Basic c++ification of varobj

This patch does a basic c++ification or the varobj data structure.

  - varobj: add constructor and destructor, initialize fields
  - varobj_root: initialize fields
  - varobj_dynamic: initialize fields

This allows getting rid of new_variable, new_root_variable.
free_variable essentially becomes varobj's destructor.  This also allows
getting rid of a cleanup, make_cleanup_free_variable, which was only
used in varobj_create in case the varobj creation fails.  It is replaced
with a unique_ptr.

gdb/ChangeLog:

	* varobj.h (struct varobj): Add constructor and destructor,
	initialize fields.
	* varobj.c (struct varobj_root): Initialize fields.
	(struct varobj_dynamic): Initialize fields.
	(varobj_create): Use unique_ptr instead of cleanup.  Create
	varobj with new instead of new_root_variable.
	(delete_variable_1): Free variable with delete instead of
	free_variable.
	(create_child_with_value): Create variable with new instead of
	new_variable.
	(varobj::varobj): New.
	(varobj::~varobj): New (body mostly coming from free_variable).
	(new_variable): Remove.
	(free_variable): Remove.
	(do_free_variable_cleanup): Remove.
	(make_cleanup_free_variable): Remove.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 9121ff2..5dccc13 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,22 @@
+2017-11-22  Simon Marchi  <simon.marchi@polymtl.ca>
+
+       * varobj.h (struct varobj): Add constructor and destructor,
+       initialize fields.
+       * varobj.c (struct varobj_root): Initialize fields.
+       (struct varobj_dynamic): Initialize fields.
+       (varobj_create): Use unique_ptr instead of cleanup.  Create
+       varobj with new instead of new_root_variable.
+       (delete_variable_1): Free variable with delete instead of
+       free_variable.
+       (create_child_with_value): Create variable with new instead of
+       new_variable.
+       (varobj::varobj): New.
+       (varobj::~varobj): New (body mostly coming from free_variable).
+       (new_variable): Remove.
+       (free_variable): Remove.
+       (do_free_variable_cleanup): Remove.
+       (make_cleanup_free_variable): Remove.
+

 2017-11-22  Ulrich Weigand  <uweigand@de.ibm.com>
 
        * core-regset.c: Remove file.
 2017-11-22  Ulrich Weigand  <uweigand@de.ibm.com>
 
        * core-regset.c: Remove file.

diff --git a/gdb/varobj.c b/gdb/varobj.c
index 2d850fb..2bc7fcd 100644 (file)
--- a/gdb/varobj.c
+++ b/gdb/varobj.c
@@ -68,42 +68,41 @@ varobj_enable_pretty_printing (void)
    varobj.  */
 struct varobj_root
 {
    varobj.  */
 struct varobj_root
 {

-

   /* The expression for this parent.  */
   expression_up exp;
 
   /* Block for which this expression is valid.  */
   /* The expression for this parent.  */
   expression_up exp;
 
   /* Block for which this expression is valid.  */

-  const struct block *valid_block;
+  const struct block *valid_block = NULL;

 
   /* The frame for this expression.  This field is set iff valid_block is
      not NULL.  */
 
   /* The frame for this expression.  This field is set iff valid_block is
      not NULL.  */

-  struct frame_id frame;
+  struct frame_id frame = null_frame_id;

 
   /* The global thread ID that this varobj_root belongs to.  This field
      is only valid if valid_block is not NULL.
      When not 0, indicates which thread 'frame' belongs to.
      When 0, indicates that the thread list was empty when the varobj_root
      was created.  */
 
   /* The global thread ID that this varobj_root belongs to.  This field
      is only valid if valid_block is not NULL.
      When not 0, indicates which thread 'frame' belongs to.
      When 0, indicates that the thread list was empty when the varobj_root
      was created.  */

-  int thread_id;
+  int thread_id = 0;

 
   /* If 1, the -var-update always recomputes the value in the
      current thread and frame.  Otherwise, variable object is
      always updated in the specific scope/thread/frame.  */
 
