我实现了一个继承自ApplicationBase和UdpSocket的新应用。在handleSelfMessage（）函数中，我发送了广播以获取邻居，这很好用。在功能handleMessageWhenUp()中，我从邻居那里收到了问候消息，并且工作正常。
我的问题是：当我收到邻居发来的问候消息时，我得到了它的地址，因此我使用UdpSocket向他发送了XEDMsg，这时出现错误：
check_and_cast（）：无法转换（inet :: Indication *）ERROR来键入'inet :: Packet *'
这是我的代码：
class myApp : public ApplicationBase, public UdpSocket::ICallback
{
protected:
int localPort = -1, destPort = -1;
bool dontFragment = false;
const char *packetName = nullptr;
simtime_t startTime;
simtime_t stopTime;
// state
UdpSocket socket;
cMessage *selfMsg = nullptr;
cModule *host = nullptr;
cMessage *event = nullptr;
cPar *broadcastDelay = nullptr;
unsigned int sequencenumber = 0;
simtime_t helloInterval;
IInterfaceTable *ift = nullptr;
InterfaceEntry *interface80211ptr = nullptr;
int interfaceId = -1;
list<L3Address> neighbors;
/********** XED **********/
class XED
{
public:
L3Address originatorAddr, destinationAddr;
unsigned int random;
XED(const L3Address& originatorAddr, const L3Address& destinationAddr, unsigned int random)
: originatorAddr(originatorAddr), destinationAddr(destinationAddr), random(random) {};
bool operator==(const XED& other) const
{
return this->originatorAddr == other.originatorAddr && this->destinationAddr == other.destinationAddr
&& this->random == other.random;
}
};
list<XED> lr,ls;
protected:
virtual int numInitStages() const override { return NUM_INIT_STAGES; }
virtual void initialize(int stage) override;
virtual void handleMessageWhenUp(cMessage *msg) override;
void handleSelfMessage(cMessage *msg);
// lifecycle
virtual void handleStartOperation(LifecycleOperation *operation) override { start(); }
virtual void handleStopOperation(LifecycleOperation *operation) override { stop(); }
virtual void handleCrashOperation(LifecycleOperation *operation) override { stop(); }
void start();
void stop();
virtual void socketDataArrived(UdpSocket *socket, Packet *packet) override;
virtual void socketErrorArrived(UdpSocket *socket, Indication *indication) override;
virtual void socketClosed(UdpSocket *socket) override;
virtual double generateRandom();
public:
myApp() {}
~myApp();
};
Define_Module(myApp);
myApp::~myApp()
{
cancelAndDelete(selfMsg);
}
void myApp::initialize(int stage)
{
ApplicationBase::initialize(stage);
if (stage == INITSTAGE_LOCAL)
{
sequencenumber = 0;
ift = getModuleFromPar<IInterfaceTable>(par("interfaceTableModule"), this);
event = new cMessage("event");
broadcastDelay = &par("broadcastDelay");
helloInterval = par("helloInterval");
localPort = par("localPort");
destPort = par("destPort");
packetName = par("packetName");
startTime = par("startTime");
stopTime = par("stopTime");
}
else if (stage == INITSTAGE_ROUTING_PROTOCOLS)
{
registerService(Protocol::manet, nullptr, gate("socketIn"));
registerProtocol(Protocol::manet, gate("socketOut"), nullptr);
}
}
void myApp::handleSelfMessage(cMessage *msg)
{
if (msg == event)
{
auto hello = makeShared<HelloMsg>();
Ipv4Address source = (interface80211ptr->getProtocolData<Ipv4InterfaceData>()->getIPAddress());
hello->setChunkLength(b(128));
hello->setSrcAddress(source);
sequencenumber += 2;
hello->setSequencenumber(sequencenumber);
hello->setNextAddress(source);
hello->setHopdistance(1);
auto packet = new Packet("Hello", hello);
packet->addTagIfAbsent<L3AddressReq>()->setDestAddress(Ipv4Address(255, 255, 255, 255));
