Re: [Qemu-devel] [PATCH 2/7] qapi: QMP input visitor, handle floats parsed as ints

[Michael Roth <mdroth@linux.vnet.ibm.com>]

On Fri, May 11, 2012 at 07:16:18PM +0200, Andreas Färber wrote:
> Am 11.05.2012 19:04, schrieb Michael Roth:
> > On Fri, May 11, 2012 at 01:22:33PM -0300, Luiz Capitulino wrote:
> >> On Fri, 27 Apr 2012 15:21:18 -0500
> >> Michael Roth <mdroth@linux.vnet.ibm.com> wrote:
> >>
> >>> JSON numbers can be interpreted as either integers or floating point
> >>> values depending on their representation. As a result, QMP input visitor
> >>> might visit a QInt when it was expecting a QFloat, so add handling to
> >>> account for this.
> >>>
> >>> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> >>> ---
> >>>  qapi/qmp-input-visitor.c |    9 +++++++--
> >>>  1 files changed, 7 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/qapi/qmp-input-visitor.c b/qapi/qmp-input-visitor.c
> >>> index 4cdc47d..bc91134 100644
> >>> --- a/qapi/qmp-input-visitor.c
> >>> +++ b/qapi/qmp-input-visitor.c
> >>> @@ -246,13 +246,18 @@ static void qmp_input_type_number(Visitor *v, double *obj, const char *name,
> >>>      QmpInputVisitor *qiv = to_qiv(v);
> >>>      QObject *qobj = qmp_input_get_object(qiv, name);
> >>>  
> >>> -    if (!qobj || qobject_type(qobj) != QTYPE_QFLOAT) {
> >>> +    if (!qobj || (qobject_type(qobj) != QTYPE_QFLOAT &&
> >>> +        qobject_type(qobj) != QTYPE_QINT)) {
> >>>          error_set(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
> >>>                    "double");
> >>
> >> s/double/number
> >>
> >> It's also important to note that migrate_set_downtime is (positively) affected
> >> by this change. Today, it only accepts a double, eg.:
> >>
> >> { "execute": "migrate_set_downtime", "arguments": { "value": 1 } }
> >> {
> >>     "error": {
> >>         "class": "InvalidParameterType", 
> >>         "desc": "Invalid parameter type for 'value', expected: double", 
> >>         "data": {
> >>             "name": "value", 
> >>             "expected": "double"
> >>         }
> >>     }
> >> }
> >>
> >> That's a bug (as it's documented to accept a number) and this patch fixes it.
> >> There's an interface change, but I think it won't cause problems in practice.
> >>
> >> Please, fix the error message above and would be nice to get this (and patch
> >> 02/07) as a separate series for 1.1.
> > 
> > Hmm, this is kinda awkward because I don't think we can change it without
> > breaking any trees based off qom-next.
> 
> That's no problem at all, it is announced as rebasing and I have scripts
> in place to pull and recursively rebase all my QOM branches.
> 
> For such a trivial textual change I can even fix it up manually. :)
> 
> Since Luiz is now taking care of this one I will simply drop it from my
> qom-1.1 branch to avoid any confusion.

That'll work, thanks.

Luiz, I'll send a separate patch shortly with the error msg fixed.

> 
> Andreas
> 
> > Since the error msg predates the bug fix (it just becomes more obviously
> > wrong as a result of the fix), can you pull these commits as is into your
> > QMP tree?
> > 
> > In the meantime I can send another patch, based on qom-next or qmp, that
> > fixes the error msg. We can then get all 3 into 1.1/master via QMP tree, and I
> > think qom-next should still merge cleanly back into master after 1.1
> > 
> >>
> >>
> >>>          return;
> >>>      }
> >>>  
> >>> -    *obj = qfloat_get_double(qobject_to_qfloat(qobj));
> >>> +    if (qobject_type(qobj) == QTYPE_QINT) {
> >>> +        *obj = qint_get_int(qobject_to_qint(qobj));
> >>> +    } else {
> >>> +        *obj = qfloat_get_double(qobject_to_qfloat(qobj));
> >>> +    }
> >>>  }
> >>>  
> >>>  static void qmp_input_start_optional(Visitor *v, bool *present,
> 
> -- 
> SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
> GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg
>