From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= <roger.pau@citrix.com>
Subject: Re: [PATCH 2/2] libxl: fix UUID usage on FreeBSD
Date: Fri, 15 Jan 2016 16:11:31 +0100
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To: Ian Campbell <ian.campbell@citrix.com>, xen-devel@lists.xenproject.org
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El 15/01/16 a les 11.26, Ian Campbell ha escrit:
> On Tue, 2016-01-12 at 14:14 +0100, Roger Pau Monne wrote:
>> libxl makes the assumtion that libxl_uuid == uuid_t,
> 
> ("assumption")
> 
>>  and that uuid_t can be
>> freely used as a byte array. This is not true on FreeBSD (and NetBSD
>> too, not sure about other BSD UUID implementations), where the internals
>> of
>> uuid don't match what libxl expects as a byte array because of endianness
>> issues.
>>
>> Fix this by converting the libxl_uuid type to a struct with an internal
>> uuid_t field and a byte-array. Also introduce a new function that should
>> be
>> used in order to load a byte array into a uuid_t struct.
> 
> Do we really need to keep both the uuid_t and the byte-array representation
> around? It looks to me as if we only really need the byte-array form, which
> might then involve changing various uses of uuid_* internally to just be
> mem*.

Yes, we can remove the uuid_t from libxl_uuid, but this is AFAICT a
structure that belongs to the stable API. My current change keeps the
same layout by turning the union into a struct, but without changing the
fields.

Roger.