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From: Jose M Rodriguez <josemi@freebsd.jazztel.es>
To: Marcel Moolenaar <marcel@xcllnt.net>
Date: Tue, 26 Apr 2005 22:22:40 +0200
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cc: freebsd-current@freebsd.org
cc: Jose M Rodriguez <josemi@freebsd.jazztel.es>
Subject: Re: rigth crc32 implementation
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El Martes, 26 de Abril de 2005 21:42, Marcel Moolenaar escribi=F3:
> On Tue, Apr 26, 2005 at 11:43:54AM +0200, Jose M Rodriguez wrote:
> > My first think was use the libkern based one, but I found:
> > sys/linkern/crc32.c
> >
> > - the code may not be endian safe.
>
> It operates on bytes, so it's endian-safe. Note that the uint32_t
> that's returned is not subject to endianness issues: it's always
> in the native byte order. The caller of crc32 needs to byteswap
> if it needs to compare this integral with a CRC that's not in
> the native byte order.
>

Yes, but this code come from a previous reduction: calculate the table=20
from a xor/shift bit oriented alg.

Looking at sys/net/if_ethersubr.c ether_crc32_be() & ether_crc32_le(), I=20
became to doubt if we need two tables, with bitesex based #ifs.

=2D-
  josemi