#!/usr/bin/env bash
#
# Check_MK YUM Plugin - Check for upgradeable packages.
#
# The basic idea was borrowed from Jonathan Mills version of a YUM
# plugin - thank you! I wanted a plugin which not only monitors security
# updates and also had to change the output for a bit.
#
# Copyright 2013, Stefan Schlesinger <sts@ono.at>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or (at
# your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# DLC 12/16/2015 - Stole and modified from check_mk plugin to check_mk local check
# SYSENG-25369 12/12/2023 - refactored to check for the RPMDB corruption
#

INTERVAL=3600                           # interval to run yum updates
LOG="/tmp/check_updates_cache.log"  # default path to log file

# Unix time (seconds since Unix epoch)
START=$(date +%s)

cacheage ()
{
    file=$1
    now=`date +%s`
    mtime=`stat -c %Y $file`
    delta=$((now - mtime ))
    echo $delta
}

# Generate the list of updateable packages in $LOG
generate_cache ()
{
    if which yum >/dev/null; then
        if [ ! -e "/var/run/yum.pid" ]; then
            yum -v check-update 2>&1 \
                | sed 's/^.*--> //g' \
                | egrep -v 'excluded \(priority\)$' \
                | egrep -v '(^Keeping|^Removing|^Nothing|^Excluding|^Looking|^Loading)' \
                | egrep '\.(x86_64|i.86|noarch)' > $LOG

        fi
    fi
}

## Check for updates regulary
if [ ! -e $LOG ]; then
    touch $LOG
    generate_cache
else
    age=$(cacheage $LOG)
    if [ $age -ge $INTERVAL ]; then
        generate_cache
    fi
fi

COUNT=`cat $LOG | wc -l`

if [[ $COUNT -gt 20 ]]; then
    echo "$COUNT packages out of date"
    exit 1
  else
    echo "Updates are fine"
    exit 0
fi