firestarter/firestarter

#! /bin/bash
#
# firestarter
# A desktop environment startup script
# Copyright (C) 2019 Vintage Salt <rehashedsalt@cock.li>
#
# Distributed under terms of the MIT license.
#
set -e

# Read-only set-once variables
declare -r _name="$(basename -- "$0")"
declare -r _sessionid="$(< /proc/self/sessionid)"
# Options
declare _optconfigdir="${XDG_CONFIG_HOME:-$HOME/.config}/${_name}"
declare _optdryrun
declare _optlogdir="$_optconfigdir/logs"
declare _optpregen
declare -i _opthelp
declare -i _optverbose
# Working variables
declare -a _args
declare _return

# Helper functions
log() {
	# Print a line to the terminal if _optverbose is greater than $2
	# $2 defaults to 0
	# loglevel 0: Daily-use messages
	# loglevel 1: Detailed but not quite debugging
	# loglevel 2: Definitely debugging
	[ -z "$1" ] && return 1
	if (( _optverbose >= ${2:-0} )); then
		printf "%s - %s\\n" "$(date -Iseconds)" "$1"
	fi
}
warn() {
	# Print a yellow line to the terminal, respecting _optverbose
	[ -z "$1" ] && return 1
	if (( _optverbose >= ${2:-0} )); then
		if [ -t 1 ]; then
			printf "\\e[33m%s\\e[0m\\n" "$1"
		else
			printf "WARN: %s\\n" "$1"
		fi
	fi
}
error() {
	# Print a red line to the terminal, exit if $2 is specified
	[ -z "$1" ] && return 1
	if [ -t 2 ]; then
		printf "\\e[31m%s\\e[0m\\n" "$1" 1>&2
	else
		printf "ERROR: %s\\n" "$1" 1>&2
	fi
	[ -z "$2" ] && return
	exit "${2:-1}"
}
has() {
	# Parse out all arguments and try to find them in path
	# If an argument cannot be found, set _return and fail
	for prog in "$@"; do
		if ! command -v "$prog" > /dev/null 2>&1; then
			_return="$prog"
			return 1
		fi
	done
	return 0
}

