Re: [Qemu-devel] [PATCH RFC 2/6] qapi: use qemu_strtod() in string-input-visitor

[Eric Blake <eblake@redhat.com>]

On 11/15/18 5:09 AM, David Hildenbrand wrote:

>> Three more: in qobject-input-visitor.c's
>> qobject_input_type_number_keyval(),
> 
> This one is interesting, as it properly bails out when parsing "inf"
> (via isFinite()). - should we do the same for the string input visitor?
> 
> Especially, should we forbid "inf" and "NaN" in both scenarios?

JSON can't represent non-finite doubles. Internally, we might be able to 
use them, but you have a point that consistently rejecting non-finite in 
all of our QAPI parsers makes it easier to reason about the code base 
(the command line can't be used to inject a value not possible via QMP). 
So that makes sense to me.  qemu_strtod() shouldn't reject non-finite 
numbers (because it is useful for more than just qapi), but we could add 
a new qemu_strtod_finite() if that would help avoid duplication.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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