#!/bin/bash
#-------------------------------------------------------------------------------------------------
#$Header$
#-------------------------------------------------------------------------------------------------
#This file is part of "Server Scripts, Automatic Maintenance, Cron", a set of scripts for
#performing automatic periodic maintenance on a Linux server.
#-------------------------------------------------------------------------------------------------
#This source code and any program in which it is compiled/used is provided under the MIT License,
#reproduced below.
#-------------------------------------------------------------------------------------------------
#Permission is hereby granted, free of charge, to any person obtaining a copy of
#this software and associated documentation files(the "Software"), to deal in the
#Software without restriction, including without limitation the rights to use,
#copy, modify, merge, publish, distribute, sublicense, and / or sell copies of the
#Software, and to permit persons to whom the Software is furnished to do so,
#subject to the following conditions :
#
#The above copyright notice and this permission notice shall be included in all
#copies or substantial portions of the Software.
#
#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
#IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
#FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
#AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
#LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
#OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
#SOFTWARE.
#-------------------------------------------------------------------------------------------------
#Powers off my Lenovo 11e server if the battery is too depleted.  Designed to be run every 1-5
#minutes.  It has its own cron entry (in /etc/crontab) because there is no guarantee that the
#Lenovo 11e built-in battery is robust enough to make it through the regular maintenance cron, so
#can't safely put this logic in there.  Between interrupting maintenance tasks and a hard power
#fail, the interruption is less of a threat than a hard power fail.
#----------------------------------------------------------------------------------------------------
#Delay for 120 seconds if the power_fail_occurred lockfile exists, indicating that we are restarting
#after a previous power fail.  The reason for the delay is to guard against a missing battery or
#a faulted battery -- if this occurs, it would be very hard to get the server running again without
#rescue media.  The 120 seconds gives time to rename this script or kill the cron process(es) or
#something so the system can be started and will not power off.
if [ -f /etc/cron.custom/lockfiles/power_failure_occurred ] ; then
   sleep 120
   rm /etc/cron.custom/lockfiles/power_failure_occurred
fi
#----------------------------------------------------------------------------------------------------
#If the file with information doesn't exist, shutdown.
if [ ! -f /sys/class/power_supply/BAT1/capacity ] ; then
   touch /etc/cron.custom/lockfiles/power_failure_occurred
   poweroff
fi
#----------------------------------------------------------------------------------------------------
#If the file contains unfavorable information, shutdown.
if [ `cat /sys/class/power_supply/BAT1/capacity` -lt 30 ] ; then
   touch /etc/cron.custom/lockfiles/power_failure_occurred
   poweroff
fi
#----------------------------------------------------------------------------------------------------