Added an insert_after and insert_before function to linked_list_t.

src/libstrongswan/utils/linked_list.c

@@ -145,20 +145,16 @@ METHOD(enumerator_t, enumerate, bool,
 {
 	if (!this->current)
 	{
-		if (!this->list->first)
-		{
-			return FALSE;
-		}
 		this->current = this->list->first;
 	}
 	else
 	{
-		if (!this->current->next)
-		{
-			return FALSE;
-		}
 		this->current = this->current->next;
 	}
+	if (!this->current)
+	{
+		return FALSE;
+	}
 	*item = this->current->value;
 	return TRUE;
 }
@@ -270,30 +266,60 @@ METHOD(iterator_t, iterator_remove, status_t,
 	return SUCCESS;
 }
 
-METHOD(iterator_t, iterator_insert_before, void,
+static void insert_item_before(private_linked_list_t *this, element_t *current,
-	   private_iterator_t * iterator, void *item)
+							   void *item)
 {
-	if (iterator->current == NULL)
+	if (!current)
 	{
-		iterator->list->public.insert_first(&(iterator->list->public), item);
+		this->public.insert_last(&this->public, item);
 		return;
 	}
-
 	element_t *element = element_create(item);
-	if (iterator->current->previous == NULL)
+	if (current->previous)
 	{
-		iterator->current->previous = element;
+		current->previous->next = element;
-		element->next = iterator->current;
+		element->previous = current->previous;
-		iterator->list->first = element;
+		current->previous = element;
+		element->next = current;
 	}
 	else
 	{
-		iterator->current->previous->next = element;
+		current->previous = element;
-		element->previous = iterator->current->previous;
+		element->next = current;
-		iterator->current->previous = element;
+		this->first = element;
-		element->next = iterator->current;
 	}
-	iterator->list->count++;
+	this->count++;
+}
+
+static void insert_item_after(private_linked_list_t *this, element_t *current,
+							  void *item)
+{
+	if (!current)
+	{
+		this->public.insert_last(&this->public, item);
+		return;
+	}
+	element_t *element = element_create(item);
+	if (current->next)
+	{
+		current->next->previous = element;
+		element->next = current->next;
+		current->next = element;
+		element->previous = current;
+	}
+	else
+	{
+		current->next = element;
+		element->previous = current;
+		this->last = element;
+	}
+	this->count++;
+}
+
+METHOD(iterator_t, iterator_insert_before, void,
+	   private_iterator_t * iterator, void *item)
+{
+	insert_item_before(iterator->list, iterator->current, item);
 }
 
 METHOD(iterator_t, iterator_replace, status_t,
@@ -315,27 +341,7 @@ METHOD(iterator_t, iterator_replace, status_t,
 METHOD(iterator_t, iterator_insert_after, void,
 	   private_iterator_t *iterator, void *item)
 {
-	if (iterator->current == NULL)
+	insert_item_after(iterator->list, iterator->current, item);
-	{
-		iterator->list->public.insert_first(&(iterator->list->public),item);
-		return;
-	}
-
-	element_t *element = element_create(item);
-	if (iterator->current->next == NULL)
-	{
-		iterator->current->next = element;
-		element->previous = iterator->current;
-		iterator->list->last = element;
-	}
-	else
-	{
-		iterator->current->next->previous = element;
-		element->next = iterator->current->next;
-		iterator->current->next = element;
-		element->previous = iterator->current;
-	}
-	iterator->list->count++;
 }
 
 METHOD(iterator_t, iterator_destroy, void,
@@ -456,6 +462,20 @@ METHOD(linked_list_t, insert_last, void,
 	this->count++;
 }
 
+METHOD(linked_list_t, insert_before, void,
+	   private_linked_list_t *this, private_enumerator_t *enumerator,
+	   void *item)
+{
+	insert_item_before(this, enumerator->current, item);
+}
+
+METHOD(linked_list_t, insert_after, void,
+	   private_linked_list_t *this, private_enumerator_t *enumerator,
+	   void *item)
+{
+	insert_item_after(this, enumerator->current, item);
+}
+
 METHOD(linked_list_t, get_last, status_t,
 	   private_linked_list_t *this, void **item)
 {
@@ -700,6 +720,8 @@ linked_list_t *linked_list_create()
 			.find_last = (void*)_find_last,
 			.insert_first = _insert_first,
 			.insert_last = _insert_last,
+			.insert_after = (void*)_insert_after,
+			.insert_before = (void*)_insert_before,
 			.remove_first = _remove_first,
 			.remove_last = _remove_last,
 			.remove = _remove_,

src/libstrongswan/utils/linked_list.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2007-2008 Tobias Brunner
+ * Copyright (C) 2007-2011 Tobias Brunner
  * Copyright (C) 2005-2008 Martin Willi
  * Copyright (C) 2005 Jan Hutter
  * Hochschule fuer Technik Rapperswil
@@ -99,6 +99,32 @@ struct linked_list_t {
 	 */
 	status_t (*remove_first) (linked_list_t *this, void **item);
 
+	/**
+	 * Inserts a new item before the item the enumerator currently points to.
+	 *
+	 * @note The position of the enumerator is not changed.
+	 * @note If the enumerator's position is invalid, the item is inserted last.
+	 *
+	 * @param enumerator	enumerator with position
+	 * @param item			item value to insert in list
+	 */
+	void (*insert_before)(linked_list_t *this, enumerator_t *enumerator,
+						  void *item);
+
+	/**
+	 * Inserts a new item after the item the enumerator currently points to.
+	 *
+	 * @note The position of the enumerator is not changed (thus the next item
+	 * the enumerator returns will be the inserted item).
+	 *
+	 * @note If the enumerator's position is invalid, the item is inserted last.
+	 *
+	 * @param enumerator	enumerator with position
+	 * @param item			item value to insert in list
+	 */
+	void (*insert_after)(linked_list_t *this, enumerator_t *enumerator,
+						 void *item);
+
 	/**
 	 * Remove an item from the list where the enumerator points to.
 	 *