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* Don't forget to flush XLOG_PARAMETER_CHANGE record.Fujii Masao2014-03-26
| | | | Backpatch to 9.0 where XLOG_PARAMETER_CHANGE record was instroduced.
* Fix typos in pg_basebackup documentationMagnus Hagander2014-03-25
| | | | Joshua Tolley
* Address ccvalid/ccnoinherit in TupleDesc support functions.Noah Misch2014-03-23
| | | | | | | | | equalTupleDescs() neglected both of these ConstrCheck fields, and CreateTupleDescCopyConstr() neglected ccnoinherit. At this time, the only known behavior defect resulting from these omissions is constraint exclusion disregarding a CHECK constraint validated by an ALTER TABLE VALIDATE CONSTRAINT statement issued earlier in the same transaction. Back-patch to 9.2, where these fields were introduced.
* Properly check for readdir/closedir() failuresBruce Momjian2014-03-21
| | | | | | | Clear errno before calling readdir() and handle old MinGW errno bug while adding full test coverage for readdir/closedir failures. Backpatch through 8.4.
* Fix memory leak during regular expression execution.Tom Lane2014-03-19
| | | | | | | | For a regex containing backrefs, pg_regexec() might fail to free all the sub-DFAs that were created during execution, resulting in a permanent (session lifespan) memory leak. Problem was introduced by me in commit 587359479acbbdc95c8e37da40707e37097423f5. Per report from Sandro Santilli; diagnosis by Greg Stark.
* Stamp 9.2.8.REL9_2_8Tom Lane2014-03-17
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* Release notes for 9.3.4, 9.2.8, 9.1.13, 9.0.17, 8.4.21.Tom Lane2014-03-17
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* Fix bug in clean shutdown of walsender that pg_receiving is connecting to.Fujii Masao2014-03-17
| | | | | | | | | | | | | | On clean shutdown, walsender waits for all WAL to be replicated to a standby, and exits. It determined whether that replication had been completed by checking whether its sent location had been equal to a standby's flush location. Unfortunately this condition never becomes true when the standby such as pg_receivexlog which always returns an invalid flush location is connecting to walsender, and then walsender waits forever. This commit changes walsender so that it just checks a standby's write location if a flush location is invalid. Back-patch to 9.1 where enough infrastructure for this exists.
* plperl: Fix memory leak in hek2cstrAlvaro Herrera2014-03-16
| | | | | | | | Backpatch all the way back to 9.1, where it was introduced by commit 50d89d42. Reported by Sergey Burladyan in #9223 Author: Alex Hunsaker
* Translation updatesPeter Eisentraut2014-03-16
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* Fix unportable shell-script syntax in pg_upgrade's test.sh.Tom Lane2014-03-16
| | | | | | | | | | | | | I discovered the hard way that on some old shells, the locution FOO="" unset FOO does not behave the same as FOO=""; unset FOO and in fact leaves FOO set to an empty string. test.sh was inconsistently spelling it different ways on adjacent lines. This got broken relatively recently, in commit c737a2e56, so the lack of field reports to date doesn't represent a lot of evidence that the problem is rare.
* Fix advertised dispsize for libpq's sslmode connection parameter.Tom Lane2014-03-16
| | | | | | | | | | "8" was correct back when "disable" was the longest allowed value, but since "verify-full" was added, it should be "12". Given the lack of complaints, I wouldn't be surprised if nobody is actually using these values ... but still, if they're in the API, they should be right. Noticed while pursuing a different problem. It's been wrong for quite a long time, so back-patch to all supported branches.
* Update time zone data files to tzdata release 2014a.Tom Lane2014-03-15
| | | | DST law changes in Fiji, Turkey; historical changes in Israel, Ukraine.
* Prevent interrupts while reporting non-ERROR elog messages.Tom Lane2014-03-13
| | | | | | | | | | | | | | | | This should eliminate the risk of recursive entry to syslog(3), which appears to be the cause of the hang reported in bug #9551 from James Morton. Arguably, the real problem here is auth.c's willingness to turn on ImmediateInterruptOK while executing fairly wide swaths of backend code. We may well need to work at narrowing the code ranges in which the authentication_timeout interrupt is enabled. For the moment, though, this is a cheap and reasonably noninvasive fix for a field-reported failure; the other approach would be complex and not necessarily bug-free itself. Back-patch to all supported branches.
