There's no functional change at all here, but I'm curious to see
whether this change successfully shuts up Coverity's warning about
a useless strcmp(), which appeared with the previous update.
Discussion: http://mm.icann.org/pipermail/tz/2020-October/029370.html
This changes zic's default output format from "-b fat" to "-b slim".
We were already using "slim" in v13/HEAD, so those branches drop
the explicit -b switch in the Makefiles. Instead, add an explicit
"-b fat" in v12 and before, so that we don't change the output file
format in those branches. (This is perhaps excessively conservative,
but we decided not to do so in a12079109, and I'll stick with that.)
Other non-cosmetic changes are to drop support for zic's long-obsolete
"-y" switch, and to ensure that strftime() does not change errno
unless it fails.
As usual with tzcode changes, back-patch to all supported branches.
We had two occurrences of "Mitteleuropäische Zeit" in Europe.txt,
though the corresponding entries in Default were spelled
"Mitteleuropaeische Zeit". Standardize on the latter spelling to
avoid questions of which encoding to use.
While here, correct a couple of other trivial inconsistencies between
the Default file and the supposedly-matching entries in the *.txt
files, as exposed by some checking with comm(1). Also, add BDST to
the Europe.txt file; it previously was only listed in Default.
None of this has any direct functional effect.
Per complaint from Christoph Berg. As usual for timezone data patches,
apply to all branches.
Discussion: https://postgr.es/m/20200716100743.GE3534683@msg.df7cb.de
I forgot that INT64_FORMAT can't be used with sscanf on Windows.
Use the same trick of sscanf'ing into a temp variable as we do in
some other places in zic.c.
The upstream IANA code avoids the portability problem by relying on
<inttypes.h>'s SCNdFAST64 macro. Once we're requiring C99 in all
branches, we should do likewise and drop this set of diffs from
upstream. For now, though, a hack seems fine, since we do not
actually care about leapseconds anyway.
Discussion: https://postgr.es/m/4e5d1a5b-143e-e70e-a99d-a3b01c1ae7c3@2ndquadrant.com
This absorbs a leap-second-related bug fix in localtime.c, and
teaches zic to handle an expiration marker in the leapseconds file.
Neither are of any interest to us (for the foreseeable future
anyway), but we need to stay more or less in sync with upstream.
Also adjust some over-eager changes in the README from commit 957338418.
I have no intention of making changes that require C99 in this code,
until such time as all the live back branches require C99. Otherwise
back-patching will get too exciting.
For the same reason, absorb assorted whitespace and other cosmetic
changes from HEAD into the back branches; mostly this reflects use of
improved versions of pgindent.
All in all then, quite a boring update. But I figured I'd get it
done while I was looking at this code.
DST law changes in Morocco and the Canadian Yukon.
Historical corrections for Shanghai.
The America/Godthab zone is renamed to America/Nuuk to reflect
current English usage; however, the old name remains available as a
compatibility link.
DST law changes in Fiji and Norfolk Island. Historical corrections
for Alberta, Austria, Belgium, British Columbia, Cambodia, Hong Kong,
Indiana (Perry County), Kaliningrad, Kentucky, Michigan, Norfolk
Island, South Korea, and Turkey.
pg_timezone_names() tries to avoid showing the "Factory" zone in
the view, mainly because that has traditionally had a very long
"abbreviation" such as "Local time zone must be set--see zic manual page",
so that showing it messes up psql's formatting of the whole view.
Since tzdb version 2016g, IANA instead uses the abbreviation "-00",
which is sane enough that there's no reason to discriminate against it.
On the other hand, it emerges that FreeBSD and possibly other packagers
are so wedded to backwards compatibility that they hack the IANA data
to keep the old spelling --- and not just that old spelling, but even
older spellings that IANA used back in the stone age. This caused the
filter logic to fail to suppress "Factory" at all on such platforms,
though the formatting problem is definitely real in that case.
To solve both problems, get rid of the hard-wired assumption about
exactly what Factory's abbreviation is, and instead reject abbreviations
exceeding 31 characters. This will allow Factory to appear in the view
if and only if it's using the modern abbreviation.
