[Quickfix-developers] Logout and DoNotSend

[Olivier T. <oli...@ev...>]

Hi,

I'm using the C++ library of Quickfix 1.6.0

 

I've added a logout message to tradeclient. When I tested it with the
executor_cpp.exe, I have noticed that tradeclient was sending a duplicate
logout:

- Tradeclient send logout message

- Executor replies with a logout message

- Tradeclient re-sends a logout message! This seemed to be due to the fact
that the executor answer is so quick, being on the same machine, that
mState.sentLogout is not set.

 

In order to work-around this problem, I changed my Application::toAdmin() so
that it throws a DoNotSend exception when receiving a logout from the
counterparty (hoping that it will be handled like the DoNotSend exception
coming from Application::toApp() to manage possible duplicates). I had to
had a try/catch around the call to m_application.toAdmin() in sendRaw() (in
session.cpp)

 

The exception was caught fine, and the duplicate logout not sent. However,
the sequence number was incremented, even though the second logout was never
sent, so tradeclient and executor became out of sync. To remedy this, I had
to make a simple change (see source below) so that when the DoNotSend
exception is caught, the sequence number is not incremented. 

 

It seems to me that it never should be when there is a DoNotSend exception.
Has any one else come across this? Any comments on these changes? No big
deal I suppose, but I'd be interested in your views.

 

Cheers,

Olivier.

 

Modified sendRaw() in session.cpp:

 

bool Session::sendRaw( Message& message, int num )

{ QF_STACK_PUSH(Session::sendRaw)

 

  Locker l( m_mutex );

 

  try

  {

    bool result = false;

            bool notSent = false;

    Header& header = message.getHeader();

    MsgType msgType;

    header.getField( msgType );

 

    fill( header );

    std::string messageString;

 

    if ( num )

      header.setField( MsgSeqNum( num ) );

 

    if ( Message::isAdminMsgType( msgType ) )

    {

                        try{ // new try-catch

      m_application.toAdmin( message, m_sessionID );

      if (

        msgType == "A" || msgType == "5"

        || msgType == "2" || msgType == "4"

        || isLoggedOn()

      )

      result = send( message.toString(messageString) );

                        }

                        catch ( DoNotSend&) {

                                    notSent = true;

                        }

    }

    else

    {

      try 

      {

        m_application.toApp( message, m_sessionID );

        message.toString( messageString );

        if ( isLoggedOn() ) result = 

          send( messageString );

      }

      catch ( DoNotSend& ) {

                          notSent = true; // new Boolean to avoid sequence
number increment

              }

    }

 

    if ( !num && !notSent) // new condition before incrementing sequence
number

    {

      MsgSeqNum msgSeqNum;

      header.getField( msgSeqNum );

      m_state.set( msgSeqNum, messageString );

      m_state.incrNextSenderMsgSeqNum();

    }

    return result;

  }

  catch ( IOException& )

  { return false; }

 

  QF_STACK_POP

}