admin-tools/check-battery

   1 #!/usr/bin/env perl
   2
   3 $0 =~ s/^.*\/([^\/]+)$/$1/;
   4
   5 if(not $ENV{'BATTERY_LOW_ACTION'})
   6 {
   7         die "$0: Set BATTERY_LOW_ACTION environment to a command.\n";
   8 }
   9 if(not $ENV{'BATTERY_TIME_THRESHOLD'} and not $ENV{'BATTERY_PERCENTAGE_THRESHOLD'})
  10 {
  11         die "$0: Set BATTERY_TIME_THRESHOLD and/or BATTERY_PERCENTAGE_THRESHOLD environment to at most how many remaining sec or percentage will trigger the action.\n";
  12 }
  13 if(not $ENV{'MIN_UPTIME'})
  14 {
  15         die "$0: Set MIN_UPTIME environment to prevent firing action shortly after reboot.\n";
  16 }
  17
  18
  19 open my $fh, '/proc/uptime' or die "$0: $!";
  20 ($uptime) = <$fh> =~ /(\d+)/;
  21 close $fh;
  22
  23 if($uptime <= $ENV{'MIN_UPTIME'})
  24 {
  25         exit 0;
  26 }
  27
  28
  29 $highest_remaining_sec = undef;
  30 $highest_percent = undef;
  31
  32
  33 open my $pipe, '-|', 'acpi', '-b' or die "$0: $!";
  34 while(<$pipe>)
  35 {
  36         if(/(\d\d+):(\d\d):(\d\d) remaining/)
  37         {
  38                 my ($hour, $min, $sec) = ($1, $2, $3);
  39                 my $remaining_sec = $hour * 3600 + $min * 60 + $sec;
  40                 if($remaining_sec > $highest_remaining_sec)
  41                 {
  42                         $highest_remaining_sec = $remaining_sec;
  43                         $highest_remaining_time = "$hour:$min:$sec";
  44                 }
  45         }
  46         if(/(\d+)%/)
  47         {
  48                 my $percent = $1;
  49                 if($percent > $highest_percent)
  50                 {
  51                         $highest_percent = $percent;
  52                 }
  53         }
  54 }
  55 close $pipe;
  56
  57
  58 $message = sprintf "remaining percentage: %s%%, remaining time: %s.", $highest_percent // "unknown", $highest_remaining_time // "unknown";
  59 $fire_action = 0;
  60
  61 if($ENV{'BATTERY_TIME_THRESHOLD'} and defined $highest_remaining_sec and $highest_remaining_sec <= $ENV{'BATTERY_TIME_THRESHOLD'})
  62 {
  63         $message .= " Remaining time less than $ENV{'BATTERY_TIME_THRESHOLD'} sec.";
  64         $fire_action = 1;
  65 }
  66 if($ENV{'BATTERY_PERCENTAGE_THRESHOLD'} and defined $highest_percent and $highest_percent <= $ENV{'BATTERY_PERCENTAGE_THRESHOLD'})
  67 {
  68         $message .= " Less than $ENV{'BATTERY_PERCENTAGE_THRESHOLD'}% left.";
  69         $fire_action = 1;
  70 }
  71
  72 if($fire_action)
  73 {
  74         my $command = $ENV{'BATTERY_LOW_ACTION'};
  75         warn "$0: $message Running '$command'.\n";
  76         system $command;
  77 }
  78 else
  79 {
  80         warn "$0: $message No action.\n";
  81 }