# Core program functions
gettarget() {
	# Parse a defaults file to get a target program
	[ -z "$1" ] && return 1
	[ -d "$1" ] && return 1
	[ -r "$1" ] || return 1
	# Every odd line is a condition
	# Every even one is a target
	local firstline
	while read -r checkline; do
		if [ -z "$firstline" ]; then
			if [ "$checkline" = "#.fsdefaults" ]; then
				firstline=1
				continue
			else
				return 50
			fi
		fi
		[ "${checkline#"#"}" != "$checkline" ] && continue
		read -r execline
		if bash -c "$checkline" > /dev/null 2>&1; then
			_return="$execline"
			return 0
		else
			continue
		fi
	done < "$1"
	return 2
}
genconfigs() {
	log "Creating default config setup in \"$_optconfigdir\""
	log "See firestarter -h for more information"
	# Audio daemon
	cat << EOF > "$_optconfigdir/audio-daemon"
#.fsdefaults
command -v pulseaudio
pulseaudio
EOF
	# Information bars
	cat << EOF > "$_optconfigdir/bar"
#.fsdefaults
command -v polybar && [ -r "$HOME/.config/polybar/launch.sh" ]
"$HOME/.config/polybar/launch.sh"
command -v tint2
tint2
command -v lxpanel
lxpanel
command -v lxqt-panel
lxqt-panel
command -v mate-panel
mate-panel
command -v xfce4-panel
xfce4-panel
EOF
	# Blue light filter
	cat << EOF > "$_optconfigdir/blue-light-filter"
#.fsdefaults
command -v redshift-gtk
redshift-gtk
command -v redshift
redshift
EOF
	# Compositor
	cat << EOF > "$_optconfigdir/compositor"
#.fsdefaults
[ -z "\$DISPLAY" ]
:
command -v unagi
unagi
command -v compton
compton
command -v xcompmgr
xcompmgr
EOF
	# Polkit authentication agents
	cat << EOF > "$_optconfigdir/polkit-agent"
#.fsdefaults
command -v lxqt-policykit-agent
lxqt-policykit-agent
command -v lxpolkit
lxpolkit
command -v mate-polkit
mate-polkit
command -v polkit-efl-authentication-agent-1
polkit-efl-authentication-agent-1
[ -x "/usr/lib/ts-polkitagent" ]
/usr/lib/ts-polkitagent
[ -x "/usr/lib/policykit-1-gnome/polkit-gnome-authentication-agent-1" ]
/usr/lib/policykit-1-gnome/polkit-gnome-authentication-agent-1
[ -x "/usr/lib/polkit-gnome/polkit-gnome-authentication-agent-1" ]
/usr/lib/polkit-gnome/polkit-gnome-authentication-agent-1
# Debian locations
# On generation time, your architecture is filled in here
[ -x "/usr/lib/$(uname -m)-linux-gnu/polkit-mate/polkit-mate-authentication-agent-1" ]
"/usr/lib/$(uname -m)-linux-gnu/polkit-mate/polkit-mate-authentication-agent-1"
[ -x "/usr/lib/$(uname -m)-linux-gnu/libexec/polkit-kde-authentication-agent-1" ]
"/usr/lib/$(uname -m)-linux-gnu/libexec/polkit-kde-authentication-agent-1"
# OpenSuSE locations
[ -x "/usr/lib/polkit-mate/polkit-mate-authentication-agent-1" ]
"/usr/lib/polkit-mate/polkit-mate-authentication-agent-1"
[ -x "/usr/lib/polkit-kde-authentication-agent-1" ]
"/usr/lib/polkit-kde-authentication-agent-1"
# Arch locations
[ -x "/usr/lib/mate-polkit/polkit-mate-authentication-agent-1" ]
/usr/lib/mate-polkit/polkit-mate-authentication-agent-1
[ -x "/usr/lib/polkit-kde-authentication-agent-1" ]
/usr/lib/polkit-kde-authentication-agent-1
# Fedora locations
[ -x "/usr/libexec/xfce-polkit" ]
/usr/libexec/xfce-polkit
[ -x "/usr/libexec/lxqt-policykit-agent" ]
/usr/libexec/lxqt-policykit-agent
[ -x "/usr/libexec/polkit-mate-authentication-agent-1" ]
/usr/libexec/polkit-mate-authentication-agent-1
[ -x "/usr/libexec/kf5/polkit-kde-authentication-agent-1" ]
/usr/libexec/kf5/polkit-kde-authentication-agent-1
[ -x "/usr/libexec/polkit-gnome-authentication-agent-1" ]
/usr/libexec/polkit-gnome-authentication-agent-1
EOF
	# Hotkey daemon
	cat << EOF > "$_optconfigdir/hotkey-daemon"
#.fsdefaults
[ -z "\$DISPLAY" ]
:
command -v sxhkd
sxhkd
command -v lxqt-globalkeysd
lxqt-globalkeysd
EOF
	# Network daemon
	cat << EOF > "$_optconfigdir/network-daemon"
#.fsdefaults
command -v nm-applet
nm-applet
EOF
	# Notification daemon
	cat << EOF > "$_optconfigdir/notification-daemon"
