diff options
| -rw-r--r-- | include/qapi/qmp/qobject.h | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/include/qapi/qmp/qobject.h b/include/qapi/qmp/qobject.h index 012439a..e022707 100644 --- a/include/qapi/qmp/qobject.h +++ b/include/qapi/qmp/qobject.h @@ -50,6 +50,21 @@ struct QObject { #define QDECREF(obj) \ qobject_decref(obj ? QOBJECT(obj) : NULL) +/* Required for qobject_to() */ +#define QTYPE_CAST_TO_QNull QTYPE_QNULL +#define QTYPE_CAST_TO_QNum QTYPE_QNUM +#define QTYPE_CAST_TO_QString QTYPE_QSTRING +#define QTYPE_CAST_TO_QDict QTYPE_QDICT +#define QTYPE_CAST_TO_QList QTYPE_QLIST +#define QTYPE_CAST_TO_QBool QTYPE_QBOOL + +QEMU_BUILD_BUG_MSG(QTYPE__MAX != 7, + "The QTYPE_CAST_TO_* list needs to be extended"); + +#define qobject_to(type, obj) ({ \ + QObject *_tmp = qobject_check_type(obj, glue(QTYPE_CAST_TO_, type)); \ + _tmp ? container_of(_tmp, type, base) : (type *)NULL; }) + /* Initialize an object to default values */ static inline void qobject_init(QObject *obj, QType type) { @@ -102,4 +117,18 @@ static inline QType qobject_type(const QObject *obj) return obj->type; } +/** + * qobject_check_type(): Helper function for the qobject_to() macro. + * Return @obj, but only if @obj is not NULL and @type is equal to + * @obj's type. Return NULL otherwise. + */ +static inline QObject *qobject_check_type(const QObject *obj, QType type) +{ + if (obj && qobject_type(obj) == type) { + return (QObject *)obj; + } else { + return NULL; + } +} + #endif /* QOBJECT_H */ |