Qt5 slot being called multiple times from a single emit statement - qt

Question

I'm relatively new to Qt, but I have done a little searching around. I have a base class that handles UDP broadcasting, and does the connect statements in the constructor of the class like this:
NetworkConnection::NetworkConnection(QObject *parent)
: QObject(parent) // Based on QObject
, m_server_search( new QUdpSocket ) // Our UDP Broadcast socket
, m_waiting_for_server( false )
, m_found_server( false )
{
qDebug() << "NetworkConnection::constructor";
connect( m_server_search, SIGNAL(readyRead()), this, SLOT(serverResponse()), Qt::UniqueConnection );
if ( m_server_search->bind( QHostAddress::AnyIPv4, (quint16)PORT_MULTICAST, QUdpSocket::ShareAddress ) )
{
if ( m_server_search->joinMulticastGroup( QHostAddress( MULTICAST_GROUP ) ) )
{
connect( this, SIGNAL(broadcast(NetworkMessage)), this, SLOT(broadcast_message(NetworkMessage)), Qt::UniqueConnection );
this->m_ping_timer = this->startTimer(2000);
qDebug() << "Ping timer id=" << this->m_ping_timer;
} else qDebug() << "Couldn't start multicast listener";
} else qDebug() << "Couldn't bind multicast to port" << PORT_MULTICAST;
}
I set up a signal/slot interface for broadcasting:
signals:
void serverFound();
void serverNotFound();
void broadcast(NetworkMessage);
private slots:
void serverResponse();
void broadcast_message( NetworkMessage msg );
And broadcast_message looks like this:
void NetworkConnection::broadcast_message( NetworkMessage msg )
{
QByteArray raw = msg.toString();
qDebug() << "NetworkConnection::broadcast_message>" << raw;
if ( m_server_search->writeDatagram( raw.data(), raw.size(), QHostAddress(MULTICAST_GROUP), (quint16)PORT_MULTICAST ) < 1 ) qDebug() << "Failed broadcast last message";
}
My timer works well, and here is the code:
void NetworkConnection::timerEvent(QTimerEvent *event)
{
qDebug() << "NetworkConnection::timerEvent with id" << event->timerId() << "(ping timer=" << this->m_ping_timer << ")";
if ( event->timerId() == this->m_ping_timer )
{
qDebug() << "NetworkConnection::pingForServer";
if ( m_waiting_for_server && !m_found_server )
{
qDebug() << "Server not found!";
emit this->serverNotFound();
return;
}
if ( !m_found_server )
{
qDebug() << "Sending a ping to the server";
NetworkMessage msg( m_software_guid, get_microseconds(), QString("whoisaserver") );
emit this->broadcast( msg );
m_waiting_for_server = true;
m_found_server = false;
}
}
}
I only get the text "Sending a pint to the server" once, but my broadcast_message outputs it's qDebug() multiple times.
I'm not explicitly using multiple threads, and as you can see I'm using Qt::UniqueConnection, which is apparently having no affect?
SO why would the slot be called multiple times? I've even tried debugging it a little and just calling this->broadcast( ... ) without using emit, and it still gets called multiple times.
Edit: I just added a counter to the broadcast_message slot, and it gets called 340 times. Is there any significance to that?