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2018-05-18Hot-fix ecpg regression test for missing ecpg_config.h inclusion.Tom Lane
I don't think this is really the best long-term answer, and in particular it doesn't fix the pre-existing hazard in sqltypes.h. But for the moment let's just try to make the buildfarm green again. Discussion: https://postgr.es/m/151935568942.1461.14623890240535309745@wrigleys.postgresql.org
2018-05-18Add some test coverage for ecpg's "long long" support.Tom Lane
This will only actually exercise the "long long" code paths on platforms where "long" is 32 bits --- otherwise, the SQL bigint type maps to plain "long", and we will test that code path instead. But that's probably sufficient coverage, and anyway we weren't testing either code path before. Dang Minh Huong, tweaked a bit by me Discussion: https://postgr.es/m/151935568942.1461.14623890240535309745@wrigleys.postgresql.org
2018-05-18Recognize that MSVC can support strtoll() and strtoull().Tom Lane
This is needed for full support of "long long" variables in ecpg, but the previous patch for bug #15080 (commits 51057feaa et al) missed it. In MSVC versions where the functions don't exist under those names, we can nonetheless use _strtoi64() and _strtoui64(). Like the previous patch, back-patch all the way. Dang Minh Huong Discussion: https://postgr.es/m/151935568942.1461.14623890240535309745@wrigleys.postgresql.org
2018-05-18Fix error message on short read of pg_controlMagnus Hagander
Instead of saying "error: success", indicate that we got a working read but it was too short.
2018-05-16Fix misprocessing of equivalence classes involving record_eq().Tom Lane
canonicalize_ec_expression() is supposed to agree with coerce_type() as to whether a RelabelType should be inserted to make a subexpression be valid input for the operators of a given opclass. However, it did the wrong thing with named-composite-type inputs to record_eq(): it put in a RelabelType to RECORDOID, which the parser doesn't. In some cases this was harmless because all code paths involving a particular equivalence class did the same thing, but in other cases this would result in failing to recognize a composite-type expression as being a member of an equivalence class that it actually is a member of. The most obvious bad effect was to fail to recognize that an index on a composite column could provide the sort order needed for a mergejoin on that column, as reported by Teodor Sigaev. I think there might be other, subtler, cases that result in misoptimization. It also seems possible that an unwanted RelabelType would sometimes get into an emitted plan --- but because record_eq and friends don't examine the declared type of their input expressions, that would not create any visible problems. To fix, just treat RECORDOID as if it were a polymorphic type, which in some sense it is. We might want to consider formalizing that a bit more someday, but for the moment this seems to be the only place where an IsPolymorphicType() test ought to include RECORDOID as well. This has been broken for a long time, so back-patch to all supported branches. Discussion: https://postgr.es/m/a6b22369-e3bf-4d49-f59d-0c41d3551e81@sigaev.ru
2018-05-09Update time zone data files to tzdata release 2018e.Tom Lane
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
2018-05-08Improve inefficient regexes in vacuumdb TAP test.Tom Lane
The regexes used in 102_vacuumdb_stages.pl to check the postmaster log for expected output contained several places with ".*.*", which is underdetermined and can cause exponential runtime growth in Perl's regex matcher (since it's not bright enough not to waste time seeing whether different splits of the same substring would allow a match). We were fortunate that the amount of text in the postmaster log was generally not enough to make the runtime go to the moon; although commit 6271fceb8 had been on the hairy edge of an obvious problem, thanks to its increasing the default log verbosity to DEBUG1. Experimentation shows that anyone who tried to run this test case with an even higher log verbosity would have been in for serious pain. But even at default logging level, fixing this saves several hundred ms on my workstation, more on slower buildfarm members. Remove the extra ".*"s, restoring more-or-less-linear matching speed. Back-patch to 9.4 where the test case was added, mostly in case anyone tries to do related debugging in a back branch. Discussion: https://postgr.es/m/32459.1525657786@sss.pgh.pa.us
2018-05-07Stamp 9.5.13.REL9_5_13Tom Lane
2018-05-07Translation updatesPeter Eisentraut
Source-Git-URL: git://git.postgresql.org/git/pgtranslation/messages.git Source-Git-Hash: 8807686cb166e570052e709ab45103c4e8ca2e29
2018-05-06Clear severity 5 perlcritic warnings from vcregress.plAndrew Dunstan
My recent update for python3 support used some idioms that are unapproved. This fixes them. Backpatch to all live branches like the original.
