Match previous and current array of elements

Find out which elements were deleted/added based on 2 arrays showing
the system state before and after. It does so in linear time by using
another auxiliar list.

By: Lucas De Marchi <lucas.demarchi@profusion.mobi>

git-svn-id: svn+ssh://svn.enlightenment.org/var/svn/e/trunk/e_dbus@45871 7cbeb6ba-43b4-40fd-8cce-4c39aea84d33

diff --git a/src/lib/connman/e_connman_element.c b/src/lib/connman/e_connman_element.c
index fb330c8..db1a50a 100644 (file)
--- a/src/lib/connman/e_connman_element.c
+++ b/src/lib/connman/e_connman_element.c
@@ -490,6 +490,105 @@ _e_connman_element_objects_array_register(E_Connman_Array *array, const char *na
      _e_connman_element_item_register(name, item);
 }
 
+/* Match 2 arrays to find which are new and which are old elements
+ * For new elements, register them under prop_name property
+ * For old elements, unregister them, sending proper DEL event
+ */
+static void
+_e_connman_element_array_match(E_Connman_Array *old, E_Connman_Array *new, const char *prop_name)
+{
+   Eina_List *deleted = NULL;
+   Eina_Array_Iterator iter_old, iter_new;
+   unsigned int i_old = 0, i_new = 0;
+   void *item_old, *item_new;
+   Eina_List *l;
+   void *data;
+
+   if (!old)
+     return;
+   if (old->type != DBUS_TYPE_OBJECT_PATH)
+     return;
+
+   if ((!new) || (!new->array) || eina_array_count_get(new->array) == 0)
+     {
+       if ((!old) || (!old->array) || eina_array_count_get(old->array) == 0)
+         return;
+       else
+         {
+            iter_old = old->array->data;
+            goto out_remove_remaining;
+         }
+     }
+
+   iter_new = new->array->data;
+   item_new = *iter_new;
+   EINA_ARRAY_ITER_NEXT(old->array, i_old, item_old, iter_old)
+     {
+       if (item_old == item_new)
+         {
+            i_new++;
+            if (i_new >= eina_array_count_get(new->array))
+              {
+                 i_old++;
+                 break;
+              }
+
+            iter_new++;
+            item_new = *iter_new;
+         }
+       else
+         deleted = eina_list_append(deleted, item_old);
+     }
+
+   for(; i_new < eina_array_count_get(new->array); iter_new++, i_new++)
+     {
+       bool found = 0;
+       item_new = *iter_new;
+       if (!item_new)
+         break;
+
+       EINA_LIST_FOREACH(deleted, l, data)
+         {
+            if (data == item_new)
+              {
+                 deleted = eina_list_remove_list(deleted, l);
+                 found = 1;
+                 break;
+              }
+         }
+       if (!found)
+         {
+           _e_connman_element_item_register(prop_name, item_new);
+           DBG("Add element %s\n", (const char *) item_new);
+         }
+     }
+
+   /* everybody after i_old on old->array + everybody from deleted list
+      will be removed
+    */
+   EINA_LIST_FREE(deleted, data)
+     {
+       E_Connman_Element *e = e_connman_element_get(data);
+       if (e)
+         e_connman_element_unregister(e);
+       DBG("Delete element %s\n", (const char *) data);
+     }
+
+out_remove_remaining:
+   for(; i_old < eina_array_count_get(old->array); iter_old++, i_old++)
+     {
+       E_Connman_Element *e;
+       item_old = *iter_old;
+       if (!item_old)
+         break;
+
+       e = e_connman_element_get(item_old);
+       if (e)
+         e_connman_element_unregister(e);
+       DBG("Delete element %s\n", (const char *) item_old);
+     }
+}
+
 static bool
 _e_connman_element_property_update(E_Connman_Element_Property *property, int type, void *data)
 {
@@ -571,8 +670,8 @@ _e_connman_element_property_update(E_Connman_Element_Property *property, int typ
         if (!changed)
           if (property->value.array)
             {
+               _e_connman_element_array_match(property->value.array, data, property->name);
                _e_connman_element_array_free(property->value.array, data);
-               _e_connman_element_objects_array_register(data, property->name);
             }
         property->value.array = data;
         changed = 1;