In passing, simplify the code we add to zic.c to support "zic -P"
to remove its now-obsolete hacks to not print the Factory zone's
abbreviation. Unlike pg_timezone_names(), there's no reason for
that code to support old/nonstandard timezone data.
Since we generally prefer to keep timezone-related behavior the
same in all branches, and since this is arguably a bug fix,
back-patch to all supported branches.
Discussion: https://postgr.es/m/3961.1564086915@sss.pgh.pa.us
Absorb commit e5e04c962a5d12eebbf867ca25905b3ccc34cbe0 from upstream
IANA code, in hopes of silencing warnings from MSVC about negating
a bool value.
Discussion: https://postgr.es/m/20190719035347.GJ1859@paquier.xyz
A large fraction of this diff is just due to upstream's somewhat
random decision to rename a bunch of internal variables and struct
fields. However, there is an interesting new feature in zic:
it's grown a "-b slim" option that emits zone files without 32-bit
data and other backwards-compatibility hacks. We should consider
whether we wish to enable that.
This corrects a small bug in zic that caused it to output an incorrect
year-2440 transition in the Africa/Casablanca zone.
More interestingly, zic has grown a "-r" option that limits the range of
zone transitions that it will put into the output files. That might be
useful to people who don't like the weird GMT offsets that tzdb likes
to use for very old dates. It appears that for dates before the cutoff
time specified with -r, zic will use the zone's standard-time offset
as of the cutoff time. So for example one might do
make install ZIC_OPTIONS='-r @-1893456000'
to cause all dates before 1910-01-01 to be treated as though 1910
standard time prevailed indefinitely far back. (Don't blame me for
the unfriendly way of specifying the cutoff time --- it's seconds
since or before the Unix epoch. You can use extract(epoch ...)
to calculate it.)
As usual, back-patch to all supported branches.
DST law changes in Palestine and Metlakatla.
Historical corrections for Israel.
Etc/UCT is now a backward-compatibility link to Etc/UTC, instead
of being a separate zone that generates the abbreviation "UCT",
which nowadays is typically a typo. Postgres will still accept
"UCT" as an input zone name, but it won't output it.
DST law changes in Kazakhstan, Metlakatla, and São Tomé and Príncipe.
Kazakhstan's Qyzylorda zone is split in two, creating a new zone
Asia/Qostanay, as some areas did not change UTC offset.
Historical corrections for Hong Kong and numerous Pacific islands.
This patch absorbs an upstream fix to "zic" for a recently-introduced
bug that made it output data that some 32-bit clients couldn't read.
Given the current source data, the bug only manifests in zones with
leap seconds, which we don't generate, so that there's no actual
change in our installed timezone data files from this. Still, in
case somebody uses our copy of "zic" to do something else, it seems
best to apply the fix promptly.
Also, update the README's notes about converting upstream code to
our conventions.
About half of this is purely cosmetic changes to reduce the diff between
our code and theirs, like inserting "const" markers where they have them.
The other half is tracking actual code changes in zic.c and localtime.c.
I don't think any of these represent near-term compatibility hazards, but
it seems best to stay up to date.
I also fixed longstanding bugs in our code for producing the
known_abbrevs.txt list, which by chance hadn't been exposed before,
but which resulted in some garbage output after applying the upstream
changes in zic.c. Notably, because upstream removed their old phony
transitions at the Big Bang, it's now necessary to cope with TZif files
containing no DST transition times at all.
DST law changes in Chile, Fiji, and Russia (Volgograd).
Historical corrections for China, Japan, Macau, and North Korea.
Note: like the previous tzdata update, this involves a depressingly
large amount of semantically-meaningless churn in tzdata.zi. That
is a consequence of upstream's data compression method assigning
unstable abbreviations to DST rulesets. I complained about that
to them last time, and this version now uses an assignment method
that pays some heed to not changing abbreviations unnecessarily.
So hopefully, that'll be better going forward.
