-uint32_t pktbuf_save(struct pktbuf *, struct ofpbuf *buffer, uint16_t in_port);
-int pktbuf_retrieve(struct pktbuf *, uint32_t id, struct ofpbuf **bufferp,
- uint16_t *in_port);
+uint32_t pktbuf_save(struct pktbuf *, const void *buffer, size_t buffer_size,
+ ofp_port_t in_port);
+uint32_t pktbuf_get_null(void);
+enum ofperr pktbuf_retrieve(struct pktbuf *, uint32_t id,
+ struct ofpbuf **bufferp, ofp_port_t *in_port);