[Quickfix-developers] sequence reset loop when receiving invalid messages

[Van G. E. (K. 41) <edd...@cr...>]

Hi,

when receiving a FIX message with e.g. two times the same field, the message is discarted. Upon the next valid message, a sequence number mismatch is detected and a sequence reset is sent. The remote engine resends the invalid message and we enter an infinite loop.

I've trace the problem to 

void Session::next( const std::string& msg ) 
{ QF_STACK_PUSH(Session::next) 
m_state.onIncoming( msg ); 
next( Message( msg, m_dataDictionary ) ); 
QF_STACK_POP } 


The problem is encountered in next( Message( msg, m_dataDictionary );
the next loop is not executed and the sequence number not increased
if the Message constructor throws an InvalidMessage.

I've solved the problem by catching the InvalidMessage


void Session::next( const std::string& msg )
{ QF_STACK_PUSH(Session::next)

  m_state.onIncoming( msg );
  try {
  Message my_msg( msg, m_dataDictionary );
  next( my_msg );
  }
  catch ( InvalidMessage& )
  {
  m_state.onIncoming( "INVALID MESSAGE RECEIVED" );
  Message my_msg ( msg, false );
  generateReject(my_msg,13);
  m_state.incrNextTargetMsgSeqNum();
  }


Unfortunately I do not know the exact reject reason 
I put 13 ( TAG_APPEARS_MORE_THAN_ONCE ) because that was the case here.

Could another Message constructor be used and the message validation be left for 
void Session::next( const Message& message ) ?


best regards,

Eddy Van Gelder