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2021-01-05Add an explicit cast to double when using fabs().Dean Rasheed
Commit bc43b7c2c0 used fabs() directly on an int variable, which apparently requires an explicit cast on some platforms. Per buildfarm.
2021-01-05Fix numeric_power() when the exponent is INT_MIN.Dean Rasheed
In power_var_int(), the computation of the number of significant digits to use in the computation used log(Abs(exp)), which isn't safe because Abs(exp) returns INT_MIN when exp is INT_MIN. Use fabs() instead of Abs(), so that the exponent is cast to a double before the absolute value is taken. Back-patch to 9.6, where this was introduced (by 7d9a4737c2). Discussion: https://postgr.es/m/CAEZATCVd6pMkz=BrZEgBKyqqJrt2xghr=fNc8+Z=5xC6cgWrWA@mail.gmail.com
2021-01-04Fix integer-overflow corner cases in substring() functions.Tom Lane
If the substring start index and length overflow when added together, substring() misbehaved, either throwing a bogus "negative substring length" error on a case that should succeed, or failing to complain that a negative length is negative (and instead returning the whole string, in most cases). Unsurprisingly, the text, bytea, and bit variants of the function all had this issue. Rearrange the logic to ensure that negative lengths are always rejected, and add an overflow check to handle the other case. Also install similar guards into detoast_attr_slice() (nee heap_tuple_untoast_attr_slice()), since it's far from clear that no other code paths leading to that function could pass it values that would overflow. Patch by myself and Pavel Stehule, per bug #16804 from Rafi Shamim. Back-patch to v11. While these bugs are old, the common/int.h infrastructure for overflow-detecting arithmetic didn't exist before commit 4d6ad3125, and it doesn't seem like these misbehaviors are bad enough to justify developing a standalone fix for the older branches. Discussion: https://postgr.es/m/16804-f4eeeb6c11ba71d4@postgresql.org
2020-12-30Fix up usage of krb_server_keyfile GUC parameter.Tom Lane
secure_open_gssapi() installed the krb_server_keyfile setting as KRB5_KTNAME unconditionally, so long as it's not empty. However, pg_GSS_recvauth() only installed it if KRB5_KTNAME wasn't set already, leading to a troubling inconsistency: in theory, clients could see different sets of server principal names depending on whether they use GSSAPI encryption. Always using krb_server_keyfile seems like the right thing, so make both places do that. Also fix up secure_open_gssapi()'s lack of a check for setenv() failure --- it's unlikely, surely, but security-critical actions are no place to be sloppy. Also improve the associated documentation. This patch does nothing about secure_open_gssapi()'s use of setenv(), and indeed causes pg_GSS_recvauth() to use it too. That's nominally against project portability rules, but since this code is only built with --with-gssapi, I do not feel a need to do something about this in the back branches. A fix will be forthcoming for HEAD though. Back-patch to v12 where GSSAPI encryption was introduced. The dubious behavior in pg_GSS_recvauth() goes back further, but it didn't have anything to be inconsistent with, so let it be. Discussion: https://postgr.es/m/2187460.1609263156@sss.pgh.pa.us
2020-12-28Fix assorted issues in backend's GSSAPI encryption support.Tom Lane
Unrecoverable errors detected by GSSAPI encryption can't just be reported with elog(ERROR) or elog(FATAL), because attempting to send the error report to the client is likely to lead to infinite recursion or loss of protocol sync. Instead make this code do what the SSL encryption code has long done, which is to just report any such failure to the server log (with elevel COMMERROR), then pretend we've lost the connection by returning errno = ECONNRESET. Along the way, fix confusion about whether message translation is done by pg_GSS_error() or its callers (the latter should do it), and make the backend version of that function work more like the frontend version. Avoid allocating the port->gss struct until it's needed; we surely don't need to allocate it in the postmaster. Improve logging of "connection authorized" messages with GSS enabled. (As part of this, I back-patched the code changes from dc11f31a1.) Make BackendStatusShmemSize() account for the GSS-related space that will be allocated by CreateSharedBackendStatus(). This omission could possibly cause out-of-shared-memory problems with very high max_connections settings. Remove arbitrary, pointless restriction that only GSS authentication can be used on a GSS-encrypted connection. Improve documentation; notably, document the fact that libpq now prefers GSS encryption over SSL encryption if both are possible. Per report from Mikael Gustavsson. Back-patch to v12 where this code was introduced. Discussion: https://postgr.es/m/e5b0b6ed05764324a2f3fe7acfc766d5@smhi.se
2020-12-28Fix inconsistent code with shared invalidations of snapshotsMichael Paquier
The code in charge of processing a single invalidation message has been using since 568d413 the structure for relation mapping messages. This had fortunately no consequence as both locate the database ID at the same location, but it could become a problem in the future if this area of the code changes. Author: Konstantin Knizhnik Discussion: https://postgr.es/m/8044c223-4d3a-2cdb-42bf-29940840ce94@postgrespro.ru Backpatch-through: 9.5
