[gtk+] GtkSearchEngine: Avoid a crash

[Matthias Clasen <matthiasc src gnome org>]

commit ed50772b4154fb7fa3d48be3c37785199ed21276
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Jun 19 00:32:49 2015 -0400

    GtkSearchEngine: Avoid a crash
    
    Add a destroy notify for the data of the callback, so we don't
    end up leaving a dangling pointer behind for a short while if
    the native engine is finalized before the simple one. This
    was showing up as crash when typing and backspacing in the
    search entry of the file chooser.

 gtk/gtksearchengine.c       |    3 ++-
 gtk/gtksearchenginesimple.c |   15 ++++++++++++++-
 gtk/gtksearchenginesimple.h |    3 ++-
 3 files changed, 18 insertions(+), 3 deletions(-)
---
diff --git a/gtk/gtksearchengine.c b/gtk/gtksearchengine.c
index de992e5..67110f9 100644
--- a/gtk/gtksearchengine.c
+++ b/gtk/gtksearchengine.c
@@ -334,7 +334,8 @@ _gtk_search_engine_new (void)
       connect_engine_signals (engine->priv->native, engine);
       _gtk_search_engine_simple_set_indexed_cb (GTK_SEARCH_ENGINE_SIMPLE (engine->priv->simple),
                                                 _gtk_search_engine_tracker_is_indexed,
-                                                engine->priv->native);
+                                                g_object_ref (engine->priv->native),
+                                                g_object_unref);
     }
 #endif
 
diff --git a/gtk/gtksearchenginesimple.c b/gtk/gtksearchenginesimple.c
index b405aef..00543ea 100644
--- a/gtk/gtksearchenginesimple.c
+++ b/gtk/gtksearchenginesimple.c
@@ -57,6 +57,7 @@ struct _GtkSearchEngineSimplePrivate
 
   GtkSearchEngineSimpleIsIndexed is_indexed_callback;
   gpointer                       is_indexed_data;
+  GDestroyNotify                 is_indexed_data_destroy;
 };
 
 
@@ -83,6 +84,13 @@ gtk_search_engine_simple_dispose (GObject *object)
       priv->active_search = NULL;
     }
 
+  if (priv->is_indexed_data_destroy)
+    priv->is_indexed_data_destroy (priv->is_indexed_data);
+
+  priv->is_indexed_callback = NULL;
+  priv->is_indexed_data = NULL;
+  priv->is_indexed_data_destroy = NULL;
+
   G_OBJECT_CLASS (_gtk_search_engine_simple_parent_class)->dispose (object);
 }
 
@@ -365,8 +373,13 @@ _gtk_search_engine_simple_new (void)
 void
 _gtk_search_engine_simple_set_indexed_cb (GtkSearchEngineSimple          *engine,
                                           GtkSearchEngineSimpleIsIndexed  callback,
-                                          gpointer                        data)
+                                          gpointer                        data,
+                                          GDestroyNotify                  destroy)
 {
+  if (engine->priv->is_indexed_data_destroy)
+    engine->priv->is_indexed_data_destroy (engine->priv->is_indexed_data);
+
   engine->priv->is_indexed_callback = callback;
   engine->priv->is_indexed_data = data;
+  engine->priv->is_indexed_data_destroy = destroy;
 }
diff --git a/gtk/gtksearchenginesimple.h b/gtk/gtksearchenginesimple.h
index 83a60b1..421b208 100644
--- a/gtk/gtksearchenginesimple.h
+++ b/gtk/gtksearchenginesimple.h
@@ -57,7 +57,8 @@ typedef gboolean (*GtkSearchEngineSimpleIsIndexed) (GFile *location, gpointer da
 
 void             _gtk_search_engine_simple_set_indexed_cb (GtkSearchEngineSimple *engine,
                                                            GtkSearchEngineSimpleIsIndexed callback,
-                                                           gpointer                       data);
+                                                           gpointer                       data,
+                                                           GDestroyNotify                 destroy);
 
 G_END_DECLS