#!/bin/bash
# Makes sure there's only one copy of krenew running at any given time for 
# a file in /tmp/krb5cc_* . Can then be referenced in an alias efficiently.

DATE=`date '+%Y-%m-%d %H:%M:%S'`
FILE="/tmp/krb5cc_$1"
PIDFILE="${FILE}.pid"
LOGFILE="${FILE}.log"
KRENEW_ARGS="-K 10 -t -v -p ${PIDFILE}"

if [ "x$1" == "x" ] ; then
    echo "Usage: $0 USER"
    exit 0
fi

if [ ! -f ${FILE} ] ; then
    if [ ! "$PLATFORM" = "macosx" ]; then
        echo "No ticket cache to work with: ${FILE}"
        exit 0
    fi
fi

touch ${LOGFILE}

if [ ! -f ${PIDFILE} ] ; then
    echo "${DATE} Starting new krenew" | tee -a ${LOGFILE}
    touch ${LOGFILE}
    krenew ${KRENEW_ARGS} >> ${LOGFILE} 2>&1 &
else
    PID=`cat ${PIDFILE}`
    if kill -0 ${PID}  2>/dev/null; then
        echo "${DATE} Already running (pid ${PID})" | tee -a ${LOGFILE}
    else
        echo "${DATE} Restarting krenew" | tee -a ${LOGFILE}
        krenew ${KRENEW_ARGS} >> ${LOGFILE} 2>&1 &
    fi
fi