rt = agent->rtable.rt_lookup(ih->daddr());
if (rt && rt->rt_flags != RTF_UP) {
// route is yet to be repaired
// I will be conservative and bring down the route
// and send route errors upstream.
/* The following assert fails, not sure why */
/* assert (rt->rt_flags == RTF_IN_REPAIR); */
//rt->rt_seqno++;
agent->rt_down(rt);
// send RERR
#ifdef DEBUG
fprintf(stderr,"Node %d: Dst - %d, failed local repair\n",index, rt->rt_dst);
#endif
}
Packet::free((Packet *)p);
}
/*
Broadcast ID Management Functions
*/
void
AODV::id_insert(nsaddr_t id, u_int32_t bid) {
BroadcastID *b = new BroadcastID(id, bid);
assert(b);
b->expire = CURRENT_TIME + BCAST_ID_SAVE;
LIST_INSERT_HEAD(&bihead, b, link);
}
/* SRD */
bool
AODV::id_lookup(nsaddr_t id, u_int32_t bid) {
BroadcastID *b = bihead.lh_first;
// Search the list for a match of source and bid
for( ; b; b = b->link.le_next) {
if ((b->src == id) && (b->id == bid))
return true;
}
return false;
}
void
AODV::id_purge() {
BroadcastID *b = bihead.lh_first;
BroadcastID *bn;
double now = CURRENT_TIME;
for(; b; b = bn) {
bn = b->link.le_next;
if(b->expire <= now) {
LIST_REMOVE(b,link);
delete b;
}
}
}
/*
Helper Functions
*/
double
AODV::PerHopTime(aodv_rt_entry *rt) {
int num_non_zero = 0, i;
double total_latency = 0.0;
if (!rt)
return ((double) NODE_TRAVERSAL_TIME );
for (i=0; i < MAX_HISTORY; i++) {
if (rt->rt_disc_latency[i] > 0.0) {
num_non_zero++;
total_latency += rt->rt_disc_latency[i];
}
}
if (num_non_zero > 0)
return(total_latency / (double) num_non_zero);
else
return((double) NODE_TRAVERSAL_TIME);
}
/*
Link Failure Management Functions
*/
static void
aodv_rt_failed_callback(Packet *p, void *arg) {
((AODV*) arg)->rt_ll_failed(p);
}
/*
* This routine is invoked when the link-layer reports a route failed.
*/
/*邻居链路down掉，处理*/
void
AODV::rt_ll_failed(Packet *p) {
struct hdr_cmn *ch = HDR_CMN(p);
struct hdr_ip *ih = HDR_IP(p);
aodv_rt_entry *rt;
nsaddr_t broken_nbr = ch->next_hop_;//记录下一跳邻居的地址
#ifndef AODV_LINK_LAYER_DETECTION
drop(p, DROP_RTR_MAC_CALLBACK);
#else
/*
* Non-data packets and Broadcast Packets can be dropped.
*/
//如果是非数据或者广播报文，则可以直接丢弃
if(! DATA_PACKET(ch->ptype()) ||
(u_int32_t) ih->daddr() == IP_BROADCAST) {
drop(p, DROP_RTR_MAC_CALLBACK);
return;
}
log_link_broke(p);
//如果不存在到达目的节点的路径，丢弃报文
if((rt = rtable.rt_lookup(ih->daddr())) == 0) {
drop(p, DROP_RTR_MAC_CALLBACK);
return;
}
log_link_del(ch->next_hop_);
#ifdef AODV_LOCAL_REPAIR
/* if the broken link is closer to the dest than source,
attempt a local repair. Otherwise, bring down the route. */