2020-12-25Invalidate acl.c caches when pg_authid changes.Noah Misch
This makes existing sessions reflect "ALTER ROLE ... [NO]INHERIT" as quickly as they have been reflecting "GRANT role_name". Back-patch to 9.5 (all supported versions). Reviewed by Nathan Bossart. Discussion: https://postgr.es/m/20201221095028.GB3777719@rfd.leadboat.com
2020-12-23Fix portability issues with parsing of recovery_target_xidMichael Paquier
The parsing of this parameter has been using strtoul(), which is not portable across platforms. On most Unix platforms, unsigned long has a size of 64 bits, while on Windows it is 32 bits. It is common in recovery scenarios to rely on the output of txid_current() or even the newer pg_current_xact_id() to get a transaction ID for setting up recovery_target_xid. The value returned by those functions includes the epoch in the computed result, which would cause strtoul() to fail where unsigned long has a size of 32 bits once the epoch is incremented. WAL records and 2PC data include only information about 32-bit XIDs and it is not possible to have XIDs across more than one epoch, so discarding the high bits from the transaction ID set has no impact on recovery. On the contrary, the use of strtoul() prevents a consistent behavior across platforms depending on the size of unsigned long. This commit changes the parsing of recovery_target_xid to use pg_strtouint64() instead, available down to 9.6. There is one TAP test stressing recovery with recovery_target_xid, where a tweak based on pg_reset{xlog,wal} is added to bump the XID epoch so as this change gets tested, as per an idea from Alexander Lakhin. Reported-by: Alexander Lakhin Discussion: https://postgr.es/m/16780-107fd0c0385b1035@postgresql.org Backpatch-through: 9.6
2020-12-21Remove "invalid concatenation of jsonb objects" error case.Tom Lane
The jsonb || jsonb operator arbitrarily rejected certain combinations of scalar and non-scalar inputs, while being willing to concatenate other combinations. This was of course quite undocumented. Rather than trying to document it, let's just remove the restriction, creating a uniform rule that unless we are handling an object-to-object concatenation, non-array inputs are converted to one-element arrays, resulting in an array-to-array concatenation. (This does not change the behavior for any case that didn't throw an error before.) Per complaint from Joel Jacobson. Back-patch to all supported branches. Discussion: https://postgr.es/m/163099.1608312033@sss.pgh.pa.us
2020-12-18Avoid memcpy() with same source and destination during relmapper init.Tom Lane
A narrow reading of the C standard says that memcpy(x,x,n) is undefined, although it's hard to envision an implementation that would really misbehave. However, analysis tools such as valgrind might whine about this; accordingly, let's band-aid relmapper.c to not do it. See also 5b630501e, d3f4e8a8a, ad7b48ea0, and other similar fixes. Apparently, none of those folk tried valgrinding initdb? This has been like this for long enough that I'm surprised it hasn't been reported before. Back-patch, just in case anybody wants to use a back branch on a platform that complains about this; we back-patched those earlier fixes too. Discussion: https://postgr.es/m/161790.1608310142@sss.pgh.pa.us
2020-11-20Adjust DSM and DSA slot usage constants (back-patch).Thomas Munro
1. Previously, a DSA area would create up to four segments at each size before doubling the size. After this commit, it will create only two at each size, so it ramps up faster and therefore needs fewer slots. 2. Previously, the total limit on DSM slots allowed for 2 per connection. Switch to 5 per connection. This back-patches commit d061ea21 from release 13 into 10-12 based on a field complaint. Discussion: https://postgr.es/m/CAO03teA%2BjE1qt5iWDWzHqaufqBsF6EoOgZphnazps_tr_jDPZA%40mail.gmail.com Discussion: https://postgr.es/m/CA%2BhUKGL6H2BpGbiF7Lj6QiTjTGyTLW_vLR%3DSn2tEBeTcYXiMKw%40mail.gmail.com
2020-11-10Fix and simplify some usages of TimestampDifference().Tom Lane
Introduce TimestampDifferenceMilliseconds() to simplify callers that would rather have the difference in milliseconds, instead of the select()-oriented seconds-and-microseconds format. This gets rid of at least one integer division per call, and it eliminates some apparently-easy-to-mess-up arithmetic. Two of these call sites were in fact wrong: * pg_prewarm's autoprewarm_main() forgot to multiply the seconds by 1000, thus ending up with a delay 1000X shorter than intended. That doesn't quite make it a busy-wait, but close. * postgres_fdw's pgfdw_get_cleanup_result() thought it needed to compute microseconds not milliseconds, thus ending up with a delay 1000X longer than intended. Somebody along the way had noticed this problem but misdiagnosed the cause, and imposed an ad-hoc 60-second limit rather than fixing the units. This was relatively harmless in context, because we don't care that much about exactly how long this delay is; still, it's wrong. There are a few more callers of TimestampDifference() that don't have a direct need for seconds-and-microseconds, but can't use TimestampDifferenceMilliseconds() either because they do need microsecond precision or because they might possibly deal with intervals long enough to overflow 32-bit milliseconds. It might be worth inventing another API to improve that, but that seems outside the scope of this patch; so those callers are untouched here. Given the fact that we are fixing some bugs, and the likelihood that future patches might want to back-patch code that uses this new API, back-patch to all supported branches. Alexey Kondratov and Tom Lane Discussion: https://postgr.es/m/3b1c053a21c07c1ed5e00be3b2b855ef@postgrespro.ru
