void (*send_bpdu)(struct ofpbuf *bpdu, int port_no,
void *aux),
void *aux);
-void stp_destroy(struct stp *);
+struct stp *stp_ref(const struct stp *);
+void stp_unref(struct stp *);
void stp_tick(struct stp *, int ms);
void stp_set_bridge_id(struct stp *, stp_identifier bridge_id);
void stp_set_bridge_priority(struct stp *, uint16_t new_priority);
const char *stp_state_name(enum stp_state);
bool stp_forward_in_state(enum stp_state);
bool stp_learn_in_state(enum stp_state);
+bool stp_listen_in_state(enum stp_state);
/* Role of an STP port. */
enum stp_role {