sd-netlink: don't treat NULL as root type-system

Explicitly export the root type-system to the type-system callers. This
avoids treating NULL as root, which for one really looks backwards (NULL
is usually a leaf, not root), and secondly prevents us from properly
debugging calling into non-nested types.

Also rename the root to "type_system_root". Once we support more than
rtnl, well will have to revisit that, anyway.

1 files changed, 2 insertions, 5 deletions

diff --git a/src/libsystemd/sd-netlink/netlink-types.c b/src/libsystemd/sd-netlink/netlink-types.c
index d22194ad71..40548dcbc0 100644
--- a/src/libsystemd/sd-netlink/netlink-types.c
+++ b/src/libsystemd/sd-netlink/netlink-types.c
@@ -476,7 +476,7 @@ static const NLType rtnl_types[RTM_MAX + 1] = {
         [RTM_GETNEIGH] = { .type = NETLINK_TYPE_NESTED, .type_system = &rtnl_neigh_type_system, .size = sizeof(struct ndmsg) },
 };
 
-const NLTypeSystem rtnl_type_system = {
+const NLTypeSystem type_system_root = {
         .count = ELEMENTSOF(rtnl_types),
         .types = rtnl_types,
 };
@@ -518,10 +518,7 @@ int type_system_get_type(const NLTypeSystem *type_system, const NLType **ret, ui
         const NLType *nl_type;
 
         assert(ret);
-
-        if (!type_system)
-                type_system = &rtnl_type_system;
-
+        assert(type_system);
         assert(type_system->types);
 
         if (type >= type_system->count)