#define MAC_MAX 1024
+/* Time, in seconds, before expiring a mac_entry due to inactivity. */
+#define MAC_ENTRY_IDLE_TIME 60
+
/* A MAC learning table entry. */
struct mac_entry {
struct list hash_node; /* Element in a mac_learning 'table' list. */
tag_type tag; /* Tag for this learning entry. */
};
+int mac_entry_age(const struct mac_entry *);
+
/* MAC learning table. */
struct mac_learning {
struct list free; /* Not-in-use entries. */