From mboxrd@z Thu Jan  1 00:00:00 1970
From: johannes@sipsolutions.net (Johannes Berg)
Date: Fri, 21 Apr 2017 23:19:32 +0200
Subject: [Cocci] modifying array initializers?
In-Reply-To: <alpine.DEB.2.20.1704212131230.3038@hadrien>
References: <1492780343.2564.4.camel@sipsolutions.net>
 <alpine.DEB.2.20.1704211607100.3038@hadrien>
 <1492800782.19290.1.camel@sipsolutions.net>
 <alpine.DEB.2.20.1704212131230.3038@hadrien>
Message-ID: <1492809572.24783.1.camel@sipsolutions.net>
To: cocci@systeme.lip6.fr
List-Id: cocci@systeme.lip6.fr


> > Sounds like it doesn't like to add multiple things here, let me
> > think about how to work around that.
> 
> If you don't find a solution, send back the rule and the code that
> causes trouble, and I will take a look.

I tried for a while now, but didn't find one. I think the problem is
that it's evaluating all of these things at once, and then it doesn't
know how to place two of the new wrap_fn functions when they both
should go before nl80211_ops[].

The code is net/wireless/n80211.c, and my current version of the
spatch, as you suggested, is this:


@@
identifier fn;
fresh identifier wrap_fn = "_wrap_" ## fn;
@@
+static int wrap_fn(struct sk_buff *skb, struct genl_info *info)
+{
+       return fn(skb, info);
+}
+
static struct genl_ops nl80211_ops[] = {
        ...,
        {
-               .doit = fn,
+               .doit = wrap_fn,
                ...
        },
        ...
};


It *does* work to match multiple .doit instances now, but it seems to
get confused when trying to place more than one wrap_fn right before
nl80211_ops[].

I tried pulling it out into a separate rule, attaching it to some other
token, e.g. after nl80211_post_doit(), but I can't seem to get that to
work.

johannes