varobj.h revision 1.7 
1/* GDB variable objects API.
2   Copyright (C) 1999-2017 Free Software Foundation, Inc.
3
4   This program is free software; you can redistribute it and/or modify
5   it under the terms of the GNU General Public License as published by
6   the Free Software Foundation; either version 3 of the License, or
7   (at your option) any later version.
8
9   This program is distributed in the hope that it will be useful,
10   but WITHOUT ANY WARRANTY; without even the implied warranty of
11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12   GNU General Public License for more details.
13
14   You should have received a copy of the GNU General Public License
15   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
16
17#ifndef VAROBJ_H
18#define VAROBJ_H 1
19
20#include "symtab.h"
21#include "gdbtypes.h"
22#include "vec.h"
23
24/* Enumeration for the format types */
25enum varobj_display_formats
26  {
27    FORMAT_NATURAL,		/* What gdb actually calls 'natural' */
28    FORMAT_BINARY,		/* Binary display                    */
29    FORMAT_DECIMAL,		/* Decimal display                   */
30    FORMAT_HEXADECIMAL,		/* Hex display                       */
31    FORMAT_OCTAL,		/* Octal display                     */
32    FORMAT_ZHEXADECIMAL		/* Zero padded hexadecimal	     */
33  };
34
35enum varobj_type
36  {
37    USE_SPECIFIED_FRAME,        /* Use the frame passed to varobj_create.  */
38    USE_CURRENT_FRAME,          /* Use the current frame.  */
39    USE_SELECTED_FRAME          /* Always reevaluate in selected frame.  */
40  };
41
42/* Enumerator describing if a variable object is in scope.  */
43enum varobj_scope_status
44  {
45    VAROBJ_IN_SCOPE = 0,        /* Varobj is scope, value available.  */
46    VAROBJ_NOT_IN_SCOPE = 1,    /* Varobj is not in scope, value not
47				   available, but varobj can become in
48				   scope later.  */
49    VAROBJ_INVALID = 2,         /* Varobj no longer has any value, and never
50				   will.  */
51  };
52
53/* String representations of gdb's format codes (defined in varobj.c).  */
54extern const char *varobj_format_string[];
55
56/* Struct that describes a variable object instance.  */
57
58struct varobj;
59
60typedef struct varobj *varobj_p;
61DEF_VEC_P (varobj_p);
62
63typedef struct varobj_update_result_t
64{
65  struct varobj *varobj;
66  int type_changed;
67  int children_changed;
68  int changed;
69  enum varobj_scope_status status;
70  /* This variable is used internally by varobj_update to indicate if the
71     new value of varobj is already computed and installed, or has to
72     be yet installed.  Don't use this outside varobj.c.  */
73  int value_installed;
74
75  /* This will be non-NULL when new children were added to the varobj.
76     It lists the new children (which must necessarily come at the end
77     of the child list) added during an update.  The caller is
78     responsible for freeing this vector.  */
79  VEC (varobj_p) *newobj;
80} varobj_update_result;
81
82DEF_VEC_O (varobj_update_result);
83
84struct varobj_root;
85struct varobj_dynamic;
86
87/* Every variable in the system has a structure of this type defined
88   for it.  This structure holds all information necessary to manipulate
89   a particular object variable.  */
90struct varobj
91{
92  /* Name of the variable for this object.  If this variable is a
93     child, then this name will be the child's source name.
94     (bar, not foo.bar).  */
95  /* NOTE: This is the "expression".  */
96  std::string name;
97
98  /* Expression for this child.  Can be used to create a root variable
99     corresponding to this child.  */
100  std::string path_expr;
101
102  /* The name for this variable's object.  This is here for
103     convenience when constructing this object's children.  */
104  std::string obj_name;
105
106  /* Index of this variable in its parent or -1.  */
107  int index;
108
109  /* The type of this variable.  This can be NULL
110     for artificial variable objects -- currently, the "accessibility"
111     variable objects in C++.  */
112  struct type *type;
113
114  /* The value of this expression or subexpression.  A NULL value
115     indicates there was an error getting this value.
