Re: [Qemu-devel] [PATCH 00/10]: QError v4

[Alexander Graf]

On 24.11.2009, at 12:55, Luiz Capitulino wrote:

> On Mon, 23 Nov 2009 14:50:05 +0100
> Alexander Graf <address@hidden> wrote:
> 
>> 
>> Am 23.11.2009 um 14:34 schrieb Luiz Capitulino <address@hidden>:
>> 
>>> On Mon, 23 Nov 2009 07:11:53 -0600
>>> Anthony Liguori <address@hidden> wrote:
>>> 
>>>> Luiz Capitulino wrote:
>>>>> On Sun, 22 Nov 2009 10:08:16 -0600
>>>>> Anthony Liguori <address@hidden> wrote:
>>>>> 
>>>>> 
>>>>>> I'm certainly willing to consider alternative ways to do qmp_error 
>>>>>> () but
>>>>>> taking a free form string is not an option in my mind. It goes  
>>>>>> against
>>>>>> the fundamentals of what we're trying to build with QMP.
>>>>>> 
>>>>> 
>>>>> Agreed.
>>>>> 
>>>>> 
>>>>>> So if you're opposed to structured error data, just having
>>>>>> qmp_error(error_code) is a reasonable alternative. I don't think  
>>>>>> it's
>>>>>> the right thing to do, but I think it's still within the spirit  
>>>>>> of the
>>>>>> goals of QMP.
>>>>>> 
>>>>> 
>>>>> You mean, we would have calls like:
>>>>> 
>>>>> qemu_error_new(error_code, 'device '%s' not found', name);
>>>>> 
>>>> 
>>>> Except drop the 'device %s not found' bit.
>>> 
>>> We would need a table to have the strings for the user protocol
>>> then. Not having the table is a key point in Markus's argument,
>>> I guess.
>> 
>> We would need that for internationalization anyways, right?
>> 
>> Though I don't dislike the idea of passing a plain default syntax over  
>> the wire as a bonus / fallback. Especially for cases where the ui is  
>> older than qemu.
>> 
>> So why not have the table inside qemu do a lookup and send that as  
>> default format in addition to the error code (that should usually be  
>> used to find out the format)?
> 
> The current proposal does have a table, the argument against it is
> that we're making error reporting complex, as developers will have to
> edit more than one place to report errors.

So why not generate the table from the format strings? So in the code there 
would only be

qemu_error_new("device '%s' not found", name);

and some code parsing magic on commit would put that in the official table?


Alex