PostgreSQL 9.2.15 commit log

Stamp 9.2.15.

  
commit   : a0606058016b7d20406910b7a73e60ddb3e4c9ff    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 8 Feb 2016 16:19:37 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 8 Feb 2016 16:19:37 -0500    

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Translation updates

  
commit   : 6a10dd08006e8f0ce9c1dc2f45379bb17f428e27    
  
author   : Peter Eisentraut <peter_e@gmx.net>    
date     : Mon, 8 Feb 2016 14:42:59 -0500    
  
committer: Peter Eisentraut <peter_e@gmx.net>    
date     : Mon, 8 Feb 2016 14:42:59 -0500    

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Source-Git-URL: git://git.postgresql.org/git/pgtranslation/messages.git  
Source-Git-Hash: e640b67db0ef2d766eb6b5ec60dc3ba5ed4e2ede  
  

Last-minute updates for release notes.

  
commit   : 9dafc4130d948e9f0a1313e3708b79dee143c423    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 8 Feb 2016 10:49:38 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 8 Feb 2016 10:49:38 -0500    

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Security: CVE-2016-0773  
  

Fix some regex issues with out-of-range characters and large char ranges.

  
commit   : e93516cf7fa10ffaad1fa1f096d88fce21cc7c56    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 8 Feb 2016 10:25:40 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 8 Feb 2016 10:25:40 -0500    

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Previously, our regex code defined CHR_MAX as 0xfffffffe, which is a  
bad choice because it is outside the range of type "celt" (int32).  
Characters approaching that limit could lead to infinite loops in logic  
such as "for (c = a; c <= b; c++)" where c is of type celt but the  
range bounds are chr.  Such loops will work safely only if CHR_MAX+1  
is representable in celt, since c must advance to beyond b before the  
loop will exit.  
  
Fortunately, there seems no reason not to restrict CHR_MAX to 0x7ffffffe.  
It's highly unlikely that Unicode will ever assign codes that high, and  
none of our other backend encodings need characters beyond that either.  
  
In addition to modifying the macro, we have to explicitly enforce character  
range restrictions on the values of \u, \U, and \x escape sequences, else  
the limit is trivially bypassed.  
  
Also, the code for expanding case-independent character ranges in bracket  
expressions had a potential integer overflow in its calculation of the  
number of characters it could generate, which could lead to allocating too  
small a character vector and then overwriting memory.  An attacker with the  
ability to supply arbitrary regex patterns could easily cause transient DOS  
via server crashes, and the possibility for privilege escalation has not  
been ruled out.  
  
Quite aside from the integer-overflow problem, the range expansion code was  
unnecessarily inefficient in that it always produced a result consisting of  
individual characters, abandoning the knowledge that we had a range to  
start with.  If the input range is large, this requires excessive memory.  
Change it so that the original range is reported as-is, and then we add on  
any case-equivalent characters that are outside that range.  With this  
approach, we can bound the number of individual characters allowed without  
sacrificing much.  This patch allows at most 100000 individual characters,  
which I believe to be more than the number of case pairs existing in  
Unicode, so that the restriction will never be hit in practice.  
  
It's still possible for range() to take awhile given a large character code  
range, so also add statement-cancel detection to its loop.  The downstream  
function dovec() also lacked cancel detection, and could take a long time  
given a large output from range().  
  
Per fuzz testing by Greg Stark.  Back-patch to all supported branches.  
  
Security: CVE-2016-0773  
  

Improve documentation about PRIMARY KEY constraints.

  
commit   : ddcc256caf5523d5b856b2f461178f2711bcd345    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 7 Feb 2016 16:02:44 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 7 Feb 2016 16:02:44 -0500    

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Get rid of the false implication that PRIMARY KEY is exactly equivalent to  
UNIQUE + NOT NULL.  That was more-or-less true at one time in our  
implementation, but the standard doesn't say that, and we've grown various  
features (many of them required by spec) that treat a pkey differently from  
less-formal constraints.  Per recent discussion on pgsql-general.  
  
I failed to resist the temptation to do some other wordsmithing in the  
same area.  
  

