#!/usr/bin/env bash

#

# Author: Markus Wenzel, TU Muenchen

#

# SML/NJ startup script (for 110 or later).

export -n INFILE OUTFILE COPYDB COMPRESS MLTEXT TERMINATE NOWRITE

## diagnostics

function fail_out()

{

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

  exit 2

}

function check_mlhome_file()

{

  if [ ! -f "$1" ]; then

    echo "Unable to locate $1" >&2

    echo "Please check your ML_HOME setting!" >&2

    exit 2

  fi

}

function check_heap_file()

{

  if [ ! -f "$1" ]; then

    echo "Expected to find ML heap file $1" >&2

    return 1

  else

    return 0

  fi

}

## compiler binaries

SML="$ML_HOME/sml"

ARCH_N_OPSYS="$ML_HOME/.arch-n-opsys"

check_mlhome_file "$SML"

check_mlhome_file "$ARCH_N_OPSYS"

## prepare databases

if [ -z "$INFILE" ]; then

  EXIT="fun exit 0 = (OS.Process.exit OS.Process.success): unit | exit _ = OS.Process.exit OS.Process.failure;"

  DB=""

else

  EXIT=""

  DB="@SMLload=$INFILE"

fi

if [ -z "$OUTFILE" ]; then

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

else

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

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

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; "$SML" $ML_OPTIONS "$DB"; RC="$?"; kill -HUP "$FPID"; exit "$RC"; }

RC="$?"

## fix heap file name and permissions

if [ -n "$OUTFILE" ]; then

  eval $("$ARCH_N_OPSYS")

  [ -z "$HEAP_SUFFIX" ] && HEAP_SUFFIX="$ARCH-$OPSYS"

  HEAP="$OUTFILE.$HEAP_SUFFIX"

  check_heap_file "$HEAP" && mv "$HEAP" "$OUTFILE" && \

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

fi

exit "$RC"