mkpaperd

#!/bin/sh

# This is free and unencumbered software released into the public domain.
#
# Anyone is free to copy, modify, publish, use, compile, sell, or
# distribute this software, either in source code form or as a compiled
# binary, for any purpose, commercial or non-commercial, and by any
# means.
#
# In jurisdictions that recognize copyright laws, the author or authors
# of this software dedicate any and all copyright interest in the
# software to the public domain. We make this dedication for the benefit
# of the public at large and to the detriment of our heirs and
# successors. We intend this dedication to be an overt act of
# relinquishment in perpetuity of all present and future rights to this
# software under copyright law.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.
#
# For more information, please refer to <http://unlicense.org/>

echo_error () {
	printf '%s: %s\n' "${0##*/}" "$*" >&2
}

die () {
	local EXIT_CODE=1
	if [ "$1" -ge 0 ] 2>/dev/null
	then
		EXIT_CODE=$(($1))
		shift
	fi
	if [ -n "$1" ]
	then
		echo_error "$1"
	fi
	exit $EXIT_CODE
}

nonzero_or_die () {
	if [ -z "$1" ]
	then
		shift
		die "$@"
	fi
}

command_or_die () {
	while [ $# -gt 0 ]
	do
		nonzero_or_die "$(command -v "$1")" "$1: command not found"
		shift
	done
}

perl_package_or_die () {
	command_or_die perl
	while [ $# -gt 0 ]
	do
		if perl -M"$1" -e '' 2>/dev/null
		then
			shift
			continue
		fi
		die "$1: perl package not found"
	done
}

echo_usage () {
	printf "usage: %s " "${0##*/}"
	echo '[-group GROUP] -jar JAR [-java JAVA] -mode (launchd|systemd) [-user USER] [-OPTIONS...] [--] [ARGUMENTS...]'
}
case "$1" in
	-h|-help|--help)
		echo_usage
		exit 0
esac

SEQUENCE_DELIMITER=''  # \037

GROUP=
JAR=
JAVA=
MODE=
OPTIONS=
USER=
while [ $# -gt 0 ]
do
	case "$1" in
		-group)
			nonzero_or_die "$2" "$1: option requires an argument"
			GROUP="$2"
			shift 2
			;;
		-jar)
			nonzero_or_die "$2" "$1: option requires an argument"
			case "$2" in
				/*)
					JAR="$2"
					;;
				*)
					JAR="$(pwd)/$2"
			esac
			shift 2
			;;
		-java)
			nonzero_or_die "$2" "$1: option requires an argument"
			case "$2" in
				/*)
					JAVA="$2"
					;;
				*)
					JAVA="$(pwd)/$2"
			esac
			shift 2
			;;
		-mode)
			nonzero_or_die "$2" "$1: option requires an argument"
			case "$2" in
				launchd|systemd)
					MODE="$2"
					;;
				*)
					die "$2: unsupported mode"
			esac
			shift 2
			;;
		-user)
			nonzero_or_die "$2" "$1: option requires an argument"
			USER="$2"
			shift 2
			;;
		--)
			shift
			break
			;;
		-*)
			if [ -z "$OPTIONS" ]
			then
				OPTIONS="$1"
			else
				OPTIONS="$OPTIONS$SEQUENCE_DELIMITER$1"
			fi
			shift
			;;
		*)
			break
	esac
done
nonzero_or_die "$JAR" "$(echo_usage)"
nonzero_or_die "$MODE" "$(echo_usage)"
if [ -z "$JAVA" ]
then
	command_or_die java
	JAVA="$(command -v java)"
fi

ARGUMENTS=
while [ $# -gt 0 ]
do
	if [ -z "$ARGUMENTS" ]
	then
		ARGUMENTS="$1"
	else
		ARGUMENTS="$ARGUMENTS$SEQUENCE_DELIMITER$1"
	fi
	shift
done

case "$MODE" in
	launchd)
		perl_package_or_die	HTML::Entities
esac

WORKING_DIRECTORY="${JAR%/*}"

launchd_escape () {
	echo "$1" | perl -MHTML::Entities -e 'print encode_entities(<>)'
}

launchd_is_depth_parameter () {
	case "$1" in
		-*)
			if [ "$1" -le 0 ] 2>/dev/null
			then
				return $(true)
			fi
	esac
	return $(false)
}

