nuke the lists of struts here, to improve confidence that we never try to

2003-06-26  Havoc Pennington  <hp@pobox.com>

	* src/workspace.c (meta_workspace_invalidate_work_area): nuke the
	lists of struts here, to improve confidence that we never try to
	use them after a window with rects in the list gets freed.
	(it wasn't broken before I don't think, just making the
	code more robust against future mods)

	* src/window.c (meta_window_update_struts): replace magic "75"
	with a macro

	* src/constraints.c (constraint_hints_applies_func): don't apply
	hints to maximized or fullscreen, rather than only fullscreen
	(constrain_move): add paranoia max number of iterations to the
	heuristic loop

4 files changed, 61 insertions, 23 deletions

diff --git a/ChangeLog b/ChangeLog
index 005caf01..6dd0edeb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,19 @@
+2003-06-26  Havoc Pennington  <hp@pobox.com>
+
+	* src/workspace.c (meta_workspace_invalidate_work_area): nuke the
+	lists of struts here, to improve confidence that we never try to
+	use them after a window with rects in the list gets freed.
+	(it wasn't broken before I don't think, just making the 
+	code more robust against future mods)
+
+	* src/window.c (meta_window_update_struts): replace magic "75"
+	with a macro
+
+	* src/constraints.c (constraint_hints_applies_func): don't apply
+	hints to maximized or fullscreen, rather than only fullscreen
+	(constrain_move): add paranoia max number of iterations to the 
+	heuristic loop
+
 2003-06-26  Rob Adams  <robadams@ucla.edu>
 
 	Add keybinding to allow the user to toggle _NET_WM_STATE_ABOVE on
diff --git a/src/constraints.c b/src/constraints.c
index abf0b650..74fefcb0 100644
--- a/src/constraints.c
+++ b/src/constraints.c
@@ -364,9 +364,8 @@ get_outermost_onscreen_positions (MetaWindow           *window,
   /* to handle struts, we get the list of workspaces for the window
    * and traverse all the struts in each of the cached strut lists for
    * the workspaces.  Note that because the workarea has already been
-   * computed, these strut lists should already be up to date.  No
-   * memory allocation should take place in this function for
-   * performance.
+   * computed, these strut lists should already be up to date. This function
+   * should have good performance since we call it a lot.
    */
 
   current = *orig;
@@ -681,10 +680,12 @@ static const Constraint constraint_onscreen = {
  *
  */
 
+#define USE_HINTS_FOR_WINDOW_STATE(window) (!((window)->fullscreen || (window)->maximized))
+
 static gboolean
 constraint_hints_applies_func (MetaWindow *window)
 {
-  return (!window->fullscreen);
+  return USE_HINTS_FOR_WINDOW_STATE (window);
 }
 
 static void
@@ -912,8 +913,12 @@ constrain_move (MetaWindow           *window,
 {
   const Constraint **cp;
   int old_x, old_y;
+  int paranoia;
 
-
+  /* Evidence that we can't actually prove this algorithm is right */
+#define MAX_ITERATIONS 10
+  paranoia = 0;
+  
   do {
     old_x = x_delta;
     old_y = y_delta;
@@ -936,10 +941,16 @@ constrain_move (MetaWindow           *window,
         ++cp;
       }
 
-  } while ((old_x != x_delta) || (old_y != y_delta));
+    ++paranoia;
+  } while (((old_x != x_delta) || (old_y != y_delta)) && paranoia < MAX_ITERATIONS);
 
   new->x = orig->x + x_delta;
   new->y = orig->y + y_delta;
+
+  if (paranoia >= MAX_ITERATIONS)
+    meta_topic (META_DEBUG_GEOMETRY,
+                "Constraints were never satisfied for window %s\n",
+                window->desc);
 }
 
 static void
@@ -1154,6 +1165,10 @@ update_position_limits (MetaWindow          *window,
   int nw_x, nw_y;
   int se_x, se_y;
 