   /* If 1, the -var-update always recomputes the value in the
      current thread and frame.  Otherwise, variable object is
      always updated in the specific scope/thread/frame.  */

-  int floating;
+  int floating = 0;

 
   /* Flag that indicates validity: set to 0 when this varobj_root refers 
      to symbols that do not exist anymore.  */
 
   /* Flag that indicates validity: set to 0 when this varobj_root refers 
      to symbols that do not exist anymore.  */

-  int is_valid;
+  int is_valid = 1;

 
   /* Language-related operations for this variable and its
      children.  */
 
   /* Language-related operations for this variable and its
      children.  */

-  const struct lang_varobj_ops *lang_ops;
+  const struct lang_varobj_ops *lang_ops = NULL;

 
   /* The varobj for this root node.  */
 
   /* The varobj for this root node.  */

-  struct varobj *rootvar;
+  struct varobj *rootvar = NULL;

 
   /* Next root variable */
 
   /* Next root variable */

-  struct varobj_root *next;
+  struct varobj_root *next = NULL;

 };
 
 /* Dynamic part of varobj.  */
 };
 
 /* Dynamic part of varobj.  */


@@ -114,27 +113,27 @@ struct varobj_dynamic
      used to decide if dynamic varobj should recompute their children.
      In the event that the frontend never asked for the children, we
      can avoid that.  */
      used to decide if dynamic varobj should recompute their children.
      In the event that the frontend never asked for the children, we
      can avoid that.  */

-  int children_requested;
+  int children_requested = 0;

 
   /* The pretty-printer constructor.  If NULL, then the default
      pretty-printer will be looked up.  If None, then no
      pretty-printer will be installed.  */
 
   /* The pretty-printer constructor.  If NULL, then the default
      pretty-printer will be looked up.  If None, then no
      pretty-printer will be installed.  */

-  PyObject *constructor;
+  PyObject *constructor = NULL;

 
   /* The pretty-printer that has been constructed.  If NULL, then a
      new printer object is needed, and one will be constructed.  */
 
   /* The pretty-printer that has been constructed.  If NULL, then a
      new printer object is needed, and one will be constructed.  */

-  PyObject *pretty_printer;
+  PyObject *pretty_printer = NULL;

 
   /* The iterator returned by the printer's 'children' method, or NULL
      if not available.  */
 
   /* The iterator returned by the printer's 'children' method, or NULL
      if not available.  */

-  struct varobj_iter *child_iter;
+  struct varobj_iter *child_iter = NULL;

 
   /* We request one extra item from the iterator, so that we can
      report to the caller whether there are more items than we have
      already reported.  However, we don't want to install this value
      when we read it, because that will mess up future updates.  So,
      we stash it here instead.  */
 
   /* We request one extra item from the iterator, so that we can
      report to the caller whether there are more items than we have
      already reported.  However, we don't want to install this value
      when we read it, because that will mess up future updates.  So,
      we stash it here instead.  */

-  varobj_item *saved_item;
+  varobj_item *saved_item = NULL;

 };
 
 /* A list of varobjs */
 };
 
 /* A list of varobjs */


@@ -165,14 +164,6 @@ create_child_with_value (struct varobj *parent, int index,
 
 /* Utility routines */
 
 
 /* Utility routines */
 

-static struct varobj *new_variable (void);
-
-static struct varobj *new_root_variable (void);
-
-static void free_variable (struct varobj *var);
-
-static struct cleanup *make_cleanup_free_variable (struct varobj *var);
-

 static enum varobj_display_formats variable_default_display (struct varobj *);
 
 static int update_type_if_necessary (struct varobj *var,
 static enum varobj_display_formats variable_default_display (struct varobj *);
 
 static int update_type_if_necessary (struct varobj *var,


@@ -273,12 +264,8 @@ struct varobj *
 varobj_create (const char *objname,
               const char *expression, CORE_ADDR frame, enum varobj_type type)
 {
 varobj_create (const char *objname,
               const char *expression, CORE_ADDR frame, enum varobj_type type)
 {

