From owner-freebsd-current@FreeBSD.ORG  Wed Sep  8 16:39:08 2010
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To: mdf@FreeBSD.org
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Wed, 08 Sep 2010 08:51:57 MST."
	<AANLkTikO1v7YMFKVZkHZDmurcyfq0QbTkPxG=LNBdKSp@mail.gmail.com> 
Date: Wed, 08 Sep 2010 16:39:06 +0000
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Cc: freebsd-current@FreeBSD.org
Subject: Re: deprecating sprintf(9) 
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In message <AANLkTikO1v7YMFKVZkHZDmurcyfq0QbTkPxG=LNBdKSp@mail.gmail.com>, mdf@
FreeBSD.org writes:

>It seems like a large project, but OTOH sprintf(9) is mighty unsafe in
>the kernel.

Well, it is only unsafe if people used it without knowing what they
are doing, so I think a wholesale automated replacement is both
unwarranted and inadvisable.

I can recommend the following macro for the static buffer cases, it
checks if people know what they are doing with an assert.

#define bprintf(buf, fmt, ...)                                          \
        do {                                                            \
                assert(snprintf(buf, sizeof buf, fmt, __VA_ARGS__)      \
                    < sizeof buf);                                      \
        } while (0)

Poul-Henning

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.