2018-05-05Tweak tests to support Python 3.7Peter Eisentraut
Python 3.7 removes the trailing comma in the repr() of BaseException (see <https://bugs.python.org/issue30399>), leading to test output differences. Work around that by composing the equivalent test output in a more manual way.
2018-05-05Remove extra newlines after PQerrorMessage()Peter Eisentraut
2018-05-05Fix scenario where streaming standby gets stuck at a continuation record.Heikki Linnakangas
If a continuation record is split so that its first half has already been removed from the master, and is only present in pg_wal, and there is a recycled WAL segment in the standby server that looks like it would contain the second half, recovery would get stuck. The code in XLogPageRead() incorrectly started streaming at the beginning of the WAL record, even if we had already read the first page. Backpatch to 9.4. In principle, older versions have the same problem, but without replication slots, there was no straightforward mechanism to prevent the master from recycling old WAL that was still needed by standby. Without such a mechanism, I think it's reasonable to assume that there's enough slack in how many old segments are kept around to not run into this, or you have a WAL archive. Reported by Jonathon Nelson. Analysis and patch by Kyotaro HORIGUCHI, with some extra comments by me. Discussion: https://www.postgresql.org/message-id/CACJqAM3xVz0JY1XFDKPP%2BJoJAjoGx%3DGNuOAshEDWCext7BFvCQ%40mail.gmail.com
2018-05-04Provide for testing on python3 modules when under MSVCAndrew Dunstan
This should have been done some years ago as promised in commit c4dcdd0c2. However, better late than never. Along the way do a little housekeeping, including using a simpler test for the python version being tested, and removing a redundant subroutine parameter. These changes only apply back to release 9.5. Backpatch to all live releases.
2018-05-04Allow MSYS as well as MINGW in Msys unameAndrew Dunstan
Msys2's uname -s outputs a string beginning MSYS rather than MINGW as is output by Msys. Allow either in pg_upgrade's test.sh. Backpatch to all live branches.
2018-05-04Sync our copy of the timezone library with IANA release tzcode2018e.Tom Lane
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
2018-05-03Add HOLD_INTERRUPTS section into FinishPreparedTransaction.Teodor Sigaev
If an interrupt arrives in the middle of FinishPreparedTransaction and any callback decide to call CHECK_FOR_INTERRUPTS (e.g. RemoveTwoPhaseFile can write a warning with ereport, which checks for interrupts) then it's possible to leave current GXact undeleted. Backpatch to all supported branches Stas Kelvich Discussion: ihttps://www.postgresql.org/message-id/3AD85097-A3F3-4EBA-99BD-C38EDF8D2949@postgrespro.ru
2018-05-02Revert back-branch changes in power()'s behavior for NaN inputs.Tom Lane
Per discussion, the value of fixing these bugs in the back branches doesn't outweigh the downsides of changing corner-case behavior in a minor release. Hence, revert commits 217d8f3a1 and 4d864de48 in the v10 branch and the corresponding commits in 9.3-9.6. Discussion: https://postgr.es/m/75DB81BEEA95B445AE6D576A0A5C9E936A73E741@BPXM05GP.gisp.nec.co.jp
2018-05-01On all Windows platforms, not just Cygwin, use _timezone and _tzname.Tom Lane
Back-patch commit 868628e4f into the 9.5 branch, so that we can support building that branch with Visual Studio 2015. This patch itself could go further back, but other VS2015 patches such as 0fb54de9a and c8e81afc6 were only back-patched to 9.5, so there seems little point in handling this one differently. Discussion: https://postgr.es/m/CAD=LzWFg+Z-KUS3Wm8-1J2vOuYErJXbjuE6b7quzswQEBXJWMQ@mail.gmail.com
2018-04-29Fix bogus list-iteration code in pg_regress.c, affecting ecpg tests only.Tom Lane
While looking at a recent buildfarm failure in the ecpg tests, I wondered why the pg_regress output claimed the stderr part of the test failed, when the regression diffs were clearly for the stdout part. Looking into it, the reason is that pg_regress.c's logic for iterating over three parallel lists is wrong, and has been wrong since it was written: it advances the "tag" pointer at a different place in the loop than the other two pointers. Fix that.
