Use a per-neighbour unicast buffer.

This removes duplication between unicast and multicast variants of message
formatting.

babeld.c

@@ -582,6 +582,7 @@ main(int argc, char **argv)
         send_hello(ifp);
         send_wildcard_retraction(ifp);
         send_self_update(ifp);
+        send_multicast_request(ifp, NULL, 0, NULL, 0);
         flushupdates(ifp);
         flushbuf(&ifp->buf);
     }
@@ -591,6 +592,7 @@ main(int argc, char **argv)
     while(1) {
         struct timeval tv;
         fd_set readfds;
+        struct neighbour *neigh;
 
         gettime(&now);
 
@@ -608,7 +610,9 @@ main(int argc, char **argv)
             timeval_min(&tv, &ifp->update_timeout);
             timeval_min(&tv, &ifp->update_flush_timeout);
         }
-        timeval_min(&tv, &unicast_flush_timeout);
+        FOR_ALL_NEIGHBOURS(neigh) {
+            timeval_min(&tv, &neigh->buf.timeout);
+        }
         FD_ZERO(&readfds);
         if(timeval_compare(&tv, &now) > 0) {
             int maxfd = 0;
@@ -770,11 +774,6 @@ main(int argc, char **argv)
                 do_resend();
         }
 
-        if(unicast_flush_timeout.tv_sec != 0) {
-            if(timeval_compare(&now, &unicast_flush_timeout) >= 0)
-                flush_unicast(1);
-        }
-
         FOR_ALL_INTERFACES(ifp) {
             if(!if_up(ifp))
                 continue;
@@ -786,6 +785,14 @@ main(int argc, char **argv)
             }
         }
 
+        FOR_ALL_NEIGHBOURS(neigh) {
+            if(neigh->buf.timeout.tv_sec != 0) {
+                if(timeval_compare(&now, &neigh->buf.timeout) >= 0) {
+                    flushbuf(&neigh->buf);
+                }
+            }
+        }
+
         if(UNLIKELY(debug || dumping)) {
             dump_tables(stdout);
             dumping = 0;

interface.c

@@ -480,6 +480,7 @@ interface_up(struct interface *ifp, int up)
         send_hello(ifp);
         if(rc > 0)
             send_update(ifp, 0, NULL, 0, NULL, 0);
+        send_multicast_request(ifp, NULL, 0, NULL, 0);
     } else {
         flush_interface_routes(ifp, 0);
         ifp->buf.len = 0;
@@ -566,6 +567,7 @@ check_interfaces(void)
             check_interface_channel(ifp);
             rc = check_interface_ipv4(ifp);
             if(rc > 0) {
+                send_multicast_request(ifp, NULL, 0, NULL, 0);
                 send_update(ifp, 0, NULL, 0, NULL, 0);
             }
         }

message.h

@@ -52,9 +52,6 @@ extern int split_horizon;
 
 extern unsigned char packet_header[4];
 
-extern struct neighbour *unicast_neighbour;
-extern struct timeval unicast_flush_timeout;
-
 void parse_packet(const unsigned char *from, struct interface *ifp,
                   const unsigned char *packet, int packetlen);
 void flushbuf(struct buffered *buf);
@@ -76,14 +73,15 @@ void update_myseqno(void);
 void send_self_update(struct interface *ifp);
 void send_ihu(struct neighbour *neigh, struct interface *ifp);
 void send_marginal_ihu(struct interface *ifp);
-void send_request(struct interface *ifp,
+void send_multicast_request(struct interface *ifp,
                   const unsigned char *prefix, unsigned char plen,
                   const unsigned char *src_prefix, unsigned char src_plen);
 void send_unicast_request(struct neighbour *neigh,
                           const unsigned char *prefix, unsigned char plen,
                           const unsigned char *src_prefix,
                           unsigned char src_plen);
-void send_multihop_request(struct interface *ifp,
+void
+send_multicast_multihop_request(struct interface *ifp,
                                 const unsigned char *prefix, unsigned char plen,
                                 const unsigned char *src_prefix,
                                 unsigned char src_plen,

neighbour.c

@@ -57,8 +57,6 @@ void
 flush_neighbour(struct neighbour *neigh)
 {
     flush_neighbour_routes(neigh);
-    if(unicast_neighbour == neigh)
-        flush_unicast(1);
     flush_resends(neigh);
 
     if(neighs == neigh) {
@@ -70,6 +68,7 @@ flush_neighbour(struct neighbour *neigh)
         previous->next = neigh->next;
     }
     local_notify_neighbour(neigh, LOCAL_FLUSH);
+    free(neigh->buf.buf);
     free(neigh);
 }
 
@@ -78,6 +77,7 @@ find_neighbour(const unsigned char *address, struct interface *ifp)
 {
     struct neighbour *neigh;
     const struct timeval zero = {0, 0};
+    char *buf;
 
     neigh = find_neighbour_nocreate(address, ifp);
     if(neigh)
@@ -86,6 +86,12 @@ find_neighbour(const unsigned char *address, struct interface *ifp)
     debugf("Creating neighbour %s on %s.\n",
            format_address(address), ifp->name);
 
+    buf = malloc(ifp->buf.size);
+    if(buf == NULL) {
+        perror("malloc(neighbour->buf)");
+        return NULL;
+    }
+
     neigh = calloc(1, sizeof(struct neighbour));
     if(neigh == NULL) {
         perror("malloc(neighbour)");
@@ -100,6 +106,13 @@ find_neighbour(const unsigned char *address, struct interface *ifp)
     neigh->hello_rtt_receive_time = zero;
     neigh->rtt_time = zero;
     neigh->ifp = ifp;
+    neigh->buf.buf = buf;
+    neigh->buf.size = ifp->buf.size;
+    neigh->buf.flush_interval = ifp->buf.flush_interval;
+    neigh->buf.sin6.sin6_family = AF_INET6;
+    memcpy(&neigh->buf.sin6.sin6_addr, address, 16);
+    neigh->buf.sin6.sin6_port = htons(protocol_port);
+    neigh->buf.sin6.sin6_scope_id = ifp->ifindex;
     neigh->next = neighs;
     neighs = neigh;
     local_notify_neighbour(neigh, LOCAL_ADD);

neighbour.h

@@ -44,6 +44,7 @@ struct neighbour {
     unsigned int rtt;
     struct timeval rtt_time;
     struct interface *ifp;
+    struct buffered buf;
 };
 
 extern struct neighbour *neighs;

resend.c

@@ -306,10 +306,12 @@ do_resend()
             if(timeval_compare(&now, &timeout) >= 0) {
                 switch(resend->kind) {
                 case RESEND_REQUEST:
-                    send_multihop_request(resend->ifp,
+                    send_multicast_multihop_request(resend->ifp,
                                                     resend->prefix, resend->plen,
-                                          resend->src_prefix, resend->src_plen,
-                                          resend->seqno, resend->id, 127);
+                                                    resend->src_prefix,
+                                                    resend->src_plen,
+                                                    resend->seqno, resend->id,
+                                                    127);
                     break;
                 case RESEND_UPDATE:
                     send_update(resend->ifp, 1,

route.c

@@ -1139,7 +1139,7 @@ send_triggered_update(struct babel_route *route, struct source *oldsrc,
 
     if(oldmetric < INFINITY) {
         if(newmetric >= oldmetric + 288) {
-            send_request(NULL, route->src->prefix, route->src->plen,
+            send_multicast_request(NULL, route->src->prefix, route->src->plen,
                                    route->src->src_prefix, route->src->src_plen);
         }
     }