[libvirt] [PATCH] virsh: Error prompt if one passes negative value for scheduler setting

[Osier Yang]

于 2011年01月28日 23:33, Eric Blake 写道:
> On 01/28/2011 05:11 AM, Osier Yang wrote:
>> 于 2011年01月28日 20:02, Daniel P. Berrange 写道:
>>> On Fri, Jan 28, 2011 at 07:53:44PM +0800, Osier Yang wrote:
>>>> As cgroup doesn't allow one writes negative into files like cpu.shares,
>>>> (e.g. echo -1>   /cgroup/cpu/libvirt/qemu/rhel6/cpu.shares), user will be
>>>> confused if libvirt accepts negative value and converts it into unsigned
>>>> int (or long int, etc) silently.
>
> But strtoul() is explicitly documented as accepting -1 as shorthand for
> ULONG_MAX, and as a command-line convenience, I much prefer that
> shorthand over 18446744073709551615.  I don't see this as confusing.
>
>>>
>>> Surely this check should be done inside  virStrToLong_{ui,ul,ull}
>
> If we want to be sticklers about reject '-' and module 2^32 (2^64)
> wraparound, then yes, virStrToLong_u* would be the place to do it.  But
> I'm not convinced that this is a good change.

I'm afraid changing on virStrToLong_u* will affect other codes, pretty
codes use them.

>
>> Is there some codes that expects virStrToLong_{ui,ul,ull} to convert
>> the negative to {ui, ul, ull}?
>
> Probably, given the above arguments about -1 being useful shorthand for
> the maximum value.
>

Yeah, so are you agreed with danpb? making changes on docs?

Regards
Osier