1 /* Implementation of the GDB variable objects API.
3 Copyright (C) 1999-2017 Free Software Foundation, Inc.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "expression.h"
26 #include "gdb_regex.h"
30 #include "gdbthread.h"
32 #include "varobj-iter.h"
35 #include "python/python.h"
36 #include "python/python-internal.h"
37 #include "python/py-ref.h"
42 /* Non-zero if we want to see trace of varobj level stuff. */
44 unsigned int varobjdebug = 0;
46 show_varobjdebug (struct ui_file *file, int from_tty,
47 struct cmd_list_element *c, const char *value)
49 fprintf_filtered (file, _("Varobj debugging is %s.\n"), value);
52 /* String representations of gdb's format codes. */
53 const char *varobj_format_string[] =
54 { "natural", "binary", "decimal", "hexadecimal", "octal", "zero-hexadecimal" };
56 /* True if we want to allow Python-based pretty-printing. */
57 static bool pretty_printing = false;
60 varobj_enable_pretty_printing (void)
62 pretty_printing = true;
67 /* Every root variable has one of these structures saved in its
71 /* The expression for this parent. */
74 /* Block for which this expression is valid. */
75 const struct block *valid_block = NULL;
77 /* The frame for this expression. This field is set iff valid_block is
79 struct frame_id frame = null_frame_id;
81 /* The global thread ID that this varobj_root belongs to. This field
82 is only valid if valid_block is not NULL.
83 When not 0, indicates which thread 'frame' belongs to.
84 When 0, indicates that the thread list was empty when the varobj_root
88 /* If true, the -var-update always recomputes the value in the
89 current thread and frame. Otherwise, variable object is
90 always updated in the specific scope/thread/frame. */
91 bool floating = false;
93 /* Flag that indicates validity: set to false when this varobj_root refers
94 to symbols that do not exist anymore. */
97 /* Language-related operations for this variable and its
99 const struct lang_varobj_ops *lang_ops = NULL;
101 /* The varobj for this root node. */
102 struct varobj *rootvar = NULL;
104 /* Next root variable */
105 struct varobj_root *next = NULL;
108 /* Dynamic part of varobj. */
110 struct varobj_dynamic
112 /* Whether the children of this varobj were requested. This field is
113 used to decide if dynamic varobj should recompute their children.
114 In the event that the frontend never asked for the children, we
116 bool children_requested = false;
118 /* The pretty-printer constructor. If NULL, then the default
119 pretty-printer will be looked up. If None, then no
120 pretty-printer will be installed. */
121 PyObject *constructor = NULL;
123 /* The pretty-printer that has been constructed. If NULL, then a
124 new printer object is needed, and one will be constructed. */
125 PyObject *pretty_printer = NULL;
127 /* The iterator returned by the printer's 'children' method, or NULL
129 struct varobj_iter *child_iter = NULL;
131 /* We request one extra item from the iterator, so that we can
132 report to the caller whether there are more items than we have
133 already reported. However, we don't want to install this value
134 when we read it, because that will mess up future updates. So,
135 we stash it here instead. */
136 varobj_item *saved_item = NULL;
139 /* A list of varobjs */
147 /* Private function prototypes */
149 /* Helper functions for the above subcommands. */
151 static int delete_variable (struct varobj *, bool);
153 static void delete_variable_1 (int *, struct varobj *, bool, bool);
155 static bool install_variable (struct varobj *);
157 static void uninstall_variable (struct varobj *);
159 static struct varobj *create_child (struct varobj *, int, std::string &);
161 static struct varobj *
162 create_child_with_value (struct varobj *parent, int index,
163 struct varobj_item *item);
165 /* Utility routines */
167 static enum varobj_display_formats variable_default_display (struct varobj *);
169 static bool update_type_if_necessary (struct varobj *var,
170 struct value *new_value);
172 static bool install_new_value (struct varobj *var, struct value *value,
175 /* Language-specific routines. */
177 static int number_of_children (const struct varobj *);
179 static std::string name_of_variable (const struct varobj *);
181 static std::string name_of_child (struct varobj *, int);
183 static struct value *value_of_root (struct varobj **var_handle, bool *);
185 static struct value *value_of_child (const struct varobj *parent, int index);
187 static std::string my_value_of_variable (struct varobj *var,
188 enum varobj_display_formats format);
190 static bool is_root_p (const struct varobj *var);
192 static struct varobj *varobj_add_child (struct varobj *var,
193 struct varobj_item *item);
197 /* Mappings of varobj_display_formats enums to gdb's format codes. */
198 static int format_code[] = { 0, 't', 'd', 'x', 'o', 'z' };
200 /* Header of the list of root variable objects. */
201 static struct varobj_root *rootlist;
203 /* Prime number indicating the number of buckets in the hash table. */
204 /* A prime large enough to avoid too many collisions. */
205 #define VAROBJ_TABLE_SIZE 227
207 /* Pointer to the varobj hash table (built at run time). */
208 static struct vlist **varobj_table;
212 /* API Implementation */
214 is_root_p (const struct varobj *var)
216 return (var->root->rootvar == var);
221 /* See python-internal.h. */
222 gdbpy_enter_varobj::gdbpy_enter_varobj (const struct varobj *var)
223 : gdbpy_enter (var->root->exp->gdbarch, var->root->exp->language_defn)
229 /* Return the full FRAME which corresponds to the given CORE_ADDR
230 or NULL if no FRAME on the chain corresponds to CORE_ADDR. */
232 static struct frame_info *
233 find_frame_addr_in_frame_chain (CORE_ADDR frame_addr)
235 struct frame_info *frame = NULL;
237 if (frame_addr == (CORE_ADDR) 0)
240 for (frame = get_current_frame ();
242 frame = get_prev_frame (frame))
244 /* The CORE_ADDR we get as argument was parsed from a string GDB
245 output as $fp. This output got truncated to gdbarch_addr_bit.
246 Truncate the frame base address in the same manner before
247 comparing it against our argument. */
248 CORE_ADDR frame_base = get_frame_base_address (frame);
249 int addr_bit = gdbarch_addr_bit (get_frame_arch (frame));
251 if (addr_bit < (sizeof (CORE_ADDR) * HOST_CHAR_BIT))
252 frame_base &= ((CORE_ADDR) 1 << addr_bit) - 1;
254 if (frame_base == frame_addr)
261 /* Creates a varobj (not its children). */
264 varobj_create (const char *objname,
265 const char *expression, CORE_ADDR frame, enum varobj_type type)
267 /* Fill out a varobj structure for the (root) variable being constructed. */
268 std::unique_ptr<varobj> var (new varobj (new varobj_root));
270 if (expression != NULL)
272 struct frame_info *fi;
273 struct frame_id old_id = null_frame_id;
274 const struct block *block;
276 struct value *value = NULL;
279 /* Parse and evaluate the expression, filling in as much of the
280 variable's data as possible. */
282 if (has_stack_frames ())
284 /* Allow creator to specify context of variable. */
285 if ((type == USE_CURRENT_FRAME) || (type == USE_SELECTED_FRAME))
286 fi = get_selected_frame (NULL);
288 /* FIXME: cagney/2002-11-23: This code should be doing a
289 lookup using the frame ID and not just the frame's
290 ``address''. This, of course, means an interface
291 change. However, with out that interface change ISAs,
292 such as the ia64 with its two stacks, won't work.
