  */
 245
 246 int
 247 register_cp_abi (struct cp_abi_ops *abi)
 248 {
 249   if (num_cp_abis == CP_ABI_MAX)
 250     internal_error (__FILE__, __LINE__,
 251                     _("Too many C++ ABIs, please increase "
 252                       "CP_ABI_MAX in cp-abi.c"));
 253
 254   cp_abis[num_cp_abis++] = abi;
 255
 256   return 1;
 257 }
 258
 259 /* Set the ABI to use in "auto" mode to SHORT_NAME.  */
 260
 261 void
 262 set_cp_abi_as_auto_default (const char *short_name)
 263 {
 264   char *new_longname, *new_doc;
 265   struct cp_abi_ops *abi = find_cp_abi (short_name);
 266
 267   if (abi == NULL)
 268     internal_error (__FILE__, __LINE__,
 269                     _("Cannot find C++ ABI \"%s\" to set it as auto default."),
 270                     short_name);
 271
 272   if (auto_cp_abi.longname != NULL)
 273     xfree ((char *) auto_cp_abi.longname);
 274   if (auto_cp_abi.doc != NULL)
 275     xfree ((char *) auto_cp_abi.doc);
 276
 277   auto_cp_abi = *abi;
 278
 279   auto_cp_abi.shortname = "auto";
 280   new_longname = xstrprintf ("currently \"%s\"", abi->shortname);
 281   auto_cp_abi.longname = new_longname;
 282
 283   new_doc = xstrprintf ("Automatically selected; currently \"%s\"",
 284              abi->shortname);
 285   auto_cp_abi.doc = new_doc;
 286
 287   /* Since we copy the current ABI into current_cp_abi instead of
 288      using a pointer, if auto is currently the default, we need to
 289      reset it.  */
 290   if (strcmp (current_cp_abi.shortname, "auto") == 0)
 291     switch_to_cp_abi ("auto");
 292 }
 293
 294 /* Return the ABI operations associated with SHORT_NAME.  */
 295
 296 static struct cp_abi_ops *
 297 find_cp_abi (const char *short_name)
 298 {
 299   int i;
 300
 301   for (i = 0; i < num_cp_abis; i++)
 302     if (strcmp (cp_abis[i]->shortname, short_name) == 0)
 303       return cp_abis[i];
 304
 305   return NULL;
 306 }
 307
 308 /* Display the list of registered C++ ABIs.  */
 309
 310 static void
 311 list_cp_abis (int from_tty)
 312 {
 313   struct ui_out *uiout = current_uiout;
 314   struct cleanup *cleanup_chain;
 315   int i;
 316
 317   ui_out_text (uiout, "The available C++ ABIs are:\n");
 318   cleanup_chain = make_cleanup_ui_out_tuple_begin_end (uiout,
 319                                                        "cp-abi-list");
 320   for (i = 0; i < num_cp_abis; i++)
 321     {
 322       char pad[14];
 323       int padcount;
 324
 325       ui_out_text (uiout, "  ");
 326       ui_out_field_string (uiout, "cp-abi", cp_abis[i]->shortname);
 327
 328       padcount = 16 - 2 - strlen (cp_abis[i]->shortname);
 329       pad[padcount] = 0;
 330       while (padcount > 0)
 331         pad[--padcount] = ' ';
 332       ui_out_text (uiout, pad);
 333
 334       ui_out_field_string (uiout, "doc", cp_abis[i]->doc);
 335       ui_out_text (uiout, "\n");
 336     }
 337   do_cleanups (cleanup_chain);
 338 }
 339
 340 /* Set the current C++ ABI, or display the list of options if no
 341    argument is given.  */
 342
 343 static void
 344 set_cp_abi_cmd (char *args, int from_tty)
 345 {
 346   if (args == NULL)
 347     {
 348       list_cp_abis (from_tty);
 349       return;
 350     }
 351
 352   if (!switch_to_cp_abi (args))
 353     error (_("Could not find \"%s\" in ABI list"), args);
 354 }
 355
 356 /* A completion function for "set cp-abi".  */
 357
 358 static VEC (char_ptr) *
 359 cp_abi_completer (struct cmd_list_element *ignore,
 360                   const char *text, const char *word)
 361 {
 362   static const char **cp_abi_names;
 363
 364   if (cp_abi_names == NULL)
 365     {
 366       int i;
 367
 368       cp_abi_names = XNEWVEC (const char *, num_cp_abis + 1);
 369       for (i = 0; i < num_cp_abis; ++i)
 370         cp_abi_names[i] = cp_abis[i]->shortname;
 371       cp_abi_names[i] = NULL;
 372     }
 373
 374   return complete_on_enum (cp_abi_names, text, word);
 375 }
 376
 377 /* Show the currently selected C++ ABI.  */
 378
 379 static void
 380 show_cp_abi_cmd (char *args, int from_tty)
 381 {
 382   struct ui_out *uiout = current_uiout;
 383
 384   ui_out_text (uiout, "The currently selected C++ ABI is \"");
 385
 386   ui_out_field_string (uiout, "cp-abi", current_cp_abi.shortname);
 387   ui_out_text (uiout, "\" (");
 388   ui_out_field_string (uiout, "longname", current_cp_abi.longname);
 389   ui_out_text (uiout, ").\n");
 390 }
 391
 392 extern initialize_file_ftype _initialize_cp_abi; /* -Wmissing-prototypes */
 393
 394 void
 395 _initialize_cp_abi (void)
 396 {
 397   struct cmd_list_element *c;
 398
 399   register_cp_abi (&auto_cp_abi);
 400   switch_to_cp_abi ("auto");
 401
 402   c = add_cmd ("cp-abi", class_obscure, set_cp_abi_cmd, _("\
 403 Set the ABI used for inspecting C++ objects.\n\
 404 \"set cp-abi\" with no arguments will list the available ABIs."),
 405                &setlist);
 406   set_cmd_completer (c, cp_abi_completer);
 407
 408   add_cmd ("cp-abi", class_obscure, show_cp_abi_cmd,
 409            _("Show the ABI used for inspecting C++ objects."),
 410            &showlist);
 411 }