tests/test-getloadavg.c

   1 /* Test of getting load average.
   2    Copyright (C) 2011-2018 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 #include <config.h>
  18
  19 #include <stdlib.h>
  20
  21 #include "signature.h"
  22 SIGNATURE_CHECK (getloadavg, int, (double [], int));
  23
  24 #include <errno.h>
  25 #include <stdio.h>
  26 #include <unistd.h>
  27
  28 static void
  29 check_avg (int minutes, double avg, int printit)
  30 {
  31   if (printit)
  32     printf ("%d-minute: %f  ", minutes, avg);
  33   else
  34     {
  35       /* Plausibility checks.  */
  36       if (avg < 0.01)
  37         printf ("suspiciously low %d-minute average: %f\n", minutes, avg);
  38       if (avg > 1000000)
  39         printf ("suspiciously high %d-minute average: %f\n", minutes, avg);
  40     }
  41   if (avg < 0 || avg != avg)
  42     exit (minutes);
  43 }
  44
  45 /* This program can also be used as a manual test, by invoking it with
  46    an argument; it then prints the load average.  If the argument is
  47    nonzero, the manual test repeats forever, sleeping for the stated
  48    interval between each iteration.  */
  49 int
  50 main (int argc, char **argv)
  51 {
  52   int naptime = 0;
  53
  54   if (argc > 1)
  55     naptime = atoi (argv[1]);
  56
  57   while (1)
  58     {
  59       double avg[3];
  60       int loads = getloadavg (avg, 3);
  61       if (loads == -1)
  62         {
  63           if (! (errno == ENOSYS || errno == ENOTSUP || errno == ENOENT))
  64             return 1;
  65           perror ("Skipping test; load average not supported");
  66           return 77;
  67         }
  68       if (loads > 0)
  69         check_avg (1, avg[0], argc > 1);
  70       if (loads > 1)
  71         check_avg (5, avg[1], argc > 1);
  72       if (loads > 2)
  73         check_avg (15, avg[1], argc > 1);
  74       if (loads > 0 && argc > 1)
  75         putchar ('\n');
  76
  77       if (naptime == 0)
  78         break;
  79       sleep (naptime);
  80     }
  81
  82   return 0;
  83 }