feat: Improve entrypoint (#1105)

trap - ERR

version=$(qemu-system-x86_64 --version | head -n 1 | cut -d '(' -f 1 | awk '{ print $NF }')

cmd=(qemu-system-x86_64)

version=$("${cmd[@]}" --version | awk 'NR==1 { print $4 }')

info "Booting image${BOOT_DESC} using QEMU v$version..."

[[ "$SHUTDOWN" != [Yy1]* ]] && exec qemu-system-x86_64 ${ARGS:+ $ARGS}

if [[ "$SHUTDOWN" != [Yy1]* ]]; then

  exec "${cmd[@]}" ${ARGS:+ $ARGS}

fi

if [ ! -t 1 ] || [ ! -c /dev/tty ]; then

  qemu-system-x86_64 ${ARGS:+ $ARGS} &

  "${cmd[@]}" ${ARGS:+ $ARGS} &

else

  qemu-system-x86_64 ${ARGS:+ $ARGS} </dev/tty >/dev/tty &

  "${cmd[@]}" ${ARGS:+ $ARGS} </dev/tty >/dev/tty &

fi

rc=0