/* Chrysalide - Outil d'analyse de fichiers binaires
* objhole.h - prototypes pour l'utilisation d'un espace inutilisé dans la structure GObject
*
* Copyright (C) 2020 Cyrille Bagard
*
* This file is part of Chrysalide.
*
* Chrysalide 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 3 of the License, or
* (at your option) any later version.
*
* Chrysalide 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 Chrysalide. If not, see .
*/
#ifndef _GLIBEXT_OBJHOLE_H
#define _GLIBEXT_OBJHOLE_H
#include
#include "../common/cpp.h"
/**
* Une structure GObject a la définition suivante :
*
* struct _GObject
* {
* GTypeInstance g_type_instance;
* volatile guint ref_count;
* GData *qdata;
* };
*
* L'espace entre les deux derniers champs est exploité ici.
*/
#define INIT_GOBJECT_EXTRA(obj) \
do \
{ \
guint *___space; \
___space = (((guint *)&obj->ref_count) + 1); \
BUILD_BUG_ON((___space + 1) == (guint *)&obj->qdata); \
*___space = 0; \
} \
while (0)
#define GET_GOBJECT_EXTRA(obj, tp) \
({ \
BUILD_BUG_ON(sizeof(tp) > sizeof(guint)); \
tp *___result; \
___result = (tp *)(((guint *)&obj->ref_count) + 1); \
BUILD_BUG_ON((___result + 1) == (tp *)&obj->qdata); \
___result; \
})
/**
* Choix du bit de verrou pour le champ "lock".
*
* Dans la structure exploitant le mot utilisé ici, ce verrou est généralement
* placé dans le bit de poids fort pour les objets qui l'utilisent.
*/
#if __BYTE_ORDER == __LITTLE_ENDIAN
# define HOLE_LOCK_BIT 31
#elif __BYTE_ORDER == __BIG_ENDIAN
# define HOLE_LOCK_BIT 0
#else
# error "Unknown byte order"
#endif
#endif /* _GLIBEXT_OBJHOLE_H */