[gtk/BUG_filechooser_async_data_loss_GTK4] GtkFilechooserWidget: prevent oblivious selection of file

[Nelson Benítez León <nbenitez src gnome org>]

commit 45d7051dffcc51d9b6a08aa35f3838f2bdd3e2dd
Author: Nelson Benítez León <nbenitezl gmail com>
Date:   Tue Apr 14 16:01:12 2020 -0400

    GtkFilechooserWidget: prevent oblivious selection of file
    
    which could happen after confirming the "file overwrite"
    dialog and may result in a different file being overwritten
    causing data loss.
    
    The oblivious file selection can be done by a mouse
    click or keyboard press sent inadvertently just after
    confirming the "file overwrite" dialog (and before the
    enclosing GtkfilechooserDialog is closed).
    
    Fixed by adding a flag to ignore any button/key press
    events sent to the file list. We set this flag just
    after the user accepts the "file overwrite" dialog (which
    means the enclosing GtkfilechooserDialog is about to
    get closed). And we restablish the flag when the dialog
    is shown again (in its map() handler).
    
    Fixes data loss issue #2288

 gtk/gtkfilechooserwidget.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)
---
diff --git a/gtk/gtkfilechooserwidget.c b/gtk/gtkfilechooserwidget.c
index 05e9cbe75e..78917e9704 100644
--- a/gtk/gtkfilechooserwidget.c
+++ b/gtk/gtkfilechooserwidget.c
@@ -361,6 +361,7 @@ struct _GtkFileChooserWidget
   guint create_folders : 1;
   guint auto_selecting_first_row : 1;
   guint starting_search : 1;
+  guint browse_files_interaction_frozen : 1;
 };
 
 struct _GtkFileChooserWidgetClass
@@ -2029,6 +2030,33 @@ files_list_clicked (GtkGesture           *gesture,
   list_popup_menu_cb (NULL, NULL, impl);
 }
 
+static void
+files_list_restrict_clicking (GtkGestureClick      *gesture,
+                              int                   n_press,
+                              double                x,
+                              double                y,
+                              GtkFileChooserWidget *impl)
+{
+  if (impl->browse_files_interaction_frozen)
+    gtk_event_controller_reset (GTK_EVENT_CONTROLLER (gesture));
+}
+
+static gboolean
+files_list_restrict_key_presses (GtkEventControllerKey *controller,
+                                 guint                  keyval,
+                                 guint                  keycode,
+                                 GdkModifierType        state,
+                                 GtkFileChooserWidget  *impl)
+{
+  if (impl->browse_files_interaction_frozen)
+    {
+      gtk_event_controller_reset (GTK_EVENT_CONTROLLER (controller));
+      return GDK_EVENT_STOP;
+    }
+
+  return GDK_EVENT_PROPAGATE;
+}
+
 /* Callback used when a button is pressed on the file list.  We trap button 3 to
  * bring up a popup menu.
  */
@@ -3438,6 +3466,8 @@ gtk_file_chooser_widget_map (GtkWidget *widget)
 
   profile_start ("start", NULL);
 
+  impl->browse_files_interaction_frozen = FALSE;
+
   GTK_WIDGET_CLASS (gtk_file_chooser_widget_parent_class)->map (widget);
 
   settings_load (impl);
@@ -5726,6 +5756,11 @@ confirm_dialog_should_accept_filename (GtkFileChooserWidget *impl,
 
   response = gtk_dialog_run (GTK_DIALOG (dialog));
 
+  if (response == GTK_RESPONSE_ACCEPT)
+    /* Dialog is now going to be closed, so prevent any button/key presses to
+     * file list (will be restablished on next map()). Fixes data loss bug #2288 */
+    impl->browse_files_interaction_frozen = TRUE;
+
   gtk_widget_destroy (dialog);
 
   return (response == GTK_RESPONSE_ACCEPT);
@@ -7749,6 +7784,20 @@ post_process_ui (GtkFileChooserWidget *impl)
   shortcut = gtk_shortcut_new (trigger, action);
   gtk_shortcut_controller_add_shortcut (GTK_SHORTCUT_CONTROLLER (controller), shortcut);
   gtk_widget_add_controller (GTK_WIDGET (impl->browse_files_tree_view), controller);
+
+  /* Add ability to restrict interaction on file list (click and key_press events),
+   * needed to prevent data loss bug #2288 */
+  gesture = gtk_gesture_click_new ();
+  gtk_gesture_single_set_button (GTK_GESTURE_SINGLE (gesture), 0);
+  gtk_gesture_single_set_exclusive (GTK_GESTURE_SINGLE (gesture), TRUE);
+  gtk_event_controller_set_propagation_phase (GTK_EVENT_CONTROLLER (gesture), GTK_PHASE_CAPTURE);
+  g_signal_connect (gesture, "pressed", G_CALLBACK (files_list_restrict_clicking), impl);
+  gtk_widget_add_controller (impl->browse_files_tree_view, GTK_EVENT_CONTROLLER (gesture));
+
+  controller = gtk_event_controller_key_new ();
+  gtk_event_controller_set_propagation_phase (controller, GTK_PHASE_CAPTURE);
+  g_signal_connect (controller, "key-pressed", G_CALLBACK (files_list_restrict_key_presses), impl);
+  gtk_widget_add_controller (impl->browse_files_tree_view, controller);
 }
 
 void