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From: Peter Maydell <peter.maydell@linaro.org>
Date: Thu, 22 Oct 2015 11:02:03 +0100
Message-ID: <CAFEAcA-1v6TLhHGCwp1afToVuJmbU3gvz4mse-f-WcLTWvtf1A@mail.gmail.com>
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Subject: Re: [Qemu-devel] [PATCH v2 03/16] sockets: allow port to be NULL
 when listening on IP address
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To: "Daniel P. Berrange" <berrange@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, Knut Omang <knuto@ifi.uio.no>, "Dr. David Alan Gilbert" <dgilbert@redhat.com>, QEMU Developers <qemu-devel@nongnu.org>

On 22 October 2015 at 10:43, Daniel P. Berrange <berrange@redhat.com> wrote:
> For reasons I don't understand, it appears that even string
> fields which are marked as optional get a 'has_XXX' flag,
> to distinguish betweeen a NULL string and an unset string.
> I struggle to imagine why we need this. It makes sense for
> integer/boolean types, but I would have thought just checking
> for NULL was sufficient for string types.

I think the argument here is pure consistency. *Every* optional
field should be implemented as has_fieldname (bool) plus fieldname
(actual value). Special casing string types because we happen
to have a special value we can use to indicate 'no string'
seems to me like it would cause more confusion than it would
be worth.

thanks
-- PMM