2018-04-29Avoid wrong results for power() with NaN input on more platforms.Tom Lane
Buildfarm results show that the modern POSIX rule that 1 ^ NaN = 1 is not honored on *BSD until relatively recently, and really old platforms don't believe that NaN ^ 0 = 1 either. (This is unsurprising, perhaps, since SUSv2 doesn't require either behavior.) In hopes of getting to platform independent behavior, let's deal with all the NaN-input cases explicitly in dpow(). Note that numeric_power() doesn't know either of these special cases. But since that behavior is platform-independent, I think it should be addressed separately, and probably not back-patched. Discussion: https://postgr.es/m/75DB81BEEA95B445AE6D576A0A5C9E936A73E741@BPXM05GP.gisp.nec.co.jp
2018-04-29Update time zone data files to tzdata release 2018d.Tom Lane
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.
2018-04-29Avoid wrong results for power() with NaN input on some platforms.Tom Lane
Per spec, the result of power() should be NaN if either input is NaN. It appears that on some versions of Windows, the libc function does return NaN, but it also sets errno = EDOM, confusing our code that attempts to work around shortcomings of other platforms. Hence, add guard tests to avoid substituting a wrong result for the right one. It's been like this for a long time (and the odd behavior only appears in older MSVC releases, too) so back-patch to all supported branches. Dang Minh Huong, reviewed by David Rowley Discussion: https://postgr.es/m/75DB81BEEA95B445AE6D576A0A5C9E936A73E741@BPXM05GP.gisp.nec.co.jp
2018-04-25Correct pg_recvlogical server version test.Noah Misch
The predecessor test boiled down to "PQserverVersion(NULL) >= 100000", which is always false. No release includes that, so it could not have reintroduced CVE-2018-1058. Back-patch to 9.4, like the addition of the predecessor in commit 8d2814f274def85f39fbe997d454b01628cb5667. Discussion: https://postgr.es/m/20180422215551.GB2676194@rfd.leadboat.com
2018-04-20Fix race conditions when an event trigger is added concurrently with DDL.Tom Lane
EventTriggerTableRewrite crashed if there were table_rewrite triggers present, but there had not been when the calling command started. EventTriggerDDLCommandEnd called ddl_command_end triggers if present, even if there had been no such triggers when the calling command started, which would lead to a failure in pg_event_trigger_ddl_commands. In both cases, fix by doing nothing; it's better to wait till the next command when things will be properly initialized. In passing, remove an elog(DEBUG1) call that might have seemed interesting four years ago but surely isn't today. We found this because of intermittent failures in the buildfarm. Thanks to Alvaro Herrera and Andrew Gierth for analysis. Back-patch to 9.5; some of this code exists before that, but the specific hazards we need to guard against don't. Discussion: https://postgr.es/m/5767.1523995174@sss.pgh.pa.us
2018-04-20Change more places to be less trusting of RestrictInfo.is_pushed_down.Tom Lane
On further reflection, commit e5d83995e didn't go far enough: pretty much everywhere in the planner that examines a clause's is_pushed_down flag ought to be changed to use the more complicated behavior where we also check the clause's required_relids. Otherwise we could make incorrect decisions about whether, say, a clause is safe to use as a hash clause. Some (many?) of these places are safe as-is, either because they are never reached while considering a parameterized path, or because there are additional checks that would reject a pushed-down clause anyway. However, it seems smarter to just code them all the same way rather than rely on easily-broken reasoning of that sort. In support of that, invent a new macro RINFO_IS_PUSHED_DOWN that should be used in place of direct tests on the is_pushed_down flag. Like the previous patch, back-patch to all supported branches. Discussion: https://postgr.es/m/f8128b11-c5bf-3539-48cd-234178b2314d@proxel.se
2018-04-19Fix incorrect handling of join clauses pushed into parameterized paths.Tom Lane
