Date: Thu, 17 Apr 2003 08:08:03 -0500 From: "Jacques A. Vidrine" <nectar@FreeBSD.org> To: Munechika Sumikawa <sumikawa@ebina.hitachi.co.jp> Cc: src-committers@FreeBSD.org Subject: Re: cvs commit: src/lib/libipsec pfkey_dump.c Message-ID: <20030417130803.GA99068@madman.celabo.org> In-Reply-To: <20030417.082357.81502723.sumikawa@ebina.hitachi.co.jp> References: <200304161121.h3GBLDhJ040405@repoman.freebsd.org> <20030416124657.GD72501@madman.celabo.org> <20030417.082357.81502723.sumikawa@ebina.hitachi.co.jp>
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On Thu, Apr 17, 2003 at 08:23:57AM +0000, Munechika Sumikawa wrote:
> nectar> These sizes seem arbitrary. Previously, at 10 bytes, they were just a
> nectar> bit too small to hold the representation of the largest 32-bit
> nectar> unsigned integer. Now at 20 bytes, they are just a bit too small to
> nectar> hold the representation of the largest 64-bit unsigned integer. This
> nectar> seems sloppy. (As does using a 128 byte buffer to hold the result of
> nectar> concatenating two 20 byte buffers.)
>
> You are right. I've changed to 128 bytes.
Er, that wasn't quite my point :-) My point was that the buffer should
be sized correctly (rather than fudged), such as
char prefbuf[] = "/4294967296";
/* OR */
char prebuf[12];
or whatever you expect the maximum integer to be. [Isn't this a
network prefix? Surely 3 digits is sufficient?]
It just seems like a lot of wastage, but of course it isn't really
important.
> It can be used until we
> support 512bit CPU :-)
Actually 128 bytes is just big enough to hold a NUL-terminated string
representation of a 421-bit unsigned integer. You need 156 bytes for
512 bits :-)
Also, these two 128 byte buffers are still being concatenated into a
single 128 byte buffer, so on average you have room for about 209 bits
:-)
Cheers,
--
Jacques A. Vidrine <nectar@celabo.org> http://www.celabo.org/
NTT/Verio SME . FreeBSD UNIX . Heimdal Kerberos
jvidrine@verio.net . nectar@FreeBSD.org . nectar@kth.se
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