How to stop listening port on tcp communication properly with LWIP Stack ?

[oziesin]

Hello, I have a mcu that works as a tcp server. I listen 2 port for connection, if i want to stop listening what must i do ?

I use this function to initialise port

void TCPServerInitialise( U16 usPort )
{
	struct tcp_pcb *pstTcp_pcb;
 
	/* create new tcp pcb */
	pstTcp_pcb = tcp_new ();	// allocate new tcp_pcb
 
	if ( pstTcp_pcb != NULL )
	{
		err_t err;
 
		/* bind pcb to port */
		err = tcp_bind ( pstTcp_pcb, IP_ADDR_ANY, usPort );
 
		CONSOLE_PRINT_1( "Tcp_Bind Err : %d", err );
 
		if ( err == ERR_OK )
		{
			/* start tcp listening for pcb */
			pstTcp_pcb = tcp_listen( pstTcp_pcb );
 
			if ( usPort == stPRM.stTransParams.st485Cfg.usETHPort )
			{
				mLedEth485StatusSet()
				stTaskETH.pst_tcp_pcb_485 = pstTcp_pcb;
			}
 
			else if ( usPort == stPRM.stTransParams.st232Cfg.usETHPort )
			{
				mLedEth232StatusSet()
				stTaskETH.pst_tcp_pcb_232 = pstTcp_pcb;
			}
			/* initialize LwIP tcp_accept callback function */
			tcp_accept ( pstTcp_pcb, TCPServerAcceptCallback );
 
			CONSOLE_PRINT_1( "Port %d is up !", usPort );
		}
		else
		{
			EventInsert( eEventTcpInitFail );
			/* deallocate the pcb */
			memp_free ( MEMP_TCP_PCB, pstTcp_pcb );
		}
	}
}

I tried tcp_close ( stTaskETH.pst_tcp_pcb_232 ); and tcp_close ( stTaskETH.pst_tcp_pcb_232 ); but still i have issues tcp_close didnt clear variables.

[Bob S]

What about "tcp_close( pstTcp_pcb )" (i.e. close the instance that you are "listening" with? When you close the pcb that you get from the "accept" call, the "listen" pcb is still active.

[Piranha]

A very important question - does the project use RTOS? Also take a note that tcp_close() is not guaranteed to succeed.

By the way else if in the line 28 doesn't make sense. Take the if part away or introduce the third option with just an else.

[oziesin]

No, Project does not use RTOS. 

I use tcpcloseCallback function like below.

void TCPServerConnectCloseCallback( struct tcp_pcb *pstTpcb, struct echoserver *pstEs )
 {
	 if( pstTpcb == stTaskETH.pstEs485->pcb )
	 {
		 stTaskETH.pstEs485 = NULL; // must be here
		 mLedEth485StatusClear();
	 }
	 else if( pstTpcb == stTaskETH.pstEs232->pcb )
	 {
		 stTaskETH.pstEs232 = NULL; // must be here
		 mLedEth232StatusClear();
	 }
	 /* remove all callbacks */
   tcp_arg(pstTpcb, NULL);
   tcp_sent(pstTpcb, NULL);
   tcp_recv(pstTpcb, NULL);
   tcp_err(pstTpcb, NULL);
   tcp_poll(pstTpcb, NULL, 0);
 
   /* delete pstEs structure */
   if (pstEs != NULL)
   {
     mem_free(pstEs);
   }
 
   /* close tcp connection */
   tcp_close(pstTpcb);
 }

This function always close connection successfully from client side but i cannot close port listening. I hope i could explain clearly