#!/bin/sh --
# sx - start an xserver

# requires xauth Xorg

cleanup() {
    if [ "$pid" ] && kill -0 "$pid" 2> /dev/null; then
        kill -s TERM "$pid"
        wait "$pid"
        r=$?
    fi

    if ! stty "$stty"; then
        stty sane
    fi

    xauth remove :"$tty"
    exit "${r:-$?}"
}

stty=$(stty -g)
tty=$(tty | cut -c 6-9)
#tty=$(ps -o tty= $$)
tty=${tty#tty}

cfgdir=${XDG_CONFIG_HOME:-$HOME/.config}/sx
datadir=${XDG_DATA_HOME:-$HOME/.local/share}/sx

mkdir -p "$cfgdir" "$datadir"

export XAUTHORITY=${XAUTHORITY:-$datadir/xauthority}
touch "$XAUTHORITY"

trap 'cleanup' EXIT
xauth add :"$tty" MIT-MAGIC-COOKIE-1 "$(od -An -N16 -tx /dev/urandom | tr -d ' ')"

# Xorg will check if its SIGUSR1 disposition is SIG_IGN and use this state to
# reply back to the parent process with its own SIGUSR1 as an indication it is
# ready to accept connections.
# Taking advantage of this feature allows us to launch our client directly
# from a SIGUSR1 handler and avoid the need to poll for server readiness.
trap 'DISPLAY=:$tty "${@:-$cfgdir/sxrc}"' USR1
(trap '' USR1 && exec Xorg :"$tty" -keeptty vt"$tty" -noreset -auth "$XAUTHORITY") & pid=$!
wait "$pid"