To prevent possibly breaking indexes on enum columns, we must keep
uncommitted enum values from getting stored in tables, unless we
can be sure that any such column is new in the current transaction.
Formerly, we enforced this by disallowing ALTER TYPE ... ADD VALUE
from being executed at all in a transaction block, unless the target
enum type had been created in the current transaction. This patch
removes that restriction, and instead insists that an uncommitted enum
value can't be referenced unless it belongs to an enum type created
in the same transaction as the value. Per discussion, this should be
a bit less onerous. It does require each function that could possibly
return a new enum value to SQL operations to check this restriction,
but there aren't so many of those that this seems unmaintainable.
Andrew Dunstan and Tom Lane
Discussion: <4075.1459088427@sss.pgh.pa.us>
When pg_logical_slot_get_changes(...) sets confirmed_flush_lsn to the point at
which replay stopped, it doesn't dirty the replication slot. So if the replay
didn't cause restart_lsn or catalog_xmin to change as well, this change will
not get written out to disk. Even on a clean shutdown.
If Pg crashes or restarts, a subsequent pg_logical_slot_get_changes(...) call
will see the same changes already replayed since it uses the slot's
confirmed_flush_lsn as the start point for fetching changes. The caller can't
specify a start LSN when using the SQL interface.
Mark the slot as dirty after reading changes using the SQL interface so that
users won't see repeated changes after a clean shutdown. Repeated changes still
occur when using the walsender interface or after an unclean shutdown.
Craig Ringer
Andres is apparently the only hacker who thinks this code is better as-is.
I (tgl) follow some of his logic, but the fact that it's setting off
warnings from static code analyzers seems like a sufficient reason to
put the complexity into a comment rather than the code.
Aleksander Alekseev
Discussion: <20160404190345.54d84ee8@fujitsu>
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.
Commit b2cbced9e instituted a policy of referring to the timezone database
as the "IANA timezone database" in our user-facing documentation.
Propagate that wording into a couple of places that were still using "zic"
to refer to the database, which is definitely not right (zic is the
compilation tool, not the data).
Back-patch, not because this is very important in itself, but because
we routinely cherry-pick updates to the tznames files and I don't want
to risk future merge failures.
split_to_stringlist() doesn't modify its first argument nor expect it
to remain valid after exit, so there's no need to duplicate the optarg
string at the call sites. Per Coverity. (This has been wrong all along,
but commit 052cc223d changed the useless calls from "strdup" to
"pg_strdup", which apparently made Coverity think it's a new bug.
It's not, but it's also not worth back-patching.)
Coverity complained about the for(;;) loop, because it never actually
iterated. It was used just to be able to use "break" to exit it early. I
agree with Coverity, that's a bit confusing, so refactor the code to
use if-else instead.
While we're at it, use a local variable to hold the "current" node. That's
shorter and clearer than referring to "iter->last_visited" all the time.
In addition to the existing decimal-milliseconds output value,
display the same value in mm:ss.fff format if it exceeds one second.
Tack on hours and even days fields if the interval is large enough.
This avoids needing mental arithmetic to convert the values into
customary time units.
Corey Huinker, reviewed by Gerdan Santos; bikeshedding by many
Discussion: <CADkLM=dbC4R8sbbuFXQVBFWoJGQkTEW8RWnC0PbW9nZsovZpJQ@mail.gmail.com>
These were evidently introduced by yesterday's commit 9cca11c91,
which perhaps needs more review than it got.
Per report from Andreas Seltenreich and additional examination
of nearby code.
Report: <87oa45qfwq.fsf@credativ.de>
computeLeafRecompressWALData() tried to produce a uint16 WAL log field by
memcpy'ing the first two bytes of an int-sized variable. That accidentally
works on little-endian hardware, but not at all on big-endian. Replay then
thinks it's looking at an ADDITEMS action with zero entries, and reads the
first two bytes of the first TID therein as the next segno/action,
typically leading to "unexpected GIN leaf action" errors during replay.
Even if replay failed to crash, the resulting GIN index page would surely
be incorrect. To fix, just declare the variable as uint16 instead.
Per bug #14295 from Spencer Thomason (much thanks to Spencer for turning
his problem into a self-contained test case). This likely also explains
a previous report of the same symptom from Bernd Helmle.
Back-patch to 9.4 where the problem was introduced (by commit 14d02f0bb).
