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Re: Ev2: providing checksums of files Re: svn commit: r1241733 - /subversion/trunk/subversion/libsvn_delta/compat.c

From: Hyrum K Wright <hyrum.wright_at_wandisco.com>
Date: Thu, 9 Feb 2012 13:16:13 -0600

On Thu, Feb 9, 2012 at 1:05 PM, Daniel Shahaf <danielsh_at_elego.de> wrote:
> Hyrum K Wright wrote on Thu, Feb 09, 2012 at 12:54:50 -0600:
>> (I'll also note that we actually *do* have a checksum by this point,
>> only it is the md5 provided by close_file(), and Ev2 uses sha1s
>> exclusively, so we have to recalculate.  I suspect this will be a
> Only sha1?  It allows neither md5 nor sha256?  Why?

"Convention" would be my initial response. It makes much more sense
to standardize checksum kinds across the system than to have a mixed
environment. Any checksum can help detect corruption, but being able
to answer the question "is this content the same as that content?" is
much more difficult in a mixed-checksum environment. sha1 felt like a
reasonable choice[1].

I could be overestimating the negatives, though. What reasons do you
suppose we *should* allow arbitrary checksum types?


[1] Though, given the timeline of Ev2 and the proposed timeline for
sha3, I'm really interested in the possibility of using sha3 when
standardized, throughout *all* of Subversion. (But that's a
completely separate discussion.)

uberSVN: Apache Subversion Made Easy
Received on 2012-02-09 20:16:46 CET

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