In the IANA timezone code, tzparse() always tries to load the zone
file named by TZDEFRULES ("posixrules"). Previously, we'd hacked
that logic to skip the load in the "lastditch" code path, which we use
only to initialize the default "GMT" zone during GUC initialization.
That's critical for a couple of reasons: since we do not support leap
seconds, we *must not* allow "GMT" to have leap seconds, and since this
case runs before the GUC subsystem is fully alive, we'd really rather
not take the risk of pg_open_tzfile throwing any errors.
However, that still left the code reading TZDEFRULES on every other
call, something we'd noticed to the extent of having added code to cache
the result so it was only done once per process not a lot of times.
Andres Freund complained about the static data space used up for the
cache; but as long as the logic was like this, there was no point in
trying to get rid of that space.
We can improve matters by looking a bit more closely at what the IANA
code actually needs the TZDEFRULES data for. One thing it does is
that if "posixrules" is a leap-second-aware zone, the leap-second
behavior will be absorbed into every POSIX-style zone specification.
However, that's a behavior we'd really prefer to do without, since
for our purposes the end effect is to render every POSIX-style zone
name unsupported. Otherwise, the TZDEFRULES data is used only if
the POSIX zone name specifies DST but doesn't include a transition
date rule (e.g., "EST5EDT" rather than "EST5EDT,M3.2.0,M11.1.0").
That is a minority case for our purposes --- in particular, it
never happens when tzload() invokes tzparse() to interpret a
transition date rule string found in a tzdata zone file.
Hence, if we legislate that we're going to ignore leap-second data
from "posixrules", we can postpone the TZDEFRULES load into the path
where we actually need to substitute for a missing date rule string.
That means it will never happen at all in common scenarios, making it
reasonable to dynamically allocate the cache space when it does happen.
Even when the data is already loaded, this saves some cycles in the
common code path since we avoid a memcpy of 23KB or so. And, IMO at
least, this is a less ugly hack on the IANA logic than what we had
before, since it's not messing with the lastditch-vs-regular code paths.
Back-patch to all supported branches, not so much because this is a
critical change as that I want to keep all our copies of the IANA
timezone code in sync.
Discussion: https://postgr.es/m/20181015200754.7y7zfuzsoux2c4ya@alap3.anarazel.de
localtime.c's "struct state" is a rather large object, ~23KB. We were
statically allocating one for gmtsub() to use to represent the GMT
timezone, even though that function is not at all heavily used and is
never reached in most backends. Let's malloc it on-demand, instead.
This does pose the question of how to handle a malloc failure, but
there's already a well-defined error report convention here, ie
set errno and return NULL.
We have but one caller of pg_gmtime in HEAD, and two in back branches,
neither of which were troubling to check for error. Make them do so.
The possible errors are sufficiently unlikely (out-of-range timestamp,
and now malloc failure) that I think elog() is adequate.
Back-patch to all supported branches to keep our copies of the IANA
timezone code in sync. This particular change is in a stanza that
already differs from upstream, so it's a wash for maintenance purposes
--- but only as long as we keep the branches the same.
Discussion: https://postgr.es/m/20181015200754.7y7zfuzsoux2c4ya@alap3.anarazel.de
DST law changes in North Korea. Redefinition of "daylight savings" in
Ireland, as well as for some past years in Namibia and Czechoslovakia.
Additional historical corrections for Czechoslovakia.
With this change, the IANA database models Irish timekeeping as following
"standard time" in summer, and "daylight savings" in winter, so that the
daylight savings offset is one hour behind standard time not one hour
ahead. This does not change their UTC offset (+1:00 in summer, 0:00 in
winter) nor their timezone abbreviations (IST in summer, GMT in winter),
though now "IST" is more correctly read as "Irish Standard Time" not "Irish
Summer Time". However, the "is_dst" column in the pg_timezone_names view
will now be true in winter and false in summer for the Europe/Dublin zone.
Similar changes were made for Namibia between 1994 and 2017, and for
Czechoslovakia between 1946 and 1947.