packet->addTagIfAbsent<L3AddressReq>()->setSrcAddress(source);
packet->addTagIfAbsent<InterfaceReq>()->setInterfaceId(interface80211ptr->getInterfaceId());
packet->addTagIfAbsent<PacketProtocolTag>()->setProtocol(&Protocol::manet);
packet->addTagIfAbsent<DispatchProtocolReq>()->setProtocol(&Protocol::ipv4);
send(packet, "socketOut");
packet = nullptr;
hello = nullptr;
scheduleAt(simTime()+helloInterval+broadcastDelay->doubleValue(), event);
bubble("Sending new hello message");
}
}
void myApp::handleMessageWhenUp(cMessage *msg)
{
if (msg->isSelfMessage())
{
handleSelfMessage(msg);
}
else if (check_and_cast<Packet *>(msg)->getTag<PacketProtocolTag>()->getProtocol() == &Protocol::manet)
{
auto recHello = staticPtrCast<HelloMsg>(check_and_cast<Packet *>(msg)->peekData<HelloMsg>()->dupShared());
if (msg->arrivedOn("socketIn"))
{
bubble("Received hello message");
Ipv4Address source = interface80211ptr->getProtocolData<Ipv4InterfaceData>()->getIPAddress();
Ipv4Address src;
unsigned int msgsequencenumber;
int numHops;
Ipv4Address next;
src = recHello->getSrcAddress();
msgsequencenumber = recHello->getSequencenumber();
next = recHello->getNextAddress();
numHops = recHello->getHopdistance();
if (src == source)
{
EV_INFO << "Hello msg dropped. This message returned to the original creator.\n";
delete msg;
return;
}
else
{
neighbors.push_back(src);
auto xed = makeShared<XedMsg>();
Ipv4Address source = (interface80211ptr->getProtocolData<Ipv4InterfaceData>()->getIPAddress());
xed->setChunkLength(b(128));
xed->setSrcAddress(source);
xed->setDstAddress(src);
double random = generateRandom();
xed->setRandom(random);
auto packet = new Packet("XED", xed);
socket.setOutputGate(gate("socketOut"));
socket.setCallback(this);
socket.bind(source, localPort);
emit(packetSentSignal, packet);
socket.sendTo(packet, src, destPort);
packet = nullptr;
xed = nullptr;
}
delete msg;
}
else
throw cRuntimeError("Message arrived on unknown gate %s", msg->getArrivalGate()->getName());
}
}
void myApp::start()
{
int num_80211 = 0;
InterfaceEntry *ie;
InterfaceEntry *i_face;
const char *name;
broadcastDelay = &par("broadcastDelay");
for (int i = 0; i < ift->getNumInterfaces(); i++)
{
ie = ift->getInterface(i);
name = ie->getInterfaceName();
if (strstr(name, "wlan") != nullptr)
{
i_face = ie;
num_80211++;
interfaceId = i;
}
}
if (num_80211 == 1)
interface80211ptr = i_face;
else
throw cRuntimeError("Node has found %i 80211 interfaces", num_80211);
scheduleAt(simTime() + uniform(0.0, par("maxVariance").doubleValue()), event);
}
double myApp::generateRandom()
{
double lower_bound = 10000;
double upper_bound = 100000;
uniform_real_distribution<double> unif(lower_bound,upper_bound);
default_random_engine re;
double a_random_double = unif(re);
return a_random_double;
}
void myApp::stop()
{
cancelEvent(event);
}
void myApp::socketDataArrived(UdpSocket *socket, Packet *packet)
{
emit(packetReceivedSignal, packet);
EV_INFO << "Received packet: " << UdpSocket::getReceivedPacketInfo(packet) << endl;
EV << "Data Arrived " << endl;
}
void myApp::socketErrorArrived(UdpSocket *socket, Indication *indication)
{
EV << "Error Arrived" << endl;
EV_WARN << "Ignoring UDP error report " << indication->getName() << endl;
delete indication;
}
void myApp::socketClosed(UdpSocket *socket)
{
EV << "Close socket" << endl;
}