aboutsummaryrefslogtreecommitdiff
path: root/gdb/c-varobj.c
blob: 56354e5f06656a6f280a744a0cdc51192a982664 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
/* varobj support for C and C++.

   Copyright (C) 1999-2020 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "value.h"
#include "varobj.h"
#include "gdbthread.h"
#include "valprint.h"

static void cplus_class_num_children (struct type *type, int children[3]);

/* The names of varobjs representing anonymous structs or unions.  */
#define ANONYMOUS_STRUCT_NAME _("<anonymous struct>")
#define ANONYMOUS_UNION_NAME _("<anonymous union>")

/* Does CHILD represent a child with no name?  This happens when
   the child is an anonymous struct or union and it has no field name
   in its parent variable.

   This has already been determined by *_describe_child. The easiest
   thing to do is to compare the child's name with ANONYMOUS_*_NAME.  */

bool
varobj_is_anonymous_child (const struct varobj *child)
{
  return (child->name == ANONYMOUS_STRUCT_NAME
	  || child->name == ANONYMOUS_UNION_NAME);
}

/* Given the value and the type of a variable object,
   adjust the value and type to those necessary
   for getting children of the variable object.
   This includes dereferencing top-level references
   to all types and dereferencing pointers to
   structures.

   If LOOKUP_ACTUAL_TYPE is set the enclosing type of the
   value will be fetched and if it differs from static type
   the value will be casted to it.

   Both TYPE and *TYPE should be non-null.  VALUE
   can be null if we want to only translate type.
   *VALUE can be null as well -- if the parent
   value is not known.

   If WAS_PTR is not NULL, set *WAS_PTR to 0 or 1
   depending on whether pointer was dereferenced
   in this function.  */

static void
adjust_value_for_child_access (struct value **value,
				  struct type **type,
				  int *was_ptr,
				  int lookup_actual_type)
{
  gdb_assert (type && *type);

  if (was_ptr)
    *was_ptr = 0;

  *type = check_typedef (*type);
  
  /* The type of value stored in varobj, that is passed
     to us, is already supposed to be
     reference-stripped.  */

  gdb_assert (!TYPE_IS_REFERENCE (*type));

  /* Pointers to structures are treated just like
     structures when accessing children.  Don't
     dereference pointers to other types.  */
  if ((*type)->code () == TYPE_CODE_PTR)
    {
      struct type *target_type = get_target_type (*type);
      if (target_type->code () == TYPE_CODE_STRUCT
	  || target_type->code () == TYPE_CODE_UNION)
	{
	  if (value && *value)
	    {

	      try
		{
		  *value = value_ind (*value);
		}

	      catch (const gdb_exception_error &except)
		{
		  *value = NULL;
		}
	    }
	  *type = target_type;
	  if (was_ptr)
	    *was_ptr = 1;
	}
    }

  /* The 'get_target_type' function calls check_typedef on
     result, so we can immediately check type code.  No
     need to call check_typedef here.  */

  /* Access a real type of the value (if necessary and possible).  */
  if (value && *value && lookup_actual_type)
    {
      struct type *enclosing_type;
      int real_type_found = 0;

      enclosing_type = value_actual_type (*value, 1, &real_type_found);
      if (real_type_found)
        {
          *type = enclosing_type;
          *value = value_cast (enclosing_type, *value);
        }
    }
}

/* Is VAR a path expression parent, i.e., can it be used to construct
   a valid path expression?  */

static bool
c_is_path_expr_parent (const struct varobj *var)
{
  struct type *type;

  /* "Fake" children are not path_expr parents.  */
  if (CPLUS_FAKE_CHILD (var))
    return false;

  type = varobj_get_gdb_type (var);

