resolved: suppress ifindex info in varlink JSON responses if zero

poettering · poettering · commit f8f5b8d864d3 · 2021-02-06T00:17:10.000+01:00
If we don't have ifindex info, don't set the field for it. We already do that for parsed IP address replies, let's do it for all cases: it's a bit nicer to suppress the ifindex prop if it doesn't apply than to pass it invalid. This is the other side of systemd#18482, i.e. fixes things so that the parser doesn't get tripped up by this. (This too makes a problem go away we should track down properly, i.e. figure out how the ifindex got lost in systemd#17823 (comment) )
diff --git a/src/resolve/resolved-varlink.c b/src/resolve/resolved-varlink.c
@@ -180,7 +180,7 @@ static void vl_method_resolve_hostname_complete(DnsQuery *q) {
 
                 r = json_build(&entry,
                                JSON_BUILD_OBJECT(
-                                               JSON_BUILD_PAIR("ifindex", JSON_BUILD_INTEGER(ifindex)),
+                                               JSON_BUILD_PAIR_CONDITION(ifindex > 0, "ifindex", JSON_BUILD_INTEGER(ifindex)),
                                                JSON_BUILD_PAIR("family", JSON_BUILD_INTEGER(family)),
                                                JSON_BUILD_PAIR("address", JSON_BUILD_BYTE_ARRAY(p, FAMILY_ADDRESS_SIZE(family)))));
                 if (r < 0)
@@ -408,7 +408,7 @@ static void vl_method_resolve_address_complete(DnsQuery *q) {
 
                 r = json_build(&entry,
                                JSON_BUILD_OBJECT(
-                                               JSON_BUILD_PAIR("ifindex", JSON_BUILD_INTEGER(ifindex)),
+                                               JSON_BUILD_PAIR_CONDITION(ifindex > 0, "ifindex", JSON_BUILD_INTEGER(ifindex)),
                                                JSON_BUILD_PAIR("name", JSON_BUILD_STRING(normalized))));
                 if (r < 0)
                         goto finish;
