l3cfg: add nm_netns_get_l3cfg() accessor

This is more for debugging and testing. Usually you want to call
nm_netns_access_l3cfg() which creates a NML3Cfg instance, if necessary.

src/nm-netns.c

@@ -125,6 +125,19 @@ _l3cfg_weak_notify(gpointer data, GObject *where_the_object_was)
         g_object_unref(self);
 }
 
+NML3Cfg *
+nm_netns_get_l3cfg(NMNetns *self, int ifindex)
+{
+    NMNetnsPrivate *priv;
+
+    g_return_val_if_fail(NM_IS_NETNS(self), NULL);
+    g_return_val_if_fail(ifindex > 0, NULL);
+
+    priv = NM_NETNS_GET_PRIVATE(self);
+
+    return g_hash_table_lookup(priv->l3cfgs, &ifindex);
+}
+
 NML3Cfg *
 nm_netns_access_l3cfg(NMNetns *self, int ifindex)
 {

src/nm-netns.h

@@ -31,6 +31,8 @@ struct _NMDedupMultiIndex *nm_netns_get_multi_idx(NMNetns *self);
 
 #define NM_NETNS_GET (nm_netns_get())
 
+NML3Cfg *nm_netns_get_l3cfg(NMNetns *self, int ifindex);
+
 NML3Cfg *nm_netns_access_l3cfg(NMNetns *netns, int ifindex);
 
 /*****************************************************************************/