gtkplacessidebar: avoid accessing destroyed popover

The row and rename popovers are always relative_to a row.
We also keep a pointer to them so we can interact with them in
callbacks.

However, if the row is destroyed its associated popovers will be
destroyed as well as relative_to destroyes and frees memory of its
associated widget when its relative_to widget is destroyed.
If we, for example, update the places while the popover is shown we are
going to access and invalid widget on the next time.

To avoid that, connect to the destroy signal of the popovers and clean
the sidebar pointers when that happens.

https://bugzilla.gnome.org/show_bug.cgi?id=755444

diff --git a/gtk/gtkplacessidebar.c b/gtk/gtkplacessidebar.c
index b2e86e36743aeaf5eb8725358637d034e959d39b..1ed8abe6940e77a5dbd9f04d021718bd8ed43baa 100644 (file)
--- a/gtk/gtkplacessidebar.c
+++ b/gtk/gtkplacessidebar.c
@@ -2412,7 +2412,21 @@ do_rename (GtkButton        *button,
 
   g_clear_pointer (&sidebar->rename_uri, g_free);
 
-  gtk_widget_hide (sidebar->rename_popover);
+  if (sidebar->rename_popover)
+    gtk_widget_hide (sidebar->rename_popover);
+}
+
+static void
+on_rename_popover_destroy (GtkWidget        *rename_popover,
+                           GtkPlacesSidebar *sidebar)
+{
+  if (sidebar)
+    {
+      sidebar->rename_popover = NULL;
+      sidebar->rename_entry = NULL;
+      sidebar->rename_button = NULL;
+      sidebar->rename_error = NULL;
+    }
 }
 
 static void
@@ -2430,6 +2444,9 @@ create_rename_popover (GtkPlacesSidebar *sidebar)
     return;
 
   popover = gtk_popover_new (GTK_WIDGET (sidebar));
+  /* Clean sidebar pointer when its destroyed, most of the times due to its
+   * relative_to associated row being destroyed */
+  g_signal_connect (popover, "destroy", G_CALLBACK (on_rename_popover_destroy), sidebar);
   gtk_popover_set_position (GTK_POPOVER (popover), GTK_POS_RIGHT);
   grid = gtk_grid_new ();
   gtk_container_add (GTK_CONTAINER (popover), grid);
@@ -3383,6 +3400,14 @@ add_open_button (GtkWidget          *box,
   return item;
 }
 
+static void
+on_row_popover_destroy (GtkWidget        *row_popover,
+                        GtkPlacesSidebar *sidebar)
+{
+  if (sidebar)
+    sidebar->popover = NULL;
+}
+
 /* Constructs the popover for the sidebar row if needed */
 static void
 create_row_popover (GtkPlacesSidebar *sidebar,
@@ -3392,6 +3417,9 @@ create_row_popover (GtkPlacesSidebar *sidebar,
   GtkWidget *box;
 
   sidebar->popover = gtk_popover_new (GTK_WIDGET (sidebar));
+  /* Clean sidebar pointer when its destroyed, most of the times due to its
+   * relative_to associated row being destroyed */
+  g_signal_connect (sidebar->popover, "destroy", G_CALLBACK (on_row_popover_destroy), sidebar);
   setup_popover_shadowing (sidebar->popover);
   box = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0);
   g_object_set (box, "margin", 10, NULL);