2020-11-04Enable hash partitioning of text arraysPeter Eisentraut
hash_array_extended() needs to pass PG_GET_COLLATION() to the hash function of the element type. Otherwise, the hash function of a collation-aware data type such as text will error out, since the introduction of nondeterministic collation made hash functions require a collation, too. The consequence of this is that before this change, hash partitioning using an array over text in the partition key would not work. Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://www.postgresql.org/message-id/flat/32c1fdae-95c6-5dc6-058a-a90330a3b621%40enterprisedb.com
2020-10-25Fix incorrect parameter name in a function header commentDavid Rowley
Author: Zhijie Hou Discussion: https://postgr.es/m/14cd74ea00204cc8a7ea5d738ac82cd1@G08CNEXMBPEKD05.g08.fujitsu.local Backpatch-through: 12, where the mistake was introduced
2020-10-12Fix memory leak when guc.c decides a setting can't be applied now.Tom Lane
The prohibitValueChange code paths in set_config_option(), which are executed whenever we re-read a PGC_POSTMASTER variable from postgresql.conf, neglected to free anything before exiting. Thus we'd leak the proposed new value of a PGC_STRING variable, as noted by BoChen in bug #16666. For all variable types, if the check hook creates an "extra" chunk, we'd also leak that. These are malloc not palloc chunks, so there is no mechanism for recovering the leaks before process exit. Fortunately, the values are typically not very large, meaning you'd have to go through an awful lot of SIGHUP configuration-reload cycles to make the leakage amount to anything. Still, for a long-lived postmaster process it could potentially be a problem. Oversight in commit 2594cf0e8. Back-patch to all supported branches. Discussion: https://postgr.es/m/16666-2c41a4eec61b03e1@postgresql.org
2020-09-30Fix handling of BC years in to_date/to_timestamp.Tom Lane
Previously, a conversion such as to_date('-44-02-01','YYYY-MM-DD') would result in '0045-02-01 BC', as the code attempted to interpret the negative year as BC, but failed to apply the correction needed for our internal handling of BC years. Fix the off-by-one problem. Also, arrange for the combination of a negative year and an explicit "BC" marker to cancel out and produce AD. This is how the negative-century case works, so it seems sane to do likewise. Continue to read "year 0000" as 1 BC. Oracle would throw an error, but we've accepted that case for a long time so I'm hesitant to change it in a back-patch. Per bug #16419 from Saeed Hubaishan. Back-patch to all supported branches. Dar Alathar-Yemen and Tom Lane Discussion: https://postgr.es/m/16419-d8d9db0a7553f01b@postgresql.org
2020-08-15Move new LOCKTAG_DATABASE_FROZEN_IDS to end of enum LockTagType.Noah Misch
Several PGXN modules reference LockTagType values; renumbering would force a recompile of those modules. Oversight in back-patch of today's commit 566372b3d6435639e4cc4476d79b8505a0297c87. Back-patch to released branches, v12 through 9.5. Reported by Tom Lane. Discussion: https://postgr.es/m/921383.1597523945@sss.pgh.pa.us
2020-08-15Prevent concurrent SimpleLruTruncate() for any given SLRU.Noah Misch
The SimpleLruTruncate() header comment states the new coding rule. To achieve this, add locktype "frozenid" and two LWLocks. This closes a rare opportunity for data loss, which manifested as "apparent wraparound" or "could not access status of transaction" errors. Data loss is more likely in pg_multixact, due to released branches' thin margin between multiStopLimit and multiWrapLimit. If a user's physical replication primary logged ": apparent wraparound" messages, the user should rebuild standbys of that primary regardless of symptoms. At less risk is a cluster having emitted "not accepting commands" errors or "must be vacuumed" warnings at some point. One can test a cluster for this data loss by running VACUUM FREEZE in every database. Back-patch to 9.5 (all supported versions). Discussion: https://postgr.es/m/20190218073103.GA1434723@rfd.leadboat.com
2020-08-14Fix postmaster's behavior during smart shutdown.Tom Lane
