#!/bin/sh

case "$1" in -h|-H|-help|--help)
	cat <<EOT
Usage: ${0##*/} [-shared]
       -shared  also attempt to build a shared library
Env:   CC       explicit "cc" compiler to use
       AR       explicit "ar" to use
       RANLIB   explicit "ranlib" to use
       CFLAGS   explicit compiler options to use
       FPIC     explicit -fPIC/-fpic (or none) option to use
EOT
	exit 0
esac

set -e

LIB=libBlocksRuntime.a
SRC=BlocksRuntime

shared=
[ z"$1" != z"-shared" -a z"$1" != z"--shared" ] || shared=1

if [ -n "$shared" ]; then
	UNAME_S="$(uname -s 2>/dev/null)" || :
	case "$UNAME_S" in
		Darwin)
			SHLIB="${LIB%.a}.dylib"
			SHOPT="-dynamiclib -Wl,-all_load"
			SHOPT2=
			;;
		*)
			SHLIB="${LIB%.a}.so"
			SHOPT="-shared -Wl,-whole-archive"
			SHOPT2="-Wl,-no-whole-archive"
			;;
	esac
fi

if [ -z "$CC" ]; then
	if command -v gcc > /dev/null; then
		CC=gcc
	elif command -v clang > /dev/null; then
		CC=clang
	elif command -v cc > /dev/null; then
		CC=cc
	else
		echo "Could not guess name of compiler, please set CC" >&2
		exit 2
	fi
fi

echo "CC=$CC"
: ${AR:=ar}
echo "AR=$AR"
: ${RANLIB:=ranlib}
echo "RANLIB=$RANLIB"

if [ "${CFLAGS+set}" != "set" ]; then
	case "$CC" in
		*gcc*|*clang*)
			CFLAGS=-O2
			;;
		*)
			CFLAGS=-O
			;;
	esac
fi

has_cc_opt()
{
	"$CC" "$1" -o /tmp/cc.$$ -c -x c /dev/null >/dev/null 2>&1 &&
	rm -f /tmp/cc.$$
}
if [ "${FPIC+set}" != "set" ]; then
	if has_cc_opt "-fPIC"; then
		FPIC="-fPIC"
	elif has_cc_opt "-fpic"; then
		FPIC="-fpic"
	fi
fi
[ -z "$FPIC" ] || echo "FPIC=$FPIC"

echo "CFLAGS=$CFLAGS"

echo "LIB=$LIB"
[ -z "$shared" ] || echo "SHLIB=$SHLIB"
[ -z "$shared" ] || echo "SHOPT=$SHOPT"
[ -z "$shared" ] || [ -z "$SHOPT2" ] || echo "SHOPT2=$SHOPT2"
echo "SRC=$SRC"

(
	PS4= && set -ex
	! test -e $LIB || rm $LIB
) || exit
[ -z "$shared" ] ||
(
	PS4= && set -ex
	! test -e $SHLIB || rm $SHLIB
) || exit
(
	PS4= && set -ex
	"$CC" -c $FPIC $CFLAGS -o $SRC/data.o $SRC/data.c &&
	"$CC" -c $FPIC $CFLAGS -o $SRC/runtime.o -I . $SRC/runtime.c &&
	"$AR" cr $LIB $SRC/data.o $SRC/runtime.o &&
	"$RANLIB" $LIB
) || exit
[ -z "$shared" ] ||
(
	PS4= && set -ex
	"$CC" $FPIC $CFLAGS -o "$SHLIB" $SHOPT $LIB $SHOPT2
) || exit