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 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   /* 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
 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.  */
 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
 225 extern const struct lang_varobj_ops c_varobj_ops;
 226 extern const struct lang_varobj_ops cplus_varobj_ops;
 227 extern const struct lang_varobj_ops ada_varobj_ops;
 228
 229 #define default_varobj_ops c_varobj_ops
 230 /* API functions */
 231
 232 extern struct varobj *varobj_create (const char *objname,
 233                                      const char *expression, CORE_ADDR frame,
 234                                      enum varobj_type type);
 235
 236 extern char *varobj_gen_name (void);
 237
 238 extern struct varobj *varobj_get_handle (const char *name);
 239
 240 extern const char *varobj_get_objname (const struct varobj *var);
 241
 242 extern 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
 247 extern int varobj_delete (struct varobj *var, int only_children);
 248
 249 extern enum varobj_display_formats varobj_set_display_format (
 250                                                          struct varobj *var,
 251                                         enum varobj_display_formats format);
 252
 253 extern enum varobj_display_formats varobj_get_display_format (
 254                                                 const struct varobj *var);
 255
 256 extern int varobj_get_thread_id (const struct varobj *var);
 257
 258 extern void varobj_set_frozen (struct varobj *var, int frozen);
 259
 260 extern int varobj_get_frozen (const struct varobj *var);
 261
 262 extern void varobj_get_child_range (const struct varobj *var, int *from,
 263                                     int *to);
 264
 265 extern void varobj_set_child_range (struct varobj *var, int from, int to);
 266
 267 extern gdb::unique_xmalloc_ptr<char>
 268      varobj_get_display_hint (const struct varobj *var);
 269
 270 extern 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.  */
 280 extern VEC (varobj_p)* varobj_list_children (struct varobj *var,
 281                                              int *from, int *to);
 282
 283 extern std::string varobj_get_type (struct varobj *var);
 284
 285 extern struct type *varobj_get_gdb_type (const struct varobj *var);
 286
 287 extern const char *varobj_get_path_expr (const struct varobj *var);
 288
 289 extern const struct language_defn *
 290   varobj_get_language (const struct varobj *var);
 291
 292 extern int varobj_get_attributes (const struct varobj *var);
 293
 294 extern std::string
 295   varobj_get_formatted_value (struct varobj *var,
 296                               enum varobj_display_formats format);
 297
 298 extern std::string varobj_get_value (struct varobj *var);
 299
 300 extern int varobj_set_value (struct varobj *var, const char *expression);
 301
 302 extern void all_root_varobjs (void (*func) (struct varobj *var, void *data),
 303                               void *data);
 304
 305 extern VEC(varobj_update_result) *varobj_update (struct varobj **varp,
 306                                                  int is_explicit);
 307
 308 extern void varobj_invalidate (void);
 309
 310 extern int varobj_editable_p (const struct varobj *var);
 311
 312 extern int varobj_floating_p (const struct varobj *var);
 313
 314 extern void varobj_set_visualizer (struct varobj *var,
 315                                    const char *visualizer);
 316
 317 extern void varobj_enable_pretty_printing (void);
 318
 319 extern int varobj_has_more (const struct varobj *var, int to);
 320
 321 extern int varobj_is_dynamic_p (const struct varobj *var);
 322
 323 extern int varobj_default_value_is_changeable_p (const struct varobj *var);
 324 extern int varobj_value_is_changeable_p (const struct varobj *var);
 325
 326 extern struct type *varobj_get_value_type (const struct varobj *var);
 327
 328 extern int varobj_is_anonymous_child (const struct varobj *child);
 329
 330 extern const struct varobj *
 331   varobj_get_path_expr_parent (const struct varobj *var);
 332
 333 extern std::string
 334   varobj_value_get_print_value (struct value *value,
 335                                 enum varobj_display_formats format,
 336                                 const struct varobj *var);
 337
 338 extern void varobj_formatted_print_options (struct value_print_options *opts,
 339                                             enum varobj_display_formats format);
 340
 341 extern void varobj_restrict_range (VEC (varobj_p) *children, int *from,
 342                                    int *to);
 343
 344 extern int varobj_default_is_path_expr_parent (const struct varobj *var);
 345
 346 #endif /* VAROBJ_H */