Index: data_parent.h
===================================================================
--- data_parent.h	(nonexistent)
+++ data_parent.h	(revision 9013)
@@ -0,0 +1,65 @@
+/*
+ *                            COPYRIGHT
+ *
+ *  pcb-rnd, interactive printed circuit board design
+ *  Copyright (C) 2016..2017 Tibor 'Igor2' Palinkas
+ * 
+ *  This module, rats.c, was written and is Copyright (C) 1997 by harry eaton
+ *  this module is also subject to the GNU GPL as described below
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#ifndef PCB_DATA_PARENT_H
+#define PCB_DATA_PARENT_H
+
+#include "global_typedefs.h"
+
+/* which elem of the parent union is active */
+typedef enum pcb_parenttype_e {
+	PCB_PARENT_INVALID = 0,  /* invalid or unknown */
+	PCB_PARENT_LAYER,        /* object is on a layer */
+	PCB_PARENT_ELEMENT,      /* object is part of an element */
+	PCB_PARENT_DATA          /* global objects like via */
+} pcb_parenttype_t;
+
+/* class is e.g. PCB_OBJ_CLASS_OBJ */
+#define PCB_OBJ_IS_CLASS(type, class)  (((type) & PCB_OBJ_CLASS_MASK) == (class))
+
+union pcb_parent_s {
+	void           *any;
+	pcb_layer_t    *layer;
+	pcb_data_t     *data;
+	pcb_element_t  *element;
+};
+
+#define PCB_PARENT_TYPENAME_layer    PCB_PARENT_LAYER
+#define PCB_PARENT_TYPENAME_data     PCB_PARENT_DATA
+#define PCB_PARENT_TYPENAME_element  PCB_PARENT_ELEMENT
+
+#define PCB_SET_PARENT(obj, ptype, parent_ptr) \
+	do { \
+		obj->parent_type = PCB_PARENT_TYPENAME_ ## ptype; \
+		obj->parent.ptype = parent_ptr; \
+	} while(0)
+
+#define PCB_CLEAR_PARENT(obj) \
+	do { \
+		obj->parent_type = PCB_PARENT_INVALID; \
+		obj->parent.any = NULL; \
+	} while(0)
+
+#endif