+const char *unit_type_to_string(UnitType i);
+UnitType unit_type_from_string(const char *s);
+
+const char *unit_load_state_to_string(UnitLoadState i);
+UnitLoadState unit_load_state_from_string(const char *s);
+
+const char *unit_active_state_to_string(UnitActiveState i);
+UnitActiveState unit_active_state_from_string(const char *s);
+
+const char *unit_dependency_to_string(UnitDependency i);
+UnitDependency unit_dependency_from_string(const char *s);
+
+char *unit_dbus_path(Unit *u);
+