launchd_indent () {
	local DEPTH=0
	if launchd_is_depth_parameter "$1"
	then
		DEPTH=$(($1 * -1))
		shift
	fi
	if [ $DEPTH -eq 0 ]
	then
		printf '%s\n' "$*"
		return
	fi
	local INDENT=
	while [ $DEPTH -gt 0 ]
	do
		INDENT="$INDENT\t"
		DEPTH=$(($DEPTH - 1))
	done
	local IFS=$'\n'
	local RESULT=
	for LINE in $1
	do
		if [ -z "$RESULT" ]
		then
			RESULT="$INDENT$LINE"
		else
			RESULT="$RESULT\n$INDENT$LINE"
		fi
	done
	echo "$RESULT"
}

launchd_array () {
	local DEPTH=0
	if launchd_is_depth_parameter "$1"
	then
		DEPTH=$(($1 * -1))
		shift
	fi
	local CHILD_DEPTH=$(($DEPTH + 1))
	local RESULT=
	for SEQUENCE in "$@"
	do
		if [ -z "$SEQUENCE" ]
		then
			continue
		fi
		if [ -z "$RESULT" ]
		then
			RESULT="$(launchd_indent -$CHILD_DEPTH "$SEQUENCE")"
		else
			RESULT="$RESULT\n$(launchd_indent -$CHILD_DEPTH "$SEQUENCE")"
		fi
	done
	if [ -z "$RESULT" ]
	then
		echo "$(launchd_indent -$DEPTH "<array/>")"
		return
	fi
	echo "$(launchd_indent -$DEPTH "<array>")"
	echo "$RESULT"
	echo "$(launchd_indent -$DEPTH "</array>")"
}

launchd_true () {
	local DEPTH=0
	if launchd_is_depth_parameter "$1"
	then
		DEPTH=$(($1 * -1))
		shift
	fi
	echo "$(launchd_indent -$DEPTH "<true/>")"
}

launchd_false () {
	local DEPTH=0
	if launchd_is_depth_parameter "$1"
	then
		DEPTH=$(($1 * -1))
		shift
	fi
	echo "$(launchd_indent -$DEPTH "<false/>")"
}

launchd_boolean () {
	local DEPTH=0
	if launchd_is_depth_parameter "$1"
	then
		DEPTH=$(($1 * -1))
		shift
	fi
	case "$1" in
		true)
			launchd_true -$DEPTH
			;;
		false)
			launchd_false -$DEPTH
			;;
		*)
			die "$1: invalid boolean value"
	esac
}

launchd_integer () {
	local DEPTH=0
	if [ $# -gt 1 ]
	then
		if launchd_is_depth_parameter "$1"
		then
			DEPTH=$(($1 * -1))
			shift
		fi
	fi
	echo "$(launchd_indent -$DEPTH "<integer>$(($1))</integer>")"
}

launchd_string () {
	local DEPTH=0
	if launchd_is_depth_parameter "$1"
	then
		DEPTH=$(($1 * -1))
		shift
	fi
	local ESCAPED="$(launchd_escape "$1")"
	if [ -n "$ESCAPED" ]
	then
		echo "$(launchd_indent -$DEPTH "<string>$(launchd_escape "$1")</string>")"
	else
		echo "$(launchd_indent -$DEPTH "<string/>")"
	fi
}

launchd_string_or_empty () {
	local DEPTH=0
	if launchd_is_depth_parameter "$1"
	then
		DEPTH=$(($1 * -1))
		shift
	fi
	if [ -n "$1" ]
	then
		launchd_string -$DEPTH "$1"
	fi
}

launchd_string_sequence () {
	local DEPTH=0
	if launchd_is_depth_parameter "$1"
	then
		DEPTH=$(($1 * -1))
		shift
	fi
	local RESULT=
	if [ $# -gt 1 ]
	then
		local IFS="$1"
		shift
	fi
	local SEQUENCE="$1"
	for ITEM in $SEQUENCE
	do
		if [ -z "$RESULT" ]
		then
			RESULT="$(launchd_string -$DEPTH "$ITEM")"
		else
			RESULT="$RESULT\n$(launchd_string -$DEPTH "$ITEM")"
		fi
	done
	echo "$RESULT"
}

launchd_key () {
	local DEPTH=0
	if launchd_is_depth_parameter "$1"
	then
		DEPTH=$(($1 * -1))
		shift
	fi
	echo "$(launchd_indent -$DEPTH "<key>$1</key>")"
}

systemd_escape () {
	echo "$1" | perl -e 's/(["'\''\\])/\\$1/g' -p
}

systemd_quote () {
	if [ $# -eq 0 ]
	then
		return
	elif [ -z "$1" ]
	then
		echo '""'
		return
	fi
	local ESCAPED="$(systemd_escape $1)"
	if [ "$ESCAPED" = "$1" ]
	then
		echo "$ESCAPED"
	else
		echo "\"$ESCAPED\""
	fi
}