* Avoid transaction-commit race condition while receiving a NOTIFY message.Tom Lane2014-03-13
| | | | | | | | | | | | | | | | | | | | | | | | Use TransactionIdIsInProgress, then TransactionIdDidCommit, to distinguish whether a NOTIFY message's originating transaction is in progress, committed, or aborted. The previous coding could accept a message from a transaction that was still in-progress according to the PGPROC array; if the client were fast enough at starting a new transaction, it might fail to see table rows added/updated by the message-sending transaction. Which of course would usually be the point of receiving the message. We noted this type of race condition long ago in tqual.c, but async.c overlooked it. The race condition probably cannot occur unless there are multiple NOTIFY senders in action, since an individual backend doesn't send NOTIFY signals until well after it's done committing. But if two senders commit in close succession, it's certainly possible that we could see the second sender's message within the race condition window while responding to the signal from the first one. Per bug #9557 from Marko Tiikkaja. This patch is slightly more invasive than what he proposed, since it removes the now-redundant TransactionIdDidAbort call. Back-patch to 9.0, where the current NOTIFY implementation was introduced.
* In WAL replay, restore GIN metapage unconditionally to avoid torn page.Heikki Linnakangas2014-03-12
| | | | | | | | | | | | | | | | We don't take a full-page image of the GIN metapage; instead, the WAL record contains all the information required to reconstruct it from scratch. But to avoid torn page hazards, we must re-initialize it from the WAL record every time, even if it already has a greater LSN, similar to how normal full page images are restored. This was highly unlikely to cause any problems in practice, because the GIN metapage is small. We rely on an update smaller than a 512 byte disk sector to be atomic elsewhere, at least in pg_control. But better safe than sorry, and this would be easy to overlook if more fields are added to the metapage so that it's no longer small. Reported by Noah Misch. Backpatch to all supported versions.
* Fix tracking of psql script line numbers during \copy from another place.Tom Lane2014-03-10
| | | | | | | | | | | | | | | | | | | | | | | Commit 08146775acd8bfe0fcc509c71857abb928697171 changed do_copy() to temporarily scribble on pset.cur_cmd_source. That was a mighty ugly bit of code in any case, but in particular it broke handleCopyIn's ability to tell whether it was reading from the current script source file (in which case pset.lineno should be incremented for each line of COPY data), or from someplace else (in which case it shouldn't). The former case still worked, the latter not so much. The visible effect was that line numbers reported for errors in a script file would be wrong if there were an earlier \copy that was reading anything other than inline-in-the-script-file data. To fix, introduce another pset field that holds the file do_copy wants the COPY code to use. This is a little bit ugly, but less so than passing the file down explicitly through several layers that aren't COPY-specific. Extracted from a larger patch by Kumar Rajeev Rastogi; that patch also changes printing of COPY command tags, which is not a bug fix and shouldn't get back-patched. This particular idea was from a suggestion by Amit Khandekar, if I'm reading the thread correctly. Back-patch to 9.2 where the faulty code was introduced.
* release notes: add item missed in 9.2.5 releaseBruce Momjian2014-03-07
| | | | | | | | | Item is "Prevent errors in WAL replay due to references to uninitialized empty pages". Report and text by Andres Freund Backpatch through 9.2.
* Fix dangling smgr_owner pointer when a fake relcache entry is freed.Heikki Linnakangas2014-03-07
| | | | | | | | | | | | A fake relcache entry can "own" a SmgrRelation object, like a regular relcache entry. But when it was free'd, the owner field in SmgrRelation was not cleared, so it was left pointing to free'd memory. Amazingly this apparently hasn't caused crashes in practice, or we would've heard about it earlier. Andres found this with Valgrind. Report and fix by Andres Freund, with minor modifications by me. Backpatch to all supported versions.
* Avoid memcpy() with same source and destination address.Heikki Linnakangas2014-03-07
| | | | | | | The behavior of that is undefined, although unlikely to lead to problems in practice. Found by running regression tests with Valgrind.
