Precompute groups to guarantee that meta_group_list_windows always returns

2003-06-04  Rob Adams  <robadams@ucla.edu>

	Precompute groups to guarantee that meta_group_list_windows always
	returns the correct list of windows.  See Bug #96973

	* src/window.h: change cached_group variable to group

	* src/window.c (meta_window_new): change cached_group to group and
	call meta_window_compute_group

	* src/groups.c (meta_window_get_group): simply return
	window->group rather than computing it and returning
	window->cached_group
	(meta_window_compute_group): new function computes window->group.
	Designed to be called once from meta_window_new
	(remove_window_from_group): change cached_group to group
	(meta_window_group_leader_changed): call meta_window_compute_group
	instead of meta_window_get_group

4 files changed, 56 insertions, 45 deletions

diff --git a/src/group.c b/src/group.c
index ab35cd26..a1e61c2a 100644
--- a/src/group.c
+++ b/src/group.c
@@ -105,67 +105,72 @@ meta_window_get_group (MetaWindow *window)
 {
   if (window->unmanaging)
     return NULL;
+
+  if (window->group == NULL)
+    meta_window_compute_group (window);
   
-  if (window->cached_group == NULL)
-    {
-      MetaGroup *group;
+  return window->group;
+}
+
+void
+meta_window_compute_group (MetaWindow* window)
+{
+  MetaGroup *group;
 
-      /* use window->xwindow if no window->xgroup_leader */
+  /* use window->xwindow if no window->xgroup_leader */
       
-      group = NULL;
+  group = NULL;
       
-      if (window->display->groups_by_leader)
-        {
-          if (window->xgroup_leader != None)
-            group = g_hash_table_lookup (window->display->groups_by_leader,
-                                         &window->xgroup_leader);
-          else
-            group = g_hash_table_lookup (window->display->groups_by_leader,
-                                         &window->xwindow);
-        }
+  if (window->display->groups_by_leader)
+    {
+      if (window->xgroup_leader != None)
+        group = g_hash_table_lookup (window->display->groups_by_leader,
+                                     &window->xgroup_leader);
+      else
+        group = g_hash_table_lookup (window->display->groups_by_leader,
+                                     &window->xwindow);
+    }
       
-      if (group != NULL)
-        {
-          window->cached_group = group;
-          group->refcount += 1;
-        }
+  if (group != NULL)
+    {
+      window->group = group;
+      group->refcount += 1;
+    }
+  else
+    {
+      if (window->xgroup_leader != None)
+        group = meta_group_new (window->display,
+                                window->xgroup_leader);
       else
-        {
-          if (window->xgroup_leader != None)
-            group = meta_group_new (window->display,
-                                    window->xgroup_leader);
-          else
-            group = meta_group_new (window->display,
-                                    window->xwindow);
+        group = meta_group_new (window->display,
+                                window->xwindow);
           
-          window->cached_group = group;
-        }
+      window->group = group;
+    }
 
-      window->cached_group->windows = g_slist_prepend (window->cached_group->windows,
-                                                       window);
+  window->group->windows = g_slist_prepend (window->group->windows,
+                                                   window);
 
-      meta_topic (META_DEBUG_GROUPS,
-                  "Adding %s to group with leader 0x%lx\n",
-                  window->desc, group->group_leader);
-    }
+  meta_topic (META_DEBUG_GROUPS,
+              "Adding %s to group with leader 0x%lx\n",
+              window->desc, group->group_leader);
 
-  return window->cached_group;
 }
 
 static void
 remove_window_from_group (MetaWindow *window)
 {
-  if (window->cached_group != NULL)
+  if (window->group != NULL)
     {
       meta_topic (META_DEBUG_GROUPS,
                   "Removing %s from group with leader 0x%lx\n",
-                  window->desc, window->cached_group->group_leader);
+                  window->desc, window->group->group_leader);
       
-      window->cached_group->windows =
-        g_slist_remove (window->cached_group->windows,
+      window->group->windows =
+        g_slist_remove (window->group->windows,
                         window);
-      meta_group_unref (window->cached_group);
-      window->cached_group = NULL;
+      meta_group_unref (window->group);
+      window->group = NULL;
     }
 }
 
@@ -173,7 +178,7 @@ void
 meta_window_group_leader_changed (MetaWindow *window)
 {
   remove_window_from_group (window);
-  meta_window_get_group (window);
+  meta_window_compute_group (window);
 }
 
 void
@@ -255,4 +260,5 @@ meta_group_property_notify (MetaGroup  *group,
                               event->xproperty.atom);
 
   return TRUE;
+
 }
diff --git a/src/group.h b/src/group.h
index 6639839a..3f1425b5 100644
--- a/src/group.h
+++ b/src/group.h
@@ -26,6 +26,7 @@
 
 /* note, can return NULL */
 MetaGroup* meta_window_get_group       (MetaWindow *window);
+void       meta_window_compute_group   (MetaWindow* window);
 void       meta_window_shutdown_group  (MetaWindow *window);
 
 void       meta_window_group_leader_changed (MetaWindow *window);
diff --git a/src/window.c b/src/window.c
index 7b65e95e..76e66ea3 100644
--- a/src/window.c
+++ b/src/window.c
@@ -347,6 +347,10 @@ meta_window_new (MetaDisplay *display,
   window->display = display;
   window->workspaces = NULL;
 
+  /* assign the window to its group, or create a new group if needed
+   */
+  meta_window_compute_group (window);
+  
 #ifdef HAVE_XSYNC
   window->update_counter = None;
 #endif
@@ -490,7 +494,7 @@ meta_window_new (MetaDisplay *display,
   window->top_strut = 0;
   window->bottom_strut = 0;
 
-  window->cached_group = NULL;
+  window->group = NULL;
 
   window->using_net_wm_name = FALSE;
   window->using_net_wm_icon_name = FALSE;
@@ -536,7 +540,7 @@ meta_window_new (MetaDisplay *display,
   update_role (window);
   update_net_wm_type (window);
   meta_window_update_icon_now (window);
-  
+
   if (window->initially_iconic)
     {
       /* WM_HINTS said minimized */
diff --git a/src/window.h b/src/window.h
index 2c331d84..2b6a8fa0 100644
--- a/src/window.h
+++ b/src/window.h
@@ -284,7 +284,7 @@ struct _MetaWindow
   int dialog_pipe;
 
   /* maintained by group.c */
-  MetaGroup *cached_group;
+  MetaGroup *group;
 };
 
 #define META_WINDOW_ALLOWS_MOVE(w)     ((w)->has_move_func && !(w)->maximized && !(w)->fullscreen)