function requiredir {
 [ -n "$1" ] || exit 1
 [ -e $1 ] || mkdir $1
}

function err {
 echo $1
 exit 1
}

function checkstage {
 [ -e ${WORKDIR}/stage/_$1 ] || return 1
 [ "$(cat $WORKDIR/stage/_$1)" != "done" ] && return 2
 return 0
}

function startstage {
 echo -n "started" > ${WORKDIR}/stage/_$1
}
function endstage {
 echo -n "done" > ${WORKDIR}/stage/_$1
}