116     Invariant: if varobj_value_is_changeable_p (this) is non-zero,
117     the value is either NULL, or not lazy.  */
118  struct value *value;
119
120  /* The number of (immediate) children this variable has.  */
121  int num_children;
122
123  /* If this object is a child, this points to its immediate parent.  */
124  const struct varobj *parent;
125
126  /* Children of this object.  */
127  VEC (varobj_p) *children;
128
129  /* Description of the root variable.  Points to root variable for
130     children.  */
131  struct varobj_root *root;
132
133  /* The format of the output for this object.  */
134  enum varobj_display_formats format;
135
136  /* Was this variable updated via a varobj_set_value operation.  */
137  int updated;
138
139  /* Last print value.  */
140  std::string print_value;
141
142  /* Is this variable frozen.  Frozen variables are never implicitly
143     updated by -var-update *
144     or -var-update <direct-or-indirect-parent>.  */
145  int frozen;
146
147  /* Is the value of this variable intentionally not fetched?  It is
148     not fetched if either the variable is frozen, or any parents is
149     frozen.  */
150  int not_fetched;
151
152  /* Sub-range of children which the MI consumer has requested.  If
153     FROM < 0 or TO < 0, means that all children have been
154     requested.  */
155  int from;
156  int to;
157
158  /* Dynamic part of varobj.  */
159  struct varobj_dynamic *dynamic;
160};
161
162/* Is the variable X one of our "fake" children?  */
163#define CPLUS_FAKE_CHILD(x) \
164((x) != NULL && (x)->type == NULL && (x)->value == NULL)
165
166/* The language specific vector */
167
168struct lang_varobj_ops
169{
170  /* The number of children of PARENT.  */
171  int (*number_of_children) (const struct varobj *parent);
172
173  /* The name (expression) of a root varobj.  */
174  std::string (*name_of_variable) (const struct varobj *parent);
175
176  /* The name of the INDEX'th child of PARENT.  */
177  std::string (*name_of_child) (const struct varobj *parent, int index);
178
179  /* Returns the rooted expression of CHILD, which is a variable
180     obtain that has some parent.  */
181  std::string (*path_expr_of_child) (const struct varobj *child);
182
183  /* The ``struct value *'' of the INDEX'th child of PARENT.  */
184  struct value *(*value_of_child) (const struct varobj *parent, int index);
185
186  /* The type of the INDEX'th child of PARENT.  */
187  struct type *(*type_of_child) (const struct varobj *parent, int index);
188
189  /* The current value of VAR.  */
190  std::string (*value_of_variable) (const struct varobj *var,
191				    enum varobj_display_formats format);
192
193  /* Return non-zero if changes in value of VAR must be detected and
194     reported by -var-update.  Return zero if -var-update should never
195     report changes of such values.  This makes sense for structures
196     (since the changes in children values will be reported separately),
197     or for artificial objects (like 'public' pseudo-field in C++).
198
199     Return value of 0 means that gdb need not call value_fetch_lazy
200     for the value of this variable object.  */
201  int (*value_is_changeable_p) (const struct varobj *var);
202
203  /* Return nonzero if the type of VAR has mutated.
204
205     VAR's value is still the varobj's previous value, while NEW_VALUE
206     is VAR's new value and NEW_TYPE is the var's new type.  NEW_VALUE
207     may be NULL indicating that there is no value available (the varobj
208     may be out of scope, of may be the child of a null pointer, for
209     instance).  NEW_TYPE, on the other hand, must never be NULL.
210
211     This function should also be able to assume that var's number of
212     children is set (not < 0).
213
214     Languages where types do not mutate can set this to NULL.  */
215  int (*value_has_mutated) (const struct varobj *var, struct value *new_value,
216			    struct type *new_type);
217
218  /* Return nonzero if VAR is a suitable path expression parent.
