gdb/varobj.h

   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 */
  25 enum 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
  35 enum 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.  */
  43 enum 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).  */
  54 extern const char *varobj_format_string[];
  55
  56 /* Struct that describes a variable object instance.  */
  57
  58 struct varobj;
  59
  60 typedef struct varobj *varobj_p;
  61 DEF_VEC_P (varobj_p);
  62
  63 typedef 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
  82 DEF_VEC_O (varobj_update_result);
  83
  84 struct varobj_root;
  85 struct 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.  */
  90 struct varobj
  91 {
  92   explicit varobj (varobj_root *root_);
  93   ~varobj ();
  94
  95   /* Name of the variable for this object.  If this variable is a
  96      child, then this name will be the child's source name.
  97      (bar, not foo.bar).  */
  98   /* NOTE: This is the "expression".  */
  99   std::string name;
 100
 101   /* Expression for this child.  Can be used to create a root variable
 102      corresponding to this child.  */
 103   std::string path_expr;
 104
 105   /* The name for this variable's object.  This is here for
 106      convenience when constructing this object's children.  */
 107   std::string obj_name;
 108
 109   /* Index of this variable in its parent or -1.  */
 110   int index = -1;
 111
 112   /* The type of this variable.  This can be NULL
 113      for artificial variable objects -- currently, the "accessibility"
 114      variable objects in C++.  */
 115   struct type *type = NULL;
 116
 117   /* The value of this expression or subexpression.  A NULL value
 118      indicates there was an error getting this value.
 119      Invariant: if varobj_value_is_changeable_p (this) is non-zero,
 120      the value is either NULL, or not lazy.  */
 121   struct value *value = NULL;
 122
 123   /* The number of (immediate) children this variable has.  */
 124   int num_children = -1;
 125
 126   /* If this object is a child, this points to its immediate parent.  */
 127   const struct varobj *parent = NULL;
 128
 129   /* Children of this object.  */
 130   VEC (varobj_p) *children = NULL;
 131
 132   /* Description of the root variable.  Points to root variable for
 133      children.  */
 134   struct varobj_root *root;
 135
 136   /* The format of the output for this object.  */
 137   enum varobj_display_formats format = FORMAT_NATURAL;
 138
 139   /* Was this variable updated via a varobj_set_value operation.  */
 140   int updated = 0;
 141
 142   /* Last print value.  */
 143   std::string print_value;
 144
 145   /* Is this variable frozen.  Frozen variables are never implicitly
 146      updated by -var-update *
 147      or -var-update <direct-or-indirect-parent>.  */
 148   int frozen = 0;
 149
 150   /* Is the value of this variable intentionally not fetched?  It is
 151      not fetched if either the variable is frozen, or any parents is
 152      frozen.  */
 153   int not_fetched = 0;
 154
 155   /* Sub-range of children which the MI consumer has requested.  If
 156      FROM < 0 or TO < 0, means that all children have been
 157      requested.  */
 158   int from = -1;
 159   int to = -1;
 160
 161   /* Dynamic part of varobj.  */
 162   struct varobj_dynamic *dynamic;
 163 };
 164
 165 /* Is the variable X one of our "fake" children?  */
 166 #define CPLUS_FAKE_CHILD(x) \
 167 ((x) != NULL && (x)->type == NULL && (x)->value == NULL)
 168
 169 /* The language specific vector */
 170
 171 struct lang_varobj_ops
 172 {
 173   /* The number of children of PARENT.  */
 174   int (*number_of_children) (const struct varobj *parent);
 175
 176   /* The name (expression) of a root varobj.  */
 177   std::string (*name_of_variable) (const struct varobj *parent);
 178
 179   /* The name of the INDEX'th child of PARENT.  */
 180   std::string (*name_of_child) (const struct varobj *parent, int index);
 181
 182   /* Returns the rooted expression of CHILD, which is a variable
 183      obtain that has some parent.  */
 184   std::string (*path_expr_of_child) (const struct varobj *child);
 185
 186   /* The ``struct value *'' of the INDEX'th child of PARENT.  */
 187   struct value *(*value_of_child) (const struct varobj *parent, int index);
 188
 189   /* The type of the INDEX'th child of PARENT.  */
 190   struct type *(*type_of_child) (const struct varobj *parent, int index);
 191
 192   /* The current value of VAR.  */
 193   std::string (*value_of_variable) (const struct varobj *var,
 194                                     enum varobj_display_formats format);
 195
 196   /* Return non-zero if changes in value of VAR must be detected and
 197      reported by -var-update.  Return zero if -var-update should never
 198      report changes of such values.  This makes sense for structures
 199      (since the changes in children values will be reported separately),
 200      or for artificial objects (like 'public' pseudo-field in C++).
 201
 202      Return value of 0 means that gdb need not call value_fetch_lazy
 203      for the value of this variable object.  */
 204   int (*value_is_changeable_p) (const struct varobj *var);
 205
 206   /* Return nonzero if the type of VAR has mutated.
 207
 208      VAR's value is still the varobj's previous value, while NEW_VALUE
 209      is VAR's new value and NEW_TYPE is the var's new type.  NEW_VALUE
 210      may be NULL indicating that there is no value available (the varobj
 211      may be out of scope, of may be the child of a null pointer, for
 212      instance).  NEW_TYPE, on the other hand, must never be NULL.
 213
 214      This function should also be able to assume that var's number of
 215      children is set (not < 0).
