/// <summary>
/// Clones this instance.
/// </summary>
/// <returns>The cloned instance.</returns>
public override object Clone()
{
var clone = new DsrRouteRequestMessage()
{
RequestId = this.RequestId,
Nodes = new List <string>(this.Nodes)
};
return(this.CopyTo(clone));
}
/// <summary>
/// Adds the cached request.
/// </summary>
/// <param name="reqMessage">The request message.</param>
private void AddCachedRequest(DsrRouteRequestMessage reqMessage)
{
var nodeCache = this.RequestCache.FirstOrDefault(r => r.Id.Equals(reqMessage.Sender));
if (nodeCache == null)
{
nodeCache = new NetSimRequestCacheEntry()
{
Id = reqMessage.Sender
};
this.RequestCache.Add(nodeCache);
}
nodeCache.CachedRequests.Add(reqMessage.RequestId);
}
/// <summary>
/// Handles the request route caching.
/// </summary>
/// <param name="reqMessage">The request message.</param>
public void HandleRequestRouteCaching(DsrRouteRequestMessage reqMessage)
{
// search for already cached route
var route = (DsrTableEntry)this.GetRouteFor(reqMessage.Sender);
// reverse the request route
var cachedRoute = reqMessage.Nodes.Reverse <string>().ToList();
if (route == null)
{
// add route to table
this.Entries.Add(
new DsrTableEntry()
{
Destination = reqMessage.Sender,
Route = cachedRoute,
Metric = cachedRoute.Count - 1
});
}
else
{
// check if new route is shorter
if (cachedRoute.Count < route.Metric)
{
// remove route and add new one
this.Entries.Remove(route);
// add new route
this.Entries.Add(
new DsrTableEntry()
{
Destination = reqMessage.Sender,
Route = cachedRoute,
Metric = cachedRoute.Count - 1
});
}
}
}
/// <summary>
/// Determines whether the given dsr route request message is a own request.
/// </summary>
/// <param name="reqMessage">The request message.</param>
/// <returns>
/// <c>true</c> if is own request; otherwise, <c>false</c>.
/// </returns>
private bool IsOwnRequest(DsrRouteRequestMessage reqMessage)
{
return(reqMessage.Nodes.Count > 0 && reqMessage.Nodes[0].Equals(this.Client.Id));
}
private void IncomingDsrRouteRequestMessageHandler(NetSimMessage message)
{
DsrTable dsrTable = (DsrTable)this.Table;
DsrRouteRequestMessage reqMessage = (DsrRouteRequestMessage)message;
// if duplicate
if (this.HasCachedRequest(reqMessage))
{
// ignore message and proceed
return;
}
// add request to cache
this.AddCachedRequest(reqMessage);
// add this node id to message Route
reqMessage.Nodes.Add(this.Client.Id);
// if this node was sender of request - ignore
if (this.IsOwnRequest(reqMessage))
{
return;
}
// cache route
dsrTable.HandleRequestRouteCaching(reqMessage);
// check if message destination is current node (me)
if (reqMessage.Receiver.Equals(this.Client.Id))
{
// send back rrep mesage the reverse way with found route
var response = new DsrRouteReplyMessage()
{
Receiver = reqMessage.Sender,
Sender = this.Client.Id,
Route = new List <string>(reqMessage.Nodes)
};
// enqueue message for sending
this.SendMessage(response);
return;
}
else
{
// Check if route to the end destination for request is cached
var route = this.Table.GetRouteFor(reqMessage.Receiver);
if (route != null)
{
var dsrRoute = (DsrTableEntry)route;
var newRoute = new List <string>(reqMessage.Nodes);
// remove last entry
newRoute.RemoveAt(newRoute.Count - 1);
// add cached route entries
newRoute.AddRange(dsrRoute.Route);
// send back rrep mesage the reverse way with found route
// note: sender is the orig. receiver of the req
var response = new DsrRouteReplyMessage()
{
Receiver = reqMessage.Sender,
Sender = reqMessage.Receiver,
Route = newRoute
};
// enqueue message for sending
this.SendMessage(response);
return;
}
}
// forward message to outgoing messages
this.SendMessage(reqMessage);
}
/// <summary>
/// Determines whether this protocol instance has cached request the specified request id.
/// </summary>
/// <param name="reqMessaged">The request messaged.</param>
/// <returns>
/// <c>true</c> if has cached request with the specified request message; otherwise, <c>false</c>.
/// </returns>
private bool HasCachedRequest(DsrRouteRequestMessage reqMessaged)
{
return
(this.RequestCache
.FirstOrDefault(r => r.Id.Equals(reqMessaged.Sender))?.HasCachedRequest(reqMessaged.RequestId) ?? false);
}
