GtkApplication: avoid using stale timestamps

Avoid using a stale timestamp (from the last user interaction with the
application) when a message arrives from D-Bus requesting that a new
window be created.

In this case the most-correct thing that we can do is to use no
timestamp at all.

We modify gdk_x11_display_set_startup_notification_id() to allow a NULL
value to mean "reset everything" and then call this function
unconditionally on receipt of D-Bus activation requests.  The result
will be that a missing desktop-startup-id in the platform-data struct
will reset the timestamp.

Under their default configuration metacity and mutter will both map
windows presented with no timestamp in the foreground.  This could
result in false-positive, but there is very little we can do about that
without the original timestamp from the user event.

https://bugzilla.gnome.org/show_bug.cgi?id=752000

diff --git a/gdk/x11/gdkdisplay-x11.c b/gdk/x11/gdkdisplay-x11.c
index dd608fa8de27ad8bde1b2e5751730cac275577a7..da4382fad72d4a923325bcffe43a7a1dc031ee82 100644 (file)
--- a/gdk/x11/gdkdisplay-x11.c
+++ b/gdk/x11/gdkdisplay-x11.c
@@ -2388,33 +2388,44 @@ gdk_x11_display_set_startup_notification_id (GdkDisplay  *display,
   g_free (display_x11->startup_notification_id);
   display_x11->startup_notification_id = g_strdup (startup_id);
 
-  /* Find the launch time from the startup_id, if it's there.  Newer spec
-   * states that the startup_id is of the form <unique>_TIME<timestamp>
-   */
-  time_str = g_strrstr (startup_id, "_TIME");
-  if (time_str != NULL)
+  if (startup_id != NULL)
     {
-      gulong retval;
-      gchar *end;
-      errno = 0;
+      /* Find the launch time from the startup_id, if it's there.  Newer spec
+       * states that the startup_id is of the form <unique>_TIME<timestamp>
+       */
+      time_str = g_strrstr (startup_id, "_TIME");
+      if (time_str != NULL)
+        {
+          gulong retval;
+          gchar *end;
+          errno = 0;
 
-      /* Skip past the "_TIME" part */
-      time_str += 5;
+          /* Skip past the "_TIME" part */
+          time_str += 5;
 
-      retval = strtoul (time_str, &end, 0);
-      if (end != time_str && errno == 0)
-        display_x11->user_time = retval;
-    }
+          retval = strtoul (time_str, &end, 0);
+          if (end != time_str && errno == 0)
+            display_x11->user_time = retval;
+        }
+      else
+        display_x11->user_time = 0;
 
-  /* Set the startup id on the leader window so it
-   * applies to all windows we create on this display
-   */
-  XChangeProperty (display_x11->xdisplay,
-                   display_x11->leader_window,
-                   gdk_x11_get_xatom_by_name_for_display (display, "_NET_STARTUP_ID"),
-                   gdk_x11_get_xatom_by_name_for_display (display, "UTF8_STRING"), 8,
-                   PropModeReplace,
-                   (guchar *)startup_id, strlen (startup_id));
+      /* Set the startup id on the leader window so it
+       * applies to all windows we create on this display
+       */
+      XChangeProperty (display_x11->xdisplay,
+                       display_x11->leader_window,
+                       gdk_x11_get_xatom_by_name_for_display (display, "_NET_STARTUP_ID"),
+                       gdk_x11_get_xatom_by_name_for_display (display, "UTF8_STRING"), 8,
+                       PropModeReplace,
+                       (guchar *)startup_id, strlen (startup_id));
+    }
+  else
+    {
+      XDeleteProperty (display_x11->xdisplay, display_x11->leader_window,
+                       gdk_x11_get_xatom_by_name_for_display (display, "_NET_STARTUP_ID"));
+      display_x11->user_time = 0;
+    }
 }
 
 static gboolean

diff --git a/gtk/gtkapplication-x11.c b/gtk/gtkapplication-x11.c
index 4ee5b8fec0e73f8e72996931f7da2cdbf54b0cd9..8c52be849033ecd086e041993e65d137f81db3f7 100644 (file)
--- a/gtk/gtkapplication-x11.c
+++ b/gtk/gtkapplication-x11.c
@@ -82,14 +82,11 @@ static void
 gtk_application_impl_x11_before_emit (GtkApplicationImpl *impl,
                                       GVariant           *platform_data)
 {
-  const char *startup_notification_id;
-
-  if (g_variant_lookup (platform_data, "desktop-startup-id",
-                        "&s", &startup_notification_id))
-    {
-      gdk_x11_display_set_startup_notification_id (gdk_display_get_default (),
-                                                   startup_notification_id);
-    }
+  const char *startup_notification_id = NULL;
+
+  g_variant_lookup (platform_data, "desktop-startup-id", "&s", &startup_notification_id);
+
+  gdk_x11_display_set_startup_notification_id (gdk_display_get_default (), startup_notification_id);
 }
 
 static void