net_if_pkt.c

uCOS-II V2.84 LM3S6965 TCPIP Demo

             return;                                            /* Prevent 'break NOT reachable' compiler warning.      */
    }


                                                                /* ----------------- UPDATE RX STATS ------------------ */
    switch (err_rx) {                                           /* Chk err from NetIF_Rx().                             */
        case NET_IF_ERR_NONE:
             NET_CTR_STAT_INC(NetIF_Pkt_StatRxPktProcessedCtr);
             break;


        case NET_ERR_INIT_INCOMPLETE:
        case NET_ERR_RX:
             NET_CTR_ERR_INC(NetIF_Pkt_ErrRxPktDiscardedCtr);   /* See Note #3.                                         */
             break;


        default:
             NetIF_Pkt_RxPktDiscard(pbuf);
             return;                                            /* Prevent 'break NOT reachable' compiler warning.      */
    }
}


/*$PAGE*/
/*
*********************************************************************************************************
*                                    NetIF_Pkt_RxHandlerLoadBal()
*
* Description : Handle network receive versus transmit load balancing.
*
* Argument(s) : none.
*
* Return(s)   : none.
*
* Caller(s)   : NetIF_RxTaskHandler().
*
* Note(s)     : (1) To balance network receive versus transmit packet loads for certain network connection
*                   types (e.g. stream-type connections), network receive & transmit packets SHOULD be 
*                   handled in an APPROXIMATELY balanced ratio.
*
*                   (a) Network task priorities & lock mechanisms partially maintain a balanced ratio 
*                       between network receive versus transmit packet handling.
*
*                       However, the handling of network receive & transmit packets :
*
*                       (1) SHOULD be interleaved so that for every few packet(s) received & handled, 
*                           several packet(s) should be transmitted; & vice versa.
*
*                       (2) SHOULD NOT exclusively handle receive nor transmit packets, even for a
*                           short period of time.
*
*                   (b) To implement network receive versus transmit load balancing :
*
*                       (1) The availability of network receive packets MUST be managed at the network 
*                           interface layer :
*
*                           (A) Increment the number of available network receive packets queued for
*                               each network packet received.
*
*                           (B) Decrement the number of available network receive packets queued for
*                               each received packet handled.
*
*                       (2) Certain network connections MUST periodically suspend network transmit(s) 
*                           to handle network receive packet(s) :
*
*                           (A) Suspend network transmit(s) if network receive packets are available.
*
*                           (B) Signal or timeout network transmit suspend(s) to restart transmit(s).
*
*                   See also 'NETWORK RECEIVE PACKET MACRO'S  Note #1'.
*********************************************************************************************************
*/

#if (NET_CFG_LOAD_BAL_EN == DEF_ENABLED)
static  void  NetIF_Pkt_RxHandlerLoadBal (void)
{
#if (CPU_CFG_CRITICAL_METHOD == CPU_CRITICAL_METHOD_STATUS_LOCAL)
    CPU_SR  cpu_sr;
#endif


    NET_RX_PKT_DEC();                                           /* Dec nbr q'd rx pkts avail (see Note #1b1B).          */

    Net_TxSuspendSignal();                                      /* Signal net tx suspend     (see Note #1b2B).          */
}
#endif


/*$PAGE*/
/*
*********************************************************************************************************
*                                      NetIF_Pkt_RxPktDiscard()
*
* Description : On any Packet-based Network Interface Receive errors, discard packet & buffer.
*
* Argument(s) : pbuf        Pointer to network buffer.
*
* Return(s)   : none.
*
* Caller(s)   : NetIF_Pkt_Rx().
*
* Note(s)     : none.
*********************************************************************************************************
*/

static  void  NetIF_Pkt_RxPktDiscard (NET_BUF  *pbuf)
{
    NET_CTR  *pctr;


#if (NET_CTR_CFG_ERR_EN == DEF_ENABLED)
    pctr = (NET_CTR *)&NetIF_Pkt_ErrRxPktDiscardedCtr;
#else
    pctr = (NET_CTR *) 0;
#endif
    NetBuf_FreeBuf((NET_BUF *)pbuf,
                   (NET_CTR *)pctr);
}


