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Date: Fri, 16 Dec 2011 08:56:17 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [PATCH 1/8] qapi: fix NULL pointer dereference
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: kwolf@redhat.com, qemu-devel@nongnu.org

On 12/16/2011 08:49 AM, Paolo Bonzini wrote:
> On 12/16/2011 03:46 PM, Anthony Liguori wrote:
>>>
>>> Hmm, then we have to introduce NULL into QJson and visitors.
>>
>> Visitors assume that strings aren't nullable (which is actually true in
>> JSON and in QString).
>>
>> I also think that string properties shouldn't be nullable.
>
> Unfortunately, qdev string properties are nullable and there might well be
> examples in which empty and NULL are different. I'd rather not risk.
>
> But JSON actually has NULL, so not all is lost. I can introduce a nullable_str
> type in visitors (restricting structs and arrays should be fine, though).

I'd really prefer to stick to non-nullable strings as there is no obvious way to 
specify NULL in command line options.

What are the uses of null in qdev string properties?  I know you can't set a 
string to null since parse() doesn't have a null syntax.  So we're really just 
talking about an uninitialized state, right?

Regards,

Anthony Liguori

>
> Paolo
>