Up to now, upon receipt of a SIGTERM ("smart shutdown" command), the postmaster has immediately killed all "optional" background processes, and subsequently refused to launch new ones while it's waiting for foreground client processes to exit. No doubt this seemed like an OK policy at some point; but it's a pretty bad one now, because it makes for a seriously degraded environment for the remaining clients: * Parallel queries are killed, and new ones fail to launch. (And our parallel-query infrastructure utterly fails to deal with the case in a reasonable way --- it just hangs waiting for workers that are not going to arrive. There is more work needed in that area IMO.) * Autovacuum ceases to function. We can tolerate that for awhile, but if bulk-update queries continue to run in the surviving client sessions, there's eventually going to be a mess. In the worst case the system could reach a forced shutdown to prevent XID wraparound. * The bgwriter and walwriter are also stopped immediately, likely resulting in performance degradation. Hence, let's rearrange things so that the only immediate change in behavior is refusing to let in new normal connections. Once the last normal connection is gone, shut everything down as though we'd received a "fast" shutdown. To implement this, remove the PM_WAIT_BACKUP and PM_WAIT_READONLY states, instead staying in PM_RUN or PM_HOT_STANDBY while normal connections remain. A subsidiary state variable tracks whether or not we're letting in new connections in those states. This also allows having just one copy of the logic for killing child processes in smart and fast shutdown modes. I moved that logic into PostmasterStateMachine() by inventing a new state PM_STOP_BACKENDS. Back-patch to 9.6 where parallel query was added. In principle this'd be a good idea in 9.5 as well, but the risk/reward ratio is not as good there, since lack of autovacuum is not a problem during typical uses of smart shutdown. Per report from Bharath Rupireddy. Patch by me, reviewed by Thomas Munro Discussion: https://postgr.es/m/CALj2ACXAZ5vKxT9P7P89D87i3MDO9bfS+_bjMHgnWJs8uwUOOw@mail.gmail.com
2020-07-31Fix recently-introduced performance problem in ts_headline().Tom Lane
The new hlCover() algorithm that I introduced in commit c9b0c678d turns out to potentially take O(N^2) or worse time on long documents, if there are many occurrences of individual query words but few or no substrings that actually satisfy the query. (One way to hit this behavior is with a "common_word & rare_word" type of query.) This seems unavoidable given the original goal of checking every substring of the document, so we have to back off that idea. Fortunately, it seems unlikely that anyone would really want headlines spanning all of a long document, so we can avoid the worse-than-linear behavior by imposing a maximum length of substring that we'll consider. For now, just hard-wire that maximum length as a multiple of max_words times max_fragments. Perhaps at some point somebody will argue for exposing it as a ts_headline parameter, but I'm hesitant to make such a feature addition in a back-patched bug fix. I also noted that the hlFirstIndex() function I'd added in that commit was unnecessarily stupid: it really only needs to check whether a HeadlineWordEntry's item pointer is null or not. This wouldn't make all that much difference in typical cases with queries having just a few terms, but a cycle shaved is a cycle earned. In addition, add a CHECK_FOR_INTERRUPTS call in TS_execute_recurse. This ensures that hlCover's loop is cancellable if it manages to take a long time, and it may protect some other TS_execute callers as well. Back-patch to 9.6 as the previous commit was. I also chose to add the CHECK_FOR_INTERRUPTS call to 9.5. The old hlCover() algorithm seems to avoid the O(N^2) behavior, at least on the test case I tried, but nonetheless it's not very quick on a long document. Per report from Stephen Frost. Discussion: https://postgr.es/m/20200724160535.GW12375@tamriel.snowman.net
2020-07-21neqjoinsel must now pass through collation to eqjoinsel.Tom Lane
Since commit 044c99bc5, eqjoinsel passes the passed-in collation to any operators it invokes. However, neqjoinsel failed to pass on whatever collation it got, so that if we invoked a collation-dependent operator via that code path, we'd get "could not determine which collation to use for string comparison" or the like. Per report from Justin Pryzby. Back-patch to v12, like the previous commit. Discussion: https://postgr.es/m/20200721191606.GL5748@telsasoft.com
2020-07-17Fix whitespacePeter Eisentraut
2020-07-11Forbid numeric NaN in jsonpathAlexander Korotkov
SQL standard doesn't define numeric Inf or NaN values. It appears even more ridiculous to support then in jsonpath assuming JSON doesn't support these values as well. This commit forbids returning NaN from .double(), which was previously allowed. NaN can't be result of inner-jsonpath computation over non-NaNs. So, we can not expect NaN in the jsonpath output. Reported-by: Tom Lane Discussion: https://postgr.es/m/203949.1591879542%40sss.pgh.pa.us Author: Alexander Korotkov Reviewed-by: Tom Lane Backpatch-through: 12
2020-07-11Improve error reporting for jsonpath .double() methodAlexander Korotkov
When jsonpath .double() method detects that numeric or string can't be converted to double precision, it throws an error. This commit makes these errors explicitly express the reason of failure. Discussion: https://postgr.es/m/CAPpHfdtqJtiSXkP7tOXez18NxhLUH_-75bL8%3DOce4Ki%2Bbv7V6Q%40mail.gmail.com Author: Alexander Korotkov Reviewed-by: Tom Lane Backpatch-through: 12
2020-07-09Fix pg_current_logfile() to not emit a carriage return on Windows.Tom Lane