#.fsdefaults
[ -z "\$DISPLAY" ]
:
command -v dunst
dunst
command -v lxqt-notificationd
notificationd
EOF
	# Power daemons
	cat << EOF > "$_optconfigdir/power-daemon"
#.fsdefaults
command -v batterymon
batterymon
command -v cbatticon
cbatticon
command -v lxqt-powermangement
lxqt-powermanagement
command -v xfce4-power-manager
xfce4-power-manager
command -v mate-power-manager
mate-power-manager
[ -x "/usr/lib/$(uname -m)-linux-gnu/libexec/org_kde_powerdevil" ]
/usr/lib/$(uname -m)-linux-gnu/libexec/org_kde_powerdevil
command -v gnome-power-manager
gnome-power-manager
EOF
	# Runners
	# Note that rofi is not a daemon and is not included here
	cat << EOF > "$_optconfigdir/runner"
#.fsdefaults
command -v krunner
krunner
EOF
	# Settings daemons
	cat << EOF > "$_optconfigdir/settings-daemon"
#.fsdefaults
command -v xsettingsd
xsettingsd
command -v xsettings-kde
xsettingskde
command -v lxsettings-daemon
lxsettings-daemon
command -v xfsettingsd
xfsettingsd
command -v mate-settings-daemon
mate-settings-daemon
command -v gnome-settings-daemon
gnome-settings-daemon
EOF
	# System statistics glances
	cat << EOF > "$_optconfigdir/stat-glances"
#.fsdefaults
[ -z "\$DISPLAY" ]
:
# Note: the dumb sleep hack is because Conky crashes with window_type override if the WM hasn't loaded yet
# This gives the WM ample time to load up
command -v conky && [ -r "\${XDG_CONFIG_HOME:-$HOME/.config}/conky/conky.conf" ]
sleep 5 && conky
EOF
	# Wallpaper setters
	cat << EOF > "$_optconfigdir/wallpaper"
#.fsdefaults
[ -z "\$DISPLAY" ]
:
command -v feh && [ -r "$HOME/.fehbg" ]
~/.fehbg
command -v nitrogen
nitrogen --restore
EOF
	# Window managers
	cat << EOF > "$_optconfigdir/wm"
#.fsdefaults
[ -z "\$DISPLAY" ]
:
command -v 2bwm
2bwm
command -v aewm
aewm
command -v awesome
awesome
command -v bspwm
bspwm
command -v catwm
catwm
command -v cwm
cwm
command -v dwm
dwm
command -v evilwm
evilwm
command -v exwm
exwm
command -v fluxbox
fluxbox
command -v flwm
flwm
command -v fvwm
fvwm
command -v herbstluftwm
herbstluftwm
command -v i3
i3
command -v icewm
icewm
command -v jbwm
jbwm
command -v jwm
jwm
command -v lwm
lwm
command -v openbox
openbox
command -v pawm
pawm
command -v ratpoison
ratpoison
command -v twm
twm
command -v windowmaker
windowmaker
command -v wmii
wmii
command -v xmonad
xmonad
command -v xfwm4
xfwm4
command -v metacity
metacity
command -v mutter
mutter
command -v kwin
kwin
command -v tinywm
tinywm
EOF
}
step_preexecute() {
	# Special things that can't use simple configuration files
	[ -n "$_optdryrun" ] && return 0
	[ -r "$HOME/.xsessionrc" ] && . "$HOME/.xsessionrc"
	export XDG_CURRENT_DESKTOP="${XDG_CURRENT_DESKTOP:-firestarter}"
	# dbus
	if \
		[ -z "$DBUS_SESSION_BUS_ADDRESS" ] && \
		[ -n "$XDG_RUNTIME_DIR" ] && \
		[ "$XDG_RUNTIME_DIR" = "/run/user/$(id -u)" ] && \
		[ -S "$XDG_RUNTIME_DIR/bus" ]; then
		# We already have a bus started; use it
		export DBUS_SESSION_BUS_ADDRESS="unix:path=$XDG_RUNTIME_DIR/bus"
		hasdbus=1
	elif \
		[ -z "$DBUS_SESSION_BUS_ADDRESS" ] && \
		has dbus-launch; then
		# We have dbus but haven't started it yet
		eval "$(dbus-laucnh --exit-with-session --sh-syntax)"
		hasdbus=1
	else
		warn "Did not start dbus; some applications may misbehave"
	fi
	if [ -n "$hasdbus" ]; then
		has dbus-update-activation-environment && \
			dbus-update-activation-environment --verbose --systemd --all >/dev/null 2>&1
	fi
	unset hasdbus
	# kcminit/Qt settings
	if has kcminit; then
		log "Initializing KDE Control Module settings"
		kcminit >/dev/null 2>&1
		export XDG_CURRENT_DESKTOP="KDE"
	elif has qt5ct; then
		log "Initializing qt5ct"
		if [ -z "$QT_QPA_PLATFORMTHEME" ]; then
			export QT_QPA_PLATFORMTHEME="qt5ct"
			log "Exporting QT_QPA_PLATFORMTHEME as \"$QT_QPA_PLATFORMTHEME\"" 2
		else
			log "Using existing theme setting \"$QT_QPA_PLATFORMTHEME\"" 2