/*$PAGE*/
/*
*********************************************************************************************************
*                                      NetIF_Pkt_TxPktValidate()
*
* Description : (1) Validate network interface transmit packet parameters :
*
*                   (a) Packets with the following invalid parameters will be "silently discarded" :
*
*                       (1) Protocols other than supported protocols :
*                           (A) Frame
*
*                       (2) Total Length
*
*
* Argument(s) : pbuf        Pointer to network buffer to transmit network interface packet.
*               ----        Argument checked   in NetIF_Pkt_Tx().
*
*               pbuf_hdr    Pointer to network buffer header.
*               --------    Argument validated in NetIF_Pkt_Tx().
*
*               perr        Pointer to variable that will receive the return error code from this function :
*
*                               NET_IF_ERR_NONE                 Transmit packet validated.
*                               NET_ERR_INVALID_PROTOCOL        Invalid/unknown protocol type.
*                               NET_BUF_ERR_INVALID_IX          Invalid or insufficient buffer index.
*
* Return(s)   : none.
*
* Caller(s)   : NetIF_Pkt_Tx().
*
* Note(s)     : none.
*********************************************************************************************************
*/

#if (NET_ERR_CFG_ARG_CHK_DBG_EN == DEF_ENABLED)
static  void  NetIF_Pkt_TxPktValidate (NET_BUF      *pbuf,
                                       NET_BUF_HDR  *pbuf_hdr,
                                       NET_ERR      *perr)
{
#if ((NET_CTR_CFG_ERR_EN      == DEF_ENABLED)                    && \
     (CPU_CFG_CRITICAL_METHOD == CPU_CRITICAL_METHOD_STATUS_LOCAL))
    CPU_SR      cpu_sr;
#endif
    CPU_INT16U  ix;


                                                                /* ----------------- VALIDATE PROTOCOL ---------------- */
    switch (pbuf_hdr->ProtocolHdrType) {
        case NET_PROTOCOL_TYPE_FRAME:
             ix = pbuf_hdr->IF_HdrIx;
             break;


        case NET_PROTOCOL_TYPE_NONE:
        default:
             NET_CTR_ERR_INC(NetIF_Pkt_ErrTxProtocolCtr);
            *perr = NET_ERR_INVALID_PROTOCOL;
             return;                                            /* Prevent 'break NOT reachable' compiler warning.      */
    }

    if (ix == NET_BUF_IX_NONE) {
        NET_CTR_ERR_INC(NetIF_Pkt_ErrTxInvalidBufIxCtr);
       *perr = NET_BUF_ERR_INVALID_IX;
        return;
    }


   *perr = NET_IF_ERR_NONE;
}
#endif


/*$PAGE*/
/*
*********************************************************************************************************
*                                        NetIF_Pkt_TxPktFree()
*
* Description : Free network buffer.
*
* Argument(s) : pbuf        Pointer to network buffer.
*
* Return(s)   : none.
*
* Caller(s)   : NetIF_Pkt_Tx().
*
* Note(s)     : none.
*********************************************************************************************************
*/

static  void  NetIF_Pkt_TxPktFree (NET_BUF  *pbuf)
{
    NetBuf_FreeBuf((NET_BUF *)pbuf,
                   (NET_CTR *)0);
}


/*
*********************************************************************************************************
*                                        NetIF_Pkt_TxPktDiscard()
*
* Description : On any Transmit errors, discard packet & buffer.
*
* Argument(s) : pbuf        Pointer to network buffer.
*
*               perr        Pointer to variable that will receive the return error code from this function :
*
*                               NET_ERR_TX                      Transmit error; packet discarded.
*
* Return(s)   : none.
*
* Caller(s)   : NetIF_Pkt_Tx().
*
* Note(s)     : none.
*********************************************************************************************************
*/

static  void  NetIF_Pkt_TxPktDiscard (NET_BUF  *pbuf,
                                      NET_ERR  *perr)
{
    NET_CTR  *pctr;


#if (NET_CTR_CFG_ERR_EN == DEF_ENABLED)
    pctr = (NET_CTR *)&NetIF_Pkt_ErrTxPktDiscardedCtr;
#else
    pctr = (NET_CTR *) 0;
#endif
    NetBuf_FreeBuf((NET_BUF *)pbuf,
                   (NET_CTR *)pctr);

   *perr = NET_ERR_TX;
}


/*$PAGE*/
/*
*********************************************************************************************************
*                                             MODULE END
*
* Note(s) : (1) See 'MODULE  Note #1' & 'net_if_pkt.h  MODULE  Note #1'.
*********************************************************************************************************
*/

#endif                                                          /* End of pkt-based net IF module include (see Note #1).*/