In some cases a clause attached to an outer join can be pushed down into the outer join's RHS even though the clause is not degenerate --- this can happen if we choose to make a parameterized path for the RHS. If the clause ends up attached to a lower outer join, we'd misclassify it as being a "join filter" not a plain "filter" condition at that node, leading to wrong query results. To fix, teach extract_actual_join_clauses to examine each join clause's required_relids, not just its is_pushed_down flag. (The latter now seems vestigial, or at least in need of rethinking, but we won't do anything so invasive as redefining it in a bug-fix patch.) This has been wrong since we introduced parameterized paths in 9.2, though it's evidently hard to hit given the lack of previous reports. The test case used here involves a lateral function call, and I think that a lateral reference may be required to get the planner to select a broken plan; though I wouldn't swear to that. In any case, even if LATERAL is needed to trigger the bug, it still affects all supported branches, so back-patch to all. Per report from Andreas Karlsson. Thanks to Andrew Gierth for preliminary investigation. Discussion: https://postgr.es/m/f8128b11-c5bf-3539-48cd-234178b2314d@proxel.se
2018-04-19Enlarge find_other_exec's meager fgets bufferAlvaro Herrera
The buffer was 100 bytes long, which is barely sufficient when the version string gets longer (such as by configure --with-extra-version). Set it to MAXPGPATH. Author: Nikhil Sontakke Discussion: https://postgr.es/m/CAMGcDxfLfpYU_Jru++L6ARPCOyxr0W+2O3Q54TDi5XdYeU36ow@mail.gmail.com
2018-04-18Better fix for deadlock hazard in CREATE INDEX CONCURRENTLY.Tom Lane
Commit 54eff5311 did not account for the possibility that we'd have a transaction snapshot due to default_transaction_isolation being set high enough to require one. The transaction snapshot is enough to hold back our advertised xmin and thus risk deadlock anyway. The only way to get rid of that snap is to start a new transaction, so let's do that instead. Also throw in an assert checking that we really have gotten to a state where no xmin is being advertised. Back-patch to 9.4, like the previous commit. Discussion: https://postgr.es/m/CAMkU=1ztk3TpQdcUNbxq93pc80FrXUjpDWLGMeVBDx71GHNwZQ@mail.gmail.com
2018-04-16Fix broken collation-aware searches in SP-GiST text opclass.Tom Lane
spg_text_leaf_consistent() supposed that it should compare only Min(querylen, entrylen) bytes of the two strings, and then deal with any excess bytes in one string or the other by assuming the longer string is greater if the prefixes are equal. Quite aside from the fact that that's just wrong in some locales (e.g., 'ch' is not less than 'd' in cs_CZ), it also risked passing incomplete multibyte characters to strcoll(), with ensuing bad results. Instead, just pass the full strings to varstr_cmp, and let it decide what to do about unequal-length strings. Fortunately, this error doesn't imply any index corruption, it's just that searches might return the wrong set of entries. Per report from Emre Hasegeli, though this is not his patch. Thanks to Peter Geoghegan for review and discussion. This code was born broken, so back-patch to all supported branches. In HEAD, I failed to resist the temptation to do a bit of cosmetic cleanup/pgindent'ing on 710d90da1, too. Discussion: https://postgr.es/m/CAE2gYzzb6K51VnTq5i5p52z+j9p2duEa-K1T3RrC_GQEynAKEg@mail.gmail.com
2018-04-13In libpq, free any partial query result before collecting a server error.Tom Lane
We'd throw away the partial result anyway after parsing the error message. Throwing it away beforehand costs nothing and reduces the risk of out-of-memory failure. Also, at least in systems that behave like glibc/Linux, if the partial result was very large then the error PGresult would get allocated at high heap addresses, preventing the heap storage used by the partial result from being released to the OS until the error PGresult is freed. In psql >= 9.6, we hold onto the error PGresult until another error is received (for \errverbose), so that this behavior causes a seeming memory leak to persist for awhile, as in a recent complaint from Darafei Praliaskouski. This is a potential performance regression from older versions, justifying back-patching at least that far. But similar behavior may occur in other client applications, so it seems worth just back-patching to all supported branches. Discussion: https://postgr.es/m/CAC8Q8tJ=7cOkPePyAbJE_Pf691t8nDFhJp0KZxHvnq_uicfyVg@mail.gmail.com
2018-04-12Fix bogus affix-merging code.Tom Lane
NISortAffixes() compared successive compound affixes incorrectly, thus possibly failing to merge identical affixes, or (less likely) merging ones that shouldn't be merged. The user-visible effects of this are unclear, to me anyway. Per bug #15150 from Alexander Lakhin. It's been broken for a long time, so back-patch to all supported branches. Arthur Zakirov Discussion: https://postgr.es/m/152353327780.31225.13445405496721177988@wrigleys.postgresql.org
2018-04-11Ignore nextOid when replaying an ONLINE checkpoint.Tom Lane
