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.
#

# "Globals"
_name="firestarter"
_configdir="${XDG_CONFIG_HOME:-$HOME/.config}/$_name"
_logdir="${XDG_DATA_HOME:-$HOME/.local/share}/$_name/logs"
_firestarterrc="$HOME/.firestarterrc"
_sessionid="$(< /proc/self/sessionid)"

# Basic functions
print() {
	# Write a message to STDOUT without a name attached
	[ -z "$1" ] && return 1
	printf "%s\\n" \
		"$1"
}
log() {
	# Write a message to STDOUT
	[ -z "$1" ] && return 1
	printf "%s log: %s\\n" \
		"$_name" \
		"$1" >&1
}
err() {
	# Write a message to STDERR, also exit if arg 2 is specified
	[ -z "$1" ] && return 1
	printf "%s err: %s\\n" \
		"$_name" \
		"$1" >&2
	[ -z "$2" ] && return 0
	if ! [ "$2" -ge "0" ] > /dev/null 2>&1; then
		err "Attempted to exit with malformed exit code \"$2\"" 10
	else
		exit "$2"
	fi
}
startfile() {
	# Start a program using an alternatives list
	[ -z "$1" ] && return 1
	! [ -r "$1" ] && return 2
	if [ -x "$1" ]; then
		# File is a script
		"$1" &
		disown "$!"
	else
		# File is a defaults file
		while read line; do
			echo "$line"
		done < "$1"
	fi
}

# Steps in execution
step_generate() {
	log "Creating default config setup in \"$_configdir\""
	log "See firestarter -h for more information"
	# Audio daemon
	cat << EOF > "$_configdir/audio-daemon"
command -v pulseaudio
pulseaudio
EOF
	# Information bars
	cat << EOF > "$_configdir/bar"
command -v tint2
tint2
command -v polybar && [ -r "$HOME/.config/polybar/launch.sh" ]
"$HOME/.config/polybar/launch.sh"
command -v lxpanel
lxpanel
command -v lxqt-panel
lxqt-panel
command -v mate-panel
mate-panel
command -v xfce4-panel
xfce4-panel
EOF
	# Blue light filter
	cat << EOF > "$_configdir/blue-light-filter"
command -v redshift-gtk
redshift-gtk
command -v redshift
redshift
EOF
	# Compositor
	cat << EOF > "$_configdir/compositor"
[ -z "\$DISPLAY" ]
:
command -v unagi
unagi
command -v compton
compton
command -v xcompmgr
xcompmgr
EOF
	# Polkit authentication agents
	cat << EOF > "$_configdir/polkit-agent"
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
EOF
	# Hotkey daemon
	cat << EOF > "$_configdir/hotkey-daemon"
[ -z "\$DISPLAY" ]
:
command -v sxhkd
sxhkd
EOF
	# Network daemon
	cat << EOF > "$_configdir/network-daemon"
command -v nm-applet
nm-applet
EOF
	# Notification daemon
	cat << EOF > "$_configdir/notification-daemon"
[ -z "\$DISPLAY" ]
:
command -v dunst
dunst
command -v lxqt-notificationd
notificationd
EOF
	# Power daemons
	cat << EOF > "$_configdir/power-daemon"
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
command -v gnome-power-manager
gnome-power-manager
EOF
	# Runners
	# Note that rofi is not a daemon and is not included here
	cat << EOF > "$_configdir/runner"
command -v krunner
krunner
EOF
	# Settings daemons
	cat << EOF > "$_configdir/settings-daemon"
command -v xsettingsd
xsettingsd
command -v xsettings-kde
xsettingskde
command -v xfsettingsd
xfsettingsd
command -v mate-settings-daemon
mate-settings-daemon
command -v gnome-settings-daemon
gnome-settings-daemon
EOF
	# System statistics glances
	# 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
	cat << EOF > "$_configdir/stat-glances"
[ -z "\$DISPLAY" ]
:
command -v conky && [ -r "\${XDG_CONFIG_HOME:-$HOME/.config}/conky/conky.conf" ]
sleep 5 && conky
EOF
	# Wallpaper setters
	cat << EOF > "$_configdir/wallpaper"
[ -z "\$DISPLAY" ]
:
command -v feh && [ -r "$HOME/.fehbg" ]
~/.fehbg
command -v nitrogen
nitrogen --restore
EOF
	# Window managers
	cat << EOF > "$_configdir/wm"
[ -z "\$DISPLAY" ]
:
command -v 2bwm
2bwm
command -v aewm
aewm
command -v awesome
awesome
command -v bspwm
bspwm
command -v catwm
catwm
command -v cwm
cwm
command -v dwm
dwm
command -v evilwm
evilwm
command -v exwm
exwm
command -v fluxbox
fluxbox
command -v flwm
flwm
command -v fvwm
fvwm
command -v herbstluftwm
herbstluftwm
command -v i3
i3
command -v icewm
icewm
command -v jbwm
jbwm
command -v jwm
jwm
command -v lwm
lwm
command -v openbox
openbox
command -v pawm
pawm
command -v ratpoison
ratpoison
command -v twm
twm
command -v windowmaker
windowmaker
command -v wmii
wmii
command -v xmonad
xmonad
command -v xfwm4
xfwm4
command -v metacity
metacity
command -v mutter
mutter
command -v kwin
kwin
command -v tinywm
tinywm
EOF
	# XDG autostarter
	cat << EOF > "$_configdir/xdg-autostart"
command -v dex
dex -a
command -v fbautostart
fbautostart
command -v xdg-autostart
xdg-autostart "\${XDG_CURRENT_DESKTOP:-firestarter}"
EOF
}
step_printhelp() {
	cat << EOF
Usage: $(basename -- "$0") [OPTION...]
Start or generate a desktop environment configuration