* Fix name of syslog_ident GUC in docs.Heikki Linnakangas2014-03-07
| | | | Michael Paquier
* Avoid getting more than AccessShareLock when deparsing a query.Tom Lane2014-03-06
| | | | | | | | | | | | | | | | | | | | In make_ruledef and get_query_def, we have long used AcquireRewriteLocks to ensure that the querytree we are about to deparse is up-to-date and the schemas of the underlying relations aren't changing. Howwever, that function thinks the query is about to be executed, so it acquires locks that are stronger than necessary for the purpose of deparsing. Thus for example, if pg_dump asks to deparse a rule that includes "INSERT INTO t", we'd acquire RowExclusiveLock on t. That results in interference with concurrent transactions that might for example ask for ShareLock on t. Since pg_dump is documented as being purely read-only, this is unexpected. (Worse, it used to actually be read-only; this behavior dates back only to 8.1, cf commit ba4200246.) Fix this by adding a parameter to AcquireRewriteLocks to tell it whether we want the "real" execution locks or only AccessShareLock. Report, diagnosis, and patch by Dean Rasheed. Back-patch to all supported branches.
* Do wal_level and hot standby checks when doing crash-then-archive recovery.Heikki Linnakangas2014-03-05
| | | | | | | | CheckRequiredParameterValues() should perform the checks if archive recovery was requested, even if we are going to perform crash recovery first. Reported by Kyotaro HORIGUCHI. Backpatch to 9.2, like the crash-then-archive recovery mode.
* Fix lastReplayedEndRecPtr calculation when starting from shutdown checkpoint.Heikki Linnakangas2014-03-05
| | | | | | | | | | | | | | | When entering crash recovery followed by archive recovery, and the latest checkpoint is a shutdown checkpoint, and there are no more WAL records to replay before transitioning from crash to archive recovery, we would not immediately allow read-only connections in hot standby mode even if we could. That's because when starting from a shutdown checkpoint, we set lastReplayedEndRecPtr incorrectly to the record before the checkpoint record, instead of the checkpoint record itself. We don't run the redo routine of the shutdown checkpoint record, but starting recovery from it goes through the same motions, so it should be considered as replayed. Reported by Kyotaro HORIGUCHI. All versions with hot standby are affected, so backpatch to 9.0.
* Allow regex operations to be terminated early by query cancel requests.Tom Lane2014-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | The regex code didn't have any provision for query cancel; which is unsurprising given its non-Postgres origin, but still problematic since some operations can take a long time. Introduce a callback function to check for a pending query cancel or session termination request, and call it in a couple of strategic spots where we can make the regex code exit with an error indicator. If we ever actually split out the regex code as a standalone library, some additional work will be needed to let the cancel callback function be specified externally to the library. But that's straightforward (certainly so by comparison to putting the locale-dependent character classification logic on a similar arms-length basis), and there seems no need to do it right now. A bigger issue is that there may be more places than these two where we need to check for cancels. We can always add more checks later, now that the infrastructure is in place. Since there are known examples of not-terribly-long regexes that can lock up a backend for a long time, back-patch to all supported branches. I have hopes of fixing the known performance problems later, but adding query cancel ability seems like a good idea even if they were all fixed.
* Use SnapshotDirty rather than an active snapshot to probe index endpoints.Tom Lane2014-02-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If there are lots of uncommitted tuples at the end of the index range, get_actual_variable_range() ends up fetching each one and doing an MVCC visibility check on it, until it finally hits a visible tuple. This is bad enough in isolation, considering that we don't need an exact answer only an approximate one. But because the tuples are not yet committed, each visibility check does a TransactionIdIsInProgress() test, which involves scanning the ProcArray. When multiple sessions do this concurrently, the ensuing contention results in horrid performance loss. 20X overall throughput loss on not-too-complicated queries is easy to demonstrate in the back branches (though someone's made it noticeably less bad in HEAD). We can dodge the problem fairly effectively by using SnapshotDirty rather than a normal MVCC snapshot. This will cause the index probe to take uncommitted tuples as good, so that we incur only one tuple fetch and test even if there are many such tuples. The extent to which this degrades the estimate is debatable: it's possible the result is actually a more accurate prediction than before, if the endmost tuple has become committed by the time we actually execute the query being planned. In any case, it's not very likely that it makes the estimate a lot worse. SnapshotDirty will still reject tuples that are known committed dead, so we won't give bogus answers if an invalid outlier has been deleted but not yet vacuumed from the index. (Because btrees know how to mark such tuples dead in the index, we shouldn't have a big performance problem in the case that there are many of them at the end of the range.) This consideration motivates not using SnapshotAny, which was also considered as a fix. Note: the back branches were using SnapshotNow instead of an MVCC snapshot, but the problem and solution are the same. Per performance complaints from Bartlomiej Romanski, Josh Berkus, and others. Back-patch to 9.0, where the issue was introduced (by commit 40608e7f949fb7e4025c0ddd5be01939adc79eec).
