/**
* "When new links are added or opened, and if we're configured to add nexthop routes, try to add
* a new route for the given link." [DTN2]
*/
public void add_nexthop_route(final Link link) {
// "If we're configured to do so, create a route entry for the eid
// specified by the link when it connected, using the
// scheme-specific code to transform the URI to wildcard
// the service part" [DTN2]
EndpointID eid = link.remote_eid();
if (config_.add_nexthop_routes() && !eid.equals(EndpointID.NULL_EID())) {
EndpointIDPattern eid_pattern = new EndpointIDPattern(link.remote_eid());
// "attempt to build a route pattern from link's remote_eid" [DTN2]
if (!eid_pattern.append_service_wildcard())
// "else assign remote_eid as-is" [DTN2]
eid_pattern.assign(link.remote_eid());
RouteEntryVec ignored = new RouteEntryVec();
if (route_table_.get_matching(eid_pattern, link, ignored) == 0) {
RouteEntry entry = new RouteEntry(eid_pattern, link);
entry.set_action(ForwardingInfo.action_t.FORWARD_ACTION);
add_route(entry);
}
}
}
/** "Try to forward a bundle to a next hop route." [DTN2] */
protected boolean fwd_to_nexthop(Bundle bundle, RouteEntry route) {
Link link = route.link();
// "if the link is available and not open, open it" [DTN2]
if (link.isNotUnavailable() && (!link.isopen()) && (!link.isopening())) {
Log.d(TAG, String.format("opening %s because a message is intended for it", link.name()));
actions_.open_link(link);
}
// "if the link is open and has space in the queue, then queue the
// bundle for transmission there" [DTN2]
if (link.isopen() && !link.queue_is_full()) {
Log.d(TAG, String.format("queuing %d on %s", bundle.bundleid(), link.name()));
actions_.queue_bundle(bundle, link, route.action(), route.custody_spec());
return true;
}
// "otherwise we can't send the bundle now, so put it on the link's
// deferred list and log reason why we can't forward it" [DTN2]
DeferredList deferred = deferred_list(link);
if (!bundle.is_queued_on(deferred.list())) {
ForwardingInfo info =
new ForwardingInfo(
ForwardingInfo.state_t.NONE,
route.action(),
link.name_str(),
0xffffffff,
link.remote_eid(),
route.custody_spec());
deferred.add(bundle, info);
} else {
Log.w(
TAG,
String.format(
"bundle %d already exists on deferred list of link %s",
bundle.bundleid(), link.name()));
}
if (!link.isNotUnavailable()) {
Log.d(
TAG,
String.format(
"can't forward bundle %d to %s because link not available",
bundle.bundleid(), link.name()));
} else if (!link.isopen()) {
Log.d(
TAG,
String.format(
TAG,
"can't forward bundle %d to %s because link not open",
bundle.bundleid(),
link.name()));
} else if (link.queue_is_full()) {
Log.d(
TAG,
String.format(
TAG,
"can't forward bundle %d to %s because link queue is full",
bundle.bundleid(),
link.name()));
} else {
Log.d(TAG, String.format(TAG, "can't forward %d to %s", bundle.bundleid(), link.name()));
}
return false;
}
