/*
**	$Header: /home/vikas/src/nocol/pingmon/RCS/pingmon.c,v 2.5 1998/07/31 18:31:26 vikas Exp $
*/

/*+
 *
 * DESCRIPTION
 *
 *	Runs the "ping" program to monitor a site. Marks a site as UP
 *	DOWN or UNKNOWN. It writes directly to the 'pingoutput' file
 *	instead of to a temporary file. Uses raw i/o calls.
 *
 *	This program opens the 'data file' supplied by the user and then
 *	creates the 'pingoutput' file. It then directly reads and writes
 *	from this file. On recieving a HUP signal, it rescans the 'data
 *	file' supplied by the user and continues.
 *
 *
*/

/*
 * MODIFICATIONS
 *
 * $Log: pingmon.c,v $
 * Revision 2.5  1998/07/31 18:31:26  vikas
 * Rewrite to use the new library functions.
 *
 * Revision 2.4  1994/06/09 21:15:24  vikas
 * Deleted the definition for inet_addr(), it is defined in arpa/inet.h
 *
 * Revision 2.3  1994/05/16  02:10:24  vikas
 * Major rewrite. Now uses the nocol_startup() call.
 *
 */ 
#ifndef lint
 static char rcsid[] = "$RCSfile: pingmon.c,v $ $Revision: 2.5 $ $Date: 1998/07/31 18:31:26 $" ;
#endif

#include "pingmon.h"			/* program specific defines	*/

#include <string.h>			/* For strcat() definitions	*/
#include <sys/file.h>
#include <signal.h>			/* For signal numbers		*/

/*+ 
 * Global variables
 */

static char  	*configfile;		/* Filename with list of nodes */
static char  	*datafile;		/* Name of output data file */
static char	*sender;		/* for the EVENT field */
static time_t 	pollinterval ;		/* Time between polls */

main (ac, av)
     int ac;
     char **av;
{
    extern char *optarg;
    extern int optind;
    int	fdout = 0;			/* File desc for output data file */
    register int c ;
    char *p ;
    time_t starttm, polltime ;

    prognm = av[0] ;				/* Save the program name */

#ifdef SENDER
    sender = SENDER ;
#else						/* delete the directory name */
    if ((sender = (char *)strrchr (prognm , '/')) == NULL)
      sender = prognm ;				/* no path in program name */
    else
      sender++ ;				/* skip leading '/' */
#endif

    ping = PING ;				/* defined while compiling */

    while ((c = getopt(ac, av, "do:p:")) != EOF)
      switch (c)
      {
       case 'd':
	  debug++ ;
	  break ;
       case 'o':				/* output datafile */
	  datafile = optarg ;
	  break ;
       case 'p':				/* ping command to use */
	  ping = optarg ;
	  break ;
       case '?':
       default:
	  fprintf (stderr, "%s: Unknown flag: %c\n", prognm, optarg);
	  help() ;
	  goto Cleanup ;
      }

    switch ( ac - optind )
    {
     case 0:					/* default input file */
	break ;
     case 1:
	configfile = av[optind];
	break ;
     default:
	fprintf (stderr, "%s Error: Too many 'hosts' files\n\n", prognm);
	help();
	goto Cleanup;
    }

    if (access(ping, F_OK | X_OK) != 0)	/* check if PING is executable	*/
    {
	perror (ping);
	nocol_done();
    }

    nocol_startup(&configfile, &datafile);

    if (debug)
      fprintf(stderr,
	      "(debug) %s: PING= '%s', CONFIGFILE= '%s', DATAFILE= '%s'\n",
	      prognm, ping, configfile, datafile) ;
    
/*    setjmp (env);			/* Save the environment in case	*/

    if (fdout != 0)			/* Say, recovering from longjmp	*/
      close(fdout);

    openeventlog() ;			/* for logging */
    if ( (fdout = open(datafile, O_RDWR|O_CREAT|O_TRUNC, DATAFILE_MODE)) < 0)
    {
	fprintf(stderr, "(%s) ERROR in open datafile ", prognm);
	perror (datafile);
	goto Cleanup ;
    }

    if (init_sites(fdout, configfile) == -1 )
      goto Cleanup ;

    /* poll_sites makes one complete pass over the list of nodes */
    while (1)			      		/* forever */
    {
	starttm = time((time_t *)NULL) ;	/* time started this cycle */
	if (poll_sites(fdout) == -1)		/* Polling error */
	  break ;

	if ( (polltime = time((time_t *)NULL) - starttm) < pollinterval)
	  sleep ((unsigned)(pollinterval - polltime));
    }
    /* HERE ONLY IF ERROR */
 Cleanup:
    nocol_done();

