[gtk+] wayland: Clean up code determining how to map a window

[Jonas Ådahl <jadahl src gnome org>]

commit 9fe40f9a469f2f73f5166472ebc85b7be5ff9947
Author: Jonas Ådahl <jadahl gmail com>
Date:   Tue Oct 13 20:39:02 2015 +0800

    wayland: Clean up code determining how to map a window
    
    Restructure the mapping procedure so that its known up front what the
    expected way mapping is to be done (subsurface, popup or stand alone),
    and warn if it fails to actually map in such a way (for example a popup
    without a parent or device grab, a tooltip without a parent).
    
    https://bugzilla.gnome.org/show_bug.cgi?id=756496

 gdk/wayland/gdkwindow-wayland.c |  100 +++++++++++++++++++++++++++++----------
 1 files changed, 75 insertions(+), 25 deletions(-)
---
diff --git a/gdk/wayland/gdkwindow-wayland.c b/gdk/wayland/gdkwindow-wayland.c
index ab7f384..2447c5d 100644
--- a/gdk/wayland/gdkwindow-wayland.c
+++ b/gdk/wayland/gdkwindow-wayland.c
@@ -888,9 +888,6 @@ gdk_wayland_window_create_subsurface (GdkWindow *window)
   GdkWindowImplWayland *impl, *parent_impl = NULL;
   GdkWaylandDisplay *display_wayland;
 
-  if (GDK_WINDOW_TYPE (window) != GDK_WINDOW_SUBSURFACE)
-    return;
-
   impl = GDK_WINDOW_IMPL_WAYLAND (window->impl);
 
   if (!impl->surface)
@@ -1209,13 +1206,41 @@ find_grab_input_seat (GdkWindow *window, GdkWindow *transient_for)
 static gboolean
 should_be_mapped (GdkWindow *window)
 {
+  GdkWindowImplWayland *impl = GDK_WINDOW_IMPL_WAYLAND (window->impl);
+
   /* Don't map crazy temp that GTK+ uses for internal X11 shenanigans. */
   if (window->window_type == GDK_WINDOW_TEMP && window->x < 0 && window->y < 0)
     return FALSE;
 
+  if (impl->hint == GDK_WINDOW_TYPE_HINT_DND)
+    return FALSE;
+
   return TRUE;
 }
 
+static gboolean
+should_map_as_subsurface (GdkWindow *window)
+{
+  if (GDK_WINDOW_TYPE (window) == GDK_WINDOW_SUBSURFACE)
+    return TRUE;
+
+  return FALSE;
+}
+
+static gboolean
+should_map_as_popup (GdkWindow *window)
+{
+  GdkWindowImplWayland *impl = GDK_WINDOW_IMPL_WAYLAND (window->impl);
+
+  if (impl->hint == GDK_WINDOW_TYPE_HINT_POPUP_MENU ||
+      impl->hint == GDK_WINDOW_TYPE_HINT_DROPDOWN_MENU ||
+      impl->hint == GDK_WINDOW_TYPE_HINT_UTILITY ||
+      impl->hint == GDK_WINDOW_TYPE_HINT_COMBO)
+    return TRUE;
+
+  return FALSE;
+}
+
 static void
 gdk_wayland_window_map (GdkWindow *window)
 {
@@ -1225,8 +1250,22 @@ gdk_wayland_window_map (GdkWindow *window)
   if (!should_be_mapped (window))
     return;
 
-  if (!impl->mapped && !impl->use_custom_surface)
+  if (impl->mapped || impl->use_custom_surface)
+    return;
+
+  if (should_map_as_subsurface (window))
     {
+      if (impl->transient_for)
+        gdk_wayland_window_create_subsurface (window);
+      else
+        g_warning ("Couldn't map as window %p as susburface yet because it doesn't have a parent",
+                   window);
+    }
+  else if (should_map_as_popup (window))
+    {
+      gboolean create_fallback = FALSE;
+      struct wl_seat *grab_input_seat;
+
       /* Popup menus can appear without a transient parent, which means they
        * cannot be positioned properly on Wayland. This attempts to guess the
        * surface they should be positioned with by finding the surface beneath
@@ -1278,29 +1317,43 @@ gdk_wayland_window_map (GdkWindow *window)
       else
         transient_for = impl->transient_for;
 
-      if (transient_for &&
-          GDK_WINDOW_TYPE (window) != GDK_WINDOW_SUBSURFACE)
+      if (!transient_for)
+        {
+          g_warning ("Couldn't map as window %p as popup because it doesn't have a parent",
+                     window);
+
+          create_fallback = TRUE;
+        }
+      else
         {
-          struct wl_seat *grab_input_seat = find_grab_input_seat (window, transient_for);
-          if (grab_input_seat &&
-              (impl->hint == GDK_WINDOW_TYPE_HINT_POPUP_MENU ||
-               impl->hint == GDK_WINDOW_TYPE_HINT_DROPDOWN_MENU ||
-               impl->hint == GDK_WINDOW_TYPE_HINT_COMBO))
+          grab_input_seat = find_grab_input_seat (window, transient_for);
+
+          if (!grab_input_seat)
             {
-              gdk_wayland_window_create_xdg_popup (window,
-                                                  transient_for,
-                                                  grab_input_seat);
-              goto mapped;
+              g_warning ("Couldn't map window %p as popup because no grabbed seat found",
+                         window);
+
+              create_fallback = TRUE;
             }
         }
 
-      if (impl->hint != GDK_WINDOW_TYPE_HINT_DND &&
-          GDK_WINDOW_TYPE (window) != GDK_WINDOW_SUBSURFACE)
-        gdk_wayland_window_create_xdg_surface (window);
-
-    mapped:
-      impl->mapped = TRUE;
+      if (!create_fallback)
+        {
+          gdk_wayland_window_create_xdg_popup (window,
+                                               transient_for,
+                                               grab_input_seat);
+        }
+      else
+        {
+          gdk_wayland_window_create_xdg_surface (window);
+        }
     }
+  else
+    {
+      gdk_wayland_window_create_xdg_surface (window);
+    }
+
+  impl->mapped = TRUE;
 }
 
 static void
@@ -1312,9 +1365,6 @@ gdk_wayland_window_show (GdkWindow *window,
   if (!impl->surface)
     gdk_wayland_window_create_surface (window);
 
-  if (GDK_WINDOW_TYPE (window) == GDK_WINDOW_SUBSURFACE)
-    gdk_wayland_window_create_subsurface (window);
-
   gdk_wayland_window_map (window);
 
   _gdk_make_event (window, GDK_MAP, NULL, FALSE);
@@ -1846,7 +1896,7 @@ gdk_wayland_window_set_transient_for (GdkWindow *window,
 
   gdk_wayland_window_sync_parent (window);
 
-  if (GDK_WINDOW_TYPE (window) == GDK_WINDOW_SUBSURFACE &&
+  if (should_map_as_subsurface (window) &&
       parent && gdk_window_is_visible (window))
     gdk_wayland_window_create_subsurface (window);
 }