No reception of NewConnection signal

cyte13

Hi everyone,

As a training, i wrote a server/client application:

A server exe, using my own class derivated from QTcpServer. Like examples, after listening on port, I connect signal newConnection with a slot (printing text to confirm a connection).
A client exe, using my own class derivated from QTcpSocket. After the connection with server, I connect the signal connected() with my own slot( printint text to confirm connection to the server).

=> At execution, for cleint side, I have my printed text confirming the connection : connected() signal correctly treaten and redirected.
For server side, nothing printed and in a debug, I notice that my slot is not called : the signal newConnection is not interceped....

Rk: It works once if only after the listenning function I call WaitForNewConnection() long enough for a client to connect on server before the end of wait time.....

Has someone an idea of the reason why I don't intercept the newConnection() signal?

Thanks a lot,

Cyte13

tony

A connection to newConnection() signal is all you need, after listen.

Can you post your code (not all, just the network part)?

cyte13

Thanks for your reply, it is what I think, but doesn' work...
Here is the threated version one:

I have my own CGameEngine class derivated from QThread which has as a member a pointeur to another class CGameEngineServer which derivated from QTcpServer:

GAMEENGINE:
@
class GAMEENGINE_EXPORT CGameEngine : public QThread
{
Q_OBJECT
public:
/** Constructeur par défaut */
CGameEngine(QObject *parent = 0);

/** Destructeur */
~CGameEngine();

/** 
    StartProcess    :    Lance le serveur de jeu local et gère la partie
    engineport        :    Port d'écoute du serveur local de jeu
    placeavailable    :    Nombre maximum de joueur à la table
    RETURN            :    GAMEENGINE_CORRECT ou GAMEENGINE_ERREUR
**/
void StartProcess(quint16 engineport, int placeavailable);

void run();

private:
//CComEngineBDD* MyComEngineBDD;
CGameEngineServer* MyEngineServer;
...

void CGameEngine::StartProcess(quint16 engineport, int placeavailable)
{
m_engineport = engineport;
m_MaxPlayer = placeavailable;

start();

}

void CGameEngine::run()
{
/* Create the server object /
MyEngineServer = new CGameEngineServer();
/ Start listenning on port in arg /
if (!MyEngineServer->Listen(m_engineport)) exit();
/ Connect signals between MyEngineServer and this to specify processes at a new incoming message */
QObject::connect(MyEngineServer, SIGNAL(MessageToRead(QString)), this, SLOT(MessageToRead(QString)));
exec();
}
@
GAMEENGINESERVER:
@
class GAMENETWORK_EXPORT CGameEngineServer : public QTcpServer
{
Q_OBJECT

public:
CGameEngineServer(QObject *parent = 0);

bool Listen(quint16 port);
void Close();

protected:
//void incomingConnection(int socketDescriptor);

private:
QVector<QTcpSocket*> m_VectorClient;
quint16 tailleMessage;

signals:
void MessageToRead(QString);

public slots:
void NewConnection();
void ReadMessage();
};

bool CGameEngineServer::Listen(quint16 port)
{
bool result = listen(QHostAddress::LocalHost, port);
if (result)
{
printf("Local Game Engine Server listenning on port %d...\n", port);
/* make connection for a new connction */
QObject::connect(this, SIGNAL(newConnection()), this, SLOT(NewConnection()));
}
else
{
printf("Unable for Local Game Engine Server to listen on port %d...\n", port);
}
return result;
}

@

and now the call to StartProcess :
@
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
CGameEngine MyGameEngine;
MyGameEngine.StartProcess(8500, 2);

return a.exec&#40;&#41;;

}
@

tony

Well, I've tried your code in my PC ... and it works :)

Just a strange thing, but it's not dependent on your code. Qt Creator does not show printf messages in "Application Output". But if you launch your program in a console, you'll see the message (I put a printf in NewConnection slot).

tony

Btw ... use qDebug() function to show message in Application Output ...

cyte13

all my printf worked fine but NewConnection...
As an example, at the start of listenning : printf("Local Game Engine Server listenning on port %d...\n", port); => works fine in the console....

tony

Well, your server starts fine (as netstat shows...)

