| Message ID | 1324036918-2405-3-git-send-email-pbonzini@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 12/16/2011 06:01 AM, Paolo Bonzini wrote: > A NULL qobj can occur when a parameter is fetched via qdict_get, but > the parameter is not in the command. By returning NULL, the caller can > choose whether to raise a missing parameter error, an invalid parameter > type error, or use a default value. For example, qom-set could can > use this to reset a property to its default value, though at this time > it will fail with "Invalid parameter type". In any case, anything is > better than crashing! Reviewed-by: Anthony Liguori <aliguori@us.ibm.com> Regards, Anthony Liguori > > Signed-off-by: Paolo Bonzini<pbonzini@redhat.com> > --- > qapi/qmp-input-visitor.c | 10 ++++++---- > 1 files changed, 6 insertions(+), 4 deletions(-) > > diff --git a/qapi/qmp-input-visitor.c b/qapi/qmp-input-visitor.c > index 8cbc0ab..c78022b 100644 > --- a/qapi/qmp-input-visitor.c > +++ b/qapi/qmp-input-visitor.c > @@ -49,10 +49,12 @@ static const QObject *qmp_input_get_object(QmpInputVisitor *qiv, > qobj = qiv->stack[qiv->nb_stack - 1].obj; > } > > - if (name&& qobject_type(qobj) == QTYPE_QDICT) { > - return qdict_get(qobject_to_qdict(qobj), name); > - } else if (qiv->nb_stack> 0&& qobject_type(qobj) == QTYPE_QLIST) { > - return qlist_entry_obj(qiv->stack[qiv->nb_stack - 1].entry); > + if (qobj) { > + if (name&& qobject_type(qobj) == QTYPE_QDICT) { > + return qdict_get(qobject_to_qdict(qobj), name); > + } else if (qiv->nb_stack> 0&& qobject_type(qobj) == QTYPE_QLIST) { > + return qlist_entry_obj(qiv->stack[qiv->nb_stack - 1].entry); > + } > } > > return qobj;
diff --git a/qapi/qmp-input-visitor.c b/qapi/qmp-input-visitor.c index 8cbc0ab..c78022b 100644 --- a/qapi/qmp-input-visitor.c +++ b/qapi/qmp-input-visitor.c @@ -49,10 +49,12 @@ static const QObject *qmp_input_get_object(QmpInputVisitor *qiv, qobj = qiv->stack[qiv->nb_stack - 1].obj; } - if (name && qobject_type(qobj) == QTYPE_QDICT) { - return qdict_get(qobject_to_qdict(qobj), name); - } else if (qiv->nb_stack > 0 && qobject_type(qobj) == QTYPE_QLIST) { - return qlist_entry_obj(qiv->stack[qiv->nb_stack - 1].entry); + if (qobj) { + if (name && qobject_type(qobj) == QTYPE_QDICT) { + return qdict_get(qobject_to_qdict(qobj), name); + } else if (qiv->nb_stack > 0 && qobject_type(qobj) == QTYPE_QLIST) { + return qlist_entry_obj(qiv->stack[qiv->nb_stack - 1].entry); + } } return qobj;
A NULL qobj can occur when a parameter is fetched via qdict_get, but the parameter is not in the command. By returning NULL, the caller can choose whether to raise a missing parameter error, an invalid parameter type error, or use a default value. For example, qom-set could can use this to reset a property to its default value, though at this time it will fail with "Invalid parameter type". In any case, anything is better than crashing! Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- qapi/qmp-input-visitor.c | 10 ++++++---- 1 files changed, 6 insertions(+), 4 deletions(-)