Re: [Outreachy kernel] [PATCH] Staging: rtl8192u: ieee80211_rx: Remove unnecessary code

[Sudip Mukherjee <sudipm.mukherjee@gmail.com>]

On Thu, Oct 15, 2015 at 12:22:35PM +0530, Shivani Bhardwaj wrote:
> On Thu, Oct 15, 2015 at 12:20 PM, Sudip Mukherjee
> <sudipm.mukherjee@gmail.com> wrote:
> > On Wed, Oct 14, 2015 at 10:48:50PM +0530, Shivani Bhardwaj wrote:
> >> The variable frame_authorized is declared and mentioned in the code but
> >> is not used anywhere so, it should be removed. Also, two case statements
> >> are merged by removing an extra break.
> > <snip>
> >> @@ -1106,10 +1105,7 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
> >>               switch (hostap_handle_sta_rx(ieee, dev, skb, rx_stats,
> >>                                            wds != NULL)) {
> >>               case AP_RX_CONTINUE_NOT_AUTHORIZED:
> >> -                     frame_authorized = 0;
> >> -                     break;
> >>               case AP_RX_CONTINUE:
> >> -                     frame_authorized = 1;
> >>                       break;
> >
> > Just a doubt, it now becomes:
> >         case AP_RX_CONTINUE_NOT_AUTHORIZED:
> >         case AP_RX_CONTINUE:
> >                 break;
> >
> > If these two cases are not doing anything then what is the use of having
> > them here in the switch-case?
> >
> > regards
> > sudip
> 
> Because we don't have a default case here and the variable in switch
> might still get these values based on some other code.

I think default case is to handle all cases which are not given by case
statement. What will happen if variable gets these values but these
cases are not mentioned? switch-case will see that these cases are not
mentioned and will exit the switch-case. In the situation where these
cases are mentioned, switch-case will see these cases exist, will come
to these cases and breaks out of switch-case.
Am I understanding anything wrong here?

regards
sudip