#!/bin/sh
#
# THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
test -n "$1" || exit 1
HOST="$1"
COMMUNITY="public"
RRDFILES="/var/rrdtool"
IMAGES="/var/www/htdocs"
WATERMARK="OpenBSD Amsterdam - https://obsda.ms"
RRDTOOL="/usr/local/bin/rrdtool"
CPUINFO="/tmp/${HOST}-cpu.txt"
UPTIME=$(cat /tmp/${HOST}-uptime.txt)
NOW=$(date "+%Y-%m-%d %H:%M:%S %Z" | sed 's/:/\\:/g')

if ! test -f "${RRDFILES}/${HOST}-cpu.rrd"
then
echo "Creating ${RRDFILES}/${HOST}-cpu.rrd"
${RRDTOOL} create ${RRDFILES}/${HOST}-cpu.rrd \
	--step 300 \
	DS:ds0:GAUGE:600:U:U \
	RRA:MAX:0.5:1:20000
fi

snmpctl snmp walk ${HOST} community ${COMMUNITY} oid hrProcessorLoad | cut -d= -f2 > ${CPUINFO}
CORES=$(grep -cv "^0$" ${CPUINFO})
CPU_LOAD_SUM=$(awk '{sum += $1} END {print sum}' ${CPUINFO})
CPU_LOAD=$(echo "scale=2; ${CPU_LOAD_SUM}/${CORES}" | bc -l)

${RRDTOOL} update ${RRDFILES}/${HOST}-cpu.rrd N:${CPU_LOAD}

${RRDTOOL} graph ${IMAGES}/${HOST}-cpu.png \
	--start -43200 \
	--title "${HOST} - CPU" \
	--vertical-label "% CPU Used" \
	--watermark "${WATERMARK}" \
	DEF:CPU=${RRDFILES}/${HOST}-cpu.rrd:ds0:AVERAGE \
	AREA:CPU#FFCC00 \
	LINE2:CPU#CC0033:"CPU" \
	GPRINT:CPU:MAX:"Max\:%2.2lf %s" \
	GPRINT:CPU:AVERAGE:"Average\:%2.2lf %s" \
	GPRINT:CPU:LAST:" Current\:%2.2lf %s\n" \
	COMMENT:"\\n" \
	COMMENT:"  SUM CPU Load / Active Cores = % CPU Used\n" \
	COMMENT:"  Up for ${UPTIME} at ${NOW}"