/** ************************************************** */
void insertevent(Event p) {
Event q, qold;
if (TRACE > 3) {
myGUI.println(" INSERTEVENT: time is " + clocktime);
myGUI.println(" INSERTEVENT: future time will be " + p.evtime);
}
q = evlist; /* q points to header of list in which p struct inserted */
if (q == null) {
/* list is empty */
evlist = p;
p.next = null;
p.prev = null;
} else {
for (qold = q; q != null && p.evtime > q.evtime; q = q.next) qold = q;
if (q == null) {
/* end of list */
qold.next = p;
p.prev = qold;
p.next = null;
} else if (q == evlist) {
/* front of list */
p.next = evlist;
p.prev = null;
p.next.prev = p;
evlist = p;
} else {
/* middle of list */
p.next = q;
p.prev = q.prev;
q.prev.next = p;
q.prev = p;
}
}
}
void printevlist() {
Event q;
myGUI.println("--------------\nEvent List Follows:");
for (q = evlist; q != null; q = q.next) {
myGUI.println("Event time: " + q.evtime + ", type: " + q.evtype + " entity: " + q.eventity);
}
myGUI.println("--------------");
}
/** ************************ TOLAYER2 ************** */
void toLayer2(RouterPacket packet) {
RouterPacket mypktptr;
Event evptr, q;
double lastime;
int i;
/* be nice: check if source and destination id's are reasonable */
if (packet.sourceid < 0 || packet.sourceid > NUM_NODES - 1) {
myGUI.println("WARNING: illegal source id in your packet, ignoring packet!");
return;
}
if (packet.destid < 0 || packet.destid > NUM_NODES - 1) {
myGUI.println("WARNING: illegal dest id in your packet, ignoring packet!");
return;
}
if (packet.sourceid == packet.destid) {
myGUI.println("WARNING: source and destination id's the same, ignoring packet!");
return;
}
if (connectcosts[packet.sourceid][packet.destid] == INFINITY) {
myGUI.println("WARNING: source and destination not connected, ignoring packet!");
return;
}
/* make a copy of the packet student just gave me since may */
/* be modified after we return back */
mypktptr = (RouterPacket) packet.clone();
if (TRACE > 2) {
myGUI.print(
" TOLAYER2: source: "
+ mypktptr.sourceid
+ " dest: "
+ mypktptr.destid
+ " costs:");
for (i = 0; i < NUM_NODES; i++) myGUI.print(mypktptr.mincost[i] + " ");
myGUI.println();
}
/* create future event for arrival of packet at the other side */
evptr = new Event();
evptr.evtype = FROM_LAYER2; /* packet will pop out from layer3 */
evptr.eventity = packet.destid; /* event occurs at other entity */
evptr.rtpktptr = mypktptr; /* save ptr to my copy of packet */
/* finally, compute the arrival time of packet at the other end.
medium can not reorder, so make sure packet arrives between 1
and 10 time units after the latest arrival time of packets
currently in the medium on their way to the destination */
lastime = clocktime;
for (q = evlist; q != null; q = q.next)
if ((q.evtype == FROM_LAYER2 && q.eventity == evptr.eventity)) lastime = q.evtime;
evptr.evtime = lastime + 9 * generator.nextDouble() + 1;
if (TRACE > 2) myGUI.println(" TOLAYER2: scheduling arrival on other side");
insertevent(evptr);
}
void runSimulation() {
Event eventptr;
while (true) {
eventptr = evlist; /* get next event to simulate */
if (eventptr == null) break;
evlist = evlist.next; /* remove this event from event list */
if (evlist != null) evlist.prev = null;
if (TRACE > 1) {
myGUI.println("MAIN: rcv event, t=" + eventptr.evtime + " at " + eventptr.eventity);
if (eventptr.evtype == FROM_LAYER2) {
myGUI.print(" src:" + eventptr.rtpktptr.sourceid);
myGUI.print(", dest:" + eventptr.rtpktptr.destid);
myGUI.println(
", contents: "
+ eventptr.rtpktptr.mincost[0]
+ " "
+ eventptr.rtpktptr.mincost[1]
+ " "
+ eventptr.rtpktptr.mincost[2]
+ " "
+ eventptr.rtpktptr.mincost[3]);
}
}
clocktime = eventptr.evtime; /* update time to next event time */
if (eventptr.evtype == FROM_LAYER2) {
if (eventptr.eventity >= 0 && eventptr.eventity < NUM_NODES)
nodes[eventptr.eventity].recvUpdate(eventptr.rtpktptr);
else {
myGUI.println("Panic: unknown event entity\n");
System.exit(0);
}
} else if (eventptr.evtype == LINK_CHANGE) {
// change link costs here if implemented
nodes[eventptr.eventity].updateLinkCost(eventptr.dest, eventptr.cost);
nodes[eventptr.dest].updateLinkCost(eventptr.eventity, eventptr.cost);
} else {
myGUI.println("Panic: unknown event type\n");
System.exit(0);
}
if (TRACE > 2) for (int i = 0; i < NUM_NODES; i++) nodes[i].printDistanceTable();
}
myGUI.println("\nSimulator terminated at t=" + clocktime + ", no packets in medium\n");
}
// --------------------------------------------------
public void printDistanceTable() {
myGUI.print("Current state for router " + myID + " at time " + sim.getClocktime() + " \n\n");
myGUI.print("Distancetable: \n");
for (int i = 0; i < RouterSimulator.NUM_NODES; i++) {
myGUI.print("\t" + i);
}
myGUI.print("\n");
for (int i = 0; i < 12 * (1 + RouterSimulator.NUM_NODES); i++) {
myGUI.print("-");
}
myGUI.print("\n");
for (int i = 0; i < RouterSimulator.NUM_NODES; i++) {
if (i != myID) {
myGUI.print("" + i);
for (int j = 0; j < RouterSimulator.NUM_NODES; j++) {
myGUI.print("\t" + neighbourVectors[i][j]);
}
myGUI.print("\n");
}
}
myGUI.print("\n");
myGUI.println("Our distance vector and routes:");
myGUI.print("dst");
for (int i = 0; i < RouterSimulator.NUM_NODES; i++) {
myGUI.print("\t" + i);
}
myGUI.print("\n");
for (int i = 0; i < 12 * (1 + RouterSimulator.NUM_NODES); i++) {
myGUI.print("-");
}
myGUI.print("\n");
myGUI.print("cost");
for (int i = 0; i < RouterSimulator.NUM_NODES; i++) {
myGUI.print("\t" + costs[i]);
}
myGUI.print("\n");
myGUI.print("route");
for (int i = 0; i < RouterSimulator.NUM_NODES; i++) {
myGUI.print("\t" + routes[i]);
}
myGUI.print("\n");
myGUI.print("\n");
myGUI.print("\n");
}