So far as I can find, no Postgres internal logic cares about which way
tm_isdst is reported; in particular, since commit b2cbced9e we do not
rely on it to decide how to interpret ambiguous timestamps during DST
transitions. So I don't think this change will affect any Postgres
behavior other than the timezone-view outputs.
Discussion: https://postgr.es/m/30996.1525445902@sss.pgh.pa.us
The non-cosmetic changes involve teaching the "zic" tzdata compiler about
negative DST. While I'm not currently intending that we start using
negative-DST data right away, it seems possible that somebody would try
to use our copy of zic with bleeding-edge IANA data. So we'd better be
out in front of this change code-wise, even though it doesn't matter for
the data file we're shipping.
Discussion: https://postgr.es/m/30996.1525445902@sss.pgh.pa.us
DST law changes in Palestine and Antarctica (Casey Station). Historical
corrections for Portugal and its colonies, as well as Enderbury, Jamaica,
Turks & Caicos Islands, and Uruguay.
DST law changes in Brazil, Sao Tome and Principe. Historical corrections
for Bolivia, Japan, and South Sudan. The "US/Pacific-New" zone has been
removed (it was only a link to America/Los_Angeles anyway).
Traditionally IANA has distributed their timezone data in pure source
form, replete with extensive historical comments. As of release 2017c,
they've added a compact single-file format that omits comments and
abbreviates command keywords. This form is way shorter than the pure
source, even before considering its allegedly better compressibility.
Hence, let's distribute the data in that form rather than pure source.
I'm pushing this now, rather than at the next timezone database update,
so that it's easy to confirm that this data file produces compiled zic
output that's identical to what we were getting before.
Discussion: https://postgr.es/m/1915.1511210334@sss.pgh.pa.us
DST law changes in Fiji, Namibia, Northern Cyprus, Sudan, Tonga,
and Turks & Caicos Islands. Historical corrections for Alaska, Apia,
Burma, Calcutta, Detroit, Ireland, Namibia, and Pago Pago.
This is a trivial update containing only cosmetic changes. The point
is just to get back to being synced with an official release of tzcode,
rather than some ad-hoc point in their commit history, which is where
commit 47f849a3c left it.
This patch absorbs a few unreleased fixes in the IANA code.
It corresponds to commit 2d8b944c1cec0808ac4f7a9ee1a463c28f9cd00a
in https://github.com/eggert/tz. Non-cosmetic changes include:
TZDEFRULESTRING is updated to match current US DST practice,
rather than what it was over ten years ago. This only matters
for interpretation of POSIX-style zone names (e.g., "EST5EDT"),
and only if the timezone database doesn't include either an exact
match for the zone name or a "posixrules" entry. The latter
should not be true in any current Postgres installation, but
this could possibly matter when using --with-system-tzdata.
Get rid of a nonportable use of "++var" on a bool var.
This is part of a larger fix that eliminates some vestigial
support for consecutive leap seconds, and adds checks to
the "zic" compiler that the data files do not specify that.
Remove a couple of ancient compatibility hacks. The IANA
crew think these are obsolete, and I tend to agree. But
perhaps our buildfarm will think different.
Back-patch to all supported branches, in line with our policy
that all branches should be using current IANA code. Before v10,
this includes application of current pgindent rules, to avoid
whitespace problems in future back-patches.
Discussion: https://postgr.es/m/E1dsWhf-0000pT-F9@gemulon.postgresql.org
Pre-C99 platforms may lack <stdint.h> and thereby SIZE_MAX. We have
a couple of places using the hack "(size_t) -1" as a fallback, but
it wasn't universally available; which means the code added in commit
2e70d6b5e fails to compile everywhere. Move that hack to c.h so that
we can rely on having SIZE_MAX everywhere.
Per discussion, it'd be a good idea to make the macro's value safe
for use in #if-tests, but that will take a bit more work. This is
just a quick expedient to get the buildfarm green again.
Back-patch to all supported branches, like the previous commit.