Due to not having our signals straight about CRLF vs. LF line termination, the output of pg_current_logfile() included a trailing \r on Windows. To fix, force the file descriptor it uses into text mode. While here, move a couple of local variable declarations to make the function's logic clearer. In v12 and v13, also back-patch the test added by 1c4e88e2f so that this function has some test coverage. However, the 004_logrotate.pl test script doesn't exist before v12, and it didn't seem worth adding to older branches just for this. Per report from Thomas Kellerer. Back-patch to v10 where this function was added. Discussion: https://postgr.es/m/412ae8da-76bb-640f-039a-f3513499e53d@gmx.net
2020-07-04Fix "ignoring return value" complaints from commit 96d1f423f9Joe Conway
The cfbot and some BF animals are complaining about the previous read_binary_file commit because of ignoring return value of ‘fread’. So let's make everyone happy by testing the return value even though not strictly needed. Reported by Justin Pryzby, and suggested patch by Tom Lane. Backpatched to v11 same as the previous commit. Reported-By: Justin Pryzby Reviewed-By: Tom Lane Discussion: https://postgr.es/m/flat/969b8d82-5bb2-5fa8-4eb1-f0e685c5d736%40joeconway.com Backpatch-through: 11
2020-07-04Read until EOF vice stat-reported size in read_binary_fileJoe Conway
read_binary_file(), used by SQL functions pg_read_file() and friends, uses stat to determine file length to read, when not passed an explicit length as an argument. This is problematic, for example, if the file being read is a virtual file with a stat-reported length of zero. Arrange to read until EOF, or StringInfo data string lenth limit, is reached instead. Original complaint and patch by me, with significant review, corrections, advice, and code optimizations by Tom Lane. Backpatched to v11. Prior to that only paths relative to the data and log dirs were allowed for files, so no "zero length" files were reachable anyway. Reviewed-By: Tom Lane Discussion: https://postgr.es/m/flat/969b8d82-5bb2-5fa8-4eb1-f0e685c5d736%40joeconway.com Backpatch-through: 11
2020-06-16Fix buffile.c error handling.Thomas Munro
Convert buffile.c error handling to use ereport. This fixes cases where I/O errors were indistinguishable from EOF or not reported. Also remove "%m" from error messages where errno would be bogus. While we're modifying those strings, add block numbers and short read byte counts where appropriate. Back-patch to all supported releases. Reported-by: Amit Khandekar <amitdkhan.pg@gmail.com> Reviewed-by: Melanie Plageman <melanieplageman@gmail.com> Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com> Reviewed-by: Robert Haas <robertmhaas@gmail.com> Reviewed-by: Ibrar Ahmed <ibrar.ahmad@gmail.com> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/CA%2BhUKGJE04G%3D8TLK0DLypT_27D9dR8F1RQgNp0jK6qR0tZGWOw%40mail.gmail.com
2020-06-13Fix behavior of float aggregates for single Inf or NaN inputs.Tom Lane
When there is just one non-null input value, and it is infinity or NaN, aggregates such as stddev_pop and covar_pop should produce a NaN result, because the calculation is not well-defined. They used to do so, but since we adopted Youngs-Cramer aggregation in commit e954a727f, they produced zero instead. That's an oversight, so fix it. Add tests exercising these edge cases. Affected aggregates are var_pop(double precision) stddev_pop(double precision) var_pop(real) stddev_pop(real) regr_sxx(double precision,double precision) regr_syy(double precision,double precision) regr_sxy(double precision,double precision) regr_r2(double precision,double precision) regr_slope(double precision,double precision) regr_intercept(double precision,double precision) covar_pop(double precision,double precision) corr(double precision,double precision) Back-patch to v12 where the behavior change was accidentally introduced. Report and patch by me; thanks to Dean Rasheed for review. Discussion: https://postgr.es/m/353062.1591898766@sss.pgh.pa.us
2020-06-11Fix mishandling of NaN counts in numeric_[avg_]combine.Tom Lane
When merging two NumericAggStates, the code missed adding the new state's NaNcount unless its N was also nonzero; since those counts are independent, this is wrong. This would only have visible effect if some partial aggregate scans found only NaNs while earlier ones found only non-NaNs; then we could end up falsely deciding that there were no NaNs and fail to return a NaN final result as expected. That's pretty improbable, so it's no surprise this hasn't been reported from the field. Still, it's a bug. I didn't try to produce a regression test that would show the bug, but I did notice that these functions weren't being reached at all in our regression tests, so I improved the tests to at least exercise them. With these additions, I see pretty complete code coverage on the aggregation-related functions in numeric.c. Back-patch to 9.6 where this code was introduced. (I only added the improved test case as far back as v10, though, since the relevant part of aggregates.sql isn't there at all in 9.6.)
2020-06-10Update description of parameter password_encryptionPeter Eisentraut
The previous description string still described the pre-PostgreSQL 10 (pre eb61136dc75a76caef8460fa939244d8593100f2) behavior of selecting between encrypted and unencrypted, but it is now choosing between encryption algorithms.