Discussion: <20160826072658.15676.7628@wrigleys.postgresql.org>
Possible-Report: <2DA7350F7296B2A142272901@eje.land.credativ.lan>
Previously, we threw an error if a dynamic timezone abbreviation did not
match any abbreviation recorded in the referenced IANA time zone entry.
That seemed like a good consistency check at the time, but it turns out
that a number of the abbreviations in the IANA database are things that
Olson and crew made up out of whole cloth. Their current policy is to
remove such names in favor of using simple numeric offsets. Perhaps
unsurprisingly, a lot of these made-up abbreviations have varied in meaning
over time, which meant that our commit b2cbced9e and later changes made
them into dynamic abbreviations. So with newer IANA database versions
that don't mention these abbreviations at all, we fail, as reported in bug
#14307 from Neil Anderson. It's worse than just a few unused-in-the-wild
abbreviations not working, because the pg_timezone_abbrevs view stops
working altogether (since its underlying function tries to compute the
whole view result in one call).
We considered deleting these abbreviations from our abbreviations list, but
the problem with that is that we can't stay ahead of possible future IANA
changes. Instead, let's leave the abbreviations list alone, and treat any
"orphaned" dynamic abbreviation as just meaning the referenced time zone.
It will behave a bit differently than it used to, in that you can't any
longer override the zone's standard vs. daylight rule by using the "wrong"
abbreviation of a pair, but that's better than failing entirely. (Also,
this solution can be interpreted as adding a small new feature, which is
that any abbreviation a user wants can be defined as referencing a time
zone name.)
Back-patch to all supported branches, since this problem affects all
of them when using tzdata 2016f or newer.
Report: <20160902031551.15674.67337@wrigleys.postgresql.org>
Discussion: <6189.1472820913@sss.pgh.pa.us>
When building libpq, ip.c and md5.c were symlinked or copied from
src/backend/libpq into src/interfaces/libpq, but now that we have a
directory specifically for routines that are shared between the server and
client binaries, src/common/, move them there.
Some routines in ip.c were only used in the backend. Keep those in
src/backend/libpq, but rename to ifaddr.c to avoid confusion with the file
that's now in common.
Fix the comment in src/common/Makefile to reflect how libpq actually links
those files.
There are two more files that libpq symlinks directly from src/backend:
encnames.c and wchar.c. I don't feel compelled to move those right now,
though.
Patch by Michael Paquier, with some changes by me.
Discussion: <69938195-9c76-8523-0af8-eb718ea5b36e@iki.fi>
This introduces a numeric sum accumulator, which performs better than
repeatedly calling add_var(). The performance comes from using wider digits
and delaying carry propagation, tallying positive and negative values
separately, and avoiding a round of palloc/pfree on every value. This
speeds up SUM(), as well as other standard aggregates like AVG() and
STDDEV() that also calculate a sum internally.
Reviewed-by: Andrey Borodin
Discussion: <c0545351-a467-5b76-6d46-4840d1ea8aa4@iki.fi>
While we don't need multiple iterators at the moment, the interface is
nicer and less dangerous this way.
Aleksander Alekseev, with some changes by me.
A majority of callers seem to have believed that this was the API spec
already, because they omitted any check for a NULL result, and hence
would crash on an out-of-shared-memory failure. The original proposal
was to just add such error checks everywhere, but that does nothing to
prevent similar omissions in future. Instead, let's make ShmemAlloc()
throw the error (so we can remove the caller-side checks that do exist),
and introduce a new function ShmemAllocNoError() that has the previous
behavior of returning NULL, for the small number of callers that need
that and are prepared to do the right thing. This also lets us remove
the rather wishy-washy behavior of printing a WARNING for out-of-shmem,
which never made much sense: either the caller has a strategy for
dealing with that, or it doesn't. It's not ShmemAlloc's business to
decide whether a warning is appropriate.
The v10 release notes will need to call this out as a significant
source-code change. It's likely that it will be a bug fix for
extension callers too, but if not, they'll need to change to using
ShmemAllocNoError().
This is nominally a bug fix, but the odds that it's fixing any live
bug are actually rather small, because in general the requests
being made by the unchecked callers were already accounted for in
determining the overall shmem size, so really they ought not fail.
Between that and the possible impact on extensions, no back-patch.
