Re: [Qemu-devel] [PATCH 12/13] QMP: Introduce qmp_check_input_obj()

[Luiz Capitulino <lcapitulino@redhat.com>]

On Wed, 23 Jun 2010 17:23:54 +0200
Markus Armbruster <armbru@redhat.com> wrote:

> Luiz Capitulino <lcapitulino@redhat.com> writes:
> 
> > This is similar to qmp_check_client_args(), but it checks if
> > the input object follows the specification (QMP/qmp-spec.txt
> > section 2.3).
> >
> > As we're limited to three keys, the work here is quite simple:
> > we iterate over the input object, checking each time if the
> > current argument complies to the specification.
> >
> > Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
> > ---
> >  monitor.c |   45 +++++++++++++++++++++++++++++++++++++++++++++
> >  1 files changed, 45 insertions(+), 0 deletions(-)
> >
> > diff --git a/monitor.c b/monitor.c
> > index 2a29095..a24a152 100644
> > --- a/monitor.c
> > +++ b/monitor.c
> > @@ -4163,6 +4163,46 @@ out:
> >      return err;
> >  }
> >  
> > +/*
> > + * Input object checking rules
> > + *
> > + * 1. "execute" key must exist (not checked here)
> 
> Is it checked elsewhere?  If yes, make it (checked elsewhere already)

Yes, will do.

> > + * 2. "execute" key must be a string
> > + * 3. "arguments" key must be a dict
> > + * 4. "id" key can be anything (ie. json-value)
> > + * 5. Any argument not listed above is considered unexpected
> > + */
> > +static int qmp_check_input_obj(const QDict *input_obj)
> > +{
> > +    const QDictEntry *ent;
> > +
> > +    for (ent = qdict_first(input_obj); ent; ent = qdict_next(input_obj, ent)) {
> > +        const char *arg_name = qdict_entry_key(ent);
> > +        const QObject *arg_obj = qdict_entry_value(ent);
> > +
> > +        if (!strcmp(arg_name, "execute")) {
> > +            if (qobject_type(arg_obj) != QTYPE_QSTRING) {
> > +                qerror_report(QERR_QMP_BAD_INPUT_OBJECT_MEMBER, "execute",
> > +                              "string");
> > +                return -1;
> > +            }
> > +        } else if (!strcmp(arg_name, "arguments")) {
> > +            if (qobject_type(arg_obj) != QTYPE_QDICT) {
> > +                qerror_report(QERR_QMP_BAD_INPUT_OBJECT_MEMBER, "arguments",
> > +                              "object");
> > +                return -1;
> > +            }
> > +        } else if (!strcmp(arg_name, "id")) {
> > +            /* FIXME: check duplicated IDs for async commands */
> > +        } else {
> > +            qerror_report(QERR_QMP_UNEXPECTED_INPUT_OBJECT_MEMBER, arg_name);
> 
> Identifier's a bit on the long side, isn't it?

Yes, suggestions?

> 
> > +            return -1;
> > +        }
> > +    }
> > +
> > +    return 0;
> > +}
> > +
> >  static void handle_qmp_command(JSONMessageParser *parser, QList *tokens)
> >  {
> >      int err;
> > @@ -4187,6 +4227,11 @@ static void handle_qmp_command(JSONMessageParser *parser, QList *tokens)
> >  
> >      input = qobject_to_qdict(obj);
> >  
> > +    err = qmp_check_input_obj(input);
> > +    if (err < 0) {
> > +        goto err_input;
> > +    }
> > +
> >      mon->mc->id = qdict_get(input, "id");
> >      qobject_incref(mon->mc->id);
>