Re: [Qemu-devel] [PATCH v2 1/4] hw/block/fdc: Replace error_setg(&error_abort) by assert()

[John Snow <jsnow@redhat.com>]

On 06/08/2018 02:05 AM, Markus Armbruster wrote:
> John Snow <jsnow@redhat.com> writes:
> 
>> On 06/07/2018 10:46 AM, Philippe Mathieu-Daudé wrote:
>>> Use assert() instead of error_setg(&error_abort),
>>> as suggested by the "qapi/error.h" documentation:
>>>
>>>     Please don't error_setg(&error_fatal, ...), use error_report() and
>>>     exit(), because that's more obvious.
>>>     Likewise, don't error_setg(&error_abort, ...), use assert().
>>>
>>> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>>> ---
>>>  hw/block/fdc.c | 9 +--------
>>>  1 file changed, 1 insertion(+), 8 deletions(-)
>>>
>>> diff --git a/hw/block/fdc.c b/hw/block/fdc.c
>>> index cd29e27d8f..7c1c57f57f 100644
>>> --- a/hw/block/fdc.c
>>> +++ b/hw/block/fdc.c
>>> @@ -396,16 +396,9 @@ static int pick_geometry(FDrive *drv)
>>>                             nb_sectors,
>>>                             FloppyDriveType_str(parse->drive));
>>>          }
>>> +        assert(type_match != -1 && "misconfigured fd_format");
>>>          match = type_match;
>>>      }
>>> -
>>> -    /* No match of any kind found -- fd_format is misconfigured, abort. */
>>> -    if (match == -1) {
>>> -        error_setg(&error_abort, "No candidate geometries present in table "
>>> -                   " for floppy drive type '%s'",
>>> -                   FloppyDriveType_str(drv->drive));
>>> -    }
>>> -
>>>      parse = &(fd_formats[match]);
>>>  
>>>   out:
>>>
>>
>> Truthfully sad to see the lipstick go, because this is my pig.
>> Oh well, it doesn't matter. Not really, anyway.
>>
>> ACK
> 
> There's still a bit of lipstick in assert()'s argument.
> 
> v1 has the error_report() lipstick.  Would you like me to merge that one
> instead?  Your pig, your choice :)
> 

In the end I trust your judgement. I like the more verbose error message
because it tells you precisely what's going on. I like the assert
because it tells you WHERE in the code you've messed up.

I am often very keen on making things more usable and less tersely
worded. I think you favor some of the same things, but with years more
experience than I have.

So I defer to you; after all -- they're just pigs :)

--js