Omnet++ Error setting parameter in child Class and calling it in another child Class

Question

I am trying to set a parameter in PassiveQueueBase which is child class and call it in another child class PriorityScheduler for Base Class IPassiveQueue.

PriorityScheduler is inherited from SchedulerBase which has a pointer (inputQueue) pointing at who ever is of type IpassiveQueue and going to invoke PacketEnqueued() function to PriorityScheduler. This is shown in this code

class INET_API SchedulerBase : public cSimpleModule, public IPassiveQueue, public IPassiveQueueListener
{
    public:
    virtual void packetEnqueued(IPassiveQueue *inputQueue) override;
};

Note: IpassiveQueue.h has no .cc file it is an interface file for many other classes.

What I tried to do is shown below,

class INET_API IPassiveQueue
{
  public:
    simtime_t sendWindowStart;
    simtime_t sendWindowEnd;
    virtual void setWindows() {};
};

class INET_API PassiveQueueBase : public cSimpleModule, public IPassiveQueue
{  protected:
    void setWindows(simtime_t SWS,simtime_t SWE);
};

void PassiveQueueBase :: setWindows(simtime_t SWS,simtime_t SWE)
{   SWS = 3;  SWE = 4;                  
sendWindowStart = SWS;               
sendWindowEnd = SWE;             
};

bool PriorityScheduler::schedulePacket()
{
IPassiveQueue *pqueue;
pqueue->setWindows();
sendWindowStart = inputQueue->sendWindowStart;
sendWindowEnd = inputQueue->sendWindowEnd;
}

I had an error by running the simulation as shown below

Simulation terminated with exit code: 139 Working directory: /home/usrname/omnetpp-5.0/samples/inet/examples/mysimulation Command line: opp_run -r 0 -n ..:../../src:../../tutorials -l ../../src/INET --debug-on-errors=false omnetpp.ini

Also I have exclamation mark on this line

pqueue->setWindows();

with this note

‘Pqueue’ may be used uninitialized in this function [-Wmaybe-uninitialized]

Answer 1

you have not allocated pqueue yet and you are using it.

IPassiveQueue *pqueue;

this one still points on unknown location on memory.

to fix this you can allocate it using new

IPassiveQueue *pqueue = new IPassiveQueue;

and make sure to delete it using delete

delete pqueue;

you could also allocate it using smart pointer which will be more safe

std::unique_ptr<IPassiveQueue> pqueue(new IPassiveQueue);