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/* Dia -- an diagram creation/manipulation program
* Copyright (C) 1999 Alexander Larsson
*
* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <config.h>
#include "object.h"
/******** ObjectChange for object that just need to get/set state: *****/
typedef struct _ObjectStateChange ObjectStateChange;
struct _ObjectStateChange {
ObjectChange obj_change;
GetStateFunc get_state;
SetStateFunc set_state;
ObjectState *saved_state;
DiaObject *obj;
};
static void
object_state_change_apply_revert(ObjectStateChange *change, DiaObject *obj)
{
ObjectState *old_state;
old_state = change->get_state(change->obj);
change->set_state(change->obj, change->saved_state);
change->saved_state = old_state;
}
static void
object_state_change_free(ObjectStateChange *change)
{
if (change->saved_state->free)
(*change->saved_state->free)(change->saved_state);
g_free(change->saved_state);
}
ObjectChange *new_object_state_change(DiaObject *obj,
ObjectState *old_state,
GetStateFunc get_state,
SetStateFunc set_state )
{
ObjectStateChange *change;
change = g_new(ObjectStateChange, 1);
change->obj_change.apply =
(ObjectChangeApplyFunc) object_state_change_apply_revert;
change->obj_change.revert =
(ObjectChangeRevertFunc) object_state_change_apply_revert;
change->obj_change.free =
(ObjectChangeFreeFunc) object_state_change_free;
change->get_state = get_state;
change->set_state = set_state;
change->obj = obj;
change->saved_state = old_state;
return (ObjectChange *)change;
}
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