293 Similar goes for the case where there is a frameless
295 fi = find_frame_addr_in_frame_chain (frame);
300 /* frame = -2 means always use selected frame. */
301 if (type == USE_SELECTED_FRAME)
302 var->root->floating = true;
308 block = get_frame_block (fi, 0);
309 pc = get_frame_pc (fi);
313 innermost_block = NULL;
314 /* Wrap the call to parse expression, so we can
315 return a sensible error. */
318 var->root->exp = parse_exp_1 (&p, pc, block, 0);
321 CATCH (except, RETURN_MASK_ERROR)
327 /* Don't allow variables to be created for types. */
328 if (var->root->exp->elts[0].opcode == OP_TYPE
329 || var->root->exp->elts[0].opcode == OP_TYPEOF
330 || var->root->exp->elts[0].opcode == OP_DECLTYPE)
332 fprintf_unfiltered (gdb_stderr, "Attempt to use a type name"
333 " as an expression.\n");
337 var->format = variable_default_display (var.get ());
338 var->root->valid_block = innermost_block;
339 var->name = expression;
340 /* For a root var, the name and the expr are the same. */
341 var->path_expr = expression;
343 /* When the frame is different from the current frame,
344 we must select the appropriate frame before parsing
345 the expression, otherwise the value will not be current.
346 Since select_frame is so benign, just call it for all cases. */
349 /* User could specify explicit FRAME-ADDR which was not found but
350 EXPRESSION is frame specific and we would not be able to evaluate
351 it correctly next time. With VALID_BLOCK set we must also set
352 FRAME and THREAD_ID. */
354 error (_("Failed to find the specified frame"));
356 var->root->frame = get_frame_id (fi);
357 var->root->thread_id = ptid_to_global_thread_id (inferior_ptid);
358 old_id = get_frame_id (get_selected_frame (NULL));
362 /* We definitely need to catch errors here.
363 If evaluate_expression succeeds we got the value we wanted.
364 But if it fails, we still go on with a call to evaluate_type(). */
367 value = evaluate_expression (var->root->exp.get ());
369 CATCH (except, RETURN_MASK_ERROR)
371 /* Error getting the value. Try to at least get the
373 struct value *type_only_value = evaluate_type (var->root->exp.get ());
375 var->type = value_type (type_only_value);
381 int real_type_found = 0;
383 var->type = value_actual_type (value, 0, &real_type_found);
385 value = value_cast (var->type, value);
388 /* Set language info */
389 var->root->lang_ops = var->root->exp->language_defn->la_varobj_ops;
391 install_new_value (var.get (), value, 1 /* Initial assignment */);
393 /* Set ourselves as our root. */
394 var->root->rootvar = var.get ();
396 /* Reset the selected frame. */
397 if (frame_id_p (old_id))
398 select_frame (frame_find_by_id (old_id));
401 /* If the variable object name is null, that means this
402 is a temporary variable, so don't install it. */
404 if ((var != NULL) && (objname != NULL))
406 var->obj_name = objname;
408 /* If a varobj name is duplicated, the install will fail so
410 if (!install_variable (var.get ()))
414 return var.release ();
417 /* Generates an unique name that can be used for a varobj. */
420 varobj_gen_name (void)
424 /* Generate a name for this object. */
426 return string_printf ("var%d", id);
429 /* Given an OBJNAME, returns the pointer to the corresponding varobj. Call
430 error if OBJNAME cannot be found. */
433 varobj_get_handle (const char *objname)
437 unsigned int index = 0;
440 for (chp = objname; *chp; chp++)
442 index = (index + (i++ * (unsigned int) *chp)) % VAROBJ_TABLE_SIZE;
445 cv = *(varobj_table + index);
446 while (cv != NULL && cv->var->obj_name != objname)
450 error (_("Variable object not found"));
455 /* Given the handle, return the name of the object. */
458 varobj_get_objname (const struct varobj *var)
460 return var->obj_name.c_str ();
463 /* Given the handle, return the expression represented by the
467 varobj_get_expression (const struct varobj *var)
469 return name_of_variable (var);
475 varobj_delete (struct varobj *var, bool only_children)
477 return delete_variable (var, only_children);
482 /* Convenience function for varobj_set_visualizer. Instantiate a
483 pretty-printer for a given value. */
485 instantiate_pretty_printer (PyObject *constructor, struct value *value)
487 PyObject *val_obj = NULL;
490 val_obj = value_to_value_object (value);
494 printer = PyObject_CallFunctionObjArgs (constructor, val_obj, NULL);
501 /* Set/Get variable object display format. */
503 enum varobj_display_formats
504 varobj_set_display_format (struct varobj *var,
505 enum varobj_display_formats format)
512 case FORMAT_HEXADECIMAL:
514 case FORMAT_ZHEXADECIMAL:
515 var->format = format;
519 var->format = variable_default_display (var);
522 if (varobj_value_is_changeable_p (var)
523 && var->value && !value_lazy (var->value))
525 var->print_value = varobj_value_get_print_value (var->value,
532 enum varobj_display_formats
533 varobj_get_display_format (const struct varobj *var)
538 gdb::unique_xmalloc_ptr<char>
539 varobj_get_display_hint (const struct varobj *var)
541 gdb::unique_xmalloc_ptr<char> result;
544 if (!gdb_python_initialized)
547 gdbpy_enter_varobj enter_py (var);
549 if (var->dynamic->pretty_printer != NULL)
550 result = gdbpy_get_display_hint (var->dynamic->pretty_printer);
556 /* Return true if the varobj has items after TO, false otherwise. */
559 varobj_has_more (const struct varobj *var, int to)
561 if (var->children.size () > to)
564 return ((to == -1 || var->children.size () == to)
565 && (var->dynamic->saved_item != NULL));
568 /* If the variable object is bound to a specific thread, that
569 is its evaluation can always be done in context of a frame
570 inside that thread, returns GDB id of the thread -- which
571 is always positive. Otherwise, returns -1. */
573 varobj_get_thread_id (const struct varobj *var)
575 if (var->root->valid_block && var->root->thread_id > 0)
576 return var->root->thread_id;
582 varobj_set_frozen (struct varobj *var, bool frozen)
584 /* When a variable is unfrozen, we don't fetch its value.
