#!/bin/sh
#	ipp-status
#
#	Copyright (c) 2013-2017, by Eaton (R) Corporation. All rights reserved.
#
#	A shell script to request UPS status (power state, runtime remaining)
#	with upsc and aggregate the results as a table and an exit-status that
#	can be inspected to see if the system is reliably protected or should
#	better go into shut-down. Uses configuration variables of upsmon.conf.

#
# Global variables
#
NUT_DIR="/usr/local/ups"
NUT_CFG_DIR=""
for D in "$NUT_DIR/etc" "/etc/nut" "/etc/ups" ; do
	if [ -d "$D" ] && [ -f "$D/ups.conf" ] && [ -f "$D/ipp.conf" ] ; then
		NUT_CFG_DIR="$D"
		break
	fi
done
unset D
CONFIG_UPSMON="$NUT_CFG_DIR/upsmon.conf"
CONFIG_IPP="$NUT_CFG_DIR/ipp.conf"

# Do not normally mangle the LD_LIBRARY_PATH - it can impact system tools too
#LD_LIBRARY_PATH="$NUT_DIR/lib:/usr/lib:/lib:$LD_LIBRARY_PATH"
#export LD_LIBRARY_PATH

# Note: $NUT_DIR/xbin holds the wrappers to run NUT binaries with co-bundled
# third party libs and hopefully without conflicts induced for the OS binaries
PATH="$NUT_DIR/xbin:$NUT_DIR/sbin:$NUT_DIR/bin:$PATH"
export PATH

# Search for binaries under current PATH normally, no hardcoding
NUT_UPSC="upsc"
#NUT_UPSC="$NUT_DIR/xbin/upsc"

# Flag for support (or not) of early-shutdown on this host
SHUTDOWN_TIMER=-1

# Include IPP ipp.conf (may overwrite the above default values!)
if [ -f "$CONFIG_IPP" ] ; then
	. "$CONFIG_IPP"
fi

#
# We need capable awk
#
awk="awk"

# On Solaris, the default awk is a simple implementation
# lacking certain functions (most notably the match builtin function).
# Luckily, nawk is present to save the day...
test "`uname -s`" = "SunOS" && awk="nawk"


#
# Default settings
#

overall_status_enabled="yes"
overall_status_mode="verbose"
devices_status_enabled="yes"
devices_formatted="yes"


#
# Get devices info, mixing config and runtime info
# Note that some other scripts may be parsing this via "ipp-status -d",
# so only append fields in the end as this evolves
#
get_devices_info() {
	for dev in `$awk '/^MONITOR / { print $2 }' "$CONFIG_UPSMON"`; do
		status="`$NUT_UPSC "$dev" ups.status 2>/dev/null`"
		runtime="`$NUT_UPSC "$dev" battery.runtime 2>/dev/null`"
		batterypct="`$NUT_UPSC "$dev" battery.charge 2>/dev/null`"
		supplies="`get_pwr_value "$dev" | egrep '^[0-9]*$'`"
		upsmon_ms="`get_ms_value "$dev" | egrep 'master|slave'`"

		echo "$dev:$status:$runtime:$batterypct:$supplies:$upsmon_ms"
	done
}


#
# Get minimum of required power supplies
#
get_min_supplies() {
	$awk '/^[ \t]*MINSUPPLIES/ { print $2 }' \
		"$CONFIG_UPSMON" 2>/dev/null
}


#
# Get a UPS power value (count of this host's power sources fed by UPS=="$1")
#
get_pwr_value() {
	$awk '/^[ \t]*MONITOR/ {
		if (match($2, /'"$1"'(@.*)?/))
			print $3;
	}' "$CONFIG_UPSMON" 2>/dev/null
}

#
# Get a UPS master/slave value (influences shutdown sequence and poweroffs)
#
get_ms_value() {
	$awk '/^[ \t]*MONITOR/ {
		if (match($2, /'"$1"'(@.*)?/))
			print $NF;
	}' "$CONFIG_UPSMON" 2>/dev/null
	# NF: This is last field in MONITOR line. Or 6th. Currently...
}

#
# Overall status resolution - parsing helpers
#
parse_protectors_knowngood() {
	# Lists the UPSes which are known to this host and have stable power
	# (no regard to how many sources of this host they actually feed)
	onbattery_sdtimer="$1"	# set to yes to trigger a shutdown timer
				# when UPS are on battery
	$awk -v ob_sdtimer="${onbattery_sdtimer}" -F: '
	{
		status = $2;