-  struct varobj *var;
-  struct cleanup *old_chain;
-

   /* Fill out a varobj structure for the (root) variable being constructed.  */
   /* Fill out a varobj structure for the (root) variable being constructed.  */

-  var = new_root_variable ();
-  old_chain = make_cleanup_free_variable (var);
+  std::unique_ptr<varobj> var (new varobj (new varobj_root));

 
   if (expression != NULL)
     {
 
   if (expression != NULL)
     {


@@ -333,7 +320,6 @@ varobj_create (const char *objname,
 
       CATCH (except, RETURN_MASK_ERROR)
        {
 
       CATCH (except, RETURN_MASK_ERROR)
        {

-         do_cleanups (old_chain);

          return NULL;
        }
       END_CATCH
          return NULL;
        }
       END_CATCH


@@ -343,13 +329,12 @@ varobj_create (const char *objname,
          || var->root->exp->elts[0].opcode == OP_TYPEOF
          || var->root->exp->elts[0].opcode == OP_DECLTYPE)
        {
          || var->root->exp->elts[0].opcode == OP_TYPEOF
          || var->root->exp->elts[0].opcode == OP_DECLTYPE)
        {

-         do_cleanups (old_chain);

          fprintf_unfiltered (gdb_stderr, "Attempt to use a type name"
                              " as an expression.\n");
          return NULL;
        }
 
          fprintf_unfiltered (gdb_stderr, "Attempt to use a type name"
                              " as an expression.\n");
          return NULL;
        }
 

-      var->format = variable_default_display (var);
+      var->format = variable_default_display (var.get ());

       var->root->valid_block = innermost_block;
       var->name = expression;
       /* For a root var, the name and the expr are the same.  */
       var->root->valid_block = innermost_block;
       var->name = expression;
       /* For a root var, the name and the expr are the same.  */


@@ -403,10 +388,10 @@ varobj_create (const char *objname,
       /* Set language info */
       var->root->lang_ops = var->root->exp->language_defn->la_varobj_ops;
 
       /* Set language info */
       var->root->lang_ops = var->root->exp->language_defn->la_varobj_ops;
 

-      install_new_value (var, value, 1 /* Initial assignment */);
+      install_new_value (var.get (), value, 1 /* Initial assignment */);

 
       /* Set ourselves as our root.  */
 
       /* Set ourselves as our root.  */

-      var->root->rootvar = var;
+      var->root->rootvar = var.get ();

 
       /* Reset the selected frame.  */
       if (frame_id_p (old_id))
 
       /* Reset the selected frame.  */
       if (frame_id_p (old_id))


@@ -422,15 +407,11 @@ varobj_create (const char *objname,
 
       /* If a varobj name is duplicated, the install will fail so
          we must cleanup.  */
 
       /* If a varobj name is duplicated, the install will fail so
          we must cleanup.  */

-      if (!install_variable (var))
-       {
-         do_cleanups (old_chain);
-         return NULL;
-       }
+      if (!install_variable (var.get ()))
+       return NULL;

     }
 
     }
 

-  discard_cleanups (old_chain);
-  return var;
+  return var.release ();

 }
 
 /* Generates an unique name that can be used for a varobj.  */
 }
 
 /* Generates an unique name that can be used for a varobj.  */


@@ -1846,7 +1827,7 @@ delete_variable_1 (int *delcountp, struct varobj *var, int only_children_p,
     uninstall_variable (var);
 
   /* Free memory associated with this variable.  */
     uninstall_variable (var);
 
   /* Free memory associated with this variable.  */

-  free_variable (var);
+  delete var;

 }
 
 /* Install the given variable VAR with the object name VAR->OBJ_NAME.  */
 }
 
 /* Install the given variable VAR with the object name VAR->OBJ_NAME.  */


@@ -1985,15 +1966,12 @@ static struct varobj *
 create_child_with_value (struct varobj *parent, int index,
                         struct varobj_item *item)
 {
 create_child_with_value (struct varobj *parent, int index,
                         struct varobj_item *item)
 {

