Add cost computation

1 files changed, 16 insertions, 3 deletions

diff --git a/ffd/ffd.c b/ffd/ffd.c
index 807a59a..b1668b0 100644
--- a/ffd/ffd.c
+++ b/ffd/ffd.c
@@ -47,7 +47,7 @@
 
 static const eth_addr_t ffd_addr = {{0x03, 0x00, 0x00, 0x00, 0x0f, 0xfd}};
 
-#define HELLO_INTERVAL 1000
+#define HELLO_INTERVAL 400
 #define IHU_INTERVAL (3*HELLO_INTERVAL)
 #define PACKET_MAX 1000
 
@@ -199,6 +199,19 @@ static uint16_t get_neigh_rxcost(const ffd_neigh_t *neigh) {
 		return (0x1000/received);
 }
 
+static uint16_t get_neigh_cost(const ffd_neigh_t *neigh) {
+	uint16_t txcost = neigh->txcost;
+	if (txcost < 256)
+		txcost = 256;
+
+	uint32_t cost = (txcost * get_neigh_rxcost(neigh)) >> 8;
+
+	if (cost > 0xffff)
+		return 0xffff;
+	else
+		return cost;
+}
+
 static void update_netifs() {
 	ffd_iface_t *iface, **cur;
 
@@ -339,7 +352,7 @@ static void handle_tlv_hello(const ffd_tlv_hello_t *tlv_hello, size_t len, const
 	neigh->last_seqno = seqno;
 	neigh->last_hello = now;
 
-	fprintf(stderr, "debug: accepted hello, log %04x, rxcost is %u now.\n", neigh->hello_log, get_neigh_rxcost(neigh));
+	fprintf(stderr, "debug: accepted hello, log %04x, rxcost is %u, cost is %u now.\n", neigh->hello_log, get_neigh_rxcost(neigh), get_neigh_cost(neigh));
 }
 
 static void handle_tlv_ihu(const ffd_tlv_ihu_t *tlv_ihu, size_t len, const eth_addr_t *addr, ffd_iface_t *iface) {
@@ -365,7 +378,7 @@ static void handle_tlv_ihu(const ffd_tlv_ihu_t *tlv_ihu, size_t len, const eth_a
 	neigh->last_ihu = now;
 	neigh->txcost = ntohs(tlv_ihu->rxcost);
 
-	fprintf(stderr, "debug: accepted IHU, txcost is %u now.\n", neigh->txcost);
+	fprintf(stderr, "debug: accepted IHU, txcost is %u, cost is %u now.\n", neigh->txcost, get_neigh_cost(neigh));
 }
 
 static void handle_tlv(ffd_tlv_type_t type, const void *data, size_t len, void *arg) {