On Wed, 2015-09-16 at 13:21 +0200, Rasmus Villemoes wrote:
> On Tue, Sep 15 2015, Andy Shevchenko <
> andriy.shevche...@linux.intel.com> wrote:
>
> > On Tue, 2015-09-15 at 15:55 +0200, Vitaly Kuznetsov wrote:
> > > +static __init void test_string_get_size_one(u64 size, u64
> > > blk_size,
> > > + const enum
> > > string_size_units units,
> > > + const char
> > > *exp_result)
> > > +{
> > > + char buf[16];
> > > +
> > > + string_get_size(size, blk_size, units, buf,
> > > sizeof(buf));
> > > + if (!memcmp(buf, exp_result, strnlen(exp_result,
> > > sizeof(buf)
> > > - 1) + 1))
> >
> > Actually you don't need to do this +- 1. Either you will have '\0'
> > or
> > not, it will be checked by memcmp() anyway.
> >
> > Thus,
> > memcmp(buf, exp_result, strnlen(exp_result, sizeof(buf))).
>
> Huh? How does that ensure that string_get_size put a '\0' at the
> right
> spot? We do need the comparison to also cover the terminating '\0' in
> exp_result.
Ah, you are right.
But seems we have length of the exp_result always smaller than buffer
size, so, would we change this to
memcmp(…, strlen(exp_result) + 1);
?
> [It would be nice if we could assert at compile-time that
> strlen(exp_result) < sizeof(buf).]
Interesting if BUILD_BUG_ON can help here. Can we use
sizeof(exp_result) since all of them are literal constants?
>
> > Perhaps one line comment here
> > /* Make sure that buf will be always NULL-terminated */
> >
> > > + buf[sizeof(buf) - 1] = '\0';
>
> <bikeshed>Could we pretty-please use different names for 0 the
> pointer
> and 0 the character, say in this case nul or NUL or '\0' or simply
> 0. Also, I don't see the value of the comment; that line is a totally
> standard idiom.</bikeshed>.
Got your point.
--
Andy Shevchenko <andriy.shevche...@linux.intel.com>
Intel Finland Oy
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