From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1NBWEI-0001up-KY
	for qemu-devel@nongnu.org; Fri, 20 Nov 2009 11:21:02 -0500
Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43)
	id 1NBWED-0001tI-Vu
	for qemu-devel@nongnu.org; Fri, 20 Nov 2009 11:21:02 -0500
Received: from [199.232.76.173] (port=44709 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1NBWED-0001t5-JP
	for qemu-devel@nongnu.org; Fri, 20 Nov 2009 11:20:57 -0500
Received: from mx1.redhat.com ([209.132.183.28]:20101)
	by monty-python.gnu.org with esmtp (Exim 4.60)
	(envelope-from <lcapitulino@redhat.com>) id 1NBWED-0002IM-4L
	for qemu-devel@nongnu.org; Fri, 20 Nov 2009 11:20:57 -0500
Date: Fri, 20 Nov 2009 14:20:43 -0200
From: Luiz Capitulino <lcapitulino@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 00/10]: QError v4
Message-ID: <20091120142043.7ea716b9@doriath>
In-Reply-To: <4B06BC3E.5060806@codemonkey.ws>
References: <1258487037-24950-1-git-send-email-lcapitulino@redhat.com>
	<m33a4bes1c.fsf@crossbow.pond.sub.org>
	<4B04383A.9050101@linux.vnet.ibm.com>
	<20091119023651.GA15128@shareable.org>
	<4B06BC3E.5060806@codemonkey.ws>
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Markus@gnu.org, kraxel@redhat.com, qemu-devel@nongnu.org, Armbruster <armbru@redhat.com>

On Fri, 20 Nov 2009 09:56:46 -0600
Anthony Liguori <anthony@codemonkey.ws> wrote:

> Jamie Lokier wrote:
> > Anthony Liguori wrote:
> >   
> >> Markus Armbruster wrote:
> >>     
> >>> 3. It falls short of the requirement that clients can easily present a
> >>>   human-readable error description to their human users, regardless of
> >>>   whether they know the error or not.
> >>>  
> >>>       
> >> That's just incorrect.  We provide an example conversion table that's 
> >> akin to strerror() or a __repr__ for an exception in Python.
> >>     
> >
> > Markus refers to errors that the client does not know - i.e. when the
> > client is older than qemu, or is not in the same development branch if
> > it's a branched qemu.  Which means the client won't have a fully up to
> > date conversion table.

 What's the proper fix for this? I can only think of having QError on
library, which is what we're going to do, anyway.

> > Do you mean qemu provides it's current conversion table to the client
> > over the wire protocol?
> >   
> 
> (qemu) format_error "{'class': 'DeviceNotFound', 'data' : {'addr': 
> '00:11:22'} }"
> Device 0:11:22 is not present
> 
> Is what I'm thinking.  I don't think it's needed but it solves the 
> "problem".

 Couldn't the client print the error class for errors it doesn't
know about? Like:

"Unknown error: 'CloudProtocol'"

 I know this is bad, but seems a lot better than printing something
with the wrong locale (ie, 'desc').