}	/***************** End of main *******************/
    
/*+ 
 * FUNCTION:
 * 	Brief usage
 */
help ()
{
    static char usage[] = " [-d (debug)]  [-o <output file>] [-p <ping command>] [configfile file]\n";

    fprintf(stderr, "\nUSAGE: %s %s\n\n", prognm, usage);
    fprintf(stderr,"\tThis program finds out the status of sites by ");
    fprintf(stderr,"sending out an ICMP ping request and writing\n");
    fprintf(stderr,"\tthe output into the file %s\n", datafile);

    fprintf(stderr,"\tBy default, the list of nodes to monitor is %s\n", 
	    configfile);
    fprintf(stderr,"\tbut can be changed on the command line.\n");

    fprintf(stderr,"\tThe 'node-file' format is:\n");
    fprintf(stderr,"\t\t POLLINTERVAL  <#secs>\n");
    fprintf(stderr,"\t\t <node> <ip-address>  [TEST]\n\n");
    fprintf(stderr,"\tThe program writes its pid in %s.pid and \n",prognm);
    fprintf(stderr,"\tif a new process starts, it kills the earlier one.\n");
    fprintf(stderr,"\tSending it a SIGUSR1 signal toggles debugging.\n");
    return (1);
}


/*
** FUNCTION
**
**	init_sites
**
**	This function writes to the LSTFILE. All sites in the CONFIGFILE
**	file are set to UNKNOWN status.
**
**	Careful while using 'localtime': the calue of the month varies from
**	0 - 11 and hence has to be incremented for the correct month.
*/

init_sites(fdout, configfile)
     int fdout ;			/* Output file descriptor	*/
     char *configfile;			/* Filename of the nodes file	*/
{
    FILE *p_nodes ;
    EVENT v;				/* Defined in NOCOL.H		*/
    char record[MAXLINE];
    struct tm *loctime ;
    time_t locclock ;			/* Careful, don't use 'long'	*/

    if ((p_nodes = fopen(configfile, "r")) == NULL)
    {
	fprintf(stderr, "%s error (init_sites) ", prognm) ;
	perror (configfile);
	return (-1);
    }

    /*
     * Fill in the static data stuff
     */
    bzero (&v, sizeof(v)) ;

    locclock = time((time_t *)0);
    loctime = localtime((long *)&locclock);

    v.mon = loctime->tm_mon + 1;	v.day = loctime->tm_mday;
    v.hour = loctime->tm_hour;		v.min = loctime->tm_min;

    strncpy (v.sender, sender, sizeof(v.sender) - 1);

    strncpy (v.var.name, VARNM, sizeof (v.var.name) - 1);
    strncpy (v.var.units, VARUNITS, sizeof (v.var.units) - 1);
    v.var.threshold = PING_THRES ;		/* num of packets lost	*/

    v.nocop = SETF_UPDOUN (v.nocop, n_UNKNOWN);	/* Set all to UNKNOWN	*/
    v.severity = E_INFO ;

    while(fgetLine(p_nodes,record,MAXLINE) > 0 ) 
    {
	char w1[MAXLINE], w2[MAXLINE], w3[MAXLINE];	/* Confg words	*/
	int rc;						/* return code	*/

	v.nocop = 0 ;				/* Init options to zero	*/
	*w1 = *w2 = *w3 = '\0' ;
	rc = sscanf(record,"%s %s %s", w1, w2, w3);
	if (rc == 0 || *w1 == '\0' || *w1 == '#')  /* Comment or blank 	*/
	  continue;

        if (strncmp(w1, "POLLINTERVAL", 12) == 0 || strncmp(w1, "pollinterval", 12) == 0)
        {
            char *p;                                    /* for strtol */
            pollinterval = (u_long)strtol(w2, &p, 0) ;
            if (p == w2)
            {
                fprintf(stderr,"(%s): Error in format for POLLINTERVAL '%s'\n",
                        prognm, w2) ;
                pollinterval = 0 ;              /* reset to default above */
            }
            continue ;
        }

	strncpy(v.site.name, w1, sizeof(v.site.name) - 1);
	strncpy(v.site.addr, w2, sizeof(v.site.addr) - 1);  /* no checks */

#ifdef	IPPING		/* For IP, check the IP address */
	if (*w2 >= '0' && *w2 <= '9')	/* is a digit */
	  if (inet_addr(w2) == -1)	/* bad address */
	  {
	      fprintf(stderr,
		      "(%s): Error in address '%s' for site '%s', ignoring\n",
		      prognm, w2, w1);
	      continue ;
	  }
#endif	/* IPPING */
	if (*w3 != '\0')			/* Some other keyword	*/
	{
	    if (strcmp(w3, "test") == 0 || strcmp(w3, "TEST") == 0)
	      v.nocop = v.nocop | n_TEST ;
	    else
	      fprintf(stderr, "%s: Ignoring unknown keyword- %s\n", prognm,w3);
	}

	if (write (fdout, (char *)&v, sizeof(v)) != sizeof(v))
	{
	    fprintf(stderr, "%s (write): %s\n", prognm, sys_errlist[errno]);
	    exit (1) ;
	}

    }					/* end: while			*/
    fclose (p_nodes);			/* Not needed any more		*/    
    return(1);				/* All OK			*/

}	/* end:  init_sites()	*/