The nextOid value is from the start of the checkpoint and may well be stale compared to values from more recent XLOG_NEXTOID records. Previously, we adopted it anyway, allowing the OID counter to go backwards during a crash. While this should be harmless, it contributed to the severity of the bug fixed in commit 0408e1ed5, by allowing duplicate TOAST OIDs to be assigned immediately following a crash. Without this error, that issue would only have arisen when TOAST objects just younger than a multiple of 2^32 OIDs were deleted and then not vacuumed in time to avoid a conflict. Pavan Deolasee Discussion: https://postgr.es/m/CABOikdOgWT2hHkYG3Wwo2cyZJq2zfs1FH0FgX-=h4OLosXHf9w@mail.gmail.com
2018-04-11Do not select new object OIDs that match recently-dead entries.Tom Lane
When selecting a new OID, we take care to avoid picking one that's already in use in the target table, so as not to create duplicates after the OID counter has wrapped around. However, up to now we used SnapshotDirty when scanning for pre-existing entries. That ignores committed-dead rows, so that we could select an OID matching a deleted-but-not-yet-vacuumed row. While that mostly worked, it has two problems: * If recently deleted, the dead row might still be visible to MVCC snapshots, creating a risk for duplicate OIDs when examining the catalogs within our own transaction. Such duplication couldn't be visible outside the object-creating transaction, though, and we've heard few if any field reports corresponding to such a symptom. * When selecting a TOAST OID, deleted toast rows definitely *are* visible to SnapshotToast, and will remain so until vacuumed away. This leads to a conflict that will manifest in errors like "unexpected chunk number 0 (expected 1) for toast value nnnnn". We've been seeing reports of such errors from the field for years, but the cause was unclear before. The fix is simple: just use SnapshotAny to search for conflicting rows. This results in a slightly longer window before object OIDs can be recycled, but that seems unlikely to create any large problems. Pavan Deolasee Discussion: https://postgr.es/m/CABOikdOgWT2hHkYG3Wwo2cyZJq2zfs1FH0FgX-=h4OLosXHf9w@mail.gmail.com
2018-04-11Make local copy of client hostnames in backend status array.Heikki Linnakangas
The other strings, application_name and query string, were snapshotted to local memory in pgstat_read_current_status(), but we forgot to do that for client hostnames. As a result, the client hostname would appear to change in the local copy, if the client disconnected. Backpatch to all supported versions. Author: Edmund Horner Reviewed-by: Michael Paquier Discussion: https://www.postgresql.org/message-id/CAMyN-kA7aOJzBmrYFdXcc7Z0NmW%2B5jBaf_m%3D_-77uRNyKC9r%3DA%40mail.gmail.com
2018-04-10Fix incorrect close() call in dsm_impl_mmap().Tom Lane
One improbable error-exit path in this function used close() where it should have used CloseTransientFile(). This is unlikely to be hit in the field, and I think the consequences wouldn't be awful (just an elog(LOG) bleat later). But a bug is a bug, so back-patch to 9.4 where this code came in. Pan Bian Discussion: https://postgr.es/m/152056616579.4966.583293218357089052@wrigleys.postgresql.org
2018-04-07Remove overzeleous assertions in pg_atomic_flag code.Andres Freund
The atomics code asserts proper alignment in various places. That's mainly because the alignment of 64bit integers is not sufficient for atomic operations on all platforms. Some ABIs only have four byte alignment, but don't have atomic behavior when crossing page boundaries. The flags code isn't affected by that however, as the type alignment always is sufficient for atomic operations. Nevertheless the code asserted alignment requirements. Before 8c3debbb it was only broken on hppa, after it probably affect further platforms. Thus remove the assertions for pg_atomic_flag operators. Per buildfarm animal pademelon. Discussion: https://postgr.es/m/7223.1523124425@sss.pgh.pa.us Backpatch: 9.5-
2018-04-06Fix and improve pg_atomic_flag fallback implementation.Andres Freund
The atomics fallback implementation for pg_atomic_flag was broken, returning the inverted value from pg_atomic_test_set_flag(). This was unnoticed because a) atomic flags were unused until recently b) the test code wasn't run when the fallback implementation was in use (because it didn't allow to test for some edge cases). Fix the bug, and improve the fallback so it has the same behaviour as the non-fallback implementation in the problematic edge cases. That breaks ABI compatibility in the back branches when fallbacks are in use, but given they were broken until now... Author: Andres Freund Reported-by: Daniel Gustafsson Discussion: https://postgr.es/m/FB948276-7B32-4B77-83E6-D00167F8EEB4@yesql.se https://postgr.es/m/20180406233854.uni2h3mbnveczl32@alap3.anarazel.de Backpatch: 9.5-, where the atomics abstraction was introduced.