		fi
		if [ -z "$QT_AUTO_SCREEN_SCALE_FACTOR" ]; then
			export QT_AUTO_SCREEN_SCALE_FACTOR="0"
			log "Exporting QT_AUTO_SCREEN_SCALE_FACTOR as \"$QT_AUTO_SCREEN_SCALE_FACTOR\"" 2
		else
			log "Using existing scale factor \"$QT_AUTO_SCREEN_SCALE_FACTOR\"" 2
		fi
	fi
	# xhost
	if has xhost; then
		if xhost +si:localuser:"$(id -un)" >/dev/null 2>&1; then
			log "Session open to other sessions by this user"
		else
			warn "Failed to open session via xhost"
		fi
	fi
	# xresources
	if [ -n "$DISPLAY" ] && has xrdb && [ -r "$HOME/.Xresources" ]; then
		if xrdb "$HOME/.Xresources" >/dev/null 2>&1; then
			log "Loaded in .Xresources"
		else
			warn "Failed to load .Xresources"
		fi
	fi
	# xsetroot
	if has xsetroot; then
		log "Setting root window properties"
		xsetroot -cursor_name left_ptr
	fi
	# xset
	if has xset; then
		log "Disabling bell"
		xset -b
	fi
}
step_execute() {
	# Parse out our defaults lists and execute their targets
	if ! [ -d "$_optlogdir" ]; then
		if ! mkdir -p "$_optlogdir" >/dev/null 2>&1; then
			error "Failed to create log directory: \"$_optlogdir\"" 53
		fi
	fi
	for file in "$_optconfigdir"/*; do
		if ! [ -e "$file" ]; then
			log "No configuration files found; generating defaults"
			genconfigs
			step_execute
			return
		fi
		# Skip our logs directory
		[ "$_optlogdir" == "$file" ] && continue
		local filename="$(basename -- "$file")"
		local logfile="$_optlogdir/$filename.log"
		if gettarget "$file"; then
			# It's a defaults file with a selected target
			target="$_return"
			log "Found target for $filename: \"$target\""
			[ -n "$_optdryrun" ] && continue
			if [ -f "$logfile" ]; then
				[ -f "$logfile.old" ] && rm "$logfile.old"
				mv "$logfile" "$logfile.old"
			fi
			bash -c "$target" > "$logfile" 2>&1 &
		elif [ $? = 50 ] && [ -x "$file" ]; then
			# It's a shell script or executable symlink
			log "Executing file: \"$filename\""
			[ -n "$_optdryrun" ] && continue
			"$file" > "$logfile" 2>&1 &
		else
			warn "Could not execute file: \"$filename\""
		fi
	done
}
step_postexecute() {
	# Wait for the WM to initialize, if one was found and we have the tools
	if [ -z "$FS_NOWAITWM" ] && gettarget "$_configdir/wm" && has xprop grep; then
		log "Waiting for WM to initialize: \"$_return\""
		for (( i=0; i<10; i++ )); do
			line="$(xprop -root | grep ^_NET_WM_NAME | grep -o '"\S*"$')"
			if [ -n "$line" ]; then
				log "WM has initialized, _NET_WM_NAME atom reads: $line"
				break
			fi
			read -t 1 -u 1023
		done
	fi
	# Dumb polybar workaround
	killall polybar -SIGUSR1
	# Execute a user rc if it exists
	local firestarterrc="$HOME/.firestarterrc"
	if [ -r "$firestarterrc" ] && [ -z "$dryrun" ]; then
		log "Executing rc script: $firestarterrc"
		"$firestarterrc"
	fi
	# Start XDG autostarters, if they exist
	if [ -z "$_optdryrun" ]; then
		if has dex; then
			dex -a >/dev/null 2>&1
		elif has fbautostart; then
			fbautostart > /dev/null 2>&1
		elif has xdg-autostart; then
			xdg-autostart ${XDG_CURRENT_DESKTOP:-firestarter}
		else
			warn "Could not find an XDG autostarter"
		fi
	fi
}
step_wait() {
	[ -n "$_optdryrun" ] && exit 0
	trap step_logout EXIT
	if [ -n "$FS_DIEONWM" ] && gettarget "$_configdir/wm" && has readlink "$_return"; then
		target="$(command -v "$_return")"
		for job in $(jobs -p); do
			if [ "$target" = "$(readlink /proc/$job/exe)" ]; then
				log "Waiting for WM to exit: \"$_return\""
				wait "$job"
				exit 0
			fi
		done
		warn "Could not find WM: \"$target\""
	fi
	log "Waiting for programs to exit"
	wait
	exit 0
}
step_logout() {
	log "Logging out"
	if has loginctl; then
		# Use loginctl if possible
		if [ -n "$_sessionid" ]; then
			loginctl terminate-session "$_sessionid"
		fi
	else
		# Otherwise just brute it out
		kill $(jobs -p)
	fi
	return 0
}

