Horton

Re: UCT (Re: pgsql: Update time zone data files to tzdata release 2019a.)

Andrew Gierth <andrew@tao11.riddles.org.uk>

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From: Andrew Gierth <andrew@tao11.riddles.org.uk>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Christoph Berg <myon@debian.org>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2019-06-14T22:14:09Z
Lists: pgsql-hackers

Attachments

>>>>> "Andrew" == Andrew Gierth <andrew@tao11.riddles.org.uk> writes:
>>>>> "Tom" == Tom Lane <tgl@sss.pgh.pa.us> writes:

 >>> This isn't good enough, because it still picks "UCT" on a system
 >>> with no /etc/localtime and no TZ variable. Testing on HEAD as of
 >>> 3da73d683 (on FreeBSD, but it'll be the same anywhere else):

 Tom> [ shrug... ]  Too bad.  I doubt that that's a common situation anyway.

 Andrew> I'm also reminded that this applies also if the /etc/localtime
 Andrew> file is a _copy_ of the UTC zonefile rather than a symlink,
 Andrew> which is possibly even more common.

And testing shows that if you select "UTC" when installing FreeBSD, you
indeed get /etc/localtime as a copy not a symlink, and I've confirmed
that initdb picks "UCT" in that case.

So here is my current proposed fix.

-- 
Andrew (irc:RhodiumToad)

Commits

  1. Tweak our special-case logic for the IANA "Factory" timezone.

  2. Avoid choosing "localtime" or "posixrules" as TimeZone during initdb.

  3. Prefer timezone name "UTC" over alternative spellings.

  4. Attempt to identify system timezone by reading /etc/localtime symlink.

  5. Update time zone data files to tzdata release 2019a.