Added list_is_empty function to BIRD lists.

src/common/lists.c

@@ -177,3 +177,20 @@ size_t list_size(const list *l)
 
 	return count;
 }
+
+/**
+ * list_is_empty - Checks whether the list is empty
+ * @l: list
+ *
+ * This function returns 1 if list is empty, 0 otherwise.
+ */
+int list_is_empty(const list *l)
+{
+	node *n = 0;
+	WALK_LIST(n, *l) {
+		return 0;
+	}
+
+	return 1;
+}
+

src/common/lists.h

@@ -82,6 +82,7 @@ void init_list(list *);
 void insert_node(node *, node *);
 void list_dup(list *dst, list *src, size_t itemsz);
 size_t list_size(const list *);
+int list_is_empty(const list *l);
 
 /*!
  * \brief List item for string lists.