build/distfiles: clean up subdiretories on manual arguments passed

This eases maintenance when trying to refetch smaller portions of
distfiles without losing the others.

build/common.sh

@@ -641,6 +641,16 @@ setup_distfiles()
 		mkdir -p ${1}${PORTSDIR}
 		rm -rf ${1}${PORTSDIR}/distfiles
 		tar -C ${1}${PORTSDIR} -xpf ${DISTFILESET}
+
+		# clear all additional sub-directories passed
+		for DIR in ${@}; do
+			rm -rf ${1}${PORTSDIR}/distfiles/${DIR}
+		done
+	fi
+
+	if [ -n "${@}" ]; then
+		# in cleanup mode signal that we are done
+		return 1
 	fi
 }
 

build/distfiles.sh

@@ -42,7 +42,15 @@ setup_base ${STAGEDIR}
 setup_clone ${STAGEDIR} ${PORTSDIR}
 setup_clone ${STAGEDIR} ${SRCDIR}
 setup_chroot ${STAGEDIR}
-setup_distfiles ${STAGEDIR}
+
+if ! setup_distfiles ${STAGEDIR} ${@}; then
+	echo -n ">>> Recreating distfiles set... "
+	tar -C ${STAGEDIR}${PORTSDIR} -cf \
+	    ${SETSDIR}/distfiles-${PRODUCT_VERSION}.tar distfiles
+	echo "done"
+
+	exit 0
+fi
 
 extract_packages ${STAGEDIR} || true