Re: [PATCH] core: dev: don't call BUG() on bad input

[Nicolas de Pesloüan]

Le 14/02/2011 13:23, Vasiliy Kulikov a écrit :
> Hi Nicolas,

Hi Vasiliy,

> On Mon, Feb 14, 2011 at 13:16 +0100, Nicolas de Pesloüan wrote:
> > > -	BUG_ON(strlen(name)>= sizeof(dev->name));
> > > +	if (strnlen(name, sizeof(dev->name))>= sizeof(dev->name)) {
>
> Ehh...  Space after ")" is needed :)

:-D

> > "size_t strnlen(const char *s, size_t maxlen) : The strnlen()
> > function returns strlen(s), if that is less than maxlen, or maxlen
> > if there is no '\0' character among the first maxlen characters
> > pointed to by s."
> >
> > How can strnlen(name, sizeof(dev->name)) be greater than sizeof(dev->name)?
> >
> > Shouldn't it be "if (strnlen(name, sizeof(dev->name)) == sizeof(dev->name))" instead?
>
> Not a big deal, but MO it's better to guard from everything that
> is not a good input by negating the check.  strnlen()<  sizeof() is OK,
> strnlen()>= sizeof() is bad.  Is "==" more preferable for net/ coding style?

Agreed, both cannot cause any troubles. == is supposed to be better from the API point of view, but 
>= is probably more readable.

	Nicolas.
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