+/* Extracts the flow stats for a packet. The 'flow' and 'packet'
+ * arguments must have been initialized through a call to flow_extract().
+ */
+void
+dpif_flow_stats_extract(const struct flow *flow, struct ofpbuf *packet,
+ struct dpif_flow_stats *stats)
+{
+ memset(stats, 0, sizeof(*stats));
+
+ if ((flow->dl_type == htons(ETH_TYPE_IP)) && packet->l4) {
+ if ((flow->nw_proto == IPPROTO_TCP) && packet->l7) {
+ struct tcp_header *tcp = packet->l4;
+ stats->tcp_flags = TCP_FLAGS(tcp->tcp_ctl);
+ }
+ }
+
+ stats->n_bytes = packet->size;
+ stats->n_packets = 1;
+}
+
+/* Appends a human-readable representation of 'stats' to 's'. */
+void
+dpif_flow_stats_format(const struct dpif_flow_stats *stats, struct ds *s)
+{
+ ds_put_format(s, "packets:%"PRIu64", bytes:%"PRIu64", used:",
+ stats->n_packets, stats->n_bytes);
+ if (stats->used) {
+ ds_put_format(s, "%.3fs", (time_msec() - stats->used) / 1000.0);
+ } else {
+ ds_put_format(s, "never");
+ }
+ /* XXX tcp_flags? */
+}
+