From 1ecd80ad606927ed8b3b5a1725427d26fc4b5d94 Mon Sep 17 00:00:00 2001
From: Carl Smith <carl.smith@alliedtelesis.co.nz>
Date: Wed, 9 Oct 2024 16:13:13 +1300
Subject: [PATCH] Prevent deletion of RO leaf-lists

The checks that were in the leaf processing code need
to also be in the leaf-list section. That is to check the
access (rw) and also if the leaves are hidden.
If the leaf-list is ro and the user has asked to delete
config-only then we also need to remove the leaves of the
leaf-list from the tree otherwise we end up with a strange
tree with what looks like values on the leaf-list list node.
---
 models/test.xml |  3 +++
 schema.c        | 36 ++++++++++++++++++++++++++++++++----
 2 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/models/test.xml b/models/test.xml
index 5836b02..dc42e1e 100644
--- a/models/test.xml
+++ b/models/test.xml
@@ -86,6 +86,9 @@
         <NODE name="minutes" mode="r" help="minutes" range="0..59"/>
         <NODE name="seconds" mode="r" help="seconds" range="0..59"/>
       </NODE>
+      <NODE name="romembers" help="A read-only leaf-list">
+        <NODE name="*" mode="r" help="Member of group"/>
+      </NODE>
     </NODE>
     <NODE name="animals">
       <NODE name="animal" help="This is a list of animals">
diff --git a/schema.c b/schema.c
index c9dd81b..b9217d2 100644
--- a/schema.c
+++ b/schema.c
@@ -3301,6 +3301,7 @@ _sch_traverse_nodes (sch_instance * instance, sch_node * schema, GNode * parent,
                     free ((void *)child->children->data);
                     free ((void *)child->data);
                     g_node_destroy (child);
+                    child = NULL;
                 }
                 else if (!sch_is_writable (schema))
                 {
@@ -3369,8 +3370,10 @@ _sch_traverse_nodes (sch_instance * instance, sch_node * schema, GNode * parent,
     }
     else if (g_strcmp0 (name, "*") == 0)
     {
-        for (GNode *child = parent->children; child; child = child->next)
+        child = parent->children;
+        while (child)
         {
+            GNode *next = child->next;
             for (sch_node *s = sch_node_child_first (schema); s; s = sch_node_next_sibling (s))
             {
                 if (flags & SCH_F_FILTER_RDEPTH)
@@ -3384,6 +3387,13 @@ _sch_traverse_nodes (sch_instance * instance, sch_node * schema, GNode * parent,
                 if (!rc)
                     goto exit;
             }
+            if (!child->children)
+            {
+                DEBUG (flags, "Throwing away node \"%s\"\n", APTERYX_NAME (child));
+                free ((void *)child->data);
+                g_node_destroy (child);
+            }
+            child = next;
         }
     }
     else if (sch_is_leaf_list (schema))
@@ -3392,10 +3402,28 @@ _sch_traverse_nodes (sch_instance * instance, sch_node * schema, GNode * parent,
         {
             if (!(flags & SCH_F_FILTER_RDEPTH) || (depth >= rdepth))
             {
-                for (GNode *leaf = child->children; leaf; leaf = leaf->next)
+                /* Access is stored on the * node */
+                sch_node *lschema = sch_node_child_first (schema);
+                if (sch_is_hidden (lschema) ||
+                   (flags & SCH_F_CONFIG && !sch_is_writable (lschema)))
                 {
-                    free (leaf->children->data);
-                    leaf->children->data = g_strdup ("");
+                    DEBUG (flags, "Silently ignoring leaf-list \"%s\"\n", name);
+                    apteryx_free_tree (child);
+                    child = NULL;
+                }
+                else if (!sch_is_writable (lschema))
+                {
+                    ERROR (flags, SCH_E_NOTWRITABLE, "Node not writable \"%s\"\n", name);
+                    rc = false;
+                    goto exit;
+                }
+                else
+                {
+                    for (GNode *leaf = child->children; leaf; leaf = leaf->next)
+                    {
+                        free (leaf->children->data);
+                        leaf->children->data = g_strdup ("");
+                    }
                 }
             }
         }