/* xsh_ping.c - xsh_ping */

#include 
#include 
#include 

/*------------------------------------------------------------------------
 * xsh_ping - shell command to ping a remote host
 *------------------------------------------------------------------------
 */
shellcmd xsh_ping(int nargs, char *args[])
{
        uint32  ipaddr;                 /* IP address in binary         */
        int32   retval;                 /* Return value                 */
        int32   slot;                   /* Slot in ICMP to use          */
        static  int32   seq = 0;        /* Sequence number              */
        char    buf[56];                /* Buffer of chars              */
        int32   i;                      /* Index into buffer            */
        int32   nextval;                /* Next value to use            */

        /* For argument '--help', emit help about the 'ping' command    */

        if (nargs == 2 && strncmp(args[1], "--help", 7) == 0) {
                printf("Use: %s  address\n\n", args[0]);
                printf("Description:\n");
                printf("\tUse ICMP Echo to ping a remote host\n");
                printf("Options:\n");
                printf("\t--help\t display this help and exit\n");
                printf("\taddress\t an IP address in dotted decimal\n");
                return 0;
        }

        /* Check for valid number of arguments */

        if (nargs != 2) {
                fprintf(stderr, "%s: invalid arguments\n", args[0]);
                fprintf(stderr, "Try '%s --help' for more information\n",
                                args[0]);
                return 1;
        }

        if(dnslookup(args[1], &ipaddr) == SYSERR) {
                fprintf(stderr, "DNS cannot resolve %s\n", args[1]);
                return 1;
        }
        printf("Pinging %d.%d.%d.%d\n", (ipaddr>>24)&0xff,
                                                (ipaddr>>16)&0xff,
                                                (ipaddr>>8)&0xff,
                                                (ipaddr)&0xff);

        /* Register to receive an ICMP Echo Reply */

        slot = icmp_register(ipaddr);
        if (slot == SYSERR) {
                fprintf(stderr,"%s: ICMP registration failed\n", args[0]);
                return 1;
        }

        /* Fill the buffer with values - start with low-order byte of   */
        /*      the sequence number and increment                       */

        nextval = seq;
        for (i = 0; i