		# UPS on bypass does not protect anything
		if (match(status, /^OL BYPASS/))
			;

		# Other online states are OK
		else if (match(status, /^OL/))
			print $1;

		# UPS on exhausted battery does not protect anything
		else if (match(status, /^OB LB/))
			;

		# - NOK when onbattery_sdtimer = yes
		# - OK otherwise
		else if (match(status, /^OB/))
			if (match(ob_sdtimer, /^yes/))
				;
			else
				print $1;
	}
	' | sort | uniq
}

parse_protectors_unknown() {
	# Lists the UPSes which are known to this host but have unknown power
	# state (e.g. communications not established, driver died, initially
	# WAITing for data after driver startup, etc.) - without regard as to
	# how many sources of this host they actually feed
	$awk -F: '
	{
		status = $2;

		# Do not cause immediate shutdown if UPS is not accessible
		# (driver or connection failure)
		if (status == "")
			print $1;

		# Do not cause immediate shutdown when waiting for UPS data
		else if (match(status, /WAIT/))
			print $1;
	}
	' | sort | uniq
}

#
# Overall status resolution - primary logic
#
overall_status() {
	devices_info="$1"
	onbattery_sdtimer="$2"	# set to yes to trigger a shutdown timer
				# when UPS are on battery

	# Get non-low battery UPSes (still protecting the system)
	protectors="`echo "$devices_info" | parse_protectors_knowngood "${onbattery_sdtimer}"`"
	protectors_unknown="`echo "$devices_info" | parse_protectors_unknown`"

	# Get total powervalue of protecting UPSes
	protectors_pwr_value=0
	protectors_unknown_pwr_value=0
	not_protectors=0

	for ups in $protectors; do
		pwr_value="`get_pwr_value "$ups"`"

		test -n "$pwr_value" || pwr_value=1

		if test "$pwr_value" -eq 0 ; then
			not_protectors="`expr $not_protectors + 1`"
		else
			protectors_pwr_value="`expr $protectors_pwr_value + $pwr_value`"
		fi
	done

	for ups in $protectors_unknown; do
		pwr_value="`get_pwr_value "$ups"`"

		test -n "$pwr_value" || pwr_value=1

		if test "$pwr_value" -eq 0 ; then
			not_protectors="`expr $not_protectors + 1`"
		else
			protectors_unknown_pwr_value="`expr $protectors_unknown_pwr_value + $pwr_value`"
		fi
	done

	# Resolve system protection status
	overall_status_str="protected"

	min_supplies="`get_min_supplies`" \
	&& test -n "$min_supplies" \
	&& test "$min_supplies" -ge 0 \
	|| min_supplies=1
	# Zero is a resonable value - monitoring station that doesn't shut down

	min_supplies_eff="$min_supplies"
	if test "$protectors_unknown_pwr_value" -gt 0; then
		min_supplies_eff="`expr $min_supplies - $protectors_unknown_pwr_value`"
		test "$min_supplies_eff" -ge 0 || min_supplies_eff=0
	fi

	if test "$protectors_pwr_value" -lt "$min_supplies_eff"; then
		overall_status_str="unprotected"
	fi

	# Overall status indication by exit code
	if test "$overall_status_mode" = "silent"; then
		test "$overall_status_str" = "unprotected" && exit 1
		exit 0

	# Short form of overall status
	elif test "$overall_status_mode" = "short"; then
		echo "$overall_status_str"

	# Verbose form of overall status
	elif test "$overall_status_str" = "unprotected"; then
		cat <<HERE
Your system IS NOT PROTECTED

Only $protectors_pwr_value power backups are available (out of $min_supplies required with $protectors_unknown_pwr_value ignored)
HERE
	else
		echo "Your system is protected ($protectors_pwr_value power backups out of $min_supplies required with $protectors_unknown_pwr_value ignored are available)"
	fi

	if test "$not_protectors" -gt 0 2>/dev/null ; then
		echo "Also, $not_protectors device(s) that do not feed this host are known and monitored"
	fi

	case "$onbattery_sdtimer" in
	[Yy][Ee][Ss])
		if test "$min_supplies_eff" != "$min_supplies" ; then
			echo "WARNING: Some UPSes are not available, but we ignored them since onbattery_sdtimer=yes" >&2
		fi ;;
	esac

	test "$overall_status_str" = "unprotected" && return 1
	return 0
}


#
# Devices status resolution
#
devices_status() {
	devices_info="$1"

	# No UPS devices found
	if test -z "$devices_info"; then
		cat <<HERE

No devices have been found.
Please check that upsd is running and that your UPS devices
have been configured.
HERE
		exit 1
	fi