585 The 'not_fetched' flag remains set, so next -var-update
588 We don't fetch the value, because for structures the client
589 should do -var-update anyway. It would be bad to have different
590 client-size logic for structure and other types. */
591 var->frozen = frozen;
595 varobj_get_frozen (const struct varobj *var)
600 /* A helper function that restricts a range to what is actually
601 available in a VEC. This follows the usual rules for the meaning
602 of FROM and TO -- if either is negative, the entire range is
606 varobj_restrict_range (const std::vector<varobj *> &children,
609 int len = children.size ();
611 if (*from < 0 || *to < 0)
627 /* A helper for update_dynamic_varobj_children that installs a new
628 child when needed. */
631 install_dynamic_child (struct varobj *var,
632 std::vector<varobj *> *changed,
633 std::vector<varobj *> *type_changed,
634 std::vector<varobj *> *newobj,
635 std::vector<varobj *> *unchanged,
638 struct varobj_item *item)
640 if (var->children.size () < index + 1)
642 /* There's no child yet. */
643 struct varobj *child = varobj_add_child (var, item);
647 newobj->push_back (child);
653 varobj *existing = var->children[index];
654 bool type_updated = update_type_if_necessary (existing, item->value);
658 if (type_changed != NULL)
659 type_changed->push_back (existing);
661 if (install_new_value (existing, item->value, 0))
663 if (!type_updated && changed != NULL)
664 changed->push_back (existing);
666 else if (!type_updated && unchanged != NULL)
667 unchanged->push_back (existing);
674 dynamic_varobj_has_child_method (const struct varobj *var)
676 PyObject *printer = var->dynamic->pretty_printer;
678 if (!gdb_python_initialized)
681 gdbpy_enter_varobj enter_py (var);
682 return PyObject_HasAttr (printer, gdbpy_children_cst);
686 /* A factory for creating dynamic varobj's iterators. Returns an
687 iterator object suitable for iterating over VAR's children. */
689 static struct varobj_iter *
690 varobj_get_iterator (struct varobj *var)
693 if (var->dynamic->pretty_printer)
694 return py_varobj_get_iterator (var, var->dynamic->pretty_printer);
697 gdb_assert_not_reached (_("\
698 requested an iterator from a non-dynamic varobj"));
701 /* Release and clear VAR's saved item, if any. */
704 varobj_clear_saved_item (struct varobj_dynamic *var)
706 if (var->saved_item != NULL)
708 value_free (var->saved_item->value);
709 delete var->saved_item;
710 var->saved_item = NULL;
715 update_dynamic_varobj_children (struct varobj *var,
716 std::vector<varobj *> *changed,
717 std::vector<varobj *> *type_changed,
718 std::vector<varobj *> *newobj,
719 std::vector<varobj *> *unchanged,
721 bool update_children,
729 if (update_children || var->dynamic->child_iter == NULL)
731 varobj_iter_delete (var->dynamic->child_iter);
732 var->dynamic->child_iter = varobj_get_iterator (var);
734 varobj_clear_saved_item (var->dynamic);
738 if (var->dynamic->child_iter == NULL)
742 i = var->children.size ();
744 /* We ask for one extra child, so that MI can report whether there
745 are more children. */
746 for (; to < 0 || i < to + 1; ++i)
750 /* See if there was a leftover from last time. */
751 if (var->dynamic->saved_item != NULL)
753 item = var->dynamic->saved_item;
754 var->dynamic->saved_item = NULL;
758 item = varobj_iter_next (var->dynamic->child_iter);
759 /* Release vitem->value so its lifetime is not bound to the
760 execution of a command. */
761 if (item != NULL && item->value != NULL)
762 release_value_or_incref (item->value);
767 /* Iteration is done. Remove iterator from VAR. */
768 varobj_iter_delete (var->dynamic->child_iter);
769 var->dynamic->child_iter = NULL;
772 /* We don't want to push the extra child on any report list. */
773 if (to < 0 || i < to)
775 bool can_mention = from < 0 || i >= from;
777 install_dynamic_child (var, can_mention ? changed : NULL,
778 can_mention ? type_changed : NULL,
779 can_mention ? newobj : NULL,
780 can_mention ? unchanged : NULL,
781 can_mention ? cchanged : NULL, i,
788 var->dynamic->saved_item = item;
790 /* We want to truncate the child list just before this
796 if (i < var->children.size ())
799 for (int j = i; j < var->children.size (); ++j)
800 varobj_delete (var->children[j], 0);
802 var->children.resize (i);
805 /* If there are fewer children than requested, note that the list of
807 if (to >= 0 && var->children.size () < to)
810 var->num_children = var->children.size ();
816 varobj_get_num_children (struct varobj *var)
818 if (var->num_children == -1)
820 if (varobj_is_dynamic_p (var))
824 /* If we have a dynamic varobj, don't report -1 children.
825 So, try to fetch some children first. */
826 update_dynamic_varobj_children (var, NULL, NULL, NULL, NULL, &dummy,
830 var->num_children = number_of_children (var);
833 return var->num_children >= 0 ? var->num_children : 0;
836 /* Creates a list of the immediate children of a variable object;
837 the return code is the number of such children or -1 on error. */
839 const std::vector<varobj *> &
840 varobj_list_children (struct varobj *var, int *from, int *to)
842 var->dynamic->children_requested = true;
844 if (varobj_is_dynamic_p (var))
846 bool children_changed;
848 /* This, in theory, can result in the number of children changing without
849 frontend noticing. But well, calling -var-list-children on the same
850 varobj twice is not something a sane frontend would do. */
851 update_dynamic_varobj_children (var, NULL, NULL, NULL, NULL,
852 &children_changed, false, 0, *to);
853 varobj_restrict_range (var->children, from, to);
854 return var->children;
857 if (var->num_children == -1)
858 var->num_children = number_of_children (var);
860 /* If that failed, give up. */
861 if (var->num_children == -1)
862 return var->children;
864 /* If we're called when the list of children is not yet initialized,
865 allocate enough elements in it. */
866 while (var->children.size () < var->num_children)
867 var->children.push_back (NULL);
869 for (int i = 0; i < var->num_children; i++)
871 if (var->children[i] == NULL)
873 /* Either it's the first call to varobj_list_children for
874 this variable object, and the child was never created,
875 or it was explicitly deleted by the client. */
876 std::string name = name_of_child (var, i);
877 var->children[i] = create_child (var, i, name);
881 varobj_restrict_range (var->children, from, to);
882 return var->children;
885 static struct varobj *
886 varobj_add_child (struct varobj *var, struct varobj_item *item)
888 varobj *v = create_child_with_value (var, var->children.size (), item);
890 var->children.push_back (v);
895 /* Obtain the type of an object Variable as a string similar to the one gdb
896 prints on the console. The caller is responsible for freeing the string.
900 varobj_get_type (struct varobj *var)
902 /* For the "fake" variables, do not return a type. (Its type is
904 Do not return a type for invalid variables as well. */
905 if (CPLUS_FAKE_CHILD (var) || !var->root->is_valid)
906 return std::string ();
908 return type_to_string (var->type);
911 /* Obtain the type of an object variable. */
914 varobj_get_gdb_type (const struct varobj *var)
919 /* Is VAR a path expression parent, i.e., can it be used to construct
920 a valid path expression? */
923 is_path_expr_parent (const struct varobj *var)
925 gdb_assert (var->root->lang_ops->is_path_expr_parent != NULL);
926 return var->root->lang_ops->is_path_expr_parent (var);
929 /* Is VAR a path expression parent, i.e., can it be used to construct
930 a valid path expression? By default we assume any VAR can be a path
934 varobj_default_is_path_expr_parent (const struct varobj *var)
939 /* Return the path expression parent for VAR. */
941 const struct varobj *
942 varobj_get_path_expr_parent (const struct varobj *var)
944 const struct varobj *parent = var;
946 while (!is_root_p (parent) && !is_path_expr_parent (parent))
947 parent = parent->parent;
952 /* Return a pointer to the full rooted expression of varobj VAR.
953 If it has not been computed yet, compute it. */
956 varobj_get_path_expr (const struct varobj *var)
958 if (var->path_expr.empty ())
960 /* For root varobjs, we initialize path_expr
961 when creating varobj, so here it should be
963 struct varobj *mutable_var = (struct varobj *) var;
964 gdb_assert (!is_root_p (var));
966 mutable_var->path_expr = (*var->root->lang_ops->path_expr_of_child) (var);
969 return var->path_expr.c_str ();
972 const struct language_defn *
973 varobj_get_language (const struct varobj *var)
975 return var->root->exp->language_defn;
979 varobj_get_attributes (const struct varobj *var)
983 if (varobj_editable_p (var))
984 /* FIXME: define masks for attributes. */
985 attributes |= 0x00000001; /* Editable */
990 /* Return true if VAR is a dynamic varobj. */
993 varobj_is_dynamic_p (const struct varobj *var)
995 return var->dynamic->pretty_printer != NULL;
999 varobj_get_formatted_value (struct varobj *var,
1000 enum varobj_display_formats format)
1002 return my_value_of_variable (var, format);
1006 varobj_get_value (struct varobj *var)
1008 return my_value_of_variable (var, var->format);
1011 /* Set the value of an object variable (if it is editable) to the
1012 value of the given expression. */
1013 /* Note: Invokes functions that can call error(). */
1016 varobj_set_value (struct varobj *var, const char *expression)
1018 struct value *val = NULL; /* Initialize to keep gcc happy. */
1019 /* The argument "expression" contains the variable's new value.
