Re: [PATCH 4/5] rtl8712: replace min with min_t

[Przemo Firszt <przemo@firszt.eu>]

Dnia 2012-12-10, pon o godzinie 12:41 +0300, Dan Carpenter pisze:
> On Sun, Dec 09, 2012 at 10:15:09AM +0000, Przemo Firszt wrote:
> > A clean up change suggested by checkpatch.pl
> > 
> > Signed-off-by: Przemo Firszt <przemo@firszt.eu>
> > ---
> >  drivers/staging/rtl8712/rtl871x_ioctl_linux.c | 6 ++----
> >  1 file changed, 2 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/staging/rtl8712/rtl871x_ioctl_linux.c b/drivers/staging/rtl8712/rtl871x_ioctl_linux.c
> > index cdb51d7..b131b61 100644
> > --- a/drivers/staging/rtl8712/rtl871x_ioctl_linux.c
> > +++ b/drivers/staging/rtl8712/rtl871x_ioctl_linux.c
> > @@ -188,8 +188,7 @@ static inline char *translate_scan(struct _adapter *padapter,
> >  	/* Add the ESSID */
> >  	iwe.cmd = SIOCGIWESSID;
> >  	iwe.u.data.flags = 1;
> > -	iwe.u.data.length = (u16)min((u16)pnetwork->network.Ssid.SsidLength,
> > -			    (u16)32);
> > +	iwe.u.data.length = min_t(u16, pnetwork->network.Ssid.SsidLength, 32);
> 
> pnetwork->network.Ssid.SsidLength is a u32 so it would be better to
> not truncate the upper bits away.  It's not going to cause a
> problem, but its slightly messy.
> 
> This is a common problem where people take the type of
> iwe.u.data.length and cast to that instead of considering the types
> for the data they are comparing.
> 
Dan,
Thanks for the comment!

iew.u.data.length is __u16

min_t is defined as:
#define min_t(type, x, y) ({                    \
        type __min1 = (x);                      \
        type __min2 = (y);                      \
        __min1 < __min2 ? __min1: __min2; })

If I understand you correctly I should use this:

iwe.u.data.length = min_t(u32, pnetwork->network.Ssid.SsidLength, 32);

the result of min_t is u32, but iwe.u.data.lenght is __u16

Is that correct?
-- 
Kind regards,
Przemo Firszt