2020-06-05Use query collation, not column's collation, while examining statistics.Tom Lane
Commit 5e0928005 changed the planner so that, instead of blindly using DEFAULT_COLLATION_OID when invoking operators for selectivity estimation, it would use the collation of the column whose statistics we're considering. This was recognized as still being not quite the right thing, but it seemed like a good incremental improvement. However, shortly thereafter we introduced nondeterministic collations, and that creates cases where operators can fail if they're passed the wrong collation. We don't want planning to fail in cases where the query itself would work, so this means that we *must* use the query's collation when invoking operators for estimation purposes. The only real problem this creates is in ineq_histogram_selectivity, where the binary search might produce a garbage answer if we perform comparisons using a different collation than the column's histogram is ordered with. However, when the query's collation is significantly different from the column's default collation, the estimate we previously generated would be pretty irrelevant anyway; so it's not clear that this will result in noticeably worse estimates in practice. (A follow-on patch will improve this situation in HEAD, but it seems too invasive for back-patch.) The patch requires changing the signatures of mcv_selectivity and allied functions, which are exported and very possibly are used by extensions. In HEAD, I just did that, but an API/ABI break of this sort isn't acceptable in stable branches. Therefore, in v12 the patch introduces "mcv_selectivity_ext" and so on, with signatures matching HEAD, and makes the old functions into wrappers that assume DEFAULT_COLLATION_OID should be used. That does not match the prior behavior, but it should avoid risk of failure in most cases. (In practice, I think most extension datatypes aren't collation-aware, so the change probably doesn't matter to them.) Per report from James Lucas. Back-patch to v12 where the problem was introduced. Discussion: https://postgr.es/m/CAAFmbbOvfi=wMM=3qRsPunBSLb8BFREno2oOzSBS=mzfLPKABw@mail.gmail.com
2020-06-04Reject "23:59:60.nnn" in datetime input.Tom Lane
It's intentional that we don't allow values greater than 24 hours, while we do allow "24:00:00" as well as "23:59:60" as inputs. However, the range check was miscoded in such a way that it would accept "23:59:60.nnn" with a nonzero fraction. For time or timetz, the stored result would then be greater than "24:00:00" which would fail dump/reload, not to mention possibly confusing other operations. Fix by explicitly calculating the result and making sure it does not exceed 24 hours. (This calculation is redundant with what will happen later in tm2time or tm2timetz. Maybe someday somebody will find that annoying enough to justify refactoring to avoid the duplication; but that seems too invasive for a back-patched bug fix, and the cost is probably unmeasurable anyway.) Note that this change also rejects such input as the time portion of a timestamp(tz) value. Back-patch to v10. The bug is far older, but to change this pre-v10 we'd need to ensure that the logic behaves sanely with float timestamps, which is possibly nontrivial due to roundoff considerations. Doesn't really seem worth troubling with. Per report from Christoph Berg. Discussion: https://postgr.es/m/20200520125807.GB296739@msg.df7cb.de
2020-06-01Fix use-after-release mistake in currtid() and currtid2() for viewsMichael Paquier
This issue has been present since the introduction of this code as of a3519a2 from 2002, and has been found by buildfarm member prion that uses RELCACHE_FORCE_RELEASE via the tests introduced recently in e786be5. Discussion: https://postgr.es/m/20200601022055.GB4121@paquier.xyz Backpatch-through: 9.5
2020-06-01Fix crashes with currtid() and currtid2()Michael Paquier
A relation that has no storage initializes rd_tableam to NULL, which caused those two functions to crash because of a pointer dereference. Note that in 11 and older versions, this has always failed with a confusing error "could not open file". These two functions are used by the Postgres ODBC driver, which requires them only when connecting to a backend strictly older than 8.1. When connected to 8.2 or a newer version, the driver uses a RETURNING clause instead whose support has been added in 8.2, so it should be possible to just remove both functions in the future. This is left as an issue to address later. While on it, add more regression tests for those functions as we never really had coverage for them, and for aggregates of TIDs. Reported-by: Jaime Casanova, via sqlsmith Author: Michael Paquier Reviewed-by: Álvaro Herrera Discussion: https://postgr.es/m/CAJGNTeO93u-5APMga6WH41eTZ3Uee9f3s8dCpA-GSSqNs1b=Ug@mail.gmail.com Backpatch-through: 12
2020-05-28Add CHECK_FOR_INTERRUPTS() to the repeat() functionJoe Conway
The repeat() function loops for potentially a long time without ever checking for interrupts. This prevents, for example, a query cancel from interrupting until the work is all done. Fix by inserting a CHECK_FOR_INTERRUPTS() into the loop. Backpatch to all supported versions. Discussion: https://www.postgresql.org/message-id/flat/8692553c-7fe8-17d9-cbc1-7cddb758f4c6%40joeconway.com
2020-05-26Add lcov exclusion markers to jsonpath scannerPeter Eisentraut
This was done for all scanners in 421167362242ce1fb46d6d720798787e7cd65aad but not added to the new one.
2020-05-14Fix the MSVC build for versions 2015 and later.Amit Kapila
Visual Studio 2015 and later versions should still be able to do the same as Visual Studio 2012, but the declaration of locale_name is missing in _locale_t, causing the code compilation to fail, hence this falls back instead on to enumerating all system locales by using EnumSystemLocalesEx to find the required locale name.  If the input argument is in Unix-style then we can get ISO Locale name directly by using GetLocaleInfoEx() with LCType as LOCALE_SNAME. In passing, change the documentation references of the now obsolete links. Note that this problem occurs only with NLS enabled builds. Author: Juan José Santamaría Flecha, Davinder Singh and Amit Kapila Reviewed-by: Ranier Vilela and Amit Kapila Backpatch-through: 9.5 Discussion: https://postgr.es/m/CAHzhFSFoJEWezR96um4-rg5W6m2Rj9Ud2CNZvV4NWc9tXV7aXQ@mail.gmail.com
2020-05-07Fix YA text phrase search bug.Tom Lane
checkcondition_str() failed to report multiple matches for a prefix pattern correctly: it would dutifully merge the match positions, but then after exiting that loop, if the last prefix-matching word had had no suitable positions, it would report there were no matches. The upshot would be failing to recognize a match that the query should match. It looks like you need all of these conditions to see the bug: * a phrase search (else we don't ask for match position details) * a prefix search item (else we don't get to this code) * a weight restriction (else checkclass_str won't fail) Noted while investigating a problem report from Pavel Borisov, though this is distinct from the issue he was on about. Back-patch to 9.6 where phrase search was added.