-  struct varobj *child;
-
-  child = new_variable ();
+  varobj *child = new varobj (parent->root);

 
   /* NAME is allocated by caller.  */
   std::swap (child->name, item->name);
   child->index = index;
   child->parent = parent;
 
   /* NAME is allocated by caller.  */
   std::swap (child->name, item->name);
   child->index = index;
   child->parent = parent;

-  child->root = parent->root;

 
   if (varobj_is_anonymous_child (child))
     child->obj_name = string_printf ("%s.%d_anonymous",
 
   if (varobj_is_anonymous_child (child))
     child->obj_name = string_printf ("%s.%d_anonymous",


@@ -2026,57 +2004,17 @@ create_child_with_value (struct varobj *parent, int index,
  */
 
 /* Allocate memory and initialize a new variable.  */
  */
 
 /* Allocate memory and initialize a new variable.  */

-static struct varobj *
-new_variable (void)
+varobj::varobj (varobj_root *root_)
+: root (root_), dynamic (new varobj_dynamic)

 {
 {

-  struct varobj *var;
-
-  var = new varobj ();
-  var->index = -1;
-  var->type = NULL;
-  var->value = NULL;
-  var->num_children = -1;
-  var->parent = NULL;
-  var->children = NULL;
-  var->format = FORMAT_NATURAL;
-  var->root = NULL;
-  var->updated = 0;
-  var->frozen = 0;
-  var->not_fetched = 0;
-  var->dynamic = XNEW (struct varobj_dynamic);
-  var->dynamic->children_requested = 0;
-  var->from = -1;
-  var->to = -1;
-  var->dynamic->constructor = 0;
-  var->dynamic->pretty_printer = 0;
-  var->dynamic->child_iter = 0;
-  var->dynamic->saved_item = 0;
-
-  return var;
-}
-
-/* Allocate memory and initialize a new root variable.  */
-static struct varobj *
-new_root_variable (void)
-{
-  struct varobj *var = new_variable ();
-
-  var->root = new varobj_root ();
-  var->root->lang_ops = NULL;
-  var->root->exp = NULL;
-  var->root->valid_block = NULL;
-  var->root->frame = null_frame_id;
-  var->root->floating = 0;
-  var->root->rootvar = NULL;
-  var->root->is_valid = 1;
-
-  return var;

 }
 
 /* Free any allocated memory associated with VAR.  */
 }
 
 /* Free any allocated memory associated with VAR.  */

-static void
-free_variable (struct varobj *var)
+
+varobj::~varobj ()

 {
 {

+  varobj *var = this;
+

 #if HAVE_PYTHON
   if (var->dynamic->pretty_printer != NULL)
     {
 #if HAVE_PYTHON
   if (var->dynamic->pretty_printer != NULL)
     {


@@ -2094,20 +2032,7 @@ free_variable (struct varobj *var)
   if (is_root_p (var))
     delete var->root;
 
   if (is_root_p (var))
     delete var->root;
 

-  xfree (var->dynamic);
-  delete var;
-}
-
-static void
-do_free_variable_cleanup (void *var)
-{
-  free_variable ((struct varobj *) var);
-}
-
-static struct cleanup *
-make_cleanup_free_variable (struct varobj *var)
-{
-  return make_cleanup (do_free_variable_cleanup, var);
+  delete var->dynamic;

 }
 
 /* Return the type of the value that's stored in VAR,
 }
 
 /* Return the type of the value that's stored in VAR,

diff --git a/gdb/varobj.h b/gdb/varobj.h
index 0d4a537..bdf748f 100644 (file)
--- a/gdb/varobj.h
+++ b/gdb/varobj.h
@@ -89,6 +89,9 @@ struct varobj_dynamic;
    a particular object variable.  */
 struct varobj
 {
    a particular object variable.  */
 struct varobj
 {

