release/src/router/radvd/timer.c

   1 /*
   2  *   $Id: timer.c,v 1.12 2011/02/22 00:20:40 reubenhwk Exp $
   3  *
   4  *   Authors:
   5  *    Pedro Roque               <roque@di.fc.ul.pt>
   6  *    Lars Fenneberg            <lf@elemental.net>
   7  *
   8  *   This software is Copyright 1996-2000 by the above mentioned author(s),
   9  *   All Rights Reserved.
  10  *
  11  *   The license which is distributed with this software in the file COPYRIGHT
  12  *   applies to this software. If your distribution is missing this file, you
  13  *   may request it from <pekkas@netcore.fi>.
  14  *
  15  */
  16
  17 #include "radvd.h"
  18
  19 struct timeval
  20 next_timeval(double next)
  21 {
  22         struct timeval tv;
  23         gettimeofday(&tv, NULL);
  24         tv.tv_sec += (int)next;
  25         tv.tv_usec += 1000000 * (next - (int)next);
  26         return tv;
  27 }
  28
  29 int
  30 timevaldiff(struct timeval const *a, struct timeval const *b)
  31 {
  32   int msec;
  33   msec = (a->tv_sec - b->tv_sec) * 1000;
  34   msec += (a->tv_usec - b->tv_usec) / 1000;
  35   return msec;
  36 }
  37
  38
  39 /* Returns when the next time should expire in milliseconds. */
  40 int
  41 next_time_msec(struct Interface const * iface)
  42 {
  43         struct timeval tv;
  44         int retval;
  45         gettimeofday(&tv, NULL);
  46         retval = timevaldiff(&iface->next_multicast, &tv);
  47         return retval >= 1 ? retval : 1;
  48 }
  49
  50 int
  51 expired(struct Interface const * iface)
  52 {
  53         struct timeval tv;
  54         gettimeofday(&tv, NULL);
  55         if(timevaldiff(&iface->next_multicast, &tv) > 0)
  56                 return 0;
  57         return 1;
  58 }
  59