1020 We need to first construct a legal expression for this -- ugh! */
1021 /* Does this cover all the bases? */
1022 struct value *value = NULL; /* Initialize to keep gcc happy. */
1023 int saved_input_radix = input_radix;
1024 const char *s = expression;
1026 gdb_assert (varobj_editable_p (var));
1028 input_radix = 10; /* ALWAYS reset to decimal temporarily. */
1029 expression_up exp = parse_exp_1 (&s, 0, 0, 0);
1032 value = evaluate_expression (exp.get ());
1035 CATCH (except, RETURN_MASK_ERROR)
1037 /* We cannot proceed without a valid expression. */
1042 /* All types that are editable must also be changeable. */
1043 gdb_assert (varobj_value_is_changeable_p (var));
1045 /* The value of a changeable variable object must not be lazy. */
1046 gdb_assert (!value_lazy (var->value));
1048 /* Need to coerce the input. We want to check if the
1049 value of the variable object will be different
1050 after assignment, and the first thing value_assign
1051 does is coerce the input.
1052 For example, if we are assigning an array to a pointer variable we
1053 should compare the pointer with the array's address, not with the
1055 value = coerce_array (value);
1057 /* The new value may be lazy. value_assign, or
1058 rather value_contents, will take care of this. */
1061 val = value_assign (var->value, value);
1064 CATCH (except, RETURN_MASK_ERROR)
1070 /* If the value has changed, record it, so that next -var-update can
1071 report this change. If a variable had a value of '1', we've set it
1072 to '333' and then set again to '1', when -var-update will report this
1073 variable as changed -- because the first assignment has set the
1074 'updated' flag. There's no need to optimize that, because return value
1075 of -var-update should be considered an approximation. */
1076 var->updated = install_new_value (var, val, false /* Compare values. */);
1077 input_radix = saved_input_radix;
1083 /* A helper function to install a constructor function and visualizer
1084 in a varobj_dynamic. */
1087 install_visualizer (struct varobj_dynamic *var, PyObject *constructor,
1088 PyObject *visualizer)
1090 Py_XDECREF (var->constructor);
1091 var->constructor = constructor;
1093 Py_XDECREF (var->pretty_printer);
1094 var->pretty_printer = visualizer;
1096 varobj_iter_delete (var->child_iter);
1097 var->child_iter = NULL;
1100 /* Install the default visualizer for VAR. */
1103 install_default_visualizer (struct varobj *var)
1105 /* Do not install a visualizer on a CPLUS_FAKE_CHILD. */
1106 if (CPLUS_FAKE_CHILD (var))
1109 if (pretty_printing)
1111 PyObject *pretty_printer = NULL;
1115 pretty_printer = gdbpy_get_varobj_pretty_printer (var->value);
1116 if (! pretty_printer)
1118 gdbpy_print_stack ();
1119 error (_("Cannot instantiate printer for default visualizer"));
1123 if (pretty_printer == Py_None)
1125 Py_DECREF (pretty_printer);
1126 pretty_printer = NULL;
1129 install_visualizer (var->dynamic, NULL, pretty_printer);
1133 /* Instantiate and install a visualizer for VAR using CONSTRUCTOR to
1134 make a new object. */
1137 construct_visualizer (struct varobj *var, PyObject *constructor)
1139 PyObject *pretty_printer;
1141 /* Do not install a visualizer on a CPLUS_FAKE_CHILD. */
1142 if (CPLUS_FAKE_CHILD (var))
1145 Py_INCREF (constructor);
1146 if (constructor == Py_None)
1147 pretty_printer = NULL;
1150 pretty_printer = instantiate_pretty_printer (constructor, var->value);
1151 if (! pretty_printer)
1153 gdbpy_print_stack ();
1154 Py_DECREF (constructor);
1155 constructor = Py_None;
1156 Py_INCREF (constructor);
1159 if (pretty_printer == Py_None)
1161 Py_DECREF (pretty_printer);
1162 pretty_printer = NULL;
1166 install_visualizer (var->dynamic, constructor, pretty_printer);
1169 #endif /* HAVE_PYTHON */
1171 /* A helper function for install_new_value. This creates and installs
1172 a visualizer for VAR, if appropriate. */
1175 install_new_value_visualizer (struct varobj *var)
1178 /* If the constructor is None, then we want the raw value. If VAR
1179 does not have a value, just skip this. */
1180 if (!gdb_python_initialized)
1183 if (var->dynamic->constructor != Py_None && var->value != NULL)
1185 gdbpy_enter_varobj enter_py (var);
1187 if (var->dynamic->constructor == NULL)
1188 install_default_visualizer (var);
1190 construct_visualizer (var, var->dynamic->constructor);
1197 /* When using RTTI to determine variable type it may be changed in runtime when
1198 the variable value is changed. This function checks whether type of varobj
1199 VAR will change when a new value NEW_VALUE is assigned and if it is so
1200 updates the type of VAR. */
1203 update_type_if_necessary (struct varobj *var, struct value *new_value)
1207 struct value_print_options opts;
1209 get_user_print_options (&opts);
1210 if (opts.objectprint)
1212 struct type *new_type = value_actual_type (new_value, 0, 0);
1213 std::string new_type_str = type_to_string (new_type);
1214 std::string curr_type_str = varobj_get_type (var);
1216 /* Did the type name change? */
1217 if (curr_type_str != new_type_str)
1219 var->type = new_type;
1221 /* This information may be not valid for a new type. */
1222 varobj_delete (var, 1);
1223 var->children.clear ();
1224 var->num_children = -1;
1233 /* Assign a new value to a variable object. If INITIAL is true,
1234 this is the first assignment after the variable object was just
1235 created, or changed type. In that case, just assign the value
1237 Otherwise, assign the new value, and return true if the value is
1238 different from the current one, false otherwise. The comparison is
1239 done on textual representation of value. Therefore, some types
1240 need not be compared. E.g. for structures the reported value is
1241 always "{...}", so no comparison is necessary here. If the old
1242 value was NULL and new one is not, or vice versa, we always return true.
1244 The VALUE parameter should not be released -- the function will
1245 take care of releasing it when needed. */
1247 install_new_value (struct varobj *var, struct value *value, bool initial)
1251 bool changed = false;
1252 bool intentionally_not_fetched = false;
1254 /* We need to know the varobj's type to decide if the value should
1255 be fetched or not. C++ fake children (public/protected/private)
1256 don't have a type. */
1257 gdb_assert (var->type || CPLUS_FAKE_CHILD (var));
1258 changeable = varobj_value_is_changeable_p (var);
1260 /* If the type has custom visualizer, we consider it to be always
1261 changeable. FIXME: need to make sure this behaviour will not
1262 mess up read-sensitive values. */
1263 if (var->dynamic->pretty_printer != NULL)
1266 need_to_fetch = changeable;
1268 /* We are not interested in the address of references, and given
1269 that in C++ a reference is not rebindable, it cannot
1270 meaningfully change. So, get hold of the real value. */
1272 value = coerce_ref (value);
1274 if (var->type && TYPE_CODE (var->type) == TYPE_CODE_UNION)
1275 /* For unions, we need to fetch the value implicitly because
1276 of implementation of union member fetch. When gdb
1277 creates a value for a field and the value of the enclosing
1278 structure is not lazy, it immediately copies the necessary
1279 bytes from the enclosing values. If the enclosing value is
1280 lazy, the call to value_fetch_lazy on the field will read
1281 the data from memory. For unions, that means we'll read the
1282 same memory more than once, which is not desirable. So
1284 need_to_fetch = true;
1286 /* The new value might be lazy. If the type is changeable,
1287 that is we'll be comparing values of this type, fetch the
1288 value now. Otherwise, on the next update the old value
1289 will be lazy, which means we've lost that old value. */
1290 if (need_to_fetch && value && value_lazy (value))
1292 const struct varobj *parent = var->parent;
1293 bool frozen = var->frozen;
1295 for (; !frozen && parent; parent = parent->parent)
1296 frozen |= parent->frozen;
1298 if (frozen && initial)
1300 /* For variables that are frozen, or are children of frozen
1301 variables, we don't do fetch on initial assignment.