+  explicit varobj (varobj_root *root_);
+  ~varobj ();
+

   /* Name of the variable for this object.  If this variable is a
      child, then this name will be the child's source name.
      (bar, not foo.bar).  */
   /* Name of the variable for this object.  If this variable is a
      child, then this name will be the child's source name.
      (bar, not foo.bar).  */


@@ -104,37 +107,37 @@ struct varobj
   std::string obj_name;
 
   /* Index of this variable in its parent or -1.  */
   std::string obj_name;
 
   /* Index of this variable in its parent or -1.  */

-  int index;
+  int index = -1;

 
   /* The type of this variable.  This can be NULL
      for artificial variable objects -- currently, the "accessibility"
      variable objects in C++.  */
 
   /* The type of this variable.  This can be NULL
      for artificial variable objects -- currently, the "accessibility"
      variable objects in C++.  */

-  struct type *type;
+  struct type *type = NULL;

 
   /* The value of this expression or subexpression.  A NULL value
      indicates there was an error getting this value.
      Invariant: if varobj_value_is_changeable_p (this) is non-zero, 
      the value is either NULL, or not lazy.  */
 
   /* The value of this expression or subexpression.  A NULL value
      indicates there was an error getting this value.
      Invariant: if varobj_value_is_changeable_p (this) is non-zero, 
      the value is either NULL, or not lazy.  */

-  struct value *value;
+  struct value *value = NULL;

 
   /* The number of (immediate) children this variable has.  */
 
   /* The number of (immediate) children this variable has.  */

-  int num_children;
+  int num_children = -1;

 
   /* If this object is a child, this points to its immediate parent.  */
 
   /* If this object is a child, this points to its immediate parent.  */

-  const struct varobj *parent;
+  const struct varobj *parent = NULL;

 
   /* Children of this object.  */
 
   /* Children of this object.  */

-  VEC (varobj_p) *children;
+  VEC (varobj_p) *children = NULL;

 
   /* Description of the root variable.  Points to root variable for
      children.  */
   struct varobj_root *root;
 
   /* The format of the output for this object.  */
 
   /* Description of the root variable.  Points to root variable for
      children.  */
   struct varobj_root *root;
 
   /* The format of the output for this object.  */

-  enum varobj_display_formats format;
+  enum varobj_display_formats format = FORMAT_NATURAL;

 
   /* Was this variable updated via a varobj_set_value operation.  */
 
   /* Was this variable updated via a varobj_set_value operation.  */

-  int updated;
+  int updated = 0;

 
   /* Last print value.  */
   std::string print_value;
 
   /* Last print value.  */
   std::string print_value;


@@ -142,18 +145,18 @@ struct varobj
   /* Is this variable frozen.  Frozen variables are never implicitly
      updated by -var-update * 
      or -var-update <direct-or-indirect-parent>.  */
   /* Is this variable frozen.  Frozen variables are never implicitly
      updated by -var-update * 
      or -var-update <direct-or-indirect-parent>.  */

-  int frozen;
+  int frozen = 0;

 
   /* Is the value of this variable intentionally not fetched?  It is
      not fetched if either the variable is frozen, or any parents is
      frozen.  */
 
   /* Is the value of this variable intentionally not fetched?  It is
      not fetched if either the variable is frozen, or any parents is
      frozen.  */

-  int not_fetched;
+  int not_fetched = 0;

 
   /* Sub-range of children which the MI consumer has requested.  If
      FROM < 0 or TO < 0, means that all children have been
      requested.  */
 
   /* Sub-range of children which the MI consumer has requested.  If
      FROM < 0 or TO < 0, means that all children have been
      requested.  */

-  int from;
-  int to;
+  int from = -1;
+  int to = -1;

 
   /* Dynamic part of varobj.  */
   struct varobj_dynamic *dynamic;
 
   /* Dynamic part of varobj.  */
   struct varobj_dynamic *dynamic;