/* etherInputDemo.c - Demo for using low-level ethernet input routines *//* Copyright 1984-1997 Wind River Systems, Inc. *//*modification history--------------------01e,06nov97,mm   added copyright.01d,22Sep97,mm   removed include <vxWorks.h> changed include "etherDemo.h" to 		 "in_etherDemo.h"01c,22Sep97,mm   added include<etherLib.h> ,<string.h> ,<stdio.h> and <errno.h>01b,22Sep97,mm   changed "if.h" to "net/if.h"01a,16Feb94,ms   modified and cleaned up for VxDemo.*/#include <etherLib.h> #include <string.h>#include <stdio.h>#include <errno.h>  #include "net/if.h"#include "netinet/if_ether.h"#include "in_etherDemo.h"/***************************************************************************** * etherInputDemo - Demo for using low-level ethernet input routines * * DESCRIPTION * *     Handles (receives) raw input frames (input data) from the network *     interface using ether input hook routine etHandle. * *     This is a simple demonstration of using low-level input ethernet  *     routines. The other half of the demonstration of using low-level *     output ethernet routines is in etherOutputDemo.c. etherInputDemo runs on *     one VxWorks system, and etherOutputDemo runs on an other VxWorks system *     in the same physical network. * * RETURNS: OK or ERROR *  * EXAMPLE: * *     To run this etherInputDemo task from the VxWorks shell do as follows:  *     -> sp (etherInputDemo) * */STATUS etherInputDemo ()    {    if (etherInputHookAdd (etHandle) == OK)	printf ("etherInputHookAdd successful\n");    else  	{        perror ("etherInputHook failed");        return (ERROR);        }    return (OK);    }/***************************************************************************** * etHandle - ether input hook routine for handling raw input frames from the *            network interface. This routine is executed at task level  *            interrupt service for input packets. * * RETURNS: TRUE or FALSE *  */BOOL etHandle (ifp, buffer, length)    struct ifnet	*ifp;    char		*buffer;    int			length;    {    struct ether_header		*ethHdr;    char 			*buffPtr;    int 			ix;    char                        tmp[25];    ethHdr = (struct ether_header *) buffer;    if (ntohs(ethHdr->ether_type) != (u_short) ET_TYPE)	return (FALSE); /* Not a user defined protocol type, hence 0 is passed                     * to indicate further processing of data to be handled by                      * higher level protocols (IP, TCP etc., ).                     */    /* Handle raw input frames.      * Data integrity check and printing the input message is done for      * demonstration purpose.     */    /* Check for data integrity error */    buffPtr = (char *) (buffer + sizeof (*ethHdr));    strncpy (tmp, buffPtr, strlen (etMessage));    for (ix = 0; ix < sizeof (etMessage); ++ix)	if (*buffPtr++ != etMessage [ix])	    break;    if (ix != strlen (etMessage))        {	logMsg ("etHandle: data integrity error at %d.\n", ix);	return (ERROR);	}    logMsg ("etHandle: data okay - message is : %s \n", tmp);    return (TRUE); /* non-zero value to imply hook routine has processed                    * the input and there is no need for further handling by                    * any higher level protocols (IP, TCP etc.)                     */    }