[patch 4/8] Types GC [varobj_list to all_root_varobjs]

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

Hi,

this patch is completely optional and it can be dropped, just technically the
other patches depend on it.  I find the callback based iterator easier to use,
in fact there were bugs due to the current calling semantics (`floating'
lockup, memory leaks).

The new function all_root_varobjs really fully replaces varobj_list just
varobj_list gets finally dropped only in the patch 8/8.


Thanks,
Jan

gdb/
2009-05-25  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* mi/mi-cmd-var.c (mi_cmd_var_update): Remove variables var, rootlist,
	cr, nv.  Initialize CLEANUP and "changelist" uncoditionally.  Move the
	all variables handling code to ...
	(mi_cmd_var_update_iter): ... a new function.
	(struct mi_cmd_var_update): New.
	* varobj.c (varobj_list): Define the function now as static.
	(all_root_varobjs): New function.
	* varobj.h (varobj_list): Remove the declaration.
	(all_root_varobjs): New declaration.
---
 gdb/mi/mi-cmd-var.c |   96 ++++++++++++++++++++++++++++-----------------------
 gdb/varobj.c        |   20 ++++++++++-
 gdb/varobj.h        |    3 +-
 3 files changed, 74 insertions(+), 45 deletions(-)

diff --git a/gdb/mi/mi-cmd-var.c b/gdb/mi/mi-cmd-var.c
index 9de8d3d..688999c 100644
--- a/gdb/mi/mi-cmd-var.c
+++ b/gdb/mi/mi-cmd-var.c
@@ -542,15 +542,46 @@ mi_cmd_var_assign (char *command, char **argv, int argc)
   ui_out_field_string (uiout, "value", varobj_get_value (var));
 }
 
+/* Type used for parameters passing to mi_cmd_var_update_iter.  */
+
+struct mi_cmd_var_update
+  {
+    int only_floating;
+    enum print_values print_values;
+  };
+
+/* Helper for mi_cmd_var_update - update each VAR.  */
+
+static void
+mi_cmd_var_update_iter (struct varobj *var, void *data_pointer)
+{
+  struct mi_cmd_var_update *data = data_pointer;
+  int thread_id, thread_stopped;
+
+  thread_id = varobj_get_thread_id (var);
+
+  if (thread_id == -1 && is_stopped (inferior_ptid))
+    thread_stopped = 1;
+  else
+    {
+      struct thread_info *tp = find_thread_id (thread_id);
+
+      if (tp)
+	thread_stopped = is_stopped (tp->ptid);
+      else
+	thread_stopped = 1;
+    }
+
+  if (thread_stopped)
+    if (!data->only_floating || varobj_floating_p (var))
+      varobj_update_one (var, data->print_values, 0 /* implicit */);
+}
+
 void
 mi_cmd_var_update (char *command, char **argv, int argc)
 {
-  struct varobj *var;
-  struct varobj **rootlist;
-  struct varobj **cr;
   struct cleanup *cleanup;
   char *name;
-  int nv;
   enum print_values print_values;
 
   if (argc != 1 && argc != 2)
@@ -566,56 +597,35 @@ mi_cmd_var_update (char *command, char **argv, int argc)
   else
     print_values = PRINT_NO_VALUES;
 
+  if (mi_version (uiout) <= 1)
+    cleanup = make_cleanup_ui_out_tuple_begin_end (uiout, "changelist");
+  else
+    cleanup = make_cleanup_ui_out_list_begin_end (uiout, "changelist");
+
   /* Check if the parameter is a "*" which means that we want
      to update all variables */
 