1302 For non-initial assignemnt we do the fetch, since it means we're
1303 explicitly asked to compare the new value with the old one. */
1304 intentionally_not_fetched = true;
1311 value_fetch_lazy (value);
1314 CATCH (except, RETURN_MASK_ERROR)
1316 /* Set the value to NULL, so that for the next -var-update,
1317 we don't try to compare the new value with this value,
1318 that we couldn't even read. */
1325 /* Get a reference now, before possibly passing it to any Python
1326 code that might release it. */
1328 value_incref (value);
1330 /* Below, we'll be comparing string rendering of old and new
1331 values. Don't get string rendering if the value is
1332 lazy -- if it is, the code above has decided that the value
1333 should not be fetched. */
1334 std::string print_value;
1335 if (value != NULL && !value_lazy (value)
1336 && var->dynamic->pretty_printer == NULL)
1337 print_value = varobj_value_get_print_value (value, var->format, var);
1339 /* If the type is changeable, compare the old and the new values.
1340 If this is the initial assignment, we don't have any old value
1342 if (!initial && changeable)
1344 /* If the value of the varobj was changed by -var-set-value,
1345 then the value in the varobj and in the target is the same.
1346 However, that value is different from the value that the
1347 varobj had after the previous -var-update. So need to the
1348 varobj as changed. */
1351 else if (var->dynamic->pretty_printer == NULL)
1353 /* Try to compare the values. That requires that both
1354 values are non-lazy. */
1355 if (var->not_fetched && value_lazy (var->value))
1357 /* This is a frozen varobj and the value was never read.
1358 Presumably, UI shows some "never read" indicator.
1359 Now that we've fetched the real value, we need to report
1360 this varobj as changed so that UI can show the real
1364 else if (var->value == NULL && value == NULL)
1367 else if (var->value == NULL || value == NULL)
1373 gdb_assert (!value_lazy (var->value));
1374 gdb_assert (!value_lazy (value));
1376 gdb_assert (!var->print_value.empty () && !print_value.empty ());
1377 if (var->print_value != print_value)
1383 if (!initial && !changeable)
1385 /* For values that are not changeable, we don't compare the values.
1386 However, we want to notice if a value was not NULL and now is NULL,
1387 or vise versa, so that we report when top-level varobjs come in scope
1388 and leave the scope. */
1389 changed = (var->value != NULL) != (value != NULL);
1392 /* We must always keep the new value, since children depend on it. */
1393 if (var->value != NULL && var->value != value)
1394 value_free (var->value);
1396 if (value && value_lazy (value) && intentionally_not_fetched)
1397 var->not_fetched = true;
1399 var->not_fetched = false;
1400 var->updated = false;
1402 install_new_value_visualizer (var);
1404 /* If we installed a pretty-printer, re-compare the printed version
1405 to see if the variable changed. */
1406 if (var->dynamic->pretty_printer != NULL)
1408 print_value = varobj_value_get_print_value (var->value, var->format,
1410 if ((var->print_value.empty () && !print_value.empty ())
1411 || (!var->print_value.empty () && print_value.empty ())
1412 || (!var->print_value.empty () && !print_value.empty ()
1413 && var->print_value != print_value))
1416 var->print_value = print_value;
1418 gdb_assert (!var->value || value_type (var->value));
1423 /* Return the requested range for a varobj. VAR is the varobj. FROM
1424 and TO are out parameters; *FROM and *TO will be set to the
1425 selected sub-range of VAR. If no range was selected using
1426 -var-set-update-range, then both will be -1. */
1428 varobj_get_child_range (const struct varobj *var, int *from, int *to)
1434 /* Set the selected sub-range of children of VAR to start at index
1435 FROM and end at index TO. If either FROM or TO is less than zero,
1436 this is interpreted as a request for all children. */
1438 varobj_set_child_range (struct varobj *var, int from, int to)
1445 varobj_set_visualizer (struct varobj *var, const char *visualizer)
1450 if (!gdb_python_initialized)
1453 gdbpy_enter_varobj enter_py (var);
1455 mainmod = PyImport_AddModule ("__main__");
1456 gdbpy_ref<> globals (PyModule_GetDict (mainmod));
1457 Py_INCREF (globals.get ());
1459 gdbpy_ref<> constructor (PyRun_String (visualizer, Py_eval_input,
1460 globals.get (), globals.get ()));
1462 if (constructor == NULL)
1464 gdbpy_print_stack ();
1465 error (_("Could not evaluate visualizer expression: %s"), visualizer);
1468 construct_visualizer (var, constructor.get ());
1470 /* If there are any children now, wipe them. */
1471 varobj_delete (var, 1 /* children only */);
1472 var->num_children = -1;
1474 error (_("Python support required"));
1478 /* If NEW_VALUE is the new value of the given varobj (var), return
1479 true if var has mutated. In other words, if the type of
1480 the new value is different from the type of the varobj's old
1483 NEW_VALUE may be NULL, if the varobj is now out of scope. */
1486 varobj_value_has_mutated (const struct varobj *var, struct value *new_value,
1487 struct type *new_type)
1489 /* If we haven't previously computed the number of children in var,
1490 it does not matter from the front-end's perspective whether
1491 the type has mutated or not. For all intents and purposes,
1492 it has not mutated. */
1493 if (var->num_children < 0)
1496 if (var->root->lang_ops->value_has_mutated != NULL)
1498 /* The varobj module, when installing new values, explicitly strips
1499 references, saying that we're not interested in those addresses.
1500 But detection of mutation happens before installing the new
1501 value, so our value may be a reference that we need to strip
1502 in order to remain consistent. */
1503 if (new_value != NULL)
1504 new_value = coerce_ref (new_value);
1505 return var->root->lang_ops->value_has_mutated (var, new_value, new_type);
1511 /* Update the values for a variable and its children. This is a
1512 two-pronged attack. First, re-parse the value for the root's
1513 expression to see if it's changed. Then go all the way
1514 through its children, reconstructing them and noting if they've
1517 The IS_EXPLICIT parameter specifies if this call is result
1518 of MI request to update this specific variable, or
1519 result of implicit -var-update *. For implicit request, we don't
1520 update frozen variables.
1522 NOTE: This function may delete the caller's varobj. If it
1523 returns TYPE_CHANGED, then it has done this and VARP will be modified
1524 to point to the new varobj. */
1526 std::vector<varobj_update_result>
1527 varobj_update (struct varobj **varp, bool is_explicit)
1529 bool type_changed = false;
1530 struct value *newobj;
1531 std::vector<varobj_update_result> stack;
1532 std::vector<varobj_update_result> result;
1534 /* Frozen means frozen -- we don't check for any change in
1535 this varobj, including its going out of scope, or
1536 changing type. One use case for frozen varobjs is
1537 retaining previously evaluated expressions, and we don't
1538 want them to be reevaluated at all. */
1539 if (!is_explicit && (*varp)->frozen)
1542 if (!(*varp)->root->is_valid)
1544 result.emplace_back (*varp, VAROBJ_INVALID);
1548 if ((*varp)->root->rootvar == *varp)
1550 varobj_update_result r (*varp);
1552 /* Update the root variable. value_of_root can return NULL
1553 if the variable is no longer around, i.e. we stepped out of
1554 the frame in which a local existed. We are letting the
1555 value_of_root variable dispose of the varobj if the type
1557 newobj = value_of_root (varp, &type_changed);
1558 if (update_type_if_necessary (*varp, newobj))
1559 type_changed = true;
1561 r.type_changed = type_changed;
1562 if (install_new_value ((*varp), newobj, type_changed))
1566 r.status = VAROBJ_NOT_IN_SCOPE;
1567 r.value_installed = true;
1569 if (r.status == VAROBJ_NOT_IN_SCOPE)
1571 if (r.type_changed || r.changed)
1572 result.push_back (std::move (r));
1577 stack.push_back (std::move (r));
1580 stack.emplace_back (*varp);
1582 /* Walk through the children, reconstructing them all. */
1583 while (!stack.empty ())
1585 varobj_update_result r = std::move (stack.back ());
1587 struct varobj *v = r.varobj;
1589 /* Update this variable, unless it's a root, which is already
1591 if (!r.value_installed)
1593 struct type *new_type;
1595 newobj = value_of_child (v->parent, v->index);
1596 if (update_type_if_necessary (v, newobj))
1597 r.type_changed = true;
1599 new_type = value_type (newobj);
1601 new_type = v->root->lang_ops->type_of_child (v->parent, v->index);
1603 if (varobj_value_has_mutated (v, newobj, new_type))
1605 /* The children are no longer valid; delete them now.
