[Libguestfs] [PATCH] lua: improve handle closing

[Pino Toscano]

Swap guestfs_close and free_per_handle_table, so first the handle is
removed from the table and then freed. This avoids passing a stale
pointer to free_per_handle_table (which right now is not an issue, but
better make sure it is never so).
---
Maybe this could also fix the case described by the comment there,
as when a new 'g' with the address of an old 'g' would be created,
the old 'g' is now already gone from the per-handle table.

 generator/lua.ml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/generator/lua.ml b/generator/lua.ml
index 5d5619c..fa6e9f2 100644
--- a/generator/lua.ml
+++ b/generator/lua.ml
@@ -168,13 +168,13 @@ guestfs_lua_create (lua_State *L)
 static void
 close_handle (lua_State *L, guestfs_h *g)
 {
-  guestfs_close (g);
   /* There is a potential and hard-to-solve race here: If another
    * thread allocates another 'g' at the same address, then
    * get_per_handle_table might be called with the same address
    * before we call free_per_handle_table here.  XXX
    */
   free_per_handle_table (L, g);
+  guestfs_close (g);
 }
 
 /* Finalizer. */
-- 
1.9.3