strtou(3) handling of negative input

[Alejandro Colomar]

Hi Bruno,

On Thu, Mar 20, 2025 at 12:12:10AM +0100, Alejandro Colomar wrote:
> > At the same time, disallowing a leading '-' sign
> > is a benefit as well. I consider it a misfeature that strtoul() parses
> > "-3" successfully and returns ULONG_MAX-2, which was most certainly
> > not intended by the user.
> 
> Agree; it is a misfeature.  In my API a2i(), when the type passed in the
> first parameter is an unsigned type, negative values are rejected.
> 
> I wonder if there's any legitimate user of that misfeature.  I didn't
> want to rule it out from a fundamental API just because I can't think of
> a good use of it.
> 
> Maybe since we have people from many systems here, anyone who has even
> seen a good use of strtoul(3) parsing negative values into an unsigned
> type can comment.  Maybe if we don't hear about it, we could consider it
> useless and tighten it?  Especially for an API that has explicit range
> checks.
> 
> Would NetBSD be open to changing the implementation of strtou(3) to
> reject negative input?

I have filed a bug in NetBSD for reforming strtou(3):
<https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=59198>

Let's see what they think about it.


Cheers,
Alex

-- 
<https://www.alejandro-colomar.es/>
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