BeOS/ar-fake

#! /bin/sh
#
# Fake "ar" to build the Python shared library on BeOS.  This "ar"
# manipulates a .ar-libname file listing all the objects and regenerates
# the shared lib every time it's called.  This is probably only suitable
# for things that get built like Python, and you'll probably have to make
# some small modifications here and there.
#
# This stupid hackery is necessary due to the brain-damaged __declspec()
# semantics on x86; on PowerPC, we could just build a static library
# and turn that into a shared library using an exports list.  On x86, you'd
# need to use a fake table of pointers to every symbol you wanted to
# export, otherwise you'd end up with an empty shared lib.  This is
# progress?
#
# Called via:
#
# ar-fake cr lib-name objects
# ar-fake d lib-name objects
#
# This fake "ar" DOES NOT support any other POSIX "ar" commands!  DO NOT
# expect it to behave very intelligently, it's designed to build Python,
# not any old shared lib.

AR_COMMAND=$1 ; shift
AR_LIB=$1 ; shift
AR_LIB_NAME=$(basename $AR_LIB)
AR_SO_LIB_NAME=${AR_LIB_NAME/.a/.so}
AR_LIB_PATH=${AR_LIB/$AR_LIB_NAME/}
if [ "$AR_LIB_PATH" = "" ] ; then
	AR_LIB_PATH="."
fi
AR_CRUD=${AR_LIB_PATH}/.ar-${AR_LIB_NAME}

AR_CWD=$(pwd)

# Function to tell is if the arg is an absolute path.  Use it like this:
#
# if is_abs pathname ; then ...
is_abs() {
	if [ "$1" != "$(echo $1 | sed -e "s,^/,,")" ] ; then
		return 0
	fi
	return 1
}

# Function to build the shared library.  It does the right thing for
# PowerPC or x86 systems running BeOS.
build_lib() {
	LIB=$1 ; shift
	SO_LIB=${LIB/.a/.so}
	SO_NAME=$1 ; shift
	CRUD_NAME=$1 ; shift

	# maybe too much...	
	EXTRA_LIBS="-lroot -lbe -lnet"

	case $BE_HOST_CPU in
		ppc)
			case $(uname -r) in
				4.0*) AR_CC="mwcc -xms -export pragma -nodup" ;;
				*) AR_CC="mwcc -shared -export pragma -nodup" ;;
			esac
			GLUE_LOC=/boot/develop/lib/ppc
			AR_GLUE="${GLUE_LOC}/glue-noinit.a ${GLUE_LOC}/init_term_dyn.o ${GLUE_LOC}/start_dyn.o"
			;;

		x86)
			AR_CC="gcc -nostart -Wl,-soname=${SO_NAME}"
			AR_GLUE=
			;;

		*)
			# Send me the mystery system (soo-pah aitch!), then we'll talk...
			echo "No, no, no... $0 doesn't support $BE_HOST_CPU"
			exit 2
			;;
	esac

	# Build a list of the objects...
	PARTS=""
	while read OBJ_FILE OBJ_PATH ; do
		PARTS="$PARTS ${OBJ_PATH}${OBJ_FILE}"
	done < $CRUD_NAME

	$AR_CC -o $SO_LIB $PARTS $AR_GLUE $EXTRA_LIBS > /dev/null 2>&1

	return 0
}

# Make a backup of the old AR_CRUD file, just to be nice, and clean up
# any of our temp files that may be laying around.
if [ -e $AR_CRUD ] ; then
	mv -f $AR_CRUD ${AR_CRUD}.old
	cp ${AR_CRUD}.old $AR_CRUD
else
	touch $AR_CRUD
fi

if [ -e ${AR_CRUD}.grepper ] ; then
	rm -f ${AR_CRUD}.grepper
fi

case $AR_COMMAND in
	cr)
		# Add the extra bits to the $AR_CRUD file.
		for OBJECT in "$@" ; do
			OBJ_NAME=$(basename $OBJECT)
			OBJ_PATH=${OBJECT%$OBJ_NAME}
			if ! is_abs $OBJ_PATH ; then
				OBJ_PATH=${AR_CWD}/${OBJECT}
				OBJ_PATH=${OBJ_PATH%$OBJ_NAME}
			fi
			
			# If this is already in there, we have to blow it away so
			# we can replace it with the new one.
			if egrep -q "^$OBJ_NAME " $AR_CRUD ; then
				egrep -v "^$OBJ_NAME " < $AR_CRUD > ${AR_CRUD}.grepper
				mv -f ${AR_CRUD}.grepper $AR_CRUD
			fi

			echo $OBJ_NAME $OBJ_PATH >> $AR_CRUD
		done
		
		# Now build a library from the files.
		build_lib $AR_LIB $AR_SO_LIB_NAME $AR_CRUD
		;;

	d)
		# Remove files from the $AR_CRUD file.  This isn't terribly
		# efficient.
		for OBJECT in "$@" ; do
			OBJ_NAME=$(basename $OBJECT)
			OBJ_PATH=${OBJECT%$OBJ_NAME}
			if ! is_abs $OBJ_PATH ; then
				OBJ_PATH=${AR_CWD}/${OBJECT}
				OBJ_PATH=${OBJ_PATH%$OBJ_NAME}
			fi

			# Strip the objects from the list, if they're in there.
			egrep -v "^$OBJ_NAME " < $AR_CRUD > ${AR_CRUD}.grepper
			mv -f ${AR_CRUD}.grepper $AR_CRUD
		done
			
		# Now build a library from the remaining objects.
		build_lib $AR_LIB $AR_SO_LIB_NAME $AR_CRUD
		;;

	*)
		echo "$0 error:"
		echo "	Unsupported command: $AR_COMMAND"
		exit 1
		;;
esac

# If we make it here, all went well.  Hopefully.
exit 0