 216
 217      Languages where types do not mutate can set this to NULL.  */
 218   int (*value_has_mutated) (const struct varobj *var, struct value *new_value,
 219                             struct type *new_type);
 220
 221   /* Return nonzero if VAR is a suitable path expression parent.
 222
 223      For C like languages with anonymous structures and unions an anonymous
 224      structure or union is not a suitable parent.  */
 225   int (*is_path_expr_parent) (const struct varobj *var);
 226 };
 227
 228 extern const struct lang_varobj_ops c_varobj_ops;
 229 extern const struct lang_varobj_ops cplus_varobj_ops;
 230 extern const struct lang_varobj_ops ada_varobj_ops;
 231
 232 #define default_varobj_ops c_varobj_ops
 233 /* API functions */
 234
 235 extern struct varobj *varobj_create (const char *objname,
 236                                      const char *expression, CORE_ADDR frame,
 237                                      enum varobj_type type);
 238
 239 extern std::string varobj_gen_name (void);
 240
 241 extern struct varobj *varobj_get_handle (const char *name);
 242
 243 extern const char *varobj_get_objname (const struct varobj *var);
 244
 245 extern std::string varobj_get_expression (const struct varobj *var);
 246
 247 /* Delete a varobj and all its children if only_children == 0, otherwise delete
 248    only the children.  Return the number of deleted variables.  */
 249
 250 extern int varobj_delete (struct varobj *var, int only_children);
 251
 252 extern enum varobj_display_formats varobj_set_display_format (
 253                                                          struct varobj *var,
 254                                         enum varobj_display_formats format);
 255
 256 extern enum varobj_display_formats varobj_get_display_format (
 257                                                 const struct varobj *var);
 258
 259 extern int varobj_get_thread_id (const struct varobj *var);
 260
 261 extern void varobj_set_frozen (struct varobj *var, int frozen);
 262
 263 extern int varobj_get_frozen (const struct varobj *var);
 264
 265 extern void varobj_get_child_range (const struct varobj *var, int *from,
 266                                     int *to);
 267
 268 extern void varobj_set_child_range (struct varobj *var, int from, int to);
 269
 270 extern gdb::unique_xmalloc_ptr<char>
 271      varobj_get_display_hint (const struct varobj *var);
 272
 273 extern int varobj_get_num_children (struct varobj *var);
 274
 275 /* Return the list of children of VAR.  The returned vector should not
 276    be modified in any way.  FROM and TO are in/out parameters
 277    indicating the range of children to return.  If either *FROM or *TO
 278    is less than zero on entry, then all children will be returned.  On
 279    return, *FROM and *TO will be updated to indicate the real range
 280    that was returned.  The resulting VEC will contain at least the
 281    children from *FROM to just before *TO; it might contain more
 282    children, depending on whether any more were available.  */
 283 extern VEC (varobj_p)* varobj_list_children (struct varobj *var,
 284                                              int *from, int *to);
 285
 286 extern std::string varobj_get_type (struct varobj *var);
 287
 288 extern struct type *varobj_get_gdb_type (const struct varobj *var);
 289
 290 extern const char *varobj_get_path_expr (const struct varobj *var);
 291
 292 extern const struct language_defn *
 293   varobj_get_language (const struct varobj *var);
 294
 295 extern int varobj_get_attributes (const struct varobj *var);
 296
 297 extern std::string
 298   varobj_get_formatted_value (struct varobj *var,
 299                               enum varobj_display_formats format);
 300
 301 extern std::string varobj_get_value (struct varobj *var);
 302
 303 extern int varobj_set_value (struct varobj *var, const char *expression);
 304
 305 extern void all_root_varobjs (void (*func) (struct varobj *var, void *data),
 306                               void *data);
 307
 308 extern VEC(varobj_update_result) *varobj_update (struct varobj **varp,
 309                                                  int is_explicit);
 310
 311 extern void varobj_invalidate (void);
 312
 313 extern int varobj_editable_p (const struct varobj *var);
 314
 315 extern int varobj_floating_p (const struct varobj *var);
 316
 317 extern void varobj_set_visualizer (struct varobj *var,
 318                                    const char *visualizer);
 319
 320 extern void varobj_enable_pretty_printing (void);
 321
 322 extern int varobj_has_more (const struct varobj *var, int to);
 323
 324 extern int varobj_is_dynamic_p (const struct varobj *var);
 325
 326 extern int varobj_default_value_is_changeable_p (const struct varobj *var);
 327 extern int varobj_value_is_changeable_p (const struct varobj *var);
 328
 329 extern struct type *varobj_get_value_type (const struct varobj *var);
 330
 331 extern int varobj_is_anonymous_child (const struct varobj *child);
 332
 333 extern const struct varobj *
 334   varobj_get_path_expr_parent (const struct varobj *var);
 335
 336 extern std::string
 337   varobj_value_get_print_value (struct value *value,
 338                                 enum varobj_display_formats format,
 339                                 const struct varobj *var);
 340
 341 extern void varobj_formatted_print_options (struct value_print_options *opts,
 342                                             enum varobj_display_formats format);
 343
 344 extern void varobj_restrict_range (VEC (varobj_p) *children, int *from,
 345                                    int *to);
 346
 347 extern int varobj_default_is_path_expr_parent (const struct varobj *var);
 348
 349 #endif /* VAROBJ_H */