219
220     For C like languages with anonymous structures and unions an anonymous
221     structure or union is not a suitable parent.  */
222  int (*is_path_expr_parent) (const struct varobj *var);
223};
224
225extern const struct lang_varobj_ops c_varobj_ops;
226extern const struct lang_varobj_ops cplus_varobj_ops;
227extern const struct lang_varobj_ops ada_varobj_ops;
228
229#define default_varobj_ops c_varobj_ops
230/* API functions */
231
232extern struct varobj *varobj_create (const char *objname,
233				     const char *expression, CORE_ADDR frame,
234				     enum varobj_type type);
235
236extern char *varobj_gen_name (void);
237
238extern struct varobj *varobj_get_handle (const char *name);
239
240extern const char *varobj_get_objname (const struct varobj *var);
241
242extern std::string varobj_get_expression (const struct varobj *var);
243
244/* Delete a varobj and all its children if only_children == 0, otherwise delete
245   only the children.  Return the number of deleted variables.  */
246
247extern int varobj_delete (struct varobj *var, int only_children);
248
249extern enum varobj_display_formats varobj_set_display_format (
250							 struct varobj *var,
251					enum varobj_display_formats format);
252
253extern enum varobj_display_formats varobj_get_display_format (
254						const struct varobj *var);
255
256extern int varobj_get_thread_id (const struct varobj *var);
257
258extern void varobj_set_frozen (struct varobj *var, int frozen);
259
260extern int varobj_get_frozen (const struct varobj *var);
261
262extern void varobj_get_child_range (const struct varobj *var, int *from,
263				    int *to);
264
265extern void varobj_set_child_range (struct varobj *var, int from, int to);
266
267extern gdb::unique_xmalloc_ptr<char>
268     varobj_get_display_hint (const struct varobj *var);
269
270extern int varobj_get_num_children (struct varobj *var);
271
272/* Return the list of children of VAR.  The returned vector should not
273   be modified in any way.  FROM and TO are in/out parameters
274   indicating the range of children to return.  If either *FROM or *TO
275   is less than zero on entry, then all children will be returned.  On
276   return, *FROM and *TO will be updated to indicate the real range
277   that was returned.  The resulting VEC will contain at least the
278   children from *FROM to just before *TO; it might contain more
279   children, depending on whether any more were available.  */
280extern VEC (varobj_p)* varobj_list_children (struct varobj *var,
281					     int *from, int *to);
282
283extern std::string varobj_get_type (struct varobj *var);
284
285extern struct type *varobj_get_gdb_type (const struct varobj *var);
286
287extern const char *varobj_get_path_expr (const struct varobj *var);
288
289extern const struct language_defn *
290  varobj_get_language (const struct varobj *var);
291
292extern int varobj_get_attributes (const struct varobj *var);
293
294extern std::string
295  varobj_get_formatted_value (struct varobj *var,
296			      enum varobj_display_formats format);
297
298extern std::string varobj_get_value (struct varobj *var);
299
300extern int varobj_set_value (struct varobj *var, const char *expression);
301
302extern void all_root_varobjs (void (*func) (struct varobj *var, void *data),
303			      void *data);
304
305extern VEC(varobj_update_result) *varobj_update (struct varobj **varp,
306						 int is_explicit);
307
308extern void varobj_invalidate (void);
309
310extern int varobj_editable_p (const struct varobj *var);
311
312extern int varobj_floating_p (const struct varobj *var);
313
314extern void varobj_set_visualizer (struct varobj *var,
315				   const char *visualizer);
316
317extern void varobj_enable_pretty_printing (void);
318
319extern int varobj_has_more (const struct varobj *var, int to);
320
321extern int varobj_is_dynamic_p (const struct varobj *var);
322
323extern int varobj_default_value_is_changeable_p (const struct varobj *var);
324extern int varobj_value_is_changeable_p (const struct varobj *var);
325
326extern struct type *varobj_get_value_type (const struct varobj *var);
327
328extern int varobj_is_anonymous_child (const struct varobj *child);
329
330extern const struct varobj *
331  varobj_get_path_expr_parent (const struct varobj *var);
332
333extern std::string
334  varobj_value_get_print_value (struct value *value,
335				enum varobj_display_formats format,
336				const struct varobj *var);
337
338extern void varobj_formatted_print_options (struct value_print_options *opts,
339					    enum varobj_display_formats format);
340
341extern void varobj_restrict_range (VEC (varobj_p) *children, int *from,
342				   int *to);
343
344extern int varobj_default_is_path_expr_parent (const struct varobj *var);
345
346#endif /* VAROBJ_H */
347