Discussion: https://postgr.es/m/15883.1504278595@sss.pgh.pa.us
The upstream IANA code does not guard against null TM_ZONE pointers in this
function, but in our code there is such a check in the other pre-existing
use of t->tm_zone. We do have some places that set pg_tm.tm_zone to NULL.
I'm not entirely sure it's possible to reach strftime with such a value,
but I'm not sure it isn't either, so be safe.
Per Coverity complaint.
Fix oversight in commit af2c5aa88: if the shortcut open() doesn't work,
we need to reset fullname[] to be just the name of the toplevel tzdata
directory before we fall through into the pre-existing code. This failed
to be exposed in my (tgl's) testing because the fall-through path is
actually never taken under normal circumstances.
David Rowley, per report from Amit Kapila
Discussion: https://postgr.es/m/CAA4eK1LC7CaNhRAQ__C3ht1JVrPzaAXXhEJRnR5L6bfYHiLmWw@mail.gmail.com
tzparse() would attempt to load the "posixrules" timezone database file on
each call. That might seem like it would only be an issue when selecting a
POSIX-style zone name rather than a zone defined in the timezone database,
but it turns out that each zone definition file contains a POSIX-style zone
string and tzload() will call tzparse() to parse that. Thus, when scanning
the whole timezone file tree as we do in the pg_timezone_names view,
"posixrules" was read repetitively for each zone definition file. Fix
that by caching the file on first use within any given process. (We cache
other zone definitions for the life of the process, so there seems little
reason not to cache this one as well.) This probably won't help much in
processes that never run pg_timezone_names, but even one additional SET
of the timezone GUC would come out ahead.
An even worse problem for pg_timezone_names is that pg_open_tzfile()
has an inefficient way of identifying the canonical case of a zone name:
it basically re-descends the directory tree to the zone file. That's not
awful for an individual "SET timezone" operation, but it's pretty horrid
when we're inspecting every zone in the database. And it's pointless too
because we already know the canonical spelling, having just read it from
the filesystem. Fix by teaching pg_open_tzfile() to avoid the directory
search if it's not asked for the canonical name, and backfilling the
proper result in pg_tzenumerate_next().
In combination these changes seem to make the pg_timezone_names view
about 3x faster to read, for me. Since a scan of pg_timezone_names
has up to now been one of the slowest queries in the regression tests,
this should help some little bit for buildfarm cycle times.
Back-patch to all supported branches, not so much because it's likely
that users will care much about the view's performance as because
tracking changes in the upstream IANA timezone code is really painful
if we don't keep all the branches in sync.
Discussion: https://postgr.es/m/27962.1493671706@sss.pgh.pa.us
DST law changes in Chile, Haiti, and Mongolia. Historical corrections for
Ecuador, Kazakhstan, Liberia, and Spain.
The IANA crew continue their campaign to replace invented time zone
abbrevations with numeric GMT offsets. This update changes numerous zones
in South America, the Pacific and Indian oceans, and some Asian and Middle
Eastern zones. I kept these abbreviations in the tznames/ data files,
however, so that we will still accept them for input. (We may want to
start trimming those files someday, but I think we should wait for the
upstream dust to settle before deciding what to do.)
In passing, add MESZ (Mitteleuropaeische Sommerzeit) to the tznames lists;
since we accept MEZ (Mitteleuropaeische Zeit) it seems rather strange not
to take the other one. And fix some incorrect, or at least obsolete,
comments that certain abbreviations are not traceable to the IANA data.
zic no longer mishandles some transitions in January 2038 when it
attempts to work around Qt bug 53071. This fixes a bug affecting
Pacific/Tongatapu that was introduced in zic 2016e. localtime.c
now contains a workaround, useful when loading a file generated by
a buggy zic.
There are assorted cosmetic changes as well, notably relocation
of a bunch of #defines.
DST law changes in northern Cyprus (new zone Asia/Famagusta), Russia (new
zone Europe/Saratov), Tonga, Antarctica/Casey. Historical corrections for
Asia/Aqtau, Asia/Atyrau, Asia/Gaza, Asia/Hebron, Italy, Malta. Replace
invented zone abbreviation "TOT" for Tonga with numeric UTC offset; but
as in the past, we'll keep accepting "TOT" for input.