2020-05-01Get rid of trailing semicolons in C macro definitions.Tom Lane
Writing a trailing semicolon in a macro is almost never the right thing, because you almost always want to write a semicolon after each macro call instead. (Even if there was some reason to prefer not to, pgindent would probably make a hash of code formatted that way; so within PG the rule should basically be "don't do it".) Thus, if we have a semi inside the macro, the compiler sees "something;;". Much of the time the extra empty statement is harmless, but it could lead to mysterious syntax errors at call sites. In perhaps an overabundance of neatnik-ism, let's run around and get rid of the excess semicolons whereever possible. The only thing worse than a mysterious syntax error is a mysterious syntax error that only happens in the back branches; therefore, backpatch these changes where relevant, which is most of them because most of these mistakes are old. (The lack of reported problems shows that this is largely a hypothetical issue, but still, it could bite us in some future patch.) John Naylor and Tom Lane Discussion: https://postgr.es/m/CACPNZCs0qWTqJ2QUSGJ07B7uvAvzMb-KbG2q+oo+J3tsWN5cqw@mail.gmail.com
2020-04-27Fix full text search to handle NOT above a phrase search correctly.Tom Lane
Queries such as '!(foo<->bar)' failed to find matching rows when implemented as a GiST or GIN index search. That's because of failing to handle phrase searches as tri-valued when considering a query without any position information for the target tsvector. We can only say that the phrase operator might match, not that it does match; and therefore its NOT also might match. The previous coding incorrectly inverted the approximate phrase result to decide that there was certainly no match. To fix, we need to make TS_phrase_execute return a real ternary result, and then bubble that up accurately in TS_execute. As long as we have to do that anyway, we can simplify the baroque things TS_phrase_execute was doing internally to manage tri-valued searching with only a bool as explicit result. For now, I left the externally-visible result of TS_execute as a plain bool. There do not appear to be any outside callers that need to distinguish a three-way result, given that they passed in a flag saying what to do in the absence of position data. This might need to change someday, but we wouldn't want to back-patch such a change. Although tsginidx.c has its own TS_execute_ternary implementation for use at upper index levels, that sadly managed to get this case wrong as well :-(. Fixing it is a lot easier fortunately. Per bug #16388 from Charles Offenbacher. Back-patch to 9.6 where phrase search was introduced. Discussion: https://postgr.es/m/16388-98cffba38d0b7e6e@postgresql.org
2020-04-20Allow pg_read_all_stats to access all stats views againMagnus Hagander
The views pg_stat_progress_* had not gotten the memo that pg_read_all_stats is supposed to be able to read all statistics. Also make a pass over all text-returning pg_stat_xyz functions that could return "insufficient privilege" and make sure they also respect pg_read_all_status. Reported-by: Andrey M. Borodin Reviewed-by: Andrey M. Borodin, Kyotaro Horiguchi Discussion: https://postgr.es/m/13145F2F-8458-4977-9D2D-7B2E862E5722@yandex-team.ru
2020-04-07Fix circle_in to accept "(x,y),r" as it's advertised to do.Tom Lane
Our documentation describes four allowed input syntaxes for circles, but the regression tests tried only three ... with predictable consequences. Remarkably, this has been wrong since the circle datatype was added in 1997, but nobody noticed till now. David Zhang, with some help from me Discussion: https://postgr.es/m/332c47fa-d951-7574-b5cc-a8f7f7201202@highgo.ca
2020-04-07Adjust bytea get_bit/set_bit to cope with bytea strings > 256MB.Tom Lane
Since the existing bit number argument can't exceed INT32_MAX, it's not possible for these functions to manipulate bits beyond the first 256MB of a bytea value. However, it'd be good if they could do at least that much, and not fall over entirely for longer bytea values. Adjust the comparisons to be done in int64 arithmetic so that works. Also tweak the error reports to show sane values in case of overflow. Also add some test cases to improve the miserable code coverage of these functions. Apply patch to back branches only; HEAD has a better solution as of commit 26a944cf2. Extracted from a much larger patch by Movead Li Discussion: https://postgr.es/m/20200312115135445367128@highgo.ca
2020-04-06Preserve clustered index after rewrites with ALTER TABLEMichael Paquier
A table rewritten by ALTER TABLE would lose tracking of an index usable for CLUSTER. This setting is tracked by pg_index.indisclustered and is controlled by ALTER TABLE, so some extra work was needed to restore it properly. Note that ALTER TABLE only marks the index that can be used for clustering, and does not do the actual operation. Author: Amit Langote, Justin Pryzby Reviewed-by: Ibrar Ahmed, Michael Paquier Discussion: https://postgr.es/m/20200202161718.GI13621@telsasoft.com Backpatch-through: 9.5
2020-03-31Teach pg_ls_dir_files() to ignore ENOENT failures from stat().Tom Lane
Buildfarm experience shows that this function can fail with ENOENT if some other process unlinks a file between when we read the directory entry and when we try to stat() it. The problem is old but we had not noticed it until 085b6b667 added regression test coverage. To fix, just ignore ENOENT failures. There is one other case that this might hide: a symlink that points to nowhere. That seems okay though, at least better than erroring. Back-patch to v10 where this function was added, since the regression test cases were too. Discussion: https://postgr.es/m/20200308173103.GC1357@telsasoft.com