  /* Anonymous unions and structs are also not path_expr parents.  */
  if ((type->code () == TYPE_CODE_STRUCT
       || type->code () == TYPE_CODE_UNION)
      && type->name () == NULL)
    {
      const struct varobj *parent = var->parent;

      while (parent != NULL && CPLUS_FAKE_CHILD (parent))
	parent = parent->parent;

      if (parent != NULL)
	{
	  struct type *parent_type;
	  int was_ptr;

	  parent_type = varobj_get_value_type (parent);
	  adjust_value_for_child_access (NULL, &parent_type, &was_ptr, 0);

	  if (parent_type->code () == TYPE_CODE_STRUCT
	      || parent_type->code () == TYPE_CODE_UNION)
	    {
	      const char *field_name;

	      gdb_assert (var->index < parent_type->num_fields ());
	      field_name = TYPE_FIELD_NAME (parent_type, var->index);
	      return !(field_name == NULL || *field_name == '\0');
	    }
	}

      return false;
    }

  return true;
}

/* C */

static int
c_number_of_children (const struct varobj *var)
{
  struct type *type = varobj_get_value_type (var);
  int children = 0;
  struct type *target;

  adjust_value_for_child_access (NULL, &type, NULL, 0);
  target = get_target_type (type);

  switch (type->code ())
    {
    case TYPE_CODE_ARRAY:
      if (TYPE_LENGTH (type) > 0 && TYPE_LENGTH (target) > 0
	  && (type->bounds ()->high.kind () != PROP_UNDEFINED))
	children = TYPE_LENGTH (type) / TYPE_LENGTH (target);
      else
	/* If we don't know how many elements there are, don't display
	   any.  */
	children = 0;
      break;

    case TYPE_CODE_STRUCT:
    case TYPE_CODE_UNION:
      children = type->num_fields ();
      break;

    case TYPE_CODE_PTR:
      /* The type here is a pointer to non-struct.  Typically, pointers
	 have one child, except for function ptrs, which have no children,
	 and except for void*, as we don't know what to show.

         We can show char* so we allow it to be dereferenced.  If you decide
         to test for it, please mind that a little magic is necessary to
         properly identify it: char* has TYPE_CODE == TYPE_CODE_INT and 
         TYPE_NAME == "char".  */
      if (target->code () == TYPE_CODE_FUNC
	  || target->code () == TYPE_CODE_VOID)
	children = 0;
      else
	children = 1;
      break;

    default:
      /* Other types have no children.  */
      break;
    }

  return children;
}

static std::string
c_name_of_variable (const struct varobj *parent)
{
  return parent->name;
}

/* Return the value of element TYPE_INDEX of a structure
   value VALUE.  VALUE's type should be a structure,
   or union, or a typedef to struct/union.

   Returns NULL if getting the value fails.  Never throws.  */

static struct value *
value_struct_element_index (struct value *value, int type_index)
{
  struct value *result = NULL;
  struct type *type = value_type (value);

  type = check_typedef (type);

  gdb_assert (type->code () == TYPE_CODE_STRUCT
	      || type->code () == TYPE_CODE_UNION);

  try
    {
      if (field_is_static (&type->field (type_index)))
	result = value_static_field (type, type_index);
      else
	result = value_primitive_field (value, 0, type_index, type);
    }
  catch (const gdb_exception_error &e)
    {
      return NULL;
    }

  return result;
}

/* Obtain the information about child INDEX of the variable
   object PARENT.
   If CNAME is not null, sets *CNAME to the name of the child relative
   to the parent.
   If CVALUE is not null, sets *CVALUE to the value of the child.
   If CTYPE is not null, sets *CTYPE to the type of the child.

   If any of CNAME, CVALUE, or CTYPE is not null, but the corresponding
   information cannot be determined, set *CNAME, *CVALUE, or *CTYPE
   to empty.  */

static void 
c_describe_child (const struct varobj *parent, int index,
		  std::string *cname, struct value **cvalue,
		  struct type **ctype, std::string *cfull_expression)
{
  struct value *value = parent->value.get ();
  struct type *type = varobj_get_value_type (parent);
  std::string parent_expression;
  int was_ptr;

  if (cname)
    *cname = std::string ();
  if (cvalue)
    *cvalue = NULL;
  if (ctype)
    *ctype = NULL;
  if (cfull_expression)
    {
      *cfull_expression = std::string ();
      parent_expression
	= varobj_get_path_expr (varobj_get_path_expr_parent (parent));
    }
  adjust_value_for_child_access (&value, &type, &was_ptr, 0);

  switch (type->code ())
    {
    case TYPE_CODE_ARRAY:
      if (cname)
	*cname = int_string (index + type->bounds ()->low.const_val (),
			     10, 1, 0, 0);

      if (cvalue && value)
	{
	  int real_index
	    = index + type->bounds ()->low.const_val ();

	  try
	    {
	      *cvalue = value_subscript (value, real_index);
	    }
	  catch (const gdb_exception_error &except)
	    {
	    }
	}

      if (ctype)
	*ctype = get_target_type (type);

      if (cfull_expression)
	*cfull_expression = string_printf
	  ("(%s)[%s]", parent_expression.c_str (),
	   int_string (index + type->bounds ()->low.const_val (),
		       10, 1, 0, 0));

      break;

    case TYPE_CODE_STRUCT:
    case TYPE_CODE_UNION:
      {
	const char *field_name;