2018-04-04Also fix the descriptions in pg_config.h.win32.Heikki Linnakangas
I missed pg_config.h.win32 in the previous commit that fixed these in pg_config.h.in.
2018-04-04Fix incorrect description of USE_SLICING_BY_8_CRC32C.Heikki Linnakangas
And a typo in the description of USE_SSE42_CRC32C_WITH_RUNTIME_CHECK, spotted by Daniel Gustafsson.
2018-03-31Fix assorted issues in parallel vacuumdb.Tom Lane
Avoid storing the result of PQsocket() in a pgsocket variable; it's declared as int, and the no-socket test is properly written as "x < 0" not "x == PGINVALID_SOCKET". This accidentally had no bad effect because we never got to init_slot() with a bad connection, but it's still wrong. Actually, it seems like we should avoid storing the result for a long period at all. The function's not so expensive that it's worth avoiding, and the existing coding technique here would fail if anyone tried to PQreset the connection during the life of the program. Hence, just re-call PQsocket every time we construct a select(2) mask. Speaking of select(), GetIdleSlot imagined that it could compute the select mask once and continue to use it over multiple calls to select_loop(), which is pretty bogus since that would stomp on the mask on return. This could only matter if the function's outer loop iterated more than once, which is unlikely (it'd take some connection receiving data, but not enough to complete its command). But if it did happen, we'd acquire "tunnel vision" and stop watching the other connections for query termination, with the effect of losing parallelism. Another way in which GetIdleSlot could lose parallelism is that once PQisBusy returns false, it would lock in on that connection and do PQgetResult until that returns NULL; in some cases that could result in blocking. (Perhaps this can never happen in vacuumdb due to the limited set of commands that it can issue, but I'm not quite sure of that, and even if true today it's not a future-proof assumption.) Refactor the code to do that properly, so that it risks blocking in PQgetResult only in cases where we need to wait anyway. Another loss-of-parallelism problem, which *is* easily demonstrable, is that any setup queries issued during prepare_vacuum_command() were always issued on the last-to-be-created connection, whether or not that was idle. Long-running operations on that connection thus prevented issuance of additional operations on the other ones, except in the limited cases where no preparatory query was needed. Instead, wait till we've identified a free connection and use that one. Also, avoid core dump due to undersized malloc request in the case that no tables are identified to be vacuumed. The bogus no-socket test was noted by CharSyam, the other problems identified in my own code review. Back-patch to 9.5 where parallel vacuumdb was introduced. Discussion: https://postgr.es/m/CAMrLSE6etb33-192DTEUGkV-TsvEcxtBDxGWG1tgNOMnQHwgDA@mail.gmail.com
2018-03-30Fix bogus provolatile/proparallel markings on a few built-in functions.Tom Lane
Richard Yen reported that pg_upgrade failed if the target cluster had force_parallel_mode = on, because binary_upgrade_create_empty_extension() is marked parallel restricted, allowing it to be executed in parallel mode, which complains because it tries to acquire an XID. In general, no function that might try to modify database data should be considered parallel safe or restricted, since execution of it might force XID acquisition. We found several other examples of this mistake. Furthermore, functions that execute user-supplied SQL queries or query fragments, or pull data from user-supplied cursors, had better be marked both volatile and parallel unsafe, because we don't know what the supplied query or cursor might try to do. There were several tsquery and XML functions that had the wrong proparallel marking for this, and some of them were even mislabeled as to volatility. All these bugs are old, dating back to 9.6 for the proparallel mistakes and much further for the provolatile mistakes. We can't force a catversion bump in the back branches, but we can at least ensure that installations initdb'd in future have the right values. Thomas Munro and Tom Lane Discussion: https://postgr.es/m/CAEepm=2sNDScSLTfyMYu32Q=ob98ZGW-vM_2oLxinzSABGQ6VA@mail.gmail.com
2018-03-29Fix handling of files that source server removes during pg_rewind is running.Fujii Masao
After processing the filemap to build the list of chunks that will be fetched from the source to rewing the target server, it is possible that a file which was previously processed is removed from the source. A simple example of such an occurence is a WAL segment which gets recycled on the target in-between. When the filemap is processed, files not categorized as relation files are first truncated to prepare for its full copy of which is going to be taken from the source, divided into a set of junks. However, for a recycled WAL segment, this would result in a segment which has a zero-byte size. With such an empty file, post-rewind recovery thinks that records are saved but they are actually not because of the truncation which happened when processing the filemap, resulting in data loss. In order to fix the problem, make sure that files which are found as removed on the source when receiving chunks of them are as well deleted on the target server for consistency. Back-patch to 9.5 where pg_rewind was added. Author: Tsunakawa Takayuki Reviewed-by: Michael Paquier Reported-by: Tsunakawa Takayuki Discussion: https://postgr.es/m/0A3221C70F24FB45833433255569204D1F8DAAA2%40G01JPEXMBYT05
