#!/bin/bash

 #

 # $Id$

 #

 # SML/NJ startup script (for 0.93).

 #

 # Global vars: INFILE OUTFILE MLTEXT TERMINATE NOWRITE ISABELLE_TMP,

 # and from settings

 ## diagnostics

 function fail_out()

 {

   echo "Unable to create output heap file: \"$OUTFILE\"" >&2

   exit 2

 }

 ## prepare databases

 if [ -z "$INFILE" ]; then

   INFILE="$ML_HOME/sml"

   EXIT="val exit: int -> unit = System.Unsafe.CInterface.exit;"

 else

   EXIT=""

 fi

 MOVE=""

 if [ -z "$OUTFILE" ]; then

   COMMIT='fun commit () = (output (std_err, "Error - Database is not opened for writing.\n"); false);'

 else

   if [ "$INFILE" -ef "$OUTFILE" ]; then

     OUTDIR=$(dirname "$OUTFILE")/tmp

     OUTFILE=$OUTDIR/$(basename "$OUTFILE")

     mkdir -p "$OUTDIR" || fail_out

     MOVE=true

   fi

   [ -f "$OUTFILE" ] && { chmod +w "$OUTFILE" || fail_out; }

   COMMIT="fun commit () = not (exportML\"$OUTFILE\");"

 fi

 ## run it!

 MLTEXT="$EXIT $COMMIT $MLTEXT"

 MLEXIT="commit();"

 if [ -z "$TERMINATE" ]; then

   FEEDER_OPTS=""

 else

   FEEDER_OPTS="-q"

 fi

 $ISABELLE_HOME/lib/scripts/feeder -p -h "$MLTEXT" -t "$MLEXIT" $FEEDER_OPTS | \

   { read FPID; $INFILE $ML_OPTIONS; RC=$?; kill -HUP $FPID; exit $RC; }

 RC=$?

 ## fix heap file

 [ -n "$OUTFILE" -a -f "$OUTFILE" -a -n "$NOWRITE" ] && chmod -w "$OUTFILE"

 if [ -n "$MOVE" -a -f "$OUTFILE" ]; then

   rm -f "$INFILE" || fail_out

   mv "$OUTFILE" "$INFILE" || fail_out

 fi

 exit $RC