   if ((*name == '*' || *name == '@') && (*(name + 1) == '\0'))
     {
-      nv = varobj_list (&rootlist);
-      cleanup = make_cleanup (xfree, rootlist);
-      if (mi_version (uiout) <= 1)
-        make_cleanup_ui_out_tuple_begin_end (uiout, "changelist");
-      else
-        make_cleanup_ui_out_list_begin_end (uiout, "changelist");
-      if (nv <= 0)
-	{
-	  do_cleanups (cleanup);
-	  return;
-	}
-      cr = rootlist;
-      while (*cr != NULL)
-	{
-	  int thread_id = varobj_get_thread_id (*cr);
-	  int thread_stopped = 0;
-	  if (thread_id == -1 && is_stopped (inferior_ptid))
-	    thread_stopped = 1;
-	  else
-	    {	      
-	      struct thread_info *tp = find_thread_id (thread_id);
-	      if (tp)
-		thread_stopped = is_stopped (tp->ptid);
-	      else
-		thread_stopped = 1;
-	    }
-	  if (thread_stopped)
-	    if (*name == '*' || varobj_floating_p (*cr))
-	      varobj_update_one (*cr, print_values, 0 /* implicit */);
-	  cr++;
-	}
-      do_cleanups (cleanup);
+      struct mi_cmd_var_update data;
+
+      data.only_floating = *name == '@';
+      data.print_values = print_values;
+
+      /* varobj_update_one automatically updates all the children of VAROBJ.
+	 Therefore update each VAROBJ only once by iterating only the root
+	 VAROBJs.  */
+
+      all_root_varobjs (mi_cmd_var_update_iter, &data);
     }
   else
     {
-      /* Get varobj handle, if a valid var obj name was specified */
-      var = varobj_get_handle (name);
+      struct varobj *var = varobj_get_handle (name);
 
-      if (mi_version (uiout) <= 1)
-        cleanup = make_cleanup_ui_out_tuple_begin_end (uiout, "changelist");
-      else
-        cleanup = make_cleanup_ui_out_list_begin_end (uiout, "changelist");
       varobj_update_one (var, print_values, 1 /* explicit */);
-      do_cleanups (cleanup);
     }
+
+  do_cleanups (cleanup);
 }
 
 /* Helper for mi_cmd_var_update().  */
diff --git a/gdb/varobj.c b/gdb/varobj.c
index e8556d7..718c690 100644
--- a/gdb/varobj.c
+++ b/gdb/varobj.c
@@ -946,7 +946,7 @@ varobj_set_value (struct varobj *var, char *expression)
 }
 
 /* Returns a malloc'ed list with all root variable objects */
-int
+static int
 varobj_list (struct varobj ***varlist)
 {
   struct varobj **cv;
@@ -2734,6 +2734,24 @@ java_value_of_variable (struct varobj *var, enum varobj_display_formats format)
 {
   return cplus_value_of_variable (var, format);
 }
+
+/* Iterate all the existing _root_ VAROBJs and call the FUNC callback for them
+   with an arbitrary caller supplied DATA pointer.  */
+
+void
+all_root_varobjs (void (*func) (struct varobj *var, void *data), void *data)
+{
+  struct varobj_root *var_root, *var_root_next;
+
+  /* Iterate "safely" - handle if the callee deletes its passed VAROBJ.  */
+
+  for (var_root = rootlist; var_root != NULL; var_root = var_root_next)
+    {
+      var_root_next = var_root->next;
+
+      (*func) (var_root->rootvar, data);
+    }
+}
 
 extern void _initialize_varobj (void);
 void
diff --git a/gdb/varobj.h b/gdb/varobj.h
index f2cdcf8..c1471d4 100644
--- a/gdb/varobj.h
+++ b/gdb/varobj.h
@@ -130,7 +130,8 @@ extern char *varobj_get_value (struct varobj *var);
 
 extern int varobj_set_value (struct varobj *var, char *expression);
 
-extern int varobj_list (struct varobj ***rootlist);
+extern void all_root_varobjs (void (*func) (struct varobj *var, void *data),
+			      void *data);
 
 extern VEC(varobj_update_result) *varobj_update (struct varobj **varp, 
 						 int explicit);
-- 
1.6.2.2