	/* If the type is anonymous and the field has no name,
	   set an appropriate name.  */
	field_name = TYPE_FIELD_NAME (type, index);
	if (field_name == NULL || *field_name == '\0')
	  {
	    if (cname)
	      {
		if (type->field (index).type ()->code ()
		    == TYPE_CODE_STRUCT)
		  *cname = ANONYMOUS_STRUCT_NAME;
		else
		  *cname = ANONYMOUS_UNION_NAME;
	      }

	    if (cfull_expression)
	      *cfull_expression = "";
	  }
	else
	  {
	    if (cname)
	      *cname = field_name;

	    if (cfull_expression)
	      {
		const char *join = was_ptr ? "->" : ".";

		*cfull_expression = string_printf ("(%s)%s%s",
						   parent_expression.c_str (),
						   join, field_name);
	      }
	  }

	if (cvalue && value)
	  {
	    /* For C, varobj index is the same as type index.  */
	    *cvalue = value_struct_element_index (value, index);
	  }

	if (ctype)
	  *ctype = type->field (index).type ();
      }
      break;

    case TYPE_CODE_PTR:
      if (cname)
	*cname = string_printf ("*%s", parent->name.c_str ());

      if (cvalue && value)
	{
	  try
	    {
	      *cvalue = value_ind (value);
	    }

	  catch (const gdb_exception_error &except)
	    {
	      *cvalue = NULL;
	    }
	}

      /* Don't use get_target_type because it calls
	 check_typedef and here, we want to show the true
	 declared type of the variable.  */
      if (ctype)
	*ctype = TYPE_TARGET_TYPE (type);

      if (cfull_expression)
	*cfull_expression = string_printf ("*(%s)", parent_expression.c_str ());
      break;

    default:
      /* This should not happen.  */
      if (cname)
	*cname = "???";
      if (cfull_expression)
	*cfull_expression = "???";
      /* Don't set value and type, we don't know then.  */
    }
}

static std::string
c_name_of_child (const struct varobj *parent, int index)
{
  std::string name;

  c_describe_child (parent, index, &name, NULL, NULL, NULL);
  return name;
}

static std::string
c_path_expr_of_child (const struct varobj *child)
{
  std::string path_expr;

  c_describe_child (child->parent, child->index, NULL, NULL, NULL, 
		    &path_expr);
  return path_expr;
}

static struct value *
c_value_of_child (const struct varobj *parent, int index)
{
  struct value *value = NULL;

  c_describe_child (parent, index, NULL, &value, NULL, NULL);
  return value;
}

static struct type *
c_type_of_child (const struct varobj *parent, int index)
{
  struct type *type = NULL;

  c_describe_child (parent, index, NULL, NULL, &type, NULL);
  return type;
}

/* This returns the type of the variable.  It also skips past typedefs
   to return the real type of the variable.  */

static struct type *
get_type (const struct varobj *var)
{
  struct type *type;

  type = var->type;
  if (type != NULL)
    type = check_typedef (type);

  return type;
}

static std::string
c_value_of_variable (const struct varobj *var,
		     enum varobj_display_formats format)
{
  /* BOGUS: if val_print sees a struct/class, or a reference to one,
     it will print out its children instead of "{...}".  So we need to
     catch that case explicitly.  */
  struct type *type = get_type (var);