I just make a "telnet 127.0.0.1 8500" and a NEW CONNECTION!!! (my message) appears.

Firewall? Do you connect to 127.0.0.1 and port 8500? I cannot see any other problem ...

cyte13

I desactived the firewall but nothing changed.
What is strang is that the client correctly onnects to the server and intercepts the connected() signal.
Moreover, I need to put the WaitForNewConnection() to be able to intercept newConnection() signal....

cyte13

telnet succeced in connecting to the server but still nothing in new connection!!!!

tony

well, the only thing left is that I can post my code and you'll check for any diff ...

@
#ifndef GAMESERVER_H
#define GAMESERVER_H

#include <QtCore>
#include <QtNetwork>

class CGameEngineServer;

class CGameEngine : public QThread
{
Q_OBJECT

quint16 m_engineport;

public:
/** Constructeur par défaut */
CGameEngine(QObject *parent = 0) : QThread(parent), MyEngineServer(0) { }

/** Destructeur */
~CGameEngine() { }

/**
    StartProcess    :    Lance le serveur de jeu local et gère la partie
    engineport        :    Port d'écoute du serveur local de jeu
    placeavailable    :    Nombre maximum de joueur à la table
    RETURN            :    GAMEENGINE_CORRECT ou GAMEENGINE_ERREUR
**/
void StartProcess(quint16 engineport, int placeavailable);

void run();

private:
CGameEngineServer* MyEngineServer;
};

class CGameEngineServer : public QTcpServer
{
Q_OBJECT

public:
CGameEngineServer(QObject *parent = 0) : QTcpServer(parent) { }

bool Listen(quint16 port);
void Close();

protected:
//void incomingConnection(int socketDescriptor);

private:
QVector<QTcpSocket*> m_VectorClient;
quint16 tailleMessage;

signals:
void MessageToRead(QString);

public slots:
void NewConnection() { printf("NEW CONNECTION!!!\n"); }
void ReadMessage() { }
};

#endif // GAMESERVER_H
@

@
#include "gameserver.h"

void CGameEngine::StartProcess(quint16 engineport, int placeavailable)
{
m_engineport = engineport;
// m_MaxPlayer = placeavailable;

start();

}

void CGameEngine::run()
{
/* Create the server object /
MyEngineServer = new CGameEngineServer();
/ Start listenning on port in arg /
if (!MyEngineServer->Listen(m_engineport)) exit();
/ Connect signals between MyEngineServer and this to specify processes at a new incoming message */
QObject::connect(MyEngineServer, SIGNAL(MessageToRead(QString)), this, SLOT(MessageToRead(QString)));
exec();
}

bool CGameEngineServer::Listen(quint16 port)
{
bool result = listen(QHostAddress::LocalHost, port);
if (result)
{
printf("Local Game Engine Server listenning on port %d...\n", port);
/* make connection for a new connction */
QObject::connect(this, SIGNAL(newConnection()), this, SLOT(NewConnection()));
}
else
{
printf("Unable for Local Game Engine Server to listen on port %d...\n", port);
}
return result;
}
@

@
#include <QtCore/QCoreApplication>

#include "gameserver.h"

int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
CGameEngine MyGameEngine;
MyGameEngine.StartProcess(8500, 2);

return a.exec&#40;&#41;;

}
@

I hope that this will help you solve your problem ...

cyte13

not better.....
The only difference between your code and mine is that the CGameEngine and CGameEngineServer are available via a library (ifdef GAMENETWORK_LIB

define GAMENETWORK_EXPORT Q_DECL_EXPORT

#else

define GAMENETWORK_EXPORT Q_DECL_IMPORT

#endif)

==> May cause the issue?

tony

I don't think so ... well, you can try :)

cyte13

I progress...
When removing all classes access by library and directly insert .h and .cpp files into my app folder, it workd fine!!!!

Thanks a lot.

But... I would like to understand why it does not work when using StartProcess from the CGameEngine got from a library...!!!!