gdb/varobj.h

   1 /* GDB variable objects API.
   2    Copyright (C) 1999-2016 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 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.  Members which must be freed are noted.  */
  90 struct varobj
  91 {
  92   /* Alloc'd 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   char *name;
  97
  98   /* Alloc'd expression for this child.  Can be used to create a
  99      root variable corresponding to this child.  */
 100   char *path_expr;
 101
 102   /* The alloc'd name for this variable's object.  This is here for
 103      convenience when constructing this object's children.  */
 104   char *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   char *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
 168 struct 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.  The returned value must be freed
 174      by the caller.  */
 175   char *(*name_of_variable) (const struct varobj *parent);
 176
 177   /* The name of the INDEX'th child of PARENT.  The returned value must be
 178      freed by the caller.  */
 179   char *(*name_of_child) (const struct varobj *parent, int index);
 180
 181   /* Returns the rooted expression of CHILD, which is a variable
 182      obtain that has some parent.  The returned value must be freed by the
 183      caller.  */
 184   char *(*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.  The returned value must be freed by the
 193      caller.  */
 194   char *(*value_of_variable) (const struct varobj *var,
 195                               enum varobj_display_formats format);
 196
 197   /* Return non-zero if changes in value of VAR must be detected and
 198      reported by -var-update.  Return zero if -var-update should never
 199      report changes of such values.  This makes sense for structures
 200      (since the changes in children values will be reported separately),
 201      or for artificial objects (like 'public' pseudo-field in C++).
 202
 203      Return value of 0 means that gdb need not call value_fetch_lazy
 204      for the value of this variable object.  */
 205   int (*value_is_changeable_p) (const struct varobj *var);
 206
 207   /* Return nonzero if the type of VAR has mutated.
 208
 209      VAR's value is still the varobj's previous value, while NEW_VALUE
 210      is VAR's new value and NEW_TYPE is the var's new type.  NEW_VALUE
 211      may be NULL indicating that there is no value available (the varobj
 212      may be out of scope, of may be the child of a null pointer, for
 213      instance).  NEW_TYPE, on the other hand, must never be NULL.
 214
 215      This function should also be able to assume that var's number of
 216      children is set (not < 0).
 217
 218      Languages where types do not mutate can set this to NULL.  */
 219   int (*value_has_mutated) (const struct varobj *var, struct value *new_value,
 220                             struct type *new_type);
 221
 222   /* Return nonzero if VAR is a suitable path expression parent.
 223
 224      For C like languages with anonymous structures and unions an anonymous
 225      structure or union is not a suitable parent.  */
 226   int (*is_path_expr_parent) (const struct varobj *var);
 227 };
 228
 229 extern const struct lang_varobj_ops c_varobj_ops;
 230 extern const struct lang_varobj_ops cplus_varobj_ops;
 231 extern const struct lang_varobj_ops ada_varobj_ops;
 232
 233 #define default_varobj_ops c_varobj_ops
 234 /* API functions */
 235
 236 extern struct varobj *varobj_create (char *objname,
 237                                      char *expression, CORE_ADDR frame,
 238                                      enum varobj_type type);
 239
 240 extern char *varobj_gen_name (void);
 241
 242 extern struct varobj *varobj_get_handle (char *name);
 243
 244 extern char *varobj_get_objname (const struct varobj *var);
 245
 246 extern char *varobj_get_expression (const struct varobj *var);
 247
 248 /* Delete a varobj and all its children if only_children == 0, otherwise delete
 249    only the children.  Return the number of deleted variables.  */
 250
 251 extern int varobj_delete (struct varobj *var, int only_children);
 252
 253 extern enum varobj_display_formats varobj_set_display_format (
 254                                                          struct varobj *var,
 255                                         enum varobj_display_formats format);
 256
 257 extern enum varobj_display_formats varobj_get_display_format (
 258                                                 const struct varobj *var);
 259
 260 extern int varobj_get_thread_id (const struct varobj *var);
 261
 262 extern void varobj_set_frozen (struct varobj *var, int frozen);
 263
 264 extern int varobj_get_frozen (const struct varobj *var);
 265
 266 extern void varobj_get_child_range (const struct varobj *var, int *from,
 267                                     int *to);
 268
 269 extern void varobj_set_child_range (struct varobj *var, int from, int to);
 270
 271 extern char *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 char *varobj_get_type (struct varobj *var);
 287
 288 extern struct type *varobj_get_gdb_type (const struct varobj *var);
 289
 290 extern 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 char *varobj_get_formatted_value (struct varobj *var,
 298                                          enum varobj_display_formats format);
 299
 300 extern char *varobj_get_value (struct varobj *var);
 301
 302 extern int varobj_set_value (struct varobj *var, char *expression);
 303
 304 extern void all_root_varobjs (void (*func) (struct varobj *var, void *data),
 305                               void *data);
 306
 307 extern VEC(varobj_update_result) *varobj_update (struct varobj **varp,
 308                                                  int is_explicit);
 309
 310 extern void varobj_invalidate (void);
 311
 312 extern int varobj_editable_p (const struct varobj *var);
 313
 314 extern int varobj_floating_p (const struct varobj *var);
 315
 316 extern void varobj_set_visualizer (struct varobj *var,
 317                                    const char *visualizer);
 318
 319 extern void varobj_enable_pretty_printing (void);
 320
 321 extern int varobj_has_more (const struct varobj *var, int to);
 322
 323 extern int varobj_is_dynamic_p (const struct varobj *var);
 324
 325 extern struct cleanup *varobj_ensure_python_env (const struct varobj *var);
 326
 327 extern int varobj_default_value_is_changeable_p (const struct varobj *var);
 328 extern int varobj_value_is_changeable_p (const struct varobj *var);
 329
 330 extern struct type *varobj_get_value_type (const struct varobj *var);
 331
 332 extern int varobj_is_anonymous_child (const struct varobj *child);
 333
 334 extern const struct varobj *
 335   varobj_get_path_expr_parent (const struct varobj *var);
 336
 337 extern char *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 */