Fix for changing of prefix-list entries.

A bug in vector_move_item_here() meant that under some circumstances
an "ip prefix-list" command would trigger an assert() because updating
an existing entry (with a sequence number) failed to keep the cache
of entries correctly sorted.

1 files changed, 14 insertions, 3 deletions

diff --git a/lib/vector.c b/lib/vector.c
index 83f289fe..e03febdc 100644
--- a/lib/vector.c
+++ b/lib/vector.c
@@ -441,11 +441,13 @@ vector_move_item(vector v, vector_index i_dst, vector_index i_src)
  *
  *   rider <  0 -- move to before the item at the given position
  *   rider == 0 -- move to replace item at the given position
- *   rider >  0 -- insert after the item at the given position
+ *   rider >  0 -- move to after the item at the given position
  *
  * NB: it is the caller's responsibility to release the any existing value
  *     that will be replaced.
  *
+ * NB: replacing an item by itself (rider == 0, i_dst == i_src) deletes it !
+ *
  * Move items and extend vector as required.
  */
 void
@@ -454,8 +456,17 @@ vector_move_item_here(vector v, vector_index i_dst, int rider,
 {
   if (rider != 0)
     {
-      if (rider > 0)
-	++i_dst ;
+      if      (i_src < i_dst)
+        {
+          if (rider < 0)
+            --i_dst ;           /* moving up places src after dst       */
+        }
+      else if (i_src > i_dst)
+        {
+          if (rider > 0)
+            ++i_dst ;           /* moving down places src before dst    */
+        } ;
+
       vector_move_item(v, i_dst, i_src) ;
     }
   else