  /* Strip top-level references.  */
  while (TYPE_IS_REFERENCE (type))
    type = check_typedef (TYPE_TARGET_TYPE (type));

  switch (type->code ())
    {
    case TYPE_CODE_STRUCT:
    case TYPE_CODE_UNION:
      return "{...}";
      /* break; */

    case TYPE_CODE_ARRAY:
      return string_printf ("[%d]", var->num_children);
      /* break; */

    default:
      {
	if (var->value == NULL)
	  {
	    /* This can happen if we attempt to get the value of a struct
	       member when the parent is an invalid pointer.  This is an
	       error condition, so we should tell the caller.  */
	    return std::string ();
	  }
	else
	  {
	    if (var->not_fetched && value_lazy (var->value.get ()))
	      /* Frozen variable and no value yet.  We don't
		 implicitly fetch the value.  MI response will
		 use empty string for the value, which is OK.  */
	      return std::string ();

	    gdb_assert (varobj_value_is_changeable_p (var));
	    gdb_assert (!value_lazy (var->value.get ()));
	    
	    /* If the specified format is the current one,
	       we can reuse print_value.  */
	    if (format == var->format)
	      return var->print_value;
	    else
	      return varobj_value_get_print_value (var->value.get (), format,
						   var);
	  }
      }
    }
}


/* varobj operations for c.  */

const struct lang_varobj_ops c_varobj_ops =
{
   c_number_of_children,
   c_name_of_variable,
   c_name_of_child,
   c_path_expr_of_child,
   c_value_of_child,
   c_type_of_child,
   c_value_of_variable,
   varobj_default_value_is_changeable_p,
   NULL, /* value_has_mutated */
   c_is_path_expr_parent  /* is_path_expr_parent */
};

/* A little convenience enum for dealing with C++.  */
enum vsections
{
  v_public = 0, v_private, v_protected
};

/* C++ */

static int
cplus_number_of_children (const struct varobj *var)
{
  struct value *value = NULL;
  struct type *type;
  int children, dont_know;
  int lookup_actual_type = 0;
  struct value_print_options opts;

  dont_know = 1;
  children = 0;

  get_user_print_options (&opts);

  if (!CPLUS_FAKE_CHILD (var))
    {
      type = varobj_get_value_type (var);

      /* It is necessary to access a real type (via RTTI).  */
      if (opts.objectprint)
        {
          value = var->value.get ();
          lookup_actual_type = (TYPE_IS_REFERENCE (var->type)
				|| var->type->code () == TYPE_CODE_PTR);
        }
      adjust_value_for_child_access (&value, &type, NULL, lookup_actual_type);

      if (((type->code ()) == TYPE_CODE_STRUCT)
	  || ((type->code ()) == TYPE_CODE_UNION))
	{
	  int kids[3];

	  cplus_class_num_children (type, kids);
	  if (kids[v_public] != 0)
	    children++;
	  if (kids[v_private] != 0)
	    children++;
	  if (kids[v_protected] != 0)
	    children++;

	  /* Add any baseclasses.  */
	  children += TYPE_N_BASECLASSES (type);
	  dont_know = 0;

	  /* FIXME: save children in var.  */
	}
    }
  else
    {
      int kids[3];

      type = varobj_get_value_type (var->parent);

      /* It is necessary to access a real type (via RTTI).  */
      if (opts.objectprint)
        {
	  const struct varobj *parent = var->parent;

	  value = parent->value.get ();
	  lookup_actual_type = (TYPE_IS_REFERENCE (parent->type)
				|| parent->type->code () == TYPE_CODE_PTR);
        }
      adjust_value_for_child_access (&value, &type, NULL, lookup_actual_type);

      cplus_class_num_children (type, kids);
      if (var->name == "public")
	children = kids[v_public];
      else if (var->name == "private")
	children = kids[v_private];
      else
	children = kids[v_protected];
      dont_know = 0;
    }

  if (dont_know)
    children = c_number_of_children (var);

  return children;
}

/* Compute # of public, private, and protected variables in this class.
   That means we need to descend into all baseclasses and find out
   how many are there, too.  */

static void
cplus_class_num_children (struct type *type, int children[3])
{
  int i, vptr_fieldno;
  struct type *basetype = NULL;

  children[v_public] = 0;
  children[v_private] = 0;
  children[v_protected] = 0;

  vptr_fieldno = get_vptr_fieldno (type, &basetype);
  for (i = TYPE_N_BASECLASSES (type); i < type->num_fields (); i++)
    {
      /* If we have a virtual table pointer, omit it.  Even if virtual
	 table pointers are not specifically marked in the debug info,
	 they should be artificial.  */
      if ((type == basetype && i == vptr_fieldno)
	  || TYPE_FIELD_ARTIFICIAL (type, i))
	continue;

      if (TYPE_FIELD_PROTECTED (type, i))
	children[v_protected]++;
      else if (TYPE_FIELD_PRIVATE (type, i))
	children[v_private]++;
      else
	children[v_public]++;
    }
}

static std::string
cplus_name_of_variable (const struct varobj *parent)
{
  return c_name_of_variable (parent);
}

enum accessibility { private_field, protected_field, public_field };