printhelp() {
	cat << EOF
Usage: $_name [OPTION]...

  -d			Perform a dry run; print what programs would have been
			executed instead of doing so
  -g			Regenerate default configs. This will clobber
  -h			Print this help text
  -v			Print more status messages. Stacks

Environment Variables:

  FS_DIEONWM		If nonempty, end the session when the WM dies.
  FS_NOWAITWM		If nonempty, skip waiting for the WM to initialize

Copyright (c) 2019 rehashedsalt@cock.li
Licensed under the MIT license
EOF
}

# Main
main() {
	# Parse out arguments
	while [ -n "$1" ]; do
		# Parse out flags
		while getopts ":dghv" opt; do
			case $opt in
				d)
					_optdryrun=1
					;;
				g)
					_optpregen=1
					;;
				h)
					_opthelp=1
					;;
				v)
					_optverbose+=1
					;;
				:)
					error "Option requires argument: -$OPTARG" 2
					;;
				*)
					error "Invalid option: -$OPTARG" 2
					;;
			esac
		done
		# Store arguments
		shift $((OPTIND - 1))
		if [ -n "$1" ]; then
			_args+=("$1")
			shift
		fi
		unset OPTIND
	done
	# Early hook for help
	[ -n "$_opthelp" ] && printhelp && exit 0
	# Early hook for generating configs
	if [ -n "$_optpregen" ]; then
		genconfigs
		exit $?
	fi
	# Ensure our running environment is sane and that we're not about to nest
	if [ -z "$_optdryrun" ] && [ -z "$_optpregen" ]; then
		for pid in $(pgrep firestarter); do
			# Skip invalid PIDs
			! [ -d "$/proc/$pid" ] && continue
			# If it's not our session then who cares
			[ "$_sessionid" != "$(< "/proc/$pid/sessionid")" ] && continue
			# If it's us then who cares
			[ "$pid" == "$BASHPID" ] && continue
			# We care
			error "Firestarter is already running: $pid" 40
		done
	fi
	if ! [ -d "$HOME" ] || ! [ -r "$HOME" ]; then
		error "Home directory not found or inaccessable: \"$HOME\"" 54
	fi
	if ! [ -d "$_optconfigdir" ]; then
		if [ -f "$_optconfigdir" ]; then
			error "Config directory is a file, should be directory: \"$_optconfigdir\"" 52
		fi
		if ! mkdir -p "$_optconfigdir" > /dev/null 2>&1; then
			error "Failed to find or create config directory: \"$_optconfigdir\"" 52
		fi
	fi
	# Validate core program dependencies
	log "Validating dependencies" 2
	if ! has basename; then
		error "Failed to find program: $_return" 1
	fi

	# Do the do
	[ -n "$_optdryrun" ] && log "Performing a dry run"
	step_preexecute
	step_execute
	step_wait
	step_logout
	exit 0
}

main "$@"