#!/bin/sh

#echo "WORK INPROGRESS" && exit 0
BIN_DIR=/afs/csail.mit.edu/@sys/local/bin
KINIT=`which kinit`
AKLOG=`which aklog`
AUTHLOOP=$BIN_DIR/authloop
KRB5CCNAME=/tmp/krb5cc_$$.longjob
OUTFILE=/tmp/$USER.job.$$
RENEW="-r 8d"
AUTHOUT=/tmp/$USER.auth.$$
help()
{

cat <<EOF
$0 [options] <command> [command args]:

obtains and renews Kerberos tickets and AFS tokens for long running
job <command> the current limit on renewal is 8 days.  $0 runs the
specified <command> in the background using nohup.

NOTICE: if your account was created prior to May 1, 2004 contact 
help@csail.mit.edu to make sure you are able to obtain renewable 
Kerberos tickets.

Options:

-h|--help                    this help
-a|--auth-out <file>         output file for authentication loop
                             (default /tmp/$USER.auth.\$\$)
-c|--cache <krb5 cache file> cache file to use 
                             (default /tmp/krb5cc_\$\$.longjob)
-k|--keytab <keytab>         use <keytab> for authentication 
                             (default none uses password)
-o|--out-file <output file>  where to write output 
                             (default /tmp/$USER.job.\$\$)
-r|--renew <time spec>       renew for <time spec> 
                             (default and max 8d)


EOF

}

parse_opts ()
{
    while true ; do
        case "$1" in

	    '') 
		break
		;;
	    -h | --help) 
		help
		exit 0 
		;;
	    -a | --auth-out)
		export AUTHOUT=$2
		shift 2
		;;
	    -k | --keytab) 
		export KEYTAB="-k -t $2"
		export KRB5CCNAME=`mktemp -t krb5cc-longjob.XXXXXX`
		shift 2 
		;;
	    -o | --out-file) 
		export OUTFILE=$2 
		shift 2 
		;;
	    -r | --renew)
		export RENEW="-r $2"
		shift 2
		;;
	    -c | --cache)
		export KRB5CCNAME=$2
		shift 2
		;;
	    *) 
		export COMMAND="$COMMAND $1"
		shift
		;;

        esac
    done
}

run_command()
{
    echo "Output redirected to $OUTFILE"
    echo "PWD:        " $PWD >> $OUTFILE
    echo "KRB5CCNAME: " $KRB5CCNAME >> $OUTFILE
    echo "Command:    " $COMMAND >> $OUTFILE
    echo >> $OUTFILE
    nohup $COMMAND >> $OUTFILE 2>&1 &
}


parse_opts $@

if [ -z "$COMMAND" ]; then
    help
    echo "ERROR NO COMMAND GIVEN!"
    exit 1
fi

$KINIT $KEYTAB $RENEW
$AKLOG -setpag
nohup $AUTHLOOP $KEYTAB >> $AUTHOUT &
run_command