2018-03-28Fix actual and potential double-frees around tuplesort usage.Tom Lane
tuplesort_gettupleslot() passed back tuples allocated in the tuplesort's own memory context, even when the caller was responsible to free them. This created a double-free hazard, because some callers might destroy the tuplesort object (via tuplesort_end) before trying to clean up the last returned tuple. To avoid this, change the API to specify that the tuple is allocated in the caller's memory context. v10 and HEAD already did things that way, but in 9.5 and 9.6 this is a live bug that can demonstrably cause crashes with some grouping-set usages. In 9.5 and 9.6, this requires doing an extra tuple copy in some cases, which is unfortunate. But the amount of refactoring needed to avoid it seems excessive for a back-patched change, especially since the cases where an extra copy happens are less performance-critical. Likewise change tuplesort_getdatum() to return pass-by-reference Datums in the caller's context not the tuplesort's context. There seem to be no live bugs among its callers, but clearly the same sort of situation could happen in future. For other tuplesort fetch routines, continue to allocate the memory in the tuplesort's context. This is a little inconsistent with what we now do for tuplesort_gettupleslot() and tuplesort_getdatum(), but that's preferable to adding new copy overhead in the back branches where it's clearly unnecessary. These other fetch routines provide the weakest possible guarantees about tuple memory lifespan from v10 on, anyway, so this actually seems more consistent overall. Adjust relevant comments to reflect these API redefinitions. Arguably, we should change the pre-9.5 branches as well, but since there are no known failure cases there, it seems not worth the risk. Peter Geoghegan, per report from Bernd Helmle. Reviewed by Kyotaro Horiguchi; thanks also to Andreas Seltenreich for extracting a self-contained test case. Discussion: https://postgr.es/m/1512661638.9720.34.camel@oopsware.de
2018-03-26Fix thinko in commentAlvaro Herrera
The listed numbers disagreed with the ones being used in the symbols; but instead of just fixing the numbers in the comment, use the symbolic name instead, which seems clearer. This has been wrong all along, so apply back to 9.5 where BRIN was introduced. Reported-by: Tomas Vondra Discussion: https://postgr.es/m/5ff514f2-8b1e-6366-b11c-8e2ed442562d@2ndquadrant.com
2018-03-23Fix make rules that generate multiple output files.Tom Lane
For years, our makefiles have correctly observed that "there is no correct way to write a rule that generates two files". However, what we did is to provide empty rules that "generate" the secondary output files from the primary one, and that's not right either. Depending on the details of the creating process, the primary file might end up timestamped later than one or more secondary files, causing subsequent make runs to consider the secondary file(s) out of date. That's harmless in a plain build, since make will just re-execute the empty rule and nothing happens. But it's fatal in a VPATH build, since make will expect the secondary file to be rebuilt in the build directory. This would manifest as "file not found" failures during VPATH builds from tarballs, if we were ever unlucky enough to ship a tarball with apparently out-of-date secondary files. (It's not clear whether that has ever actually happened, but it definitely could.) To ensure that secondary output files have timestamps >= their primary's, change our makefile convention to be that we provide a "touch $@" action not an empty rule. Also, make sure that this rule actually gets invoked during a distprep run, else the hazard remains. It's been like this a long time, so back-patch to all supported branches. In HEAD, I skipped the changes in src/backend/catalog/Makefile, because those rules are due to get replaced soon in the bootstrap data format patch, and there seems no need to create a merge issue for that patch. If for some reason we fail to land that patch in v11, we'll need to back-fill the changes in that one makefile from v10. Discussion: https://postgr.es/m/18556.1521668179@sss.pgh.pa.us
2018-03-22Fix tuple counting in SP-GiST index build.Tom Lane
Count the number of tuples in the index honestly, instead of assuming that it's the same as the number of tuples in the heap. (It might be different if the index is partial.) Back-patch to all supported versions. Tomas Vondra Discussion: https://postgr.es/m/3b3d8eac-c709-0d25-088e-b98339a1b28a@2ndquadrant.com
