+ for(from = todo_tree->head; from; from = next) /* "from" is the node from which we start */
+ {
+ next = from->next;
+ n = (node_t *)from->data;
+
+ for(to = n->edge_tree->head; to; to = to->next) /* "to" is the edge connected to "from" */
+ {
+ e = (edge_t *)to->data;
+
+ if(e->from.node == n) /* "from_hc" is the halfconnection with .node == from */
+ to_hc = e->to, from_hc = e->from;
+ else
+ to_hc = e->from, from_hc = e->to;
+
+ /* Situation:
+
+ /
+ /
+ ------(n)from_hc-----to_hc
+ \
+ \
+
+ n->address is set to the to_hc.udpaddress of the edge left of n.
+ We are currently examining the edge right of n:
+
+ - If from_hc.udpaddress != n->address, then to_hc.node is probably
+ not reachable for the nodes left of n. We do as if the indirectdata
+ flag is set on edge e.
+ - If edge e provides for better reachability of to_hc.node, update
+ to_hc.node and (re)add it to the todo_tree to (re)examine the reachability
+ of nodes behind it.
+ */
+
+ indirect = n->status.indirect || e->options & OPTION_INDIRECT || ((n != myself) && sockaddrcmp(&n->address, &from_hc.udpaddress));
+
+ if(to_hc.node->status.visited && (!to_hc.node->status.indirect || indirect))
+ continue;
+
+ to_hc.node->status.visited = 1;
+ to_hc.node->status.indirect = indirect;
+ to_hc.node->nexthop = (n->nexthop == myself) ? to_hc.node : n->nexthop;
+ to_hc.node->via = indirect ? n->via : to_hc.node;
+ to_hc.node->options = e->options;
+ if(sockaddrcmp(&to_hc.node->address, &to_hc.udpaddress))
+ {
+ node = avl_unlink(node_udp_tree, to_hc.node);
+ to_hc.node->address = to_hc.udpaddress;
+ if(to_hc.node->hostname)
+ free(to_hc.node->hostname);
+ to_hc.node->hostname = sockaddr2hostname(&to_hc.udpaddress);
+ avl_insert_node(node_udp_tree, node);
+ }
+ node = avl_alloc_node();
+ node->data = to_hc.node;
+ avl_insert_before(todo_tree, from, node);
+ }
+
+ avl_delete_node(todo_tree, from);
+ }
+ }
+
+ avl_free_tree(todo_tree);
+
+ /* Check reachability status. */
+
+ for(node = node_tree->head; node; node = next)
+ {
+ next = node->next;
+ n = (node_t *)node->data;
+
+ if(n->status.visited ^ n->status.reachable)
+ {
+ n->status.reachable = !n->status.reachable;
+ if(debug_lvl >= DEBUG_TRAFFIC)
+ if(n->status.reachable)
+ syslog(LOG_DEBUG, _("Node %s (%s) became reachable"), n->name, n->hostname);
+ else
+ syslog(LOG_DEBUG, _("Node %s (%s) became unreachable"), n->name, n->hostname);
+
+ if(!n->status.reachable)
+ {
+ n->status.reachable = 0;
+ n->status.validkey = 0;
+ n->status.waitingforkey = 0;
+ n->sent_seqno = 0;
+ }
+
+ asprintf(&envp[0], "NETNAME=%s", netname?netname:"");
+ asprintf(&envp[1], "DEVICE=%s", device?device:"");
+ asprintf(&envp[2], "INTERFACE=%s", interface?interface:"");
+ asprintf(&envp[3], "NODE=%s", n->name);
+ sockaddr2str(&n->address, &address, &port);
+ asprintf(&envp[4], "REMOTEADDRESS=%s", address);
+ asprintf(&envp[5], "REMOTEPORT=%s", port);
+ envp[6] = NULL;
+
+ asprintf(&name, n->status.reachable?"hosts/%s-up":"hosts/%s-down", n->name);
+ execute_script(name, envp);
+ free(name);
+ free(address);
+ free(port);
+
+ for(i = 0; i < 7; i++)
+ free(envp[i]);
+ }