unicorn/qemu/qobject/qobject.c
Marc-André Lureau 2ca916e106
qobject: Ensure base is at offset 0
All QObject types have the base QObject as their first field. This
allows the simplification of qobject_to().

Backports commit 7ee9edfdb117da47c86c9764d90f0be11a648666 from qemu
2018-05-04 09:54:36 -04:00

72 lines
1.7 KiB
C

/*
* QObject
*
* Copyright (C) 2015 Red Hat, Inc.
*
* This work is licensed under the terms of the GNU LGPL, version 2.1
* or later. See the COPYING.LIB file in the top-level directory.
*/
#include "qemu-common.h"
#include "qapi/qmp/qbool.h"
#include "qapi/qmp/qnull.h"
#include "qapi/qmp/qnum.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qlist.h"
#include "qapi/qmp/qstring.h"
QEMU_BUILD_BUG_MSG(
offsetof(QNull, base) != 0 ||
offsetof(QNum, base) != 0 ||
offsetof(QString, base) != 0 ||
offsetof(QDict, base) != 0 ||
offsetof(QList, base) != 0 ||
offsetof(QBool, base) != 0,
"base qobject must be at offset 0");
static void (*qdestroy[QTYPE__MAX])(QObject *) = {
NULL, /* No such object exists */
NULL, /* qnull_ is indestructible */
qnum_destroy_obj,
qstring_destroy_obj,
qdict_destroy_obj,
qlist_destroy_obj,
qbool_destroy_obj,
};
void qobject_destroy(QObject *obj)
{
assert(!obj->refcnt);
assert(QTYPE_QNULL < obj->type && obj->type < QTYPE__MAX);
qdestroy[obj->type](obj);
}
static bool (*qis_equal[QTYPE__MAX])(const QObject *, const QObject *) = {
NULL, /* No such object exists */
qnull_is_equal,
qnum_is_equal,
qstring_is_equal,
qdict_is_equal,
qlist_is_equal,
qbool_is_equal,
};
bool qobject_is_equal(const QObject *x, const QObject *y)
{
/* We cannot test x == y because an object does not need to be
* equal to itself (e.g. NaN floats are not). */
if (!x && !y) {
return true;
}
if (!x || !y || x->type != y->type) {
return false;
}
assert(QTYPE_NONE < x->type && x->type < QTYPE__MAX);
return qis_equal[x->type](x, y);
}