1606 Report the fact that its type changed as well. */
1607 varobj_delete (v, 1 /* only_children */);
1608 v->num_children = -1;
1612 r.type_changed = true;
1615 if (install_new_value (v, newobj, r.type_changed))
1622 /* We probably should not get children of a dynamic varobj, but
1623 for which -var-list-children was never invoked. */
1624 if (varobj_is_dynamic_p (v))
1626 std::vector<varobj *> changed, type_changed, unchanged, newobj;
1627 bool children_changed = false;
1632 if (!v->dynamic->children_requested)
1636 /* If we initially did not have potential children, but
1637 now we do, consider the varobj as changed.
1638 Otherwise, if children were never requested, consider
1639 it as unchanged -- presumably, such varobj is not yet
1640 expanded in the UI, so we need not bother getting
1642 if (!varobj_has_more (v, 0))
1644 update_dynamic_varobj_children (v, NULL, NULL, NULL, NULL,
1645 &dummy, false, 0, 0);
1646 if (varobj_has_more (v, 0))
1651 result.push_back (std::move (r));
1656 /* If update_dynamic_varobj_children returns false, then we have
1657 a non-conforming pretty-printer, so we skip it. */
1658 if (update_dynamic_varobj_children (v, &changed, &type_changed, &newobj,
1659 &unchanged, &children_changed, true,
1662 if (children_changed || !newobj.empty ())
1664 r.children_changed = true;
1665 r.newobj = std::move (newobj);
1667 /* Push in reverse order so that the first child is
1668 popped from the work stack first, and so will be
1669 added to result first. This does not affect
1670 correctness, just "nicer". */
1671 for (int i = type_changed.size () - 1; i >= 0; --i)
1673 varobj_update_result r (type_changed[i]);
1675 /* Type may change only if value was changed. */
1677 r.type_changed = true;
1678 r.value_installed = true;
1680 stack.push_back (std::move (r));
1682 for (int i = changed.size () - 1; i >= 0; --i)
1684 varobj_update_result r (changed[i]);
1687 r.value_installed = true;
1689 stack.push_back (std::move (r));
1691 for (int i = unchanged.size () - 1; i >= 0; --i)
1693 if (!unchanged[i]->frozen)
1695 varobj_update_result r (unchanged[i]);
1697 r.value_installed = true;
1699 stack.push_back (std::move (r));
1702 if (r.changed || r.children_changed)
1703 result.push_back (std::move (r));
1709 /* Push any children. Use reverse order so that the first
1710 child is popped from the work stack first, and so
1711 will be added to result first. This does not
1712 affect correctness, just "nicer". */
1713 for (int i = v->children.size () - 1; i >= 0; --i)
1715 varobj *c = v->children[i];
1717 /* Child may be NULL if explicitly deleted by -var-delete. */
1718 if (c != NULL && !c->frozen)
1719 stack.emplace_back (c);
1722 if (r.changed || r.type_changed)
1723 result.push_back (std::move (r));
1729 /* Helper functions */
1732 * Variable object construction/destruction
1736 delete_variable (struct varobj *var, bool only_children_p)
1740 delete_variable_1 (&delcount, var, only_children_p,
1741 true /* remove_from_parent_p */ );
1746 /* Delete the variable object VAR and its children. */
1747 /* IMPORTANT NOTE: If we delete a variable which is a child
1748 and the parent is not removed we dump core. It must be always
1749 initially called with remove_from_parent_p set. */
1751 delete_variable_1 (int *delcountp, struct varobj *var, bool only_children_p,
1752 bool remove_from_parent_p)
1754 /* Delete any children of this variable, too. */
1755 for (varobj *child : var->children)
1760 if (!remove_from_parent_p)
1761 child->parent = NULL;
1763 delete_variable_1 (delcountp, child, false, only_children_p);
1765 var->children.clear ();
1767 /* if we were called to delete only the children we are done here. */
1768 if (only_children_p)
1771 /* Otherwise, add it to the list of deleted ones and proceed to do so. */
1772 /* If the name is empty, this is a temporary variable, that has not
1773 yet been installed, don't report it, it belongs to the caller... */
1774 if (!var->obj_name.empty ())
1776 *delcountp = *delcountp + 1;
1779 /* If this variable has a parent, remove it from its parent's list. */
1780 /* OPTIMIZATION: if the parent of this variable is also being deleted,
1781 (as indicated by remove_from_parent_p) we don't bother doing an
1782 expensive list search to find the element to remove when we are
1783 discarding the list afterwards. */
1784 if ((remove_from_parent_p) && (var->parent != NULL))
1785 var->parent->children[var->index] = NULL;
1787 if (!var->obj_name.empty ())
1788 uninstall_variable (var);
1790 /* Free memory associated with this variable. */
1794 /* Install the given variable VAR with the object name VAR->OBJ_NAME. */
1796 install_variable (struct varobj *var)
1799 struct vlist *newvl;
1801 unsigned int index = 0;
1804 for (chp = var->obj_name.c_str (); *chp; chp++)
1806 index = (index + (i++ * (unsigned int) *chp)) % VAROBJ_TABLE_SIZE;
1809 cv = *(varobj_table + index);
1810 while (cv != NULL && cv->var->obj_name != var->obj_name)
1814 error (_("Duplicate variable object name"));
1816 /* Add varobj to hash table. */
1817 newvl = XNEW (struct vlist);
1818 newvl->next = *(varobj_table + index);
1820 *(varobj_table + index) = newvl;
1822 /* If root, add varobj to root list. */
1823 if (is_root_p (var))
1825 /* Add to list of root variables. */
1826 if (rootlist == NULL)
1827 var->root->next = NULL;
1829 var->root->next = rootlist;
1830 rootlist = var->root;
1833 return true; /* OK */
1836 /* Unistall the object VAR. */
1838 uninstall_variable (struct varobj *var)
1842 struct varobj_root *cr;
1843 struct varobj_root *prer;
1845 unsigned int index = 0;
1848 /* Remove varobj from hash table. */
1849 for (chp = var->obj_name.c_str (); *chp; chp++)
1851 index = (index + (i++ * (unsigned int) *chp)) % VAROBJ_TABLE_SIZE;
1854 cv = *(varobj_table + index);
1856 while (cv != NULL && cv->var->obj_name != var->obj_name)
1863 fprintf_unfiltered (gdb_stdlog, "Deleting %s\n", var->obj_name.c_str ());
1868 ("Assertion failed: Could not find variable object \"%s\" to delete",
1869 var->obj_name.c_str ());
1874 *(varobj_table + index) = cv->next;
1876 prev->next = cv->next;
1880 /* If root, remove varobj from root list. */
1881 if (is_root_p (var))
1883 /* Remove from list of root variables. */
1884 if (rootlist == var->root)
1885 rootlist = var->root->next;
1890 while ((cr != NULL) && (cr->rootvar != var))
1897 warning (_("Assertion failed: Could not find "
1898 "varobj \"%s\" in root list"),
1899 var->obj_name.c_str ());
1905 prer->next = cr->next;
1911 /* Create and install a child of the parent of the given name.