Discussion: <24843.1472563085@sss.pgh.pa.us>
Unlike PL/Tcl, PL/Perl at least made an attempt to clean up after itself
when a function gets redefined. But it was still using TopMemoryContext
for the fn_mcxt of argument/result I/O functions, resulting in the
potential for memory leaks depending on what those functions did, and the
retail alloc/free logic was pretty bulky as well. Fix things to use a
per-function memory context like the other PLs now do. Tweak a couple of
places where things were being done in a not-very-safe order (on the
principle that a memory leak is better than leaving global state
inconsistent after an error). Also make some minor cosmetic adjustments,
mostly in field names, to make the code look similar to the way PL/Tcl does
now wherever it's essentially the same logic.
Michael Paquier and Tom Lane
Discussion: <CAB7nPqSOyAsHC6jL24J1B+oK3p=yyNoFU0Vs_B6fd2kdd5g5WQ@mail.gmail.com>
Formerly, the memory used to represent a PL/Tcl function was allocated with
malloc() or in TopMemoryContext, and we'd leak it all if the function got
redefined during the session. Instead, create a per-function context and
keep everything in or under that context. Add a reference-counting
mechanism (like the one plpgsql has long had) so that we can safely clean
up an old function definition, either immediately if it's not being
executed or at the end of the outermost execution.
Currently, we only detect that a cached function is obsolete when we next
attempt to call that function. So this covers the updated-definition case
but leaves cruft around after DROP FUNCTION. It's not clear whether it's
worth installing a syscache invalidation callback to watch for drops;
none of the other PLs do, so for now we won't do it here either.
Michael Paquier and Tom Lane
Discussion: <CAB7nPqSOyAsHC6jL24J1B+oK3p=yyNoFU0Vs_B6fd2kdd5g5WQ@mail.gmail.com>
The hack embodied in commit 4ba61a487 no longer works after today's change
to allow DatumGetFloat4/Float4GetDatum to be inlined (commit 14cca1bf8).
Probably what's happening is that the faulty compilers are deciding that
the now-inlined assignment is a no-op and so they're not required to
round to float4 width.
We had a bunch of similar issues earlier this year in the degree-based
trig functions, and eventually settled on using volatile intermediate
variables as the least ugly method of forcing recalcitrant compilers
to do what the C standard says (cf commit 82311bcdd). Let's see if
that method works here.
Discussion: <4640.1472664476@sss.pgh.pa.us>
Since we removed SSL renegotiation, there's no longer any reason to
keep track of the amount of data transferred over the link.
Daniel Gustafsson
Discussion: <FEA7F89C-ECDF-4799-B789-2F8DDCBA467F@yesql.se>
Now that we are OK with using static inline functions, we can use them
to avoid function call overhead of pass-by-val versions of Float4GetDatum,
DatumGetFloat8, and Float8GetDatum. Those functions are only a few CPU
instructions long, but they could not be written into macros previously,
because we need a local union variable for the conversion.
I kept the pass-by-ref versions as regular functions. They are very simple
too, but they call palloc() anyway, so shaving a few instructions from the
function call doesn't seem so important there.
Discussion: <dbb82a4a-2c15-ba27-dd0a-009d2aa72b77@iki.fi>
This can't really work because standby_mode expects there to be more
WAL arriving, which there will not ever be because there's no WAL
receiver process to fetch it. Moreover, if standby_mode is on then
hot standby might also be turned on, causing even more strangeness
because that expects read-only sessions to be executing in parallel.
Bernd Helmle reported a case where btree_xlog_delete_get_latestRemovedXid
got confused, but rather than band-aiding individual problems it seems
best to prevent getting anywhere near this state in the first place.
Back-patch to all supported branches.
In passing, also fix some omissions of errcodes in other ereport's in
readRecoveryCommandFile().
Michael Paquier (errcode hacking by me)
Discussion: <00F0B2CEF6D0CEF8A90119D4@eje.credativ.lan>
Where possible, use palloc or pg_malloc instead; otherwise, insert
explicit NULL checks.
Generally speaking, these are places where an actual OOM is quite
unlikely, either because they're in client programs that don't
allocate all that much, or they're very early in process startup
so that we'd likely have had a fork() failure instead. Hence,
no back-patch, even though this is nominally a bug fix.
Michael Paquier, with some adjustments by me
Discussion: <CAB7nPqRu07Ot6iht9i9KRfYLpDaF2ZuUv5y_+72uP23ZAGysRg@mail.gmail.com>
The previous API for this function had it returning a malloc'd string.
That meant that callers had to check for NULL return, which few of them
were doing, and it also meant that callers had to remember to free()
the string later, which required extra logic in most cases.
Instead, make simple_prompt() write into a buffer supplied by the caller.
