check_sensors.sh

#!/bin/bash

CODE_OK=0
CODE_UNKNOWN=1
CODE_WARNING=2
CODE_CRITICAL=3

WARNING_THRESHOLD="80%"
CRITICAL_THRESHOLD="100%"
DEBUG=0

while getopts ":C:S:c:w:dh" OPT; do
    case "${OPT}" in
        C)
            CHIP="${OPTARG}"
            ;;
        S)
            SENSORS="${OPTARG}"
            ;;
        c)
            CRITICAL_THRESHOLD="${OPTARG}"
            ;;
        w)
            WARNING_THRESHOLD="${OPTARG}"
            ;;
        d)
            DEBUG=1
            ;;
        h)
            cat <<__USAGE_END__
$0 [-C <chip>] [-S <sensors>] [-w <warn>] [-c <crit>] [-d] [-h]

    -C <chip>     - to read sensors on certain chip
    -S <sensors>  - to read sensors matching certain regexp
    -w <warning>  - warning rate threshold (80% by default)
    -c <critical> - critical rate threshild (100% by default)
    -d            - to print debug info
    -h            - you've just done it :)
__USAGE_END__
                >&2
            exit ${CODE_UNKNOWN}
            ;;
        \?)
            echo "Invalid option: -${OPTARG}, see -h" >&2
            exit ${CODE_UNKNOWN}
            ;;
        :)
            echo "Option -${OPTARG} requires some argument, see -h" >&2
            exit ${CODE_UNKNOWN}
            ;;
    esac
done

if [ -z "${CHIP}" ]; then
    DATA=$(/bin/sensors -u)
else
    DATA=$(/bin/sensors -u "${CHIP}")
fi
if [ $? -ne 0 ]; then
    echo "Can't get sensors' data" >&2
    exit ${CODE_UNKNOWN}
fi

echo "${DATA}" | awk \
    -v CriticalT="${CRITICAL_THRESHOLD}" \
    -v WarningT="${WARNING_THRESHOLD}" \
    -v Sensors="${SENSORS}" \
    -v CodeOK="${CODE_OK}" \
    -v CodeUnknown="${CODE_UNKNOWN}" \
    -v CodeWarning="${CODE_WARNING}" \
    -v CodeCritical="${CODE_CRITICAL}" \
    -v Debug=${DEBUG} \
    '
function Croak(Sensor, Input, Threshold) {
    printf(\
        "%s sensor shows %0.3f whilst its threshold is %0.3f (%0.0f%)\n", \
        Sensor, Input, Threshold, Input / Threshold * 100 \
    )
}
function Finish(Sensor, Input, Threshold, Alarm) {
    if(Debug) {
        printf( \
            "Finishing the %s sensor: input is %0.3f threshold is %0.3f alarm flag is %0.3f\n", \
            Sensor, Input, Threshold, Alarm \
        )
    }
    if(length(Sensors)) {
        if(Sensor !~ Sensors) {
            return
        }
    }
    if(Alarm > 0) {
        printf("%s sensor in alarm state\n", Sensor)
        exit CodeCritical
    }
    if(match(CriticalT, /^([[:digit:]]+)%$/, matched)) {
        if ((length(Threshold) > 0) && (Input / Threshold * 100 >= matched[1])) {
            Croak(Sensor, Input, Threshold)
            exit CodeCritical
        }
    } else {
        if (Input >= CriticalT) {
            Croak(Sensor, Input, CriticalT)
            exit CodeCritical
        }
    }
    if(match(WarningT, /^([[:digit:]]+)%$/, matched)) {
        if ((length(Threshold) > 0) && (Input / Threshold * 100 >= matched[1])) {
            Croak(Sensor, Input, Threshold)
            exit CodeWarning
        }
    } else {
        if (Input >= WarningT) {
            Croak(Sensor, Input, WarningT)
            exit CodeWarning
        }
    }
}
// {
    if(match($0, /^([^:]+):$/, matched)) {
        SensorNew = matched[1]
        if(length(Sensor) > 0) {
            Finish(Sensor, Input, Threshold, Alarm)
        }
        Sensor = SensorNew
        Input = ""
        Threshold = ""
        Alarm = ""
    }
    if(match($0, /^[[:space:]]+([^:]+): ([0-9\.\-]+)$/, matched)) {
        Parameter = matched[1]
        Value = matched[2]
        if(Parameter ~ /_input$/) {
            Input = Value
        }
        if(Parameter ~ /_(max|crit|emergency)$/) {
            if (Value > Threshold) {
                Threshold = Value
            }
        }
        if(Parameter ~ /_alarm$/) {
            Alarm = Value
        }
    }
}
END {
    if(length(Sensor) > 0) {
        Finish(Sensor, Input, Threshold, Alarm)
    }
}'

STATUS="${?}"
if [ "${STATUS}" -lt 4 ]; then
    exit "${STATUS}"
else
    exit "${CODE_UNKNOWN}"
fi