/* Check if field INDEX of TYPE has the specified accessibility.
   Return 0 if so and 1 otherwise.  */

static int 
match_accessibility (struct type *type, int index, enum accessibility acc)
{
  if (acc == private_field && TYPE_FIELD_PRIVATE (type, index))
    return 1;
  else if (acc == protected_field && TYPE_FIELD_PROTECTED (type, index))
    return 1;
  else if (acc == public_field && !TYPE_FIELD_PRIVATE (type, index)
	   && !TYPE_FIELD_PROTECTED (type, index))
    return 1;
  else
    return 0;
}

static void
cplus_describe_child (const struct varobj *parent, int index,
		      std::string *cname, struct value **cvalue, struct type **ctype,
		      std::string *cfull_expression)
{
  struct value *value;
  struct type *type;
  int was_ptr;
  int lookup_actual_type = 0;
  const char *parent_expression = NULL;
  const struct varobj *var;
  struct value_print_options opts;

  if (cname)
    *cname = std::string ();
  if (cvalue)
    *cvalue = NULL;
  if (ctype)
    *ctype = NULL;
  if (cfull_expression)
    *cfull_expression = std::string ();

  get_user_print_options (&opts);

  var = (CPLUS_FAKE_CHILD (parent)) ? parent->parent : parent;
  if (opts.objectprint)
    lookup_actual_type = (TYPE_IS_REFERENCE (var->type)
			  || var->type->code () == TYPE_CODE_PTR);
  value = var->value.get ();
  type = varobj_get_value_type (var);
  if (cfull_expression)
    parent_expression
      = varobj_get_path_expr (varobj_get_path_expr_parent (var));

  adjust_value_for_child_access (&value, &type, &was_ptr, lookup_actual_type);

  if (type->code () == TYPE_CODE_STRUCT
      || type->code () == TYPE_CODE_UNION)
    {
      const char *join = was_ptr ? "->" : ".";

      if (CPLUS_FAKE_CHILD (parent))
	{
	  /* The fields of the class type are ordered as they
	     appear in the class.  We are given an index for a
	     particular access control type ("public","protected",
	     or "private").  We must skip over fields that don't
	     have the access control we are looking for to properly
	     find the indexed field.  */
	  int type_index = TYPE_N_BASECLASSES (type);
	  enum accessibility acc = public_field;
	  int vptr_fieldno;
	  struct type *basetype = NULL;
	  const char *field_name;

	  vptr_fieldno = get_vptr_fieldno (type, &basetype);
	  if (parent->name == "private")
	    acc = private_field;
	  else if (parent->name == "protected")
	    acc = protected_field;

	  while (index >= 0)
	    {
	      if ((type == basetype && type_index == vptr_fieldno)
		  || TYPE_FIELD_ARTIFICIAL (type, type_index))
		; /* ignore vptr */
	      else if (match_accessibility (type, type_index, acc))
		    --index;
		  ++type_index;
	    }
	  --type_index;

	  /* If the type is anonymous and the field has no name,
	     set an appropriate name.  */
	  field_name = TYPE_FIELD_NAME (type, type_index);
	  if (field_name == NULL || *field_name == '\0')
	    {
	      if (cname)
		{
		  if (type->field (type_index).type ()->code ()
		      == TYPE_CODE_STRUCT)
		    *cname = ANONYMOUS_STRUCT_NAME;
		  else if (type->field (type_index).type ()->code ()
			   == TYPE_CODE_UNION)
		    *cname = ANONYMOUS_UNION_NAME;
		}

	      if (cfull_expression)
		*cfull_expression = std::string ();
	    }
	  else
	    {
	      if (cname)
		*cname = TYPE_FIELD_NAME (type, type_index);