* Remove broken code that tried to handle OVERLAPS with a single argument.Tom Lane2014-02-18
| | | | | | | | | | | | | | | | | | | | | | | | The SQL standard says that OVERLAPS should have a two-element row constructor on each side. The original coding of OVERLAPS support in our grammar attempted to extend that by allowing a single-element row constructor, which it internally duplicated ... or tried to, anyway. But that code has certainly not worked since our List infrastructure was rewritten in 2004, and I'm none too sure it worked before that. As it stands, it ends up building a List that includes itself, leading to assorted undesirable behaviors later in the parser. Even if it worked as intended, it'd be a bit evil because of the possibility of duplicate evaluation of a volatile function that the user had written only once. Given the lack of documentation, test cases, or complaints, let's just get rid of the idea and only support the standard syntax. While we're at it, improve the error cursor positioning for the wrong-number-of-arguments errors, and inline the makeOverlaps() function since it's only called in one place anyway. Per bug #9227 from Joshua Yanovski. Initial patch by Joshua Yanovski, extended a bit by me.
* Disable RandomizedBaseAddress on MSVC buildsMagnus Hagander2014-02-18
| | | | | | | | The ASLR in Windows 8/Windows 2012 can break PostgreSQL's shared memory. It doesn't fail every time (which is explained by the Random part in ASLR), but can fail with errors abut failing to reserve shared memory region. MauMau, reviewed by Craig Ringer
* Fix comment; checkpointer, not bgwriter, performs checkpoints since 9.2.Heikki Linnakangas2014-02-18
| | | | Amit Langote
* Translation updatesPeter Eisentraut2014-02-17
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* Stamp 9.2.7.REL9_2_7Tom Lane2014-02-17
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* Last-minute updates for release notes.Tom Lane2014-02-17
| | | | | | Add entries for security issues. Security: CVE-2014-0060 through CVE-2014-0067
* Document risks of "make check" in the regression testing instructions.Tom Lane2014-02-17
| | | | | | | | | | | | | | | | | | | | Since the temporary server started by "make check" uses "trust" authentication, another user on the same machine could connect to it as database superuser, and then potentially exploit the privileges of the operating-system user who started the tests. We should change the testing procedures to prevent this risk; but discussion is required about the best way to do that, as well as more testing than is practical for an undisclosed security problem. Besides, the same issue probably affects some user-written test harnesses. So for the moment, we'll just warn people against using "make check" when there are untrusted users on the same machine. In passing, remove some ancient advice that suggested making the regression testing subtree world-writable if you'd built as root. That looks dangerously insecure in modern contexts, and anyway we should not be encouraging people to build Postgres as root. Security: CVE-2014-0067
* Prevent potential overruns of fixed-size buffers.Tom Lane2014-02-17
| | | | | | | | | | | | | | | | | | | | | | | Coverity identified a number of places in which it couldn't prove that a string being copied into a fixed-size buffer would fit. We believe that most, perhaps all of these are in fact safe, or are copying data that is coming from a trusted source so that any overrun is not really a security issue. Nonetheless it seems prudent to forestall any risk by using strlcpy() and similar functions. Fixes by Peter Eisentraut and Jozef Mlich based on Coverity reports. In addition, fix a potential null-pointer-dereference crash in contrib/chkpass. The crypt(3) function is defined to return NULL on failure, but chkpass.c didn't check for that before using the result. The main practical case in which this could be an issue is if libc is configured to refuse to execute unapproved hashing algorithms (e.g., "FIPS mode"). This ideally should've been a separate commit, but since it touches code adjacent to one of the buffer overrun changes, I included it in this commit to avoid last-minute merge issues. This issue was reported by Honza Horak. Security: CVE-2014-0065 for buffer overruns, CVE-2014-0066 for crypt()
* Predict integer overflow to avoid buffer overruns.Noah Misch2014-02-17
| | | | | | | | | | | | | | | | | Several functions, mostly type input functions, calculated an allocation size such that the calculation wrapped to a small positive value when arguments implied a sufficiently-large requirement. Writes past the end of the inadvertent small allocation followed shortly thereafter. Coverity identified the path_in() vulnerability; code inspection led to the rest. In passing, add check_stack_depth() to prevent stack overflow in related functions. Back-patch to 8.4 (all supported versions). The non-comment hstore changes touch code that did not exist in 8.4, so that part stops at 9.0. Noah Misch and Heikki Linnakangas, reviewed by Tom Lane. Security: CVE-2014-0064