This is a trivial update (consisting in fact only in the addition of
a comment). The point is just to get back to being synced with an
official release of tzcode, rather than some ad-hoc point in their
commit history, which is where commit 1f87181e1 left it.
The workaround the IANA guys chose to get rid of the clang warning
we'd silenced in commit 23ed2ba81 turns out not to satisfy Coverity.
Go back to the previous solution, ie, remove the useless comparison
to SIZE_MAX. (In principle, there could be machines out there where
it's not useless because ptrdiff_t is wider than size_t. But the whole
thing is pretty academic anyway, as we could never approach this limit
for any sane estimate of the amount of data that zic will ever be asked
to work with.)
Also, s/lineno/lineno_t/g, because if we accept their decision to start
using "lineno" as a typedef, it is going to have very unpleasant
consequences in our next pgindent run. Noted that while fooling with
pltcl yesterday.
This patch absorbs some unreleased fixes for symlink manipulation bugs
introduced in tzcode 2016g. Ordinarily I'd wait around for a released
version, but in this case it seems like we could do with extra testing,
in particular checking whether it works in EDB's VMware build environment.
This corresponds to commit aec59156abbf8472ba201b6c7ca2592f9c10e077 in
https://github.com/eggert/tz.
Per a report from Sandeep Thakkar, building in an environment where hard
links are not supported in the timezone data installation directory failed,
because upstream code refactoring had broken the case of symlinking from an
existing symlink. Further experimentation also showed that the symlinks
were sometimes made incorrectly, with too many or too few "../"'s in the
symlink contents.
Back-patch of commit 1f87181e12.
Report: <CANFyU94_p6mqRQc2i26PFp5QAOQGB++AjGX=FO8LDpXw0GSTjw@mail.gmail.com>
Discussion: http://mm.icann.org/pipermail/tz/2016-November/024431.html
I broke this in commit f3094920a. Apparently it's dead code anyway,
at least as far as our buildfarm is concerned (and the upstream IANA
code doesn't worry at all about symlink() not being present).
But as long as the rest of our code is willing to guard against not
having symlink(), this should too. Noted while investigating a
tangentially-related complaint from Sandeep Thakkar.
Back-patch to keep branches in sync.
This absorbs a fix for a symlink-manipulation bug in zic that was
introduced in 2016g. It probably isn't interesting for our use-case,
but I'm not quite sure, so let's update while we're at it.
This is mostly to absorb some corner-case fixes in zic for year-2037
timestamps. The other changes that have been made are unlikely to affect
our usage, but nonetheless we may as well take 'em.
DST law changes in Turkey. Historical corrections for America/Los_Angeles,
Europe/Kirov, Europe/Moscow, Europe/Samara, and Europe/Ulyanovsk.
Rename Asia/Rangoon to Asia/Yangon, with a backward compatibility link.
The IANA crew continue their campaign to replace invented time zone
abbrevations with numeric GMT offsets. This update changes numerous zones
in Antarctica and the former Soviet Union, for instance Antarctica/Casey
now reports "+08" not "AWST" in the pg_timezone_names view. I kept these
abbreviations in the tznames/ data files, however, so that we will still
accept them for input. (We may want to start trimming those files someday,
but today is not that day.)
An exception is that since IANA no longer claims that "AMT" is in use
in Armenia for GMT+4, I replaced it in the Default file with GMT-4,
corresponding to Amazon Time which is in use in South America. It may be
that that meaning is also invented and IANA will drop it in a future
update; but for now, it seems silly to give pride of place to a meaning
not traceable to IANA over one that is.
After further reflection about the mess cleaned up in commit 39b691f25,
I decided the main bit of test coverage that was still missing was to
check that the non-default abbreviation-set files we supply are usable.
Add that.
Back-patch to supported branches, just because it seems like a good
idea to keep this all in sync.
