Re: Should we add crc32 in libpgport?

On Mon, Jan 16, 2012 at 8:09 PM, Daniel Farina <daniel@heroku.com> wrote:
> On Mon, Jan 16, 2012 at 4:56 PM, Daniel Farina <daniel@heroku.com> wrote:
>> I have been working with xlogdump and noticed that unfortunately it
>> cannot be installed without access to a postgres build directory,
>> which makes the exported functionality in src/include/utils/pg_crc.h
>> useless unless one has access to pg_crc.o -- which would only happen
>> if a build directory is lying around.  Yet, pg_crc.h is *installed* in
>> server/utils, at least from my Debian package.   Worse yet, those crc
>> implementations are the same but ever-so-slightly different (hopefully
>> in an entirely non-semantically-important way).
>
> Out-of-order editing snafu.  "Worse yet, those crc implementations are
> the..."  should come after the note about there being two additional
> crc implementations in the postgres contribs.
>
> Looking back on it, it's obvious why those contribs had it in the
> first place: because they started external, and needed CRC, and the
> most expedient thing to do is include yet another implementation.  So
> arguably this problem has occurred three times: in xlogdump, and in
> pre-contrib versions of hstore, and ltree.  It's just the latter two
> sort of get a free pass by the virtue of having access to the postgres
> build directory as contribs in this day and age.

I think you make a compelling case.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company