netdev - Re: [PATCH] skbuff: make skb_put

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Message-ID: <1497565276.2518.16.camel@sipsolutions.net>
Date:   Fri, 16 Jun 2017 00:21:16 +0200
From:   Johannes Berg <johannes@...solutions.net>
To:     Joe Perches <joe@...ches.com>, David Miller <davem@...emloft.net>
Cc:     netdev@...r.kernel.org
Subject: Re: [PATCH] skbuff: make skb_put_zero() return void

On Thu, 2017-06-15 at 15:17 -0700, Joe Perches wrote:

> I suggest changing those to skb_put_char(skb, char)

That might be something to think of, but you can't really know for sure
that they're not using len > 1 and don't yet care about the other bytes
or something. That'd probably be another bug, but ... dunno

And anyway, I think

*(u8 *)skb_put(skb, 1) = c;

isn't really that bad. Obviously that could be converted further to
skb_put_char(), using a simple spatch:

@@
expression SKB, C;
@@
- *(u8 *)skb_put(SKB, 1) = C;
+ skb_put_char(SKB, C);


> Here's a script that does the conversion.
> 
> $ /usr/bin/git grep -P --name-only
> "\*\s*skb_put\s*\(\s*([\w\.\[\]\>\-]+)\s*,\s*1\s*\)\s*=\s*([^;]+);" |
> \
>   xargs perl -p -i -e 's/\*\s*skb_put\s*\(\s*([\w\.\[\]\>\-
> ]+)\s*,\s*1\s*\)\s*=\s*([^;]+);/skb_put_char(\1, \2);/'

Uh, I think you're using the wrong tool for the job :-)

johannes