1913 The created VAROBJ takes ownership of the allocated NAME. */
1915 static struct varobj *
1916 create_child (struct varobj *parent, int index, std::string &name)
1918 struct varobj_item item;
1920 std::swap (item.name, name);
1921 item.value = value_of_child (parent, index);
1923 return create_child_with_value (parent, index, &item);
1926 static struct varobj *
1927 create_child_with_value (struct varobj *parent, int index,
1928 struct varobj_item *item)
1930 varobj *child = new varobj (parent->root);
1932 /* NAME is allocated by caller. */
1933 std::swap (child->name, item->name);
1934 child->index = index;
1935 child->parent = parent;
1937 if (varobj_is_anonymous_child (child))
1938 child->obj_name = string_printf ("%s.%d_anonymous",
1939 parent->obj_name.c_str (), index);
1941 child->obj_name = string_printf ("%s.%s",
1942 parent->obj_name.c_str (),
1943 child->name.c_str ());
1945 install_variable (child);
1947 /* Compute the type of the child. Must do this before
1948 calling install_new_value. */
1949 if (item->value != NULL)
1950 /* If the child had no evaluation errors, var->value
1951 will be non-NULL and contain a valid type. */
1952 child->type = value_actual_type (item->value, 0, NULL);
1954 /* Otherwise, we must compute the type. */
1955 child->type = (*child->root->lang_ops->type_of_child) (child->parent,
1957 install_new_value (child, item->value, 1);
1964 * Miscellaneous utility functions.
1967 /* Allocate memory and initialize a new variable. */
1968 varobj::varobj (varobj_root *root_)
1969 : root (root_), dynamic (new varobj_dynamic)
1973 /* Free any allocated memory associated with VAR. */
1980 if (var->dynamic->pretty_printer != NULL)
1982 gdbpy_enter_varobj enter_py (var);
1984 Py_XDECREF (var->dynamic->constructor);
1985 Py_XDECREF (var->dynamic->pretty_printer);
1989 varobj_iter_delete (var->dynamic->child_iter);
1990 varobj_clear_saved_item (var->dynamic);
1991 value_free (var->value);
1993 if (is_root_p (var))
1996 delete var->dynamic;
1999 /* Return the type of the value that's stored in VAR,
2000 or that would have being stored there if the
2001 value were accessible.
2003 This differs from VAR->type in that VAR->type is always
2004 the true type of the expession in the source language.
2005 The return value of this function is the type we're
2006 actually storing in varobj, and using for displaying
2007 the values and for comparing previous and new values.
2009 For example, top-level references are always stripped. */
2011 varobj_get_value_type (const struct varobj *var)
2016 type = value_type (var->value);
2020 type = check_typedef (type);
2022 if (TYPE_IS_REFERENCE (type))
2023 type = get_target_type (type);
2025 type = check_typedef (type);
2030 /* What is the default display for this variable? We assume that
2031 everything is "natural". Any exceptions? */
2032 static enum varobj_display_formats
2033 variable_default_display (struct varobj *var)
2035 return FORMAT_NATURAL;
2039 * Language-dependencies
2042 /* Common entry points */
2044 /* Return the number of children for a given variable.
2045 The result of this function is defined by the language
2046 implementation. The number of children returned by this function
2047 is the number of children that the user will see in the variable
2050 number_of_children (const struct varobj *var)
2052 return (*var->root->lang_ops->number_of_children) (var);
2055 /* What is the expression for the root varobj VAR? */
2058 name_of_variable (const struct varobj *var)
2060 return (*var->root->lang_ops->name_of_variable) (var);
2063 /* What is the name of the INDEX'th child of VAR? */
2066 name_of_child (struct varobj *var, int index)
2068 return (*var->root->lang_ops->name_of_child) (var, index);
2071 /* If frame associated with VAR can be found, switch
2072 to it and return true. Otherwise, return false. */
2075 check_scope (const struct varobj *var)
2077 struct frame_info *fi;
2080 fi = frame_find_by_id (var->root->frame);
2085 CORE_ADDR pc = get_frame_pc (fi);
2087 if (pc < BLOCK_START (var->root->valid_block) ||
2088 pc >= BLOCK_END (var->root->valid_block))
2096 /* Helper function to value_of_root. */
2098 static struct value *
2099 value_of_root_1 (struct varobj **var_handle)
2101 struct value *new_val = NULL;
2102 struct varobj *var = *var_handle;
2103 bool within_scope = false;
2105 /* Only root variables can be updated... */
2106 if (!is_root_p (var))
2107 /* Not a root var. */
2110 scoped_restore_current_thread restore_thread;
2112 /* Determine whether the variable is still around. */
2113 if (var->root->valid_block == NULL || var->root->floating)
2114 within_scope = true;
2115 else if (var->root->thread_id == 0)
2117 /* The program was single-threaded when the variable object was
2118 created. Technically, it's possible that the program became
2119 multi-threaded since then, but we don't support such
2121 within_scope = check_scope (var);
2125 ptid_t ptid = global_thread_id_to_ptid (var->root->thread_id);
2127 if (!ptid_equal (minus_one_ptid, ptid))
2129 switch_to_thread (ptid);
2130 within_scope = check_scope (var);
2137 /* We need to catch errors here, because if evaluate
2138 expression fails we want to just return NULL. */
2141 new_val = evaluate_expression (var->root->exp.get ());
2143 CATCH (except, RETURN_MASK_ERROR)
2152 /* What is the ``struct value *'' of the root variable VAR?
2153 For floating variable object, evaluation can get us a value
2154 of different type from what is stored in varobj already. In
2156 - *type_changed will be set to 1
2157 - old varobj will be freed, and new one will be
2158 created, with the same name.
2159 - *var_handle will be set to the new varobj
2160 Otherwise, *type_changed will be set to 0. */
2161 static struct value *
2162 value_of_root (struct varobj **var_handle, bool *type_changed)
2166 if (var_handle == NULL)
2171 /* This should really be an exception, since this should
2172 only get called with a root variable. */
2174 if (!is_root_p (var))
2177 if (var->root->floating)
2179 struct varobj *tmp_var;
2181 tmp_var = varobj_create (NULL, var->name.c_str (), (CORE_ADDR) 0,
2182 USE_SELECTED_FRAME);
2183 if (tmp_var == NULL)
2187 std::string old_type = varobj_get_type (var);
2188 std::string new_type = varobj_get_type (tmp_var);
2189 if (old_type == new_type)
2191 /* The expression presently stored inside var->root->exp
2192 remembers the locations of local variables relatively to
2193 the frame where the expression was created (in DWARF location
2194 button, for example). Naturally, those locations are not
2195 correct in other frames, so update the expression. */
2197 std::swap (var->root->exp, tmp_var->root->exp);
2199 varobj_delete (tmp_var, 0);
2204 tmp_var->obj_name = var->obj_name;
2205 tmp_var->from = var->from;
2206 tmp_var->to = var->to;
2207 varobj_delete (var, 0);
2209 install_variable (tmp_var);
2210 *var_handle = tmp_var;
2212 *type_changed = true;
2221 struct value *value;
2223 value = value_of_root_1 (var_handle);
2224 if (var->value == NULL || value == NULL)
2226 /* For root varobj-s, a NULL value indicates a scoping issue.
2227 So, nothing to do in terms of checking for mutations. */
2229 else if (varobj_value_has_mutated (var, value, value_type (value)))
2231 /* The type has mutated, so the children are no longer valid.