Anywhere that the maximum required input length is reasonably small,
which is almost all of the callers, we can just use a local or static
array as the buffer instead of dealing with malloc/free.
A fair number of callers used "pointer == NULL" as a proxy for "haven't
requested the password yet". Maintaining the same behavior requires
adding a separate boolean flag for that, which adds back some of the
complexity we save by removing free()s. Nonetheless, this nets out
at a small reduction in overall code size, and considerably less code
than we would have had if we'd added the missing NULL-return checks
everywhere they were needed.
In passing, clean up the API comment for simple_prompt() and get rid
of a very-unnecessary malloc/free in its Windows code path.
This is nominally a bug fix, but it does not seem worth back-patching,
because the actual risk of an OOM failure in any of these places seems
pretty tiny, and all of them are client-side not server-side anyway.
This patch is by me, but it owes a great deal to Michael Paquier
who identified the problem and drafted a patch for fixing it the
other way.
Discussion: <CAB7nPqRu07Ot6iht9i9KRfYLpDaF2ZuUv5y_+72uP23ZAGysRg@mail.gmail.com>
While testing simple_prompt() revisions, I happened to notice that
current initdb behaves rather badly when --pwprompt is specified and
the user miskeys the second password. It complains about the mismatch,
does "rm -rf" on the data directory, and exits. The problem is that
since commit c4a8812cf, there's a standalone backend sitting waiting
for commands at that point. It gets unhappy about its datadir having
gone away, and spews a PANIC message at the user, which is not nice.
(And the shell then adds to the mess with meaningless bleating about a
core dump...) We don't really want that sort of thing to happen unless
there's an internal failure in initdb, which this surely is not.
The best fix seems to be to move the collection of the password
earlier, so that it's done essentially as part of argument collection,
rather than at the rather ad-hoc time it was done before.
Back-patch to 9.6 where the problem was introduced.
Since the hash AM is going to be revamped to have WAL, this is a good
opportunity to clean up the include file a little bit to avoid including
a lot of extra stuff in the future.
Author: Amit Kapila
OpenSSL officially only supports 1.0.1 and newer. Some OS distributions
still provide patches for 0.9.8, but anything older than that is not
interesting anymore. Let's simplify things by removing compatibility code.
Andreas Karlsson, with small changes by me.
The previous behavior was to silently change them to something valid.
That obscured the bugs fixed in commit ea268cdc9, and generally seems
less useful than complaining. Unlike the previous commit, though,
we'll do this in HEAD only --- it's a bit too late to be possibly
breaking third-party code in 9.6.
Discussion: <CA+TgmobNcELVd3QmLD3tx=w7+CokRQiC4_U0txjz=WHpfdkU=w@mail.gmail.com>
Previously pg_xlogdump failed to dump the contents of the WAL file
if the file starts with the continuation WAL record which spans
more than one pages. Since pg_xlogdump assumed that the continuation
record always fits on a page, it could not find the valid WAL record to
start reading from in that case.
This patch changes pg_xlogdump so that it can handle a continuation
WAL record which crosses a page boundary and find the valid record
to start reading from.
Back-patch to 9.3 where pg_xlogdump was introduced.
Author: Pavan Deolasee
Reviewed-By: Michael Paquier and Craig Ringer
Discussion: CABOikdPsPByMiG6J01DKq6om2+BNkxHTPkOyqHM2a4oYwGKsqQ@mail.gmail.com
I found that half a dozen (nearly 5%) of our AllocSetContextCreate calls
had typos in the context-sizing parameters. While none of these led to
especially significant problems, they did create minor inefficiencies,
and it's now clear that expecting people to copy-and-paste those calls
accurately is not a great idea. Let's reduce the risk of future errors
by introducing single macros that encapsulate the common use-cases.
Three such macros are enough to cover all but two special-purpose contexts;
those two calls can be left as-is, I think.
While this patch doesn't in itself improve matters for third-party
extensions, it doesn't break anything for them either, and they can
gradually adopt the simplified notation over time.
In passing, change TopMemoryContext to use the default allocation
parameters. Formerly it could only be extended 8K at a time. That was
probably reasonable when this code was written; but nowadays we create
many more contexts than we did then, so that it's not unusual to have a
couple hundred K in TopMemoryContext, even without considering various
dubious code that sticks other things there. There seems no good reason
not to let it use growing blocks like most other contexts.