	      if (cfull_expression)
		*cfull_expression
		  = string_printf ("((%s)%s%s)", parent_expression, join,
				   field_name);
	    }

	  if (cvalue && value)
	    *cvalue = value_struct_element_index (value, type_index);

	  if (ctype)
	    *ctype = type->field (type_index).type ();
	}
      else if (index < TYPE_N_BASECLASSES (type))
	{
	  /* This is a baseclass.  */
	  if (cname)
	    *cname = TYPE_FIELD_NAME (type, index);

	  if (cvalue && value)
	    *cvalue = value_cast (type->field (index).type (), value);

	  if (ctype)
	    {
	      *ctype = type->field (index).type ();
	    }

	  if (cfull_expression)
	    {
	      const char *ptr = was_ptr ? "*" : "";

	      /* Cast the parent to the base' type.  Note that in gdb,
		 expression like 
		         (Base1)d
		 will create an lvalue, for all appearences, so we don't
		 need to use more fancy:
		         *(Base1*)(&d)
		 construct.

		 When we are in the scope of the base class or of one
		 of its children, the type field name will be interpreted
		 as a constructor, if it exists.  Therefore, we must
		 indicate that the name is a class name by using the
		 'class' keyword.  See PR mi/11912  */
	      *cfull_expression = string_printf ("(%s(class %s%s) %s)",
						 ptr,
						 TYPE_FIELD_NAME (type, index),
						 ptr,
						 parent_expression);
	    }
	}
      else
	{
	  const char *access = NULL;
	  int children[3];

	  cplus_class_num_children (type, children);

	  /* Everything beyond the baseclasses can
	     only be "public", "private", or "protected"

	     The special "fake" children are always output by varobj in
	     this order.  So if INDEX == 2, it MUST be "protected".  */
	  index -= TYPE_N_BASECLASSES (type);
	  switch (index)
	    {
	    case 0:
	      if (children[v_public] > 0)
	 	access = "public";
	      else if (children[v_private] > 0)
	 	access = "private";
	      else 
	 	access = "protected";
	      break;
	    case 1:
	      if (children[v_public] > 0)
		{
		  if (children[v_private] > 0)
		    access = "private";
		  else
		    access = "protected";
		}
	      else if (children[v_private] > 0)
	 	access = "protected";
	      break;
	    case 2:
	      /* Must be protected.  */
	      access = "protected";
	      break;
	    default:
	      /* error!  */
	      break;
	    }

	  gdb_assert (access);
	  if (cname)
	    *cname = access;

	  /* Value and type and full expression are null here.  */
	}
    }
  else
    {
      c_describe_child (parent, index, cname, cvalue, ctype, cfull_expression);
    }  
}

static std::string
cplus_name_of_child (const struct varobj *parent, int index)
{
  std::string name;

  cplus_describe_child (parent, index, &name, NULL, NULL, NULL);
  return name;
}

static std::string
cplus_path_expr_of_child (const struct varobj *child)
{
  std::string path_expr;

  cplus_describe_child (child->parent, child->index, NULL, NULL, NULL, 
			&path_expr);
  return path_expr;
}

static struct value *
cplus_value_of_child (const struct varobj *parent, int index)
{
  struct value *value = NULL;

  cplus_describe_child (parent, index, NULL, &value, NULL, NULL);
  return value;
}

static struct type *
cplus_type_of_child (const struct varobj *parent, int index)
{
  struct type *type = NULL;

  cplus_describe_child (parent, index, NULL, NULL, &type, NULL);
  return type;
}

static std::string
cplus_value_of_variable (const struct varobj *var,
			 enum varobj_display_formats format)
{

  /* If we have one of our special types, don't print out
     any value.  */
  if (CPLUS_FAKE_CHILD (var))
    return std::string ();

  return c_value_of_variable (var, format);
}


/* varobj operations for c++.  */

const struct lang_varobj_ops cplus_varobj_ops =
{
   cplus_number_of_children,
   cplus_name_of_variable,
   cplus_name_of_child,
   cplus_path_expr_of_child,
   cplus_value_of_child,
   cplus_type_of_child,
   cplus_value_of_variable,
   varobj_default_value_is_changeable_p,
   NULL, /* value_has_mutated */
   c_is_path_expr_parent  /* is_path_expr_parent */
};