	# Per-battery info
	echo "$devices_info" | $awk -F: '
	function external_settings() {
		devices_formatted = "yes" == "'"$devices_formatted"'";
	}

	function t2h_mm_ss(t) {
		sig = "";

		t = int(t);

		if (0 > t) {
			sig = "-";
			t = -t;
		}

		ss = t % 60;
		t  = int(t / 60);
		mm = t % 60;
		h  = int(t / 60);

		if (length(ss) < 2 && (0 != mm || 0 != h))
			ss = "0" ss;

		t = ss;

		if (0 != mm || 0 != h) {
			if (length(mm) < 2 && 0 != h)
				mm = "0" mm;

			t = mm ":" t;

			if (0 != h)
				t = h ":" t;
		}

		return sig t;
	}

	BEGIN {
		external_settings();

		id_width     = 20;
		status_width = 15;
		runt_width   = 10;
		chrg_width   =  8;
		sources_width = 8;
		upsmonms_width= 7;
		format_str = "%-" id_width "s%-" status_width "s%" runt_width "s%" chrg_width "s%" sources_width "s %-" upsmonms_width "s\n";

		if (devices_formatted) {
			printf("\nDevices status:\n\n");
			printf(format_str, "Identifier", "Status", " Runtime", "Charge%", "Sources", "UPSMon");
			printf(format_str, "----------", "------", "--------", "-------", "-------", "------");
		}
	}

	{
		id      = $1;
		status  = $2
		runtime = $3;
		charge  = $4;
		sources = $5;
		upsmon_ms = $6;

		# Resolve basic status
		if (status == "")
			status_str = "unknown";
		else if (match(status, /WAIT/))
			status_str = "unknown";
		else if (match(status, /^OL BYPASS/))
			status_str = "on bypass";
		else if (match(status, /^OL/))
			status_str = "online";
		else if (match(status, /^OB LB/))
			status_str = "low battery";
		else if (match(status, /^OB/))
			status_str = "on battery";
		else if (match(status, /OFF/))
			status_str = "off";
		else if (match(status, /FSD/))
			status_str = "forced shutdown";
		else
			status_str = "\"" status "\"";

		# Resolve status modifications
		if (match(status, /OVER/))
			status_str = status_str " (OVERLOADED)";
		else if (match(status, /TRIM/) || match(status, /BOOST/))
			status_str = status_str " (improving mains)";

		if (devices_formatted) {
			if (runtime != "")
				runtime = t2h_mm_ss(runtime);
			else
				runtime = "unknown";

			printf(format_str, id, status_str, runtime, charge, sources, upsmon_ms);
		}
		else {
			if (runtime != "")
				runtime = int(runtime);
			else
				runtime = "unknown";

			print id ":" status_str ":" runtime ":" charge ":" sources ":" upsmon_ms;
		}
	}
	'
}


#
# Usage
#
usage() {
	this="`basename $0`"

	cat <<HERE
Usage: $this [OPTIONS]

OPTIONS:
    -h                 Print this help and exit
    -S                 Don't show overall status
    -s                 Show overall status in short form of "(un)protected"
    -q                 Do not print anything; instead, exit with 0/non-0
                       if the system is/isn't protected, respectively
    -D                 Don't show devices status
    -d                 Show devices report in scripting-friendly form
    -p                 Parseable output only (-d -S)

Full devices status report consists of the device ID, its power status (as
a readable meaningful string), on-battery runtime in form [[H:]MM:]SS, the
percentage of the battery charged, the number of this machine's sources
this UPS feeds, and its upsmon master/slave setting.
In the short form (for scripting), the runtime is shown in seconds and the
six fields are separated by colon.

HERE
}


usage_and_exit() {
	exit_code="$1"

	test -n "$exit_code" || exit_code=0

	usage

	exit $exit_code
}


#
# Options
#

# Parse & unify command line arguments
# TODO: getopt may be unportable to older shells, revise to simpler constructs
options="`getopt 'hSsqDdp' $*`"

test $? = 0 || usage_and_exit 1 >&2

# Process options
set -- $options

while test "$1" != "--"; do
	case "$1" in
	-h)
		# Print usage
		usage_and_exit 0
		;;

	-S)
		# Don't show overall status
		overall_status_enabled="no"
		;;

	-s)
		# Short overall status indication
		overall_status_mode="short"
		;;

	-q)
		# Silent overall status indication
		overall_status_mode="silent"
		devices_status_enabled="no"
		;;

	-D)
		# Don't show devices status
		devices_status_enabled="no"
		;;

	-d)
		# Devices status shall not be formatted
		devices_formatted="no"
		;;

	-p)
		# Devices status shall not be formatted
		devices_formatted="no"
		# Don't show overall status
		overall_status_enabled="no"
		;;
	esac

	# Next option
	shift
done

# Shift the final "--"
shift


#
# Main
#

onbattery_sdtimer="no"
if test "$SHUTDOWN_TIMER" -gt -1 2>/dev/null ; then
	onbattery_sdtimer="yes"
fi

# Get devices info
devices_info="`get_devices_info`"

# Overall status
if test "$overall_status_enabled" = "yes"; then
	overall_status "$devices_info" "$onbattery_sdtimer"
fi

# Devices status
if test "$devices_status_enabled" = "yes"; then
	devices_status "$devices_info"
fi