[PATCH] wpa_supplicant: Allow user to disable short guard interval (SGI).

[Jouni Malinen]

On Tue, Dec 18, 2012 at 06:59:45AM -0800, Ben Greear wrote:
> On 12/18/2012 04:46 AM, Jouni Malinen wrote:
> > On Thu, Dec 13, 2012 at 09:30:26AM -0800, greearb at candelatech.com wrote:
> >>   	{ INT_RANGE(disable_ht40, -1, 1) },
> >> +	{ INT_RANGE(disable_sgi, -1, 1) },
> >>   	{ INT_RANGE(disable_max_amsdu, -1, 1) },
> >
> > Though, I changed that range to 0..1 since -1 did not seem to make sense
> > for it. I'd assume that disable_ht40 range is also incorrect, i.e., only
> > the A-MSDU parameters use -1.
> 
> My intention was to have -1 mean 'don't set', ie don't set the mask for it.

That's what disable_max_amsdu does. However, wpa_set_disable_ht40() and
wpa_set_disable_sgi() does not have any special case for -1 and as such,
that would be interpreted as disabled rather than don't set.

> I'm not sure that matters all that much, we could just as easily
> default to enabled.

We do exactly that.. disable_ht40/sgi are set to 0 by default which
means those are enabled. disable_ht40 could potentially be set to -1 in
the configuration and that would result in HT40 being disabled. With my
change for the disable_sgi range, this confusing value would be rejected
by configuration parser.

-- 
Jouni Malinen                                            PGP id EFC895FA