+  /* For maximized windows the limits are the work area, for
+   * other windows we see which struts apply based on the
+   * window's position later on
+   */
   if (window->maximized)
     {
       nw_x = MIN (info->work_area_xinerama.x, info->work_area_screen.x);
diff --git a/src/window.c b/src/window.c
index 8ff177ee..8d11b8fa 100644
--- a/src/window.c
+++ b/src/window.c
@@ -4842,6 +4842,8 @@ meta_window_update_struts (MetaWindow *window)
   MetaRectangle new_right;
   MetaRectangle new_top;
   MetaRectangle new_bottom;
+
+#define MIN_EMPTY (75)
   
   meta_verbose ("Updating struts for %s\n", window->desc);
   
@@ -4893,13 +4895,13 @@ meta_window_update_struts (MetaWindow *window)
         {
           new_has_struts = TRUE;
           new_left.width = MIN ((int)struts[0], 
-                                window->screen->width/2 - 75);
+                                window->screen->width/2 - MIN_EMPTY);
           new_right.width = MIN ((int)struts[1], 
-                                 window->screen->width/2 - 75);
+                                 window->screen->width/2 - MIN_EMPTY);
           new_top.height = MIN ((int)struts[2], 
-                                window->screen->height/2 - 75);
+                                window->screen->height/2 - MIN_EMPTY);
           new_bottom.height = MIN ((int)struts[3], 
-                                   window->screen->height/2 - 75);
+                                   window->screen->height/2 - MIN_EMPTY);
           new_right.x = window->screen->width - 
             new_right.width;
           new_bottom.y = window->screen->height - 
@@ -4945,13 +4947,13 @@ meta_window_update_struts (MetaWindow *window)
             {
               new_has_struts = TRUE;
               new_left.width = MIN ((int)struts[0], 
-                                    window->screen->width/2 - 75);
+                                    window->screen->width/2 - MIN_EMPTY);
               new_right.width = MIN ((int)struts[1], 
-                                     window->screen->width/2 - 75);
+                                     window->screen->width/2 - MIN_EMPTY);
               new_top.height = MIN ((int)struts[2], 
-                                    window->screen->height/2 - 75);
+                                    window->screen->height/2 - MIN_EMPTY);
               new_bottom.height = MIN ((int)struts[3], 
-                                       window->screen->height/2 - 75);
+                                       window->screen->height/2 - MIN_EMPTY);
               new_left.x = 0;
               new_right.x = window->screen->width - 
                 new_right.width;
diff --git a/src/workspace.c b/src/workspace.c
index d84539e2..09dc25a5 100644
--- a/src/workspace.c
+++ b/src/workspace.c
@@ -348,6 +348,15 @@ meta_workspace_invalidate_work_area (MetaWorkspace *workspace)
 
   g_free (workspace->work_areas);
   workspace->work_areas = NULL;
+      
+  g_slist_free (workspace->left_struts);
+  workspace->left_struts = NULL;
+  g_slist_free (workspace->right_struts);
+  workspace->right_struts = NULL;
+  g_slist_free (workspace->top_struts);
+  workspace->top_struts = NULL;
+  g_slist_free (workspace->bottom_struts);
+  workspace->bottom_struts = NULL;
   
   workspace->work_areas_invalid = TRUE;
 
@@ -385,16 +394,12 @@ ensure_work_areas_validated (MetaWorkspace *workspace)
 
   if (!workspace->work_areas_invalid)
     return;
-      
-  g_slist_free (workspace->left_struts);
-  workspace->left_struts = NULL;
-  g_slist_free (workspace->right_struts);
-  workspace->right_struts = NULL;
-  g_slist_free (workspace->top_struts);
-  workspace->top_struts = NULL;
-  g_slist_free (workspace->bottom_struts);
-  workspace->bottom_struts = NULL;
 
+  g_assert (workspace->top_struts == NULL);
+  g_assert (workspace->bottom_struts == NULL);
+  g_assert (workspace->left_struts == NULL);
+  g_assert (workspace->right_struts == NULL);
+  
   windows = meta_workspace_list_windows (workspace);
 
   g_free (workspace->work_areas);