2018-03-21Fix mishandling of quoted-list GUC values in pg_dump and ruleutils.c.Tom Lane
Code that prints out the contents of setconfig or proconfig arrays in SQL format needs to handle GUC_LIST_QUOTE variables differently from other ones, because for those variables, flatten_set_variable_args() already applied a layer of quoting. The value can therefore safely be printed as-is, and indeed must be, or flatten_set_variable_args() will muck it up completely on reload. For all other GUC variables, it's necessary and sufficient to quote the value as a SQL literal. We'd recognized the need for this long ago, but mis-analyzed the need slightly, thinking that all GUC_LIST_INPUT variables needed the special treatment. That's actually wrong, since a valid value of a LIST variable might include characters that need quoting, although no existing variables accept such values. More to the point, we hadn't made any particular effort to keep the various places that deal with this up-to-date with the set of variables that actually need special treatment, meaning that we'd do the wrong thing with, for example, temp_tablespaces values. This affects dumping of SET clauses attached to functions, as well as ALTER DATABASE/ROLE SET commands. In ruleutils.c we can fix it reasonably honestly by exporting a guc.c function that allows discovering the flags for a given GUC variable. But pg_dump doesn't have easy access to that, so continue the old method of having a hard-wired list of affected variable names. At least we can fix it to have just one list not two, and update the list to match current reality. A remaining problem with this is that it only works for built-in GUC variables. pg_dump's list obvious knows nothing of third-party extensions, and even the "ask guc.c" method isn't bulletproof since the relevant extension might not be loaded. There's no obvious solution to that, so for now, we'll just have to discourage extension authors from inventing custom GUCs that need GUC_LIST_QUOTE. This has been busted for a long time, so back-patch to all supported branches. Michael Paquier and Tom Lane, reviewed by Kyotaro Horiguchi and Pavel Stehule Discussion: https://postgr.es/m/20180111064900.GA51030@paquier.xyz
2018-03-19Fix some corner-case issues in REFRESH MATERIALIZED VIEW CONCURRENTLY.Tom Lane
refresh_by_match_merge() has some issues in the way it builds a SQL query to construct the "diff" table: 1. It doesn't require the selected unique index(es) to be indimmediate. 2. It doesn't pay attention to the particular equality semantics enforced by a given index, but just assumes that they must be those of the column datatype's default btree opclass. 3. It doesn't check that the indexes are btrees. 4. It's insufficiently careful to ensure that the parser will pick the intended operator when parsing the query. (This would have been a security bug before CVE-2018-1058.) 5. It's not careful about indexes on system columns. The way to fix #4 is to make use of the existing code in ri_triggers.c for generating an arbitrary binary operator clause. I chose to move that to ruleutils.c, since that seems a more reasonable place to be exporting such functionality from than ri_triggers.c. While #1, #3, and #5 are just latent given existing feature restrictions, and #2 doesn't arise in the core system for lack of alternate opclasses with different equality behaviors, #4 seems like an issue worth back-patching. That's the bulk of the change anyway, so just back-patch the whole thing to 9.4 where this code was introduced. Discussion: https://postgr.es/m/13836.1521413227@sss.pgh.pa.us
2018-03-19Fix performance hazard in REFRESH MATERIALIZED VIEW CONCURRENTLY.Tom Lane
Jeff Janes discovered that commit 7ca25b7de made one of the queries run by REFRESH MATERIALIZED VIEW CONCURRENTLY perform badly. The root cause is bad cardinality estimation for correlated quals, but a principled solution to that problem is some way off, especially since the planner lacks any statistics about whole-row variables. Moreover, in non-error cases this query produces no rows, meaning it must be run to completion; but use of LIMIT 1 encourages the planner to pick a fast-start, slow-completion plan, exactly not what we want. Remove the LIMIT clause, and instead rely on the count parameter we pass to SPI_execute() to prevent excess work if the query does return some rows. While we've heard no field reports of planner misbehavior with this query, it could be that people are having performance issues that haven't reached the level of pain needed to cause a bug report. In any case, that LIMIT clause can't possibly do anything helpful with any existing version of the planner, and it demonstrably can cause bad choices in some cases, so back-patch to 9.4 where the code was introduced. Thomas Munro Discussion: https://postgr.es/m/CAMkU=1z-JoGymHneGHar1cru4F1XDfHqJDzxP_CtK5cL3DOfmg@mail.gmail.com