samba_kcc: avoid crash on odd networks with --dot-file-dir

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Garming Sam <garming@catalyst.net.nz>

diff --git a/python/samba/kcc/graph_utils.py b/python/samba/kcc/graph_utils.py
index 704f70d08e92671863ef585ff25a1f88d79ce172..e32695236245a9ead669eb5cca197b02fff58531 100644 (file)
--- a/python/samba/kcc/graph_utils.py
+++ b/python/samba/kcc/graph_utils.py
@@ -49,6 +49,10 @@ def write_dot_file(basename, edge_list, vertices=None, label=None,
 
     for i, edge in enumerate(edge_list):
         a, b = edge
+        if a is None:
+            a = "Missing source value"
+        if b is None:
+            b = "Missing destination value"
         if reformat_labels:
             a = a.replace(',', '\\n')
             b = b.replace(',', '\\n')