* Fix handling of wide datetime input/output.Noah Misch2014-02-17
| | | | | | | | | | | | | | | | | Many server functions use the MAXDATELEN constant to size a buffer for parsing or displaying a datetime value. It was much too small for the longest possible interval output and slightly too small for certain valid timestamp input, particularly input with a long timezone name. The long input was rejected needlessly; the long output caused interval_out() to overrun its buffer. ECPG's pgtypes library has a copy of the vulnerable functions, which bore the same vulnerabilities along with some of its own. In contrast to the server, certain long inputs caused stack overflow rather than failing cleanly. Back-patch to 8.4 (all supported versions). Reported by Daniel Schüssler, reviewed by Tom Lane. Security: CVE-2014-0063
* Avoid repeated name lookups during table and index DDL.Robert Haas2014-02-17
| | | | | | | | | | | | | | | | | | | | | | If the name lookups come to different conclusions due to concurrent activity, we might perform some parts of the DDL on a different table than other parts. At least in the case of CREATE INDEX, this can be used to cause the permissions checks to be performed against a different table than the index creation, allowing for a privilege escalation attack. This changes the calling convention for DefineIndex, CreateTrigger, transformIndexStmt, transformAlterTableStmt, CheckIndexCompatible (in 9.2 and newer), and AlterTable (in 9.1 and older). In addition, CheckRelationOwnership is removed in 9.2 and newer and the calling convention is changed in older branches. A field has also been added to the Constraint node (FkConstraint in 8.4). Third-party code calling these functions or using the Constraint node will require updating. Report by Andres Freund. Patch by Robert Haas and Andres Freund, reviewed by Tom Lane. Security: CVE-2014-0062
* Document security implications of check_function_bodies.Noah Misch2014-02-17
| | | | Back-patch to 8.4 (all supported versions).
* Prevent privilege escalation in explicit calls to PL validators.Noah Misch2014-02-17
| | | | | | | | | | | | | | The primary role of PL validators is to be called implicitly during CREATE FUNCTION, but they are also normal functions that a user can call explicitly. Add a permissions check to each validator to ensure that a user cannot use explicit validator calls to achieve things he could not otherwise achieve. Back-patch to 8.4 (all supported versions). Non-core procedural language extensions ought to make the same two-line change to their own validators. Andres Freund, reviewed by Tom Lane and Noah Misch. Security: CVE-2014-0061
* Shore up ADMIN OPTION restrictions.Noah Misch2014-02-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Granting a role without ADMIN OPTION is supposed to prevent the grantee from adding or removing members from the granted role. Issuing SET ROLE before the GRANT bypassed that, because the role itself had an implicit right to add or remove members. Plug that hole by recognizing that implicit right only when the session user matches the current role. Additionally, do not recognize it during a security-restricted operation or during execution of a SECURITY DEFINER function. The restriction on SECURITY DEFINER is not security-critical. However, it seems best for a user testing his own SECURITY DEFINER function to see the same behavior others will see. Back-patch to 8.4 (all supported versions). The SQL standards do not conflate roles and users as PostgreSQL does; only SQL roles have members, and only SQL users initiate sessions. An application using PostgreSQL users and roles as SQL users and roles will never attempt to grant membership in the role that is the session user, so the implicit right to add or remove members will never arise. The security impact was mostly that a role member could revoke access from others, contrary to the wishes of his own grantor. Unapproved role member additions are less notable, because the member can still largely achieve that by creating a view or a SECURITY DEFINER function. Reviewed by Andres Freund and Tom Lane. Reported, independently, by Jonas Sundman and Noah Misch. Security: CVE-2014-0060
* Release notes for 9.3.3, 9.2.7, 9.1.12, 9.0.16, 8.4.20.Tom Lane2014-02-16
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* Ooops, forgot to remove solar87 and friends from src/timezone/Makefile.Tom Lane2014-02-14
| | | | Per buildfarm.
* Update time zone data files to tzdata release 2013i.Tom Lane2014-02-14
| | | | | | | | | | | | DST law changes in Jordan; historical changes in Cuba. Also, remove the zones Asia/Riyadh87, Asia/Riyadh88, and Asia/Riyadh89. Per the upstream announcement: The files solar87, solar88, and solar89 are no longer distributed. They were a negative experiment -- that is, a demonstration that tz data can represent solar time only with some difficulty and error. Their presence in the distribution caused confusion, as Riyadh civil time was generally not solar time in those years.
