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/*
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* Copyright (C) 2004 Dizzy (dizzy@roedu.net)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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/*
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* Reference Change Mechanism
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* an abstract interface to implement safe management of references of objects
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* which do not share any specific dependencies
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*/
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#ifndef __RCM_H_TYPES__
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#define __RCM_H_TYPES__
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#include "common/elist.h"
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/* reference change mechanism main object
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* an object which wishes to be referenced using RCM has to include this */
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typedef struct {
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unsigned count;
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t_elist refs; /* list of registered references */
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} t_rcm;
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/* callback called when the object referenced is moved/deleted */
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typedef int (*t_chref_cb)(void *data, void *newref);
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/* registered reference object
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* an object which wants to register it's references to an rcm enabled object
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* will have to include one of this for every rcm enabled referenced object
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*/
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typedef struct {
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t_chref_cb chref;
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void *data;
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t_elist refs_link;
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} t_rcm_regref;
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#endif /* __RCM_H_TYPES__ */
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#ifndef __RCM_H_PROTOS__
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#define __RCM_H_PROTOS__
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extern void rcm_init(t_rcm *rcm);
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extern void rcm_regref_init(t_rcm_regref *regref, t_chref_cb cb, void *data);
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extern void rcm_get(t_rcm *rcm, t_rcm_regref *regref);
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extern void rcm_put(t_rcm *rcm, t_rcm_regref *regref);
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/* the main function, cycles through the registered references and calls the
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* registered callback with the new reference */
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extern void rcm_chref(t_rcm *rcm, void *newref);
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#endif /* __RCM_H_PROTOS__ */
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