[gtk/wip/carlosg/selection-null-checks: 2/2] gdk/wayland: Harden against NULL selection content

[Carlos Garnacho <carlosg src gnome org>]

commit a097ca090650ab84584b734cc05bdaaae2d242cc
Author: Carlos Garnacho <carlosg gnome org>
Date:   Thu Feb 20 11:36:51 2020 +0100

    gdk/wayland: Harden against NULL selection content
    
    If NULL is returned, probably the client shouldn't advertise the
    mimetype. Make it sure we forget entirely about the attempt to
    cache this mimetype, as it'll be mistaken as pending otherwise.
    
    Dropping this cached selection will in consequence close the fd
    of all pending readers, which seems appropriate for NULL content.
    
    https://gitlab.gnome.org/GNOME/gtk/issues/2456

 gdk/wayland/gdkselection-wayland.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)
---
diff --git a/gdk/wayland/gdkselection-wayland.c b/gdk/wayland/gdkselection-wayland.c
index b675437951..0dd3aa9ebf 100644
--- a/gdk/wayland/gdkselection-wayland.c
+++ b/gdk/wayland/gdkselection-wayland.c
@@ -860,7 +860,14 @@ gdk_wayland_selection_store (GdkWindow    *window,
     }
 
   stored_selection_add_data (stored_selection, mode, data, len);
-  stored_selection_notify_write (stored_selection);
+
+  if (stored_selection->data)
+    stored_selection_notify_write (stored_selection);
+  else
+    {
+      g_ptr_array_remove_fast (selection->stored_selections,
+                               stored_selection);
+    }
 
   /* Handle the next GDK_SELECTION_REQUEST / store, if any */
   selection->current_request_selection = GDK_NONE;