install_prereq: fix macos

common/installer.sh

@@ -654,3 +654,31 @@ check_prerequisites_openwrt()
 		fi
 	}
 }
+
+
+
+select_ipv6()
+{
+	local T=N
+
+	[ "$DISABLE_IPV6" != '1' ] && T=Y
+	local old6=$DISABLE_IPV6
+	echo
+	if ask_yes_no $T "enable ipv6 support"; then
+		DISABLE_IPV6=0
+	else
+		DISABLE_IPV6=1
+	fi
+	[ "$old6" != "$DISABLE_IPV6" ] && write_config_var DISABLE_IPV6
+}
+select_fwtype()
+{
+	echo
+	[ $(get_ram_mb) -le 400 ] && {
+		echo WARNING ! you are running a low RAM system
+		echo WARNING ! nft requires lots of RAM to load huge ip sets, much more than ipsets require
+		echo WARNING ! if you need large lists it may be necessary to fall back to iptables+ipset firewall
+	}
+	echo select firewall type :
+	ask_list FWTYPE "iptables nftables" "$FWTYPE" && write_config_var FWTYPE
+}