systemd_quote_or_empty () {
	if [ -n "$1" ]
	then
		systemd_quote "$1"
	fi
}

systemd_quote_sequence () {
	local RESULT=
	if [ $# -gt 1 ]
	then
		local IFS="$1"
		shift
	fi
	local SEQUENCE="$1"
	for ITEM in $SEQUENCE
	do
		if [ -z "$RESULT" ]
		then
			RESULT="$(systemd_quote "$ITEM")"
		else
			RESULT="$RESULT $(systemd_quote "$ITEM")"
		fi
	done
	echo "$RESULT"
}

case "$MODE" in
	launchd)
		ARGUMENTS="$(launchd_string_sequence -0 "$SEQUENCE_DELIMITER" "$ARGUMENTS")"
		GROUP="$(launchd_string_or_empty -0 "$GROUP")"
		JAR="$(launchd_string -0 "$JAR")"
		JAVA="$(launchd_string -0 "$JAVA")"
		OPTIONS="$(launchd_string_sequence -0 "$SEQUENCE_DELIMITER" "$OPTIONS")"
		USER="$(launchd_string_or_empty -0 "$USER")"
		WORKING_DIRECTORY="$(launchd_string -0 "$WORKING_DIRECTORY")"
		;;
	systemd)
		ARGUMENTS="$(systemd_quote_sequence "$SEQUENCE_DELIMITER" "$ARGUMENTS")"
		GROUP="$(systemd_quote_or_empty "$GROUP")"
		JAR="$(systemd_quote "$JAR")"
		JAVA="$(systemd_quote "$JAVA")"
		OPTIONS="$(systemd_quote_sequence "$SEQUENCE_DELIMITER" "$OPTIONS")"
		USER="$(systemd_quote_or_empty "$USER")"
		WORKING_DIRECTORY="$(systemd_quote "$WORKING_DIRECTORY")"
esac

echo_launchd_plist () {
	echo '<?xml version="1.0" encoding="UTF-8"?>'
	echo '<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">'
	echo '<plist version="1.0">'
	echo '<dict>'
	echo "$(launchd_key -1 ExitTimeOut)"
	echo "$(launchd_integer -1 90)"
	if [ -n "$GROUP" ]
	then
		echo "$(launchd_key -1 GroupName)"
		echo "$(launchd_indent -1 "$GROUP")"
	fi
	echo "$(launchd_key -1 KeepAlive)"
	echo "$(launchd_indent -1 '<dict>')"
	echo "$(launchd_key -2 SuccessfulExit)"
	echo "$(launchd_false -2)"
	echo "$(launchd_indent -1 '</dict>')"
	echo "$(launchd_key -1 Label)"
	echo "$(launchd_string -1 moe.minacle.minecraft.paperd)"
	echo "$(launchd_key -1 ProgramArguments)"
	echo "$(launchd_array -1 "$JAVA" "$OPTIONS" $(launchd_string -jar) "$JAR" "$ARGUMENTS")"
	if [ -n "$USER" ]
	then
		echo "$(launchd_key -1 UserName)"
		echo "$(launchd_indent -1 "$USER")"
	fi
	echo "$(launchd_key -1 WorkingDirectory)"
	echo "$(launchd_indent -1 "$WORKING_DIRECTORY")"
	echo '</dict>'
	echo '</plist>'
}

echo_systemd_unit () {
	echo '[Install]'
	echo 'WantedBy=multi-user.target'
	echo
	echo '[Service]'
	printf 'ExecStart=%s' "$JAVA"
	if [ -n "$OPTIONS" ]
	then
		printf ' %s' "$OPTIONS"
	fi
	printf ' -jar %s' "$JAR"
	if [ -n "$ARGUMENTS" ]
	then
		printf ' -- %s\n' "$ARGUMENTS"
	else
		echo
	fi
	if [ -n "$GROUP" ]
	then
		echo "Group=$GROUP"
	fi
	echo 'Restart=on-abnormal'
	echo 'RestartSec=30'
	echo 'SuccessExitStatus=143'
	echo 'TimeoutStopSec=90'
	echo 'Type=simple'
	if [ -n "$USER" ]
	then
		echo "User=$USER"
	fi
	echo "WorkingDirectory=$WORKING_DIRECTORY"
	echo
	echo '[Unit]'
	echo 'After=network.target'
	echo 'Description=Paper Minecraft Server'
	echo 'Wants=network-online.target'
}

case "$MODE" in
	launchd)
		echo "$(echo_launchd_plist)"
		;;
	systemd)
		echo "$(echo_systemd_unit)"
esac