RFC: small syscons and kbd patch

[Maksim Yevmenkin]

On Thu, Dec 4, 2008 at 3:33 AM, Eygene Ryabinkin <rea-fbsd at codelabs.ru> wrote:
> Garrett, good day.
>
> Thu, Dec 04, 2008 at 03:24:28AM -0800, Garrett Cooper wrote:
>> On Tue, Dec 2, 2008 at 5:01 PM, Maksim Yevmenkin
>>      Why are you double and triple negating on this line?
>> +     return (atomic_cmpset_acq_int(&kbd->kb_locked, !!!on, !!on));
>
> Double negation is easy -- !!N = 1 for int N != 0, so it is the way to
> turn N != 0 to one.

yep, that was the idea.

>  Triple negation?  I am out of guesses, because it
> seems redundant to me: !0 = 1, !5 = 0, so adding another two negations
> is seem to be worthless.

well, that's just silly typo (blame my sticky fingers). you are
correct single negation should work just as good :)

thanks for catching this guys, i fixed it.

thanks,
max


> --
> Eygene
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