2020-03-28Ensure snapshot is registered within ScanPgRelation().Andres Freund
In 9.4 I added support to use a historical snapshot in ScanPgRelation(), while adding logical decoding. Unfortunately a conflict with the concurrent removal of SnapshotNow was incorrectly resolved, leading to an unregistered snapshot being used. It is not correct to use an unregistered (or non-active) snapshot for anything non-trivial, because catalog invalidations can cause the snapshot to be invalidated. Luckily it seems unlikely to actively cause problems in practice, as ScanPgRelation() requires that we already have a lock on the relation, we only look for a single row, and we don't appear to rely on the result's tid to be correct. It however is clearly wrong and potential negative consequences would likely be hard to find. So it seems worth backpatching the fix, even without a concrete hazard. Discussion: https://postgr.es/m/20200229052459.wzhqnbhrriezg4v2@alap3.anarazel.de Backpatch: 9.5-
2020-03-24Re-implement the ereport() macro using __VA_ARGS__.Tom Lane
Now that we require C99, we can depend on __VA_ARGS__ to work, and revising ereport() to use it has several significant benefits: * The extra parentheses around the auxiliary function calls are now optional. Aside from being a bit less ugly, this removes a common gotcha for new contributors, because in some cases the compiler errors you got from forgetting them were unintelligible. * The auxiliary function calls are now evaluated as a comma expression list rather than as extra arguments to errfinish(). This means that compilers can be expected to warn about no-op expressions in the list, allowing detection of several other common mistakes such as forgetting to add errmsg(...) when converting an elog() call to ereport(). * Unlike the situation with extra function arguments, comma expressions are guaranteed to be evaluated left-to-right, so this removes platform dependency in the order of the auxiliary function calls. While that dependency hasn't caused us big problems in the past, this change does allow dropping some rather shaky assumptions around errcontext() domain handling. There's no intention to make wholesale changes of existing ereport calls, but as proof-of-concept this patch removes the extra parens from a couple of calls in postgres.c. While new code can be written either way, code intended to be back-patched will need to use extra parens for awhile yet. It seems worth back-patching this change into v12, so as to reduce the window where we have to be careful about that by one year. Hence, this patch is careful to preserve ABI compatibility; a followup HEAD-only patch will make some additional simplifications. Andres Freund and Tom Lane Discussion: https://postgr.es/m/CA+fd4k6N8EjNvZpM8nme+y+05mz-SM8Z_BgkixzkA34R+ej0Kw@mail.gmail.com
2020-03-22Revert "Skip WAL for new relfilenodes, under wal_level=minimal."Noah Misch
This reverts commit cb2fd7eac285b1b0a24eeb2b8ed4456b66c5a09f. Per numerous buildfarm members, it was incompatible with parallel query, and a test case assumed LP64. Back-patch to 9.5 (all supported versions). Discussion: https://postgr.es/m/20200321224920.GB1763544@rfd.leadboat.com
2020-03-21Skip WAL for new relfilenodes, under wal_level=minimal.Noah Misch
Until now, only selected bulk operations (e.g. COPY) did this. If a given relfilenode received both a WAL-skipping COPY and a WAL-logged operation (e.g. INSERT), recovery could lose tuples from the COPY. See src/backend/access/transam/README section "Skipping WAL for New RelFileNode" for the new coding rules. Maintainers of table access methods should examine that section. To maintain data durability, just before commit, we choose between an fsync of the relfilenode and copying its contents to WAL. A new GUC, wal_skip_threshold, guides that choice. If this change slows a workload that creates small, permanent relfilenodes under wal_level=minimal, try adjusting wal_skip_threshold. Users setting a timeout on COMMIT may need to adjust that timeout, and log_min_duration_statement analysis will reflect time consumption moving to COMMIT from commands like COPY. Internally, this requires a reliable determination of whether RollbackAndReleaseCurrentSubTransaction() would unlink a relation's current relfilenode. Introduce rd_firstRelfilenodeSubid. Amend the specification of rd_createSubid such that the field is zero when a new rel has an old rd_node. Make relcache.c retain entries for certain dropped relations until end of transaction. Back-patch to 9.5 (all supported versions). This introduces a new WAL record type, XLOG_GIST_ASSIGN_LSN, without bumping XLOG_PAGE_MAGIC. As always, update standby systems before master systems. This changes sizeof(RelationData) and sizeof(IndexStmt), breaking binary compatibility for affected extensions. (The most recent commit to affect the same class of extensions was 089e4d405d0f3b94c74a2c6a54357a84a681754b.) Kyotaro Horiguchi, reviewed (in earlier, similar versions) by Robert Haas. Heikki Linnakangas and Michael Paquier implemented earlier designs that materially clarified the problem. Reviewed, in earlier designs, by Andrew Dunstan, Andres Freund, Alvaro Herrera, Tom Lane, Fujii Masao, and Simon Riggs. Reported by Martijn van Oosterhout. Discussion: https://postgr.es/m/20150702220524.GA9392@svana.org