-const char* session_state_to_string(SessionState t);
-SessionState session_state_from_string(const char *s);
+int session_send_create_reply(Session *s, sd_bus_error *error);
+
+const char* session_state_to_string(SessionState t) _const_;
+SessionState session_state_from_string(const char *s) _pure_;
+
+const char* session_type_to_string(SessionType t) _const_;
+SessionType session_type_from_string(const char *s) _pure_;
+
+const char* session_class_to_string(SessionClass t) _const_;
+SessionClass session_class_from_string(const char *s) _pure_;
+
+const char *kill_who_to_string(KillWho k) _const_;
+KillWho kill_who_from_string(const char *s) _pure_;