Fix mandatory locking

* lib/manlock.c (mailbox_open_and_lock): Force proper locker if
a null locker is associated with the mailbox.

1 files changed, 13 insertions, 0 deletions

diff --git a/lib/manlock.c b/lib/manlock.c
index 4a3b2be67..392c58155 100644
--- a/lib/manlock.c
+++ b/lib/manlock.c
@@ -126,6 +126,19 @@ mailbox_open_and_lock (mu_mailbox_t mbox, int flags)
       return MU_ERR_FAILURE;
     }
 
+  if (lock)
+    {
+      status = mu_locker_get_flags (lock, &flags);
+      if (status)
+        {
+          mu_diag_funcall (MU_DIAG_ERROR, "mu_locker_get_flags", urlstr,
+                           status);
+          return MU_ERR_FAILURE;
+        }
+      if (flags & MU_LOCKER_NULL)
+        lock = NULL;
+    }
+  
   if (!lock && manlock_mandatory_locking && manlock_lock_dir)
     {
       char *fname = NULL;