check_bluetooth_battery

#!/bin/sh
#
# See  the INSTALL file for installation instructions
#
# Copyright (c) 2009-2011 ETH Zurich.
# Copyright (c) 2009-2021 Matteo Corti <matteo@corti.li>
#
# This module is free software; you can redistribute it and/or modify it
# under the terms of GNU general public license (gpl) version 3.
# See the LICENSE file for details.

VERSION=1.3.0
NAME="BLUETOOTH BATTERY"

################################################################################
# Functions

################################################################################
# Prints usage information
# Params
#   $1 error message (optional)
usage() {

    if [ -n "$1" ] ; then
        echo "Error: $1" 1>&2
    fi
    
    echo
    echo "Usage: check_bluetooth_battery [OPTIONS] -c critical -w warning"
    echo
    echo "Options:"
    echo "   -c critical"
    echo "   -w warning"
    echo "   -h, -?     this help message"
    echo "   -V         version"
    echo
    echo "Report bugs to: Matteo Corti <matteo@corti.li> or https://github.com/matteocorti/check_bluetooth_battery/issues"
    echo

    exit 3

}

################################################################################
# Exits with a critical message
# Params
#   $1 error message
critical() {
    echo "${NAME} CRITICAL: $1"
    exit 2
}

################################################################################
# Exits with a warning message
# Param
#   $1 warning message
warning() {
    echo "${NAME} WARN: $1"
    exit 1
}

################################################################################
# Exits with an 'unknown' status
# Param
#   $1 message
unknown() {
    echo "${NAME} UNKNOWN: $1"
    exit 3
}

check_value() {

    VALUE=$1

    if ! echo "${VALUE}" | grep -q '^[0-9][0-9]*$' ; then
        critical "${VALUE} is not a positive number"
    fi

    if [ "${VALUE}" -gt 100 ] ; then
        critical "${VALUE} is larger than 100"
    fi

}

################################################################################
# Checks if a given program is available and executable
# Params
#   $1 program name
# Returns 1 if the program exists and is executable
check_required_prog() {

    PROG=$(command -v "$1")

    if [ -z "${PROG}" ] ; then
        critical "cannot find $1"
    fi

    if [ ! -x "${PROG}" ] ; then
        critical "${PROG} is not executable"
    fi

}

get_level() {

    NAME=$1

    ioreg -r -l -n "$1" | grep  '"BatteryPercent"\ =' | sed 's/[^[:digit:]]//g' | head -n 1

}

get_air_pod_level() {

    NAME=$1

    defaults read /Library/Preferences/com.apple.Bluetooth | grep  "BatteryPercent${NAME}"  | tr -d \; | awk '{print $3}'
    
}

check_device() {

    device=$1
    name=$2
    description=$3

    level=$(get_level "${device}")
    if [ -z "${level}" ] ; then
	level=$(get_air_pod_level "${device}")
    fi

    if [ -n "${level}" ] ; then

        if [ -n "${VERBOSE}" ] ; then
            echo "${description} detected (battery ${level}%)"
        fi

	if [ "${device}" = 'Case' ] && [ "${level}" -eq 0 ] ; then
	    
            if [ -n "${VERBOSE}" ] ; then
		echo "empty ${description} detected (no battery level delivered)"
            fi
	    
	else
	
            PERFORMANCE="${PERFORMANCE} ${name}=${level};${WARNING};${CRITICAL};;"
            
            if [ -n "${STATUS}" ] ; then
		STATUS="${STATUS}, "
            fi
            STATUS="${STATUS}${name} ${level}%"
            
            device_found=1
            
            if [ "${level}" -lt "${WARNING}" ] ; then
		EXITW=1
            fi
            if [ "${level}" -lt "${CRITICAL}" ] ; then
		EXITC=1
            fi
	    
	fi
	
    else
        
        if [ -n "${VERBOSE}" ] ; then
            echo "no ${description} detected"
        fi

    fi

}
    

################################################################################
# Main
################################################################################

# process command line options
while getopts "c:w:h?Vv" opt; do
    case ${opt} in
        c )      CRITICAL=${OPTARG} ;;
        w )      WARNING=${OPTARG}  ;;
        h | \? ) usage ; exit 3;  ;;
        v )      VERBOSE=1        ;;
        V )      echo "check_bluetooth_battery version ${VERSION}"; exit 3; ;;
	* )      echo "Unknown option '${opt}'"; exit 3 ;;
    esac
done
shift $((OPTIND - 1))

################################################################################
# sanity checks

if [ -z "${CRITICAL}" ] ; then
    usage 'no critical limit specified'
    exit 3
fi

if [ -z "${WARNING}" ] ; then
    usage 'no warning limit specified'
    exit 3
fi

check_value "${CRITICAL}"
check_value "${WARNING}"

#######################
# Check needed programs

check_required_prog ioreg


    

check_device 'IOAppleBluetoothHIDDriver' 'keyboard' 'bluetooth keyboard'
check_device 'AppleBluetoothHIDKeyboard' 'keyboard' 'bluetooth keyboard'
check_device 'BNBMouseDevice'            'mouse'    'bluetooth mouse'
check_device 'BNBTrackpadDevice'         'trackpad' 'bluetooth trackpad'
check_device 'AppleHSBluetoothDevice'    'mouse'    'bluetooth mouse'

# check air pods
check_device 'Case'  'AirPodCase'  'AirPod Case'
check_device 'Left'  'LeftAirPod'  'Left AirPod'
check_device 'Right' 'RightAirPod' 'Right AirPod'

##############################################################################
# Checks

if [ -z "${device_found}" ] ; then
    critical "no device detected"
fi

if [ -n "${EXITC}" ] ; then
    echo "${NAME} CRITICAL - ${STATUS} |${PERFORMANCE}"
    exit 2
fi
    
if [ -n "${EXITW}" ] ; then
    echo "${NAME} WARNING - ${STATUS} |${PERFORMANCE}"
    exit 1
fi

echo "${NAME} OK - ${STATUS} |${PERFORMANCE}"

exit 0