components/OpenBSD/battery.c

   1 /* See LICENSE file for copyright and license details. */
   2 #include <errno.h>
   3 #include <stdio.h>
   4 #include <string.h>
   5 #include <sys/ioctl.h>
   6 #include <fcntl.h>
   7 #include <unistd.h>
   8 #include <machine/apmvar.h>
   9
  10 #include "../../util.h"
  11
  12 const char *
  13 battery_perc(const char *null)
  14 {
  15         struct apm_power_info apm_info;
  16         int fd;
  17
  18         fd = open("/dev/apm", O_RDONLY);
  19         if (fd < 0) {
  20                 fprintf(stderr, "open '/dev/apm': %s\n", strerror(errno));
  21                 return NULL;
  22         }
  23
  24         if (ioctl(fd, APM_IOC_GETPOWER, &apm_info) < 0) {
  25                 fprintf(stderr, "ioctl 'APM_IOC_GETPOWER': %s\n", strerror(errno));
  26                 close(fd);
  27                 return NULL;
  28         }
  29         close(fd);
  30
  31         return bprintf("%d", apm_info.battery_life);
  32 }