Fix gdk_device_get_history() for the core pointer

When filtering out the events for "window" from the events we got for
our "impl_window", don't forget to adjust the returned number of
events because it might be smaller than what XGetMotionEvents has
returned, and free coords we allocated too much. Also if we filtered
away *all* events, return FALSE and get rid of the allocated history
entirely. Together fixes all sorts of mishehavior when painting in
GIMP, from coords going wild to plain crashes and infinite loops.

diff --git a/gdk/x11/gdkinput.c b/gdk/x11/gdkinput.c
index c33f09c9e40e7472bd5f91892b91c3b1fa8fa2ef..6c3cdbb0ea55c4a8041be9c00bacebc16eaf20d6 100644 (file)
--- a/gdk/x11/gdkinput.c
+++ b/gdk/x11/gdkinput.c
@@ -266,7 +266,6 @@ gdk_device_get_history  (GdkDevice         *device,
   GdkWindow *impl_window;
   gboolean result = FALSE;
   int tmp_n_events = 0;
-  int i, j;
 
   g_return_val_if_fail (GDK_WINDOW_IS_X11 (window), FALSE);
 
@@ -284,9 +283,12 @@ gdk_device_get_history  (GdkDevice         *device,
       if (xcoords)
        {
          GdkWindowObject *priv = (GdkWindowObject *)window;
+          int i, j;
+
          coords = _gdk_device_allocate_history (device, tmp_n_events);
          j = 0;
-         for (i=0; i<tmp_n_events; i++)
+
+         for (i = 0; i < tmp_n_events; i++)
            {
              if (impl_coord_in_window (window, xcoords[i].x, xcoords[i].y))
                {
@@ -299,16 +301,32 @@ gdk_device_get_history  (GdkDevice         *device,
 
          XFree (xcoords);
 
-         result = TRUE;
+          /* free the events we allocated too much */
+          for (i = j; i < tmp_n_events; i++)
+            {
+              g_free (coords[i]);
+              coords[i] = NULL;
+            }
+
+          tmp_n_events = j;
+
+          if (tmp_n_events > 0)
+            {
+              result = TRUE;
+            }
+          else
+            {
+              gdk_device_free_history (coords, tmp_n_events);
+              coords = NULL;
+            }
        }
-      else
-       result = FALSE;
     }
   else
     result = _gdk_device_get_history (device, window, start, stop, &coords, &tmp_n_events);
 
   if (n_events)
     *n_events = tmp_n_events;
+
   if (events)
     *events = coords;
   else if (coords)