#!/bin/bash

if [ $# -lt 2 ]; then
    echo "Usage: $0 [name] [script]"
    exit 1;
fi

NAME=$1
SCRIPT=$2

LOCKDIR="/var/tmp/$NAME"
PIDFILE="$LOCKDIR/pid"

function cleanup {
    rm -rf "$LOCKDIR"
}

RESTORE_UMASK=$(umask -p)
umask 0077
if ! mkdir "$LOCKDIR"; then
    echo "$LOCKDIR already exists"
    PID=$(cat "$PIDFILE")
    if [ -n "$PID" ] && /bin/ps $PID > /dev/null
    then
        exit 1;
    else
        echo "$LOCKDIR exists but $PID is dead"
        echo "Removing lockdir and re-running"
        /bin/rm -rf $LOCKDIR
        mkdir $LOCKDIR || exit
    fi
fi

trap cleanup EXIT SIGQUIT SIGHUP SIGTERM
echo $$ > "$PIDFILE"

$RESTORE_UMASK
eval "$SCRIPT"