wmcpuload-1.0.0/src/cpu_openbsd.c

   1 /*
   2  * cpu_openbsd - module to get cpu usage, for OpenBSD
   3  *
   4  * Copyright (C) 2001, 2002 Seiichi SATO <ssato@sh.rim.or.jp>
   5  *
   6  * Licensed under the GPL
   7  */
   8
   9 #ifdef HAVE_CONFIG_H
  10 #include "config.h"
  11 #endif
  12
  13 #include <stdio.h>
  14 #include <unistd.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include "cpu.h"
  18
  19 #include <sys/param.h>
  20 #include <sys/sysctl.h>
  21 #include <sys/dkstat.h>
  22
  23 void
  24 cpu_init(void)
  25 {
  26     /* You don't need initialization under OpenBSD */
  27     return;
  28 }
  29
  30 /* Returns the current CPU usage in percent */
  31 int
  32 cpu_get_usage(cpu_options *opts)
  33 {
  34     int total, used, result;
  35     static int pre_total, pre_used;
  36
  37     int mib[] = { CTL_KERN, KERN_CPTIME };
  38     unsigned long int cpu_time[CPUSTATES];
  39     size_t size = sizeof(cpu_time);
  40
  41     /* get cpu time*/
  42     if (sysctl(mib, 2, &cpu_time, &size, NULL, 0) < 0)
  43         return 0;
  44
  45     /* calc usage */
  46     used = cpu_time[CP_USER] + cpu_time[CP_SYS];
  47     if (!opts->ignore_nice) {
  48         used += cpu_time[CP_NICE];
  49     }
  50     total = used + cpu_time[CP_IDLE];
  51
  52     if (pre_total == 0) {
  53         result = 0;
  54     } else if ((total - pre_total) > 0) {
  55         result = 100 * (double)(used - pre_used) / (double)(total - pre_total);
  56     } else {
  57         result = 0;
  58     }
  59
  60     /* save used/total for next calculation */
  61     pre_used = used;
  62     pre_total = total;
  63
  64     return result;
  65 }