warn earlier for missing nftables support

Change-Id: Ib19a3f671b096c349c13ed650837c621ac7ecd20
---
M src/osmo-hnbgw/hnbgw_vty.c
1 file changed, 16 insertions(+), 0 deletions(-)


git pull ssh://gerrit.osmocom.org:29418/osmo-hnbgw refs/changes/76/37076/1

diff --git a/src/osmo-hnbgw/hnbgw_vty.c b/src/osmo-hnbgw/hnbgw_vty.c
index d719c29..f20dbff 100644
--- a/src/osmo-hnbgw/hnbgw_vty.c
+++ b/src/osmo-hnbgw/hnbgw_vty.c
@@ -887,6 +887,7 @@
       NFT_KPI_STR
       "Set a custom nft table name to use, instead of 'osmo-hnbgw'\n")
 {
+#if ENABLE_NFTABLES
 	const char *set_table_name = NULL;
 	if (argc > 0)
 		set_table_name = argv[0];
@@ -898,12 +899,18 @@
 	osmo_talloc_replace_string(g_hnbgw, &g_hnbgw->config.nft_kpi.table_name, set_table_name);
 
 	return CMD_SUCCESS;
+#else
+	/* This VTY cmd is trying to enable nft-kpi, but this binary does not support nftables. Error immediately. */
+	vty_out(vty, "%% ERROR: Built without libnftables support, cannot enable nft-kpi%s", VTY_NEWLINE);
+	return CMD_WARNING;
+#endif
 }
 
 DEFUN(cfg_hnbgw_no_nft_kpi, cfg_hnbgw_no_nft_kpi_cmd,
 	"no nft-kpi",
 	NO_STR NFT_KPI_STR)
 {
+	/* This function has no #if ENABLE_NFTABLES: always allow to switch off nft-kpi. */
 	if (vty->type == VTY_TERM)
 		vty_out(vty, "%% WARNING: nft configuration changes need a restart of osmo-hnbgw%s", VTY_NEWLINE);
 	g_hnbgw->config.nft_kpi.enable = false;

