epan/timestats.c

   1 /* timestats.c
   2  * routines for time statistics
   3  * Copyrigth 2003 Lars Roland
   4  *
   5  * $Id$
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  24  */
  25
  26 #include "config.h"
  27
  28 #include "timestats.h"
  29
  30 /* Initialize a timestat_t struct */
  31 void
  32 time_stat_init(timestat_t *stats)
  33 {
  34         stats->num = 0;
  35         stats->min_num = 0;
  36         stats->max_num = 0;
  37         nstime_set_zero(&stats->min);
  38         nstime_set_zero(&stats->max);
  39         nstime_set_zero(&stats->tot);
  40         stats->variance = 0.0;
  41 }
  42
  43 /* Update a timestat_t struct with a new sample */
  44 void
  45 time_stat_update(timestat_t *stats, const nstime_t *delta, packet_info *pinfo)
  46 {
  47         if(stats->num==0){
  48                 stats->max=*delta;
  49                 stats->max_num=pinfo->fd->num;
  50                 stats->min=*delta;
  51                 stats->min_num=pinfo->fd->num;
  52         }
  53
  54         if( (delta->secs<stats->min.secs)
  55         ||( (delta->secs==stats->min.secs)
  56           &&(delta->nsecs<stats->min.nsecs) ) ){
  57                 stats->min=*delta;
  58                 stats->min_num=pinfo->fd->num;
  59         }
  60
  61         if( (delta->secs>stats->max.secs)
  62         ||( (delta->secs==stats->max.secs)
  63           &&(delta->nsecs>stats->max.nsecs) ) ){
  64                 stats->max=*delta;
  65                 stats->max_num=pinfo->fd->num;
  66         }
  67
  68         nstime_add(&stats->tot, delta);
  69
  70         stats->num++;
  71 }
  72
  73 /*
  74  * get_average - function
  75  *
  76  * function to calculate the average
  77  * returns the average as a gdouble , time base is milli seconds
  78  */
  79
  80 gdouble get_average(const nstime_t *sum, guint32 num)
  81 {
  82         gdouble average;
  83
  84         if(num > 0) {
  85                 average = (double)sum->secs*1000 + (double)sum->nsecs/1000000;
  86                 average /= num;
  87         }
  88         else {
  89                 average = 0;
  90         }
  91         return average;
  92 }