#!/bin/sh

CMD=`basename "$0"`

usage() {
	echo "usage: $CMD [--linkwith-<format>] heapfile execfile"
	echo "       <format> = exec | so | a"
	exit 1
}

die () {
	echo "${CMD}: $1"
	exit 1
}

if [ x${SMLNJ_HOME} = x ] ; then
    BIN_DIR="/mnt/gmirror/ports/lang/sml-nj-devel/work/bin"
else
    BIN_DIR=${SMLNJ_HOME}/bin
fi

ARCH_N_OPSYS=`"$BIN_DIR/.arch-n-opsys"`
if [ "$?" != "0" ]; then
	die "unable to determine architecture/operating system"
fi
eval $ARCH_N_OPSYS

RUNX=${BIN_DIR}/.run/runx.${ARCH}-${OPSYS}
RUN_SO=${BIN_DIR}/.run/run.${ARCH}-${OPSYS}.so
RUN_A=${BIN_DIR}/.run/run.${ARCH}-${OPSYS}.a
H2A=${BIN_DIR}/heap2asm

FORMAT=
if [ $# != 2 ] ; then
	if [ $# = 3 ] ; then
		case $1 in
			--linkwith-exec)
				FORMAT=exec
				;;
			--linkwith-so)
				FORMAT=so
				;;
			--linkwith-a)
				FORMAT=a
				;;
			*)
				usage
				;;
		esac
		shift
   	else
		usage
	fi
else
	case ${OPSYS} in
		darwin)
			FORMAT=exec
			;;
		freebsd|linux)
			FORMAT=a
			;;
		*)
			die "no default runtime link format known for ${OPSYS}"
			;;
		esac
fi
if [ -z "$FORMAT" ] ; then
	die "no runtime object format specified"
fi

heapfile=$1
execfile=$2

CC=cc
LD=ld

EXEC_PROG=
EXEC_FLAGS=
EXEC_LIBS=
SO_PROG=
SO_FLAGS=
SO_LIBS=
A_PROG=
A_FLAGS=
A_LIBS=

case ${OPSYS} in
	darwin)
		EXEC_PROG=${LD}
		EXEC_LIBS=-lc
		;;
	freebsd)
		SO_PROG=${CC}
		SO_FLAGS=-Wl,--export-dynamic
		SO_LIBS=-lm
		A_PROG=${CC}
		A_FLAGS=-Wl,--export-dynamic
		A_LIBS=-lm
		;;
	linux)
		SO_PROG=${CC}
		SO_FLAGS=-Wl,--export-dynamic
		A_PROG=${CC}
		A_FLAGS=-Wl,--export-dynamic
		A_LIBS="-lm -ldl"
		;;
	*)
		;;
esac

if [ ! -f $H2A ]; then
	echo "${CMD}: heap2asm is not installed"
	exit 2
fi

RESULT=0
if ${H2A} "$heapfile" "$execfile".s ; then
	if [ -f "$execfile".s ] ; then
		if ${CC} -c -o "$execfile".o "$execfile".s ; then
			rm "$execfile".s
		else
			rm "$execfile".s
			die "${execfile}.o creation failed"
		fi
	else
		die "${execfile}.s creation failed"
	fi
	if [ "$FORMAT" = exec -a -f "${RUNX}" ] ; then
		[ -z "${EXEC_PROG}" ] && die "no linker specified for runtime format $FORMAT"
		${EXEC_PROG} ${EXEC_FLAGS} -o "$execfile" ${RUNX} "$execfile".o ${EXEC_LIBS}
		RESULT=$?
	elif [ "$FORMAT" = so -a -f "${RUN_SO}" ] ; then
		[ -z "${SO_PROG}" ] && die "no linker specified for runtime format $FORMAT"
		${SO_PROG} ${SO_FLAGS} -o "$execfile" ${RUN_SO} "$execfile".o ${SO_LIBS}
		RESULT=$?
	elif [ "$FORMAT" = a -a -f "${RUN_A}" ] ; then
		[ -z "${A_PROG}" ] && die "no linker specified for runtime format $FORMAT"
		${A_PROG} ${A_FLAGS} -o "$execfile" ${RUN_A} "$execfile".o ${A_LIBS}
		RESULT=$?
	else
		echo "${CMD}: linkable runtime system object ($FORMAT) not available"
		rm "$execfile".o
		exit 2
	fi
	rm "$execfile".o
else
	die "heap2asm failed"
fi

if [ $RESULT != 0 ] ; then
	die "linking failed with return code $RESULT"
fi

exit 0