Back-patch to 9.6, mostly because that's still close enough to HEAD that
it's easy to do so, and keeping the branches in sync can be expected to
avoid some future back-patching pain. The bugs fixed by these changes
don't seem to be significant enough to justify fixing them further back.
Discussion: <21072.1472321324@sss.pgh.pa.us>
This has been requested a few times, but the use-case for it was never
entirely clear. The reason for adding it now is that transmission of
error reports from parallel workers fails when NLS is active, because
pq_parse_errornotice() wrongly assumes that the existing severity field
is nonlocalized. There are other ways we could have fixed that, but the
other options were basically kluges, whereas this way provides something
that's at least arguably a useful feature along with the bug fix.
Per report from Jakob Egger. Back-patch into 9.6, because otherwise
parallel query is essentially unusable in non-English locales. The
problem exists in 9.5 as well, but we don't want to risk changing
on-the-wire behavior in 9.5 (even though the possibility of new error
fields is specifically called out in the protocol document). It may
be sufficient to leave the issue unfixed in 9.5, given the very limited
usefulness of pq_parse_errornotice in that version.
Discussion: <A88E0006-13CB-49C6-95CC-1A77D717213C@eggerapps.at>
HandleParallelMessages leaked memory into the caller's context. Since it's
called from ProcessInterrupts, there is basically zero certainty as to what
CurrentMemoryContext is, which means we could be leaking into long-lived
contexts. Over the processing of many worker messages that would grow to
be a problem. Things could be even worse than just a leak, if we happened
to service the interrupt while ErrorContext is current: elog.c thinks it
can reset that on its own whim, possibly yanking storage out from under
HandleParallelMessages.
Give HandleParallelMessages its own dedicated context instead, which we can
reset during each call to ensure there's no accumulation of wasted memory.
Discussion: <16610.1472222135@sss.pgh.pa.us>
The guiding principle for the last few patches in this area apparently
involved throwing darts.
Cosmetic only, but back-patch to 9.6 because there is no reason for
9.6 and HEAD to diverge yet in this file.
Copy the palloc'd strings into the correct context, ie ErrorContext
not wherever the source ErrorData is. This would be a large bug,
except that it appears that all catchers of thrown errors do either
EmitErrorReport or CopyErrorData before doing anything that would
cause transient memory contexts to be cleaned up. Still, it's wrong
and it will bite somebody someday.
Fix failure to copy cursorpos and internalpos.
Utter the appropriate incantations involving recursion_depth, so that
we'll behave sanely if we get an error inside pstrdup. (In general,
the body of this function ought to act like, eg, errdetail().)
Per code reading induced by Jakob Egger's report.
The previous coding here was capable of adding a "parallel worker" context
line to errors that were not, in fact, returned from a parallel worker.
Instead of using an errcontext callback to add that annotation, just paste
it onto the message by hand; this looks uglier but is more reliable.
Discussion: <19757.1472151987@sss.pgh.pa.us>
You can use ALTER FOREIGN TABLE SET WITH OIDS on a foreign table, but the
oid column read out as zeros, because the postgres_fdw didn't know about
it. Teach postgres_fdw how to fetch it.
Etsuro Fujita, with an additional test case by me.
Discussion: <56E90A76.5000503@lab.ntt.co.jp>
Commit f0c7b789a added a test case in case.sql that creates and then drops
both an '=' operator and the type it's for. Given the right timing, that
can cause a "cache lookup failed for type" failure in concurrent sessions,
which see the '=' operator as a potential match for '=' in a query, but
then the type is gone by the time they inquire into its properties.
It might be nice to make that behavior more robust someday, but as a
back-patchable solution, adjust the new test case so that the operator
is never visible to other sessions. Like the previous commit, back-patch
to all supported branches.
Discussion: <5983.1471371667@sss.pgh.pa.us>
When there is an identifiable REPLICA IDENTITY index on the target table,
heap_update leaks the id_attrs bitmapset. That's not many bytes, but it
adds up over enough rows, since the code typically runs in a query-lifespan
context. Bug introduced in commit e55704d8b, which did a rather poor job
of cloning the existing use-pattern for RelationGetIndexAttrBitmap().
Per bug #14293 from Zhou Digoal. Back-patch to 9.4 where the bug was
introduced.
Report: <20160824114320.15676.45171@wrigleys.postgresql.org>
Tom Lane
Simon Riggs
Heikki Linnakangas
Kevin Grittner
Robert Haas
Alvaro Herrera
Fujii Masao
Bruce Momjian