  -h		Show this help text
  -g		Generate a default configuration. This will clobber
  -d		Perform a dry run. This will print the results of all decisions
		without executing them.

Additionally, firestarter responds to the following environment variables:

  FS_NOLOG	If nonempty, create no log files

Copyright (c) 2019 rehashedsalt@cock.li
Licensed under the MIT License
https://gitlab.com/rehashedsalt/firestarter
EOF
}
step_check() {
	if [ -z "$_dryrun" ]; 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/$pid/sessionid")" ] && continue
			if [ "$pid" != "$BASHPID" ]; then
				err "Firestarter is already running: $pid" 40
			fi
		done
	fi
	if ! [ -d "$HOME" ] || ! [ -r "$HOME" ]; then
		err "Inaccessible home directory: \"$HOME\"" 54
	fi
	return 0
}
step_preexecute() {
	# Special things that can't use simple configuration files
	[ "$_dryrun" = "1" ] && return 0

	# 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 "$DBUS_SESSION_BUS_ADDRESS" ] && \
		command -v dbus-launch > /dev/null 2>&1; then
		# We have dbus but haven't started up a bus yet
		eval "$(dbus-launch --exit-with-session --sh-syntax)"
		hasdbus=1
	else
		log "Did not start dbus; some applications may misbehave"
	fi
	if [ -n "$hasdbus" ]; then
		if command -v dbus-update-activation-environment > /dev/null 2>&1; then
			dbus-update-activation-environment --verbose --systemd --all > /dev/null 2>&1
		fi
	fi
	unset hasdbus

	# kcminit/Qt settings
	if command -v kcminit > /dev/null 2>&1; then
		log "Initializing KDE Control Module settings"
		kcminit > /dev/null 2>&1
	elif command -v qt5ct > /dev/null 2>&1; then
		log "Integrating qt5ct"
		if [ -z "$QT_QPA_PLATFORMTHEME" ]; then
			export QT_QPA_PLATFORMTHEME="qt5ct"
			log "Exporting QT_QPA_PLATFORMTHEME as \"$QT_QPA_PLATFORMTHEME\""
		else
			log "Using existing theme setting \"$QT_QPA_PLATFORMTHEME\""
		fi
		if [ -z "$QT_AUTO_SCREEN_SCALE_FACTOR" ]; then
			export QT_AUTO_SCREEN_SCALE_FACTOR="0"
			log "Exporting QT_AUTO_SCREEN_SCALE_FACTOR as $QT_AUTO_SCREEN_SCALE_FACTOR"
		else
			log "Using existing scale setting \"$QT_AUTO_SCREEN_SCALE_FACTOR\""
		fi
	fi