2232 Just delete them, and tell our caller that the type has
2234 varobj_delete (var, 1 /* only_children */);
2235 var->num_children = -1;
2238 *type_changed = true;
2244 /* What is the ``struct value *'' for the INDEX'th child of PARENT? */
2245 static struct value *
2246 value_of_child (const struct varobj *parent, int index)
2248 struct value *value;
2250 value = (*parent->root->lang_ops->value_of_child) (parent, index);
2255 /* GDB already has a command called "value_of_variable". Sigh. */
2257 my_value_of_variable (struct varobj *var, enum varobj_display_formats format)
2259 if (var->root->is_valid)
2261 if (var->dynamic->pretty_printer != NULL)
2262 return varobj_value_get_print_value (var->value, var->format, var);
2263 return (*var->root->lang_ops->value_of_variable) (var, format);
2266 return std::string ();
2270 varobj_formatted_print_options (struct value_print_options *opts,
2271 enum varobj_display_formats format)
2273 get_formatted_print_options (opts, format_code[(int) format]);
2274 opts->deref_ref = 0;
2279 varobj_value_get_print_value (struct value *value,
2280 enum varobj_display_formats format,
2281 const struct varobj *var)
2283 struct value_print_options opts;
2284 struct type *type = NULL;
2286 gdb::unique_xmalloc_ptr<char> encoding;
2287 /* Initialize it just to avoid a GCC false warning. */
2288 CORE_ADDR str_addr = 0;
2289 bool string_print = false;
2292 return std::string ();
2295 std::string thevalue;
2298 if (gdb_python_initialized)
2300 PyObject *value_formatter = var->dynamic->pretty_printer;
2302 gdbpy_enter_varobj enter_py (var);
2304 if (value_formatter)
2306 /* First check to see if we have any children at all. If so,
2307 we simply return {...}. */
2308 if (dynamic_varobj_has_child_method (var))
2311 if (PyObject_HasAttr (value_formatter, gdbpy_to_string_cst))
2313 struct value *replacement;
2315 gdbpy_ref<> output (apply_varobj_pretty_printer (value_formatter,
2319 /* If we have string like output ... */
2322 /* If this is a lazy string, extract it. For lazy
2323 strings we always print as a string, so set
2325 if (gdbpy_is_lazy_string (output.get ()))
2327 gdbpy_extract_lazy_string (output.get (), &str_addr,
2328 &type, &len, &encoding);
2329 string_print = true;
2333 /* If it is a regular (non-lazy) string, extract
2334 it and copy the contents into THEVALUE. If the
2335 hint says to print it as a string, set
2336 string_print. Otherwise just return the extracted
2337 string as a value. */
2339 gdb::unique_xmalloc_ptr<char> s
2340 = python_string_to_target_string (output.get ());
2344 struct gdbarch *gdbarch;
2346 gdb::unique_xmalloc_ptr<char> hint
2347 = gdbpy_get_display_hint (value_formatter);
2350 if (!strcmp (hint.get (), "string"))
2351 string_print = true;
2354 thevalue = std::string (s.get ());
2355 len = thevalue.size ();
2356 gdbarch = get_type_arch (value_type (value));
2357 type = builtin_type (gdbarch)->builtin_char;
2363 gdbpy_print_stack ();
2366 /* If the printer returned a replacement value, set VALUE
2367 to REPLACEMENT. If there is not a replacement value,
2368 just use the value passed to this function. */
2370 value = replacement;
2376 varobj_formatted_print_options (&opts, format);
2378 /* If the THEVALUE has contents, it is a regular string. */
2379 if (!thevalue.empty ())
2380 LA_PRINT_STRING (&stb, type, (gdb_byte *) thevalue.c_str (),
2381 len, encoding.get (), 0, &opts);
2382 else if (string_print)
2383 /* Otherwise, if string_print is set, and it is not a regular
2384 string, it is a lazy string. */
2385 val_print_string (type, encoding.get (), str_addr, len, &stb, &opts);
2387 /* All other cases. */
2388 common_val_print (value, &stb, 0, &opts, current_language);
2390 return std::move (stb.string ());
2394 varobj_editable_p (const struct varobj *var)
2398 if (!(var->root->is_valid && var->value && VALUE_LVAL (var->value)))
2401 type = varobj_get_value_type (var);
2403 switch (TYPE_CODE (type))
2405 case TYPE_CODE_STRUCT:
2406 case TYPE_CODE_UNION:
2407 case TYPE_CODE_ARRAY:
2408 case TYPE_CODE_FUNC:
2409 case TYPE_CODE_METHOD:
2419 /* Call VAR's value_is_changeable_p language-specific callback. */
2422 varobj_value_is_changeable_p (const struct varobj *var)
2424 return var->root->lang_ops->value_is_changeable_p (var);
2427 /* Return true if that varobj is floating, that is is always evaluated in the
2428 selected frame, and not bound to thread/frame. Such variable objects
2429 are created using '@' as frame specifier to -var-create. */
2431 varobj_floating_p (const struct varobj *var)
2433 return var->root->floating;
2436 /* Implement the "value_is_changeable_p" varobj callback for most
2440 varobj_default_value_is_changeable_p (const struct varobj *var)
2445 if (CPLUS_FAKE_CHILD (var))
2448 type = varobj_get_value_type (var);
2450 switch (TYPE_CODE (type))
2452 case TYPE_CODE_STRUCT:
2453 case TYPE_CODE_UNION:
2454 case TYPE_CODE_ARRAY:
2465 /* Iterate all the existing _root_ VAROBJs and call the FUNC callback for them
2466 with an arbitrary caller supplied DATA pointer. */
2469 all_root_varobjs (void (*func) (struct varobj *var, void *data), void *data)
2471 struct varobj_root *var_root, *var_root_next;
2473 /* Iterate "safely" - handle if the callee deletes its passed VAROBJ. */
2475 for (var_root = rootlist; var_root != NULL; var_root = var_root_next)
2477 var_root_next = var_root->next;
2479 (*func) (var_root->rootvar, data);
2483 /* Invalidate varobj VAR if it is tied to locals and re-create it if it is
2484 defined on globals. It is a helper for varobj_invalidate.
2486 This function is called after changing the symbol file, in this case the
2487 pointers to "struct type" stored by the varobj are no longer valid. All
2488 varobj must be either re-evaluated, or marked as invalid here. */
2491 varobj_invalidate_iter (struct varobj *var, void *unused)
2493 /* global and floating var must be re-evaluated. */
2494 if (var->root->floating || var->root->valid_block == NULL)
2496 struct varobj *tmp_var;
2498 /* Try to create a varobj with same expression. If we succeed
2499 replace the old varobj, otherwise invalidate it. */
2500 tmp_var = varobj_create (NULL, var->name.c_str (), (CORE_ADDR) 0,
2502 if (tmp_var != NULL)
2504 tmp_var->obj_name = var->obj_name;
2505 varobj_delete (var, 0);
2506 install_variable (tmp_var);
2509 var->root->is_valid = false;
2511 else /* locals must be invalidated. */
2512 var->root->is_valid = false;
2515 /* Invalidate the varobjs that are tied to locals and re-create the ones that
2516 are defined on globals.
2517 Invalidated varobjs will be always printed in_scope="invalid". */
2520 varobj_invalidate (void)
2522 all_root_varobjs (varobj_invalidate_iter, NULL);
2526 _initialize_varobj (void)
2528 varobj_table = XCNEWVEC (struct vlist *, VAROBJ_TABLE_SIZE);
2530 add_setshow_zuinteger_cmd ("varobj", class_maintenance,
2532 _("Set varobj debugging."),
2533 _("Show varobj debugging."),
2534 _("When non-zero, varobj debugging is enabled."),
2535 NULL, show_varobjdebug,
2536 &setdebuglist, &showdebuglist);