* Update regression testing instructions.Tom Lane2014-02-14
| | | | | | | | | | | | | This documentation never got the word about the existence of check-world or installcheck-world. Revise to recommend use of those, and document all the subsidiary test suites. Do some minor wordsmithing elsewhere, too. In passing, remove markup related to generation of plain-text regression test instructions, since we don't do that anymore. Back-patch to 9.1 where check-world was added. (installcheck-world exists in 9.0; but since check-world doesn't, this patch would need additional work to cover that branch, and it doesn't seem worth the effort.)
* Suggest shell here-documents instead of psql -c for multiple commands.Tom Lane2014-02-14
| | | | | | The documentation suggested using "echo | psql", but not the often-superior alternative of a here-document. Also, be more direct about suggesting that people avoid -c for multiple commands. Per discussion.
* Clean up error cases in psql's COPY TO STDOUT/FROM STDIN code.Tom Lane2014-02-13
| | | | | | | | | | | | | | | | | | | | | | | Adjust handleCopyOut() to stop trying to write data once it's failed one time. For typical cases such as out-of-disk-space or broken-pipe, additional attempts aren't going to do anything but waste time, and in any case clean truncation of the output seems like a better behavior than randomly dropping blocks in the middle. Also remove dubious (and misleadingly documented) attempt to force our way out of COPY_OUT state if libpq didn't do that. If we did have a situation like that, it'd be a bug in libpq and would be better fixed there, IMO. We can hope that commit fa4440f51628d692f077d54b8313aea31af087ea took care of any such problems, anyway. Also fix longstanding bug in handleCopyIn(): PQputCopyEnd() only supports a non-null errormsg parameter in protocol version 3, and will actively fail if one is passed in version 2. This would've made our attempts to get out of COPY_IN state after a failure into infinite loops when talking to pre-7.4 servers. Back-patch the COPY_OUT state change business back to 9.2 where it was introduced, and the other two fixes into all supported branches.
* Fix length checking for Unicode identifiers containing escapes (U&"...").Tom Lane2014-02-13
| | | | | | | | | | | We used the length of the input string, not the de-escaped string, as the trigger for NAMEDATALEN truncation. AFAICS this would only result in sometimes printing a phony truncation warning; but it's just luck that there was no worse problem, since we were violating the API spec for truncate_identifier(). Per bug #9204 from Joshua Yanovski. This has been wrong since the Unicode-identifier support was added, so back-patch to all supported branches.
* Improve cross-references between minor version release notes.Tom Lane2014-02-12
| | | | | | | | | | | | We have a practice of providing a "bread crumb" trail between the minor versions where the migration section actually tells you to do something. Historically that was just plain text, eg, "see the release notes for 9.2.4"; but if you're using a browser or PDF reader, it's a lot nicer if it's a live hyperlink. So use "<xref>" instead. Any argument against doing this vanished with the recent decommissioning of plain-text release notes. Vik Fearing
* Improve text of stub HISTORY file.Tom Lane2014-02-12
| | | | Per Peter Eisentraut.
* Improve libpq's error recovery for connection loss during COPY.Tom Lane2014-02-12
| | | | | | | | | | | | | | | | | | | | | | | | In pqSendSome, if the connection is already closed at entry, discard any queued output data before returning. There is no possibility of ever sending the data, and anyway this corresponds to what we'd do if we'd detected a hard error while trying to send(). This avoids possible indefinite bloat of the output buffer if the application keeps trying to send data (or even just keeps trying to do PQputCopyEnd, as psql indeed will). Because PQputCopyEnd won't transition out of PGASYNC_COPY_IN state until it's successfully queued the COPY END message, and pqPutMsgEnd doesn't distinguish a queuing failure from a pqSendSome failure, this omission allowed an infinite loop in psql if the connection closure occurred when we had at least 8K queued to send. It might be worth refactoring so that we can make that distinction, but for the moment the other changes made here seem to offer adequate defenses. To guard against other variants of this scenario, do not allow PQgetResult to return a PGRES_COPY_XXX result if the connection is already known dead. Make sure it returns PGRES_FATAL_ERROR instead. Per report from Stephen Frost. Back-patch to all active branches.