	# xhost
	if command -v xhost > /dev/null 2>&1; then
		if xhost +si:localuser:"$(id -un)" > /dev/null 2>&1; then
			log "Session can be accessed in other sessions by this user"
		else
			log "Failed to open session up via xhost"
		fi
	fi

	# xresources
	if [ -n "$DISPLAY" ] && command -v xrdb && [ -r "$HOME/.Xresources" ]; then
		if xrdb "$HOME/.Xresources" > /dev/null 2>&1; then
			log "Loaded in .Xresources"
		else
			log "Failed to load .Xresources"
		fi
	fi

	# xset
	if command -v xset > /dev/null 2>&1; then
		log "Disabling bell"
		xset -b
	fi
}
step_execute() {
	# Ensure we have a config directory
	if ! [ -d "$_configdir" ]; then
		if ! mkdir -p "$_configdir" > /dev/null 2>&1; then
			err "Failed to create configuration directory: \"$_configdir\"" 52
		fi
	fi
	# Ensure we can log if we have to
	if [ -n "$FS_NOLOG" ]; then
		log "No logs will be created per FS_NOLOG"
	elif ! [ -d "$_logdir" ]; then
		if ! mkdir -p "$_logdir" > /dev/null 2>&1; then
			err "Failed to create log directory: \"$_logdir\"" 53
		fi
	fi
	# Parse configs
	for file in "$_configdir"/*; do
		if ! [ -f "$file" ]; then
			log "No configuration files found; generating defaults"
			step_generate
			step_execute
			break
		fi
		local filename="$(basename -- "$file")"
		local logfile="$_logdir/$filename"
		[ -n "$FS_NOLOG" ] && logfile="/dev/null"
		# Every odd line is the check line
		# Every even one is the exec line
		while read -r checkline; do
			read -r execline
			if bash -c "$checkline" > /dev/null 2>&1; then
				log "Found target for \"$filename\": \"$execline\""
				if ! [ "$_dryrun" = "1" ]; then
					if [ -f "$logfile" ]; then
						[ -f "$logfile.old" ] && rm "$logfile.old"
						mv "$logfile" "$logfile.old"
					fi
					bash -c "$execline" > "$logfile" 2>&1 &
				fi
				break
			else
				continue
			fi
		done < "$file"
	done
	# And then source in a user script if it exists
	if [ -r "$_firestarterrc" ] && [ -z "$_dryrun" ]; then
		log "Sourcing .firestarterrc"
		"$_firestarterrc"
	fi
}
step_wait() {
	[ "$_dryrun" = "1" ] && exit 0
	log "Waiting for programs to exit"
	log "Send any termination signal to firestarter to log out"
	trap step_logout EXIT
	wait
	exit 0
}
step_logout() {
	log "Logging out"
	if command -v loginctl > /dev/null 2>&1; then
		# Use loginctl if possible
		if [ -n "$_sessionid" ]; then
			loginctl terminate-session "$_sessionid"
		fi
	else
		# Otherwise just brute it
		kill $(jobs -p)
	fi
	return 0
}

# Main
main() {
	while getopts ":dgh" opt; do
		case $opt in
			d)
				if ! [ "$_dryrun" = "1" ]; then
					log "Performing a dry run"
					_dryrun=1
				fi
				;;
			g)
				step_generate
				exit $?
				;;
			h)
				step_printhelp
				exit $?
				;;
			*)
				err "Unrecognized argument: \"$OPTARG\"" 50
				;;
			:)
				err "Invalid option: \"$OPTARG\"" 51
				;;
		esac
	done
	step_check
	step_preexecute
	step_execute
	step_wait
	return 0
}

main "$@"