Release notes for 9.5.1, 9.4.6, 9.3.11, 9.2.15, 9.1.20.

  
commit   : 3d6c9888900a31553720b241f2beb7ca2cd826d2    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 7 Feb 2016 14:16:32 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 7 Feb 2016 14:16:32 -0500    

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Force certain “pljava” custom GUCs to be PGC_SUSET.

  
commit   : de9766d39d91f0069fc95bfaac0caed8546f8ccc    
  
author   : Noah Misch <noah@leadboat.com>    
date     : Fri, 5 Feb 2016 20:22:51 -0500    
  
committer: Noah Misch <noah@leadboat.com>    
date     : Fri, 5 Feb 2016 20:22:51 -0500    

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Future PL/Java versions will close CVE-2016-0766 by making these GUCs  
PGC_SUSET.  This PostgreSQL change independently mitigates that PL/Java  
vulnerability, helping sites that update PostgreSQL more frequently than  
PL/Java.  Back-patch to 9.1 (all supported versions).  
  

Update time zone data files to tzdata release 2016a.

  
commit   : 32f17a2e7d16904b94dcbebb06f5001dd092c4dc    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 5 Feb 2016 10:59:09 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 5 Feb 2016 10:59:09 -0500    

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DST law changes in Cayman Islands, Metlakatla, Trans-Baikal Territory  
(Zabaykalsky Krai).  Historical corrections for Pakistan.  
  

In pg_dump, ensure that view triggers are processed after view rules.

  
commit   : 4f58a70039f68ecf46635636ad4929c3019a245e    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 4 Feb 2016 00:26:10 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 4 Feb 2016 00:26:10 -0500    

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If a view is split into CREATE TABLE + CREATE RULE to break a circular  
dependency, then any triggers on the view must be dumped/reloaded after  
the CREATE RULE; else the backend may reject the CREATE TRIGGER because  
it's the wrong type of trigger for a plain table.  This works all right  
in plain dump/restore because of pg_dump's sorting heuristic that places  
triggers after rules.  However, when using parallel restore, the ordering  
must be enforced by a dependency --- and we didn't have one.  
  
Fixing this is a mere matter of adding an addObjectDependency() call,  
except that we need to be able to find all the triggers belonging to the  
view relation, and there was no easy way to do that.  Add fields to  
pg_dump's TableInfo struct to remember where the associated TriggerInfo  
struct(s) are.  
  
Per bug report from Dennis Kögel.  The failure can be exhibited at least  
as far back as 9.1, so back-patch to all supported branches.  
  

pgbench: Install guard against overflow when dividing by -1.

  
commit   : b63a4f418f5611272f28d0633932ffbf3bbd3015    
  
author   : Robert Haas <rhaas@postgresql.org>    
date     : Wed, 3 Feb 2016 09:15:29 -0500    
  
committer: Robert Haas <rhaas@postgresql.org>    
date     : Wed, 3 Feb 2016 09:15:29 -0500    

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Commit 64f5edca2401f6c2f23564da9dd52e92d08b3a20 fixed the same hazard  
on master; this is a backport, but the modulo operator does not exist  
in older releases.  
  
Michael Paquier  
  

Make sure ecpg header files do not have a comment lasting several lines, one of which is a preprocessor directive. This leads ecpg to incorrectly parse the comment as nested.

  
commit   : d9ce5d201d17e360b8de2cd3d912c1fec49d85fd    
  
author   : Michael Meskes <meskes@postgresql.org>    
date     : Mon, 1 Feb 2016 13:10:40 +0100    
  
committer: Michael Meskes <meskes@postgresql.org>    
date     : Mon, 1 Feb 2016 13:10:40 +0100    

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Fix error in documentated use of mingw-w64 compilers

  
commit   : 555bc8b374f0883b51b937749e39ef8569bfd0d8    
  
author   : Andrew Dunstan <andrew@dunslane.net>    
date     : Sat, 30 Jan 2016 19:28:44 -0500    
  
committer: Andrew Dunstan <andrew@dunslane.net>    
date     : Sat, 30 Jan 2016 19:28:44 -0500    

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Error reported by Igal Sapir.  
  

Fix incorrect pattern-match processing in psql’s \det command.

  
commit   : a362cc2e3528c183de72863d2779912b0323ee4b    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 29 Jan 2016 10:28:03 +0100    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 29 Jan 2016 10:28:03 +0100    

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listForeignTables' invocation of processSQLNamePattern did not match up  
with the other ones that handle potentially-schema-qualified names; it  
failed to make use of pg_table_is_visible() and also passed the name  
arguments in the wrong order.  Bug seems to have been aboriginal in commit  
0d692a0dc9f0e532.  It accidentally sort of worked as long as you didn't  
inquire too closely into the behavior, although the silliness was later  
exposed by inconsistencies in the test queries added by 59efda3e50ca4de6  
(which I probably should have questioned at the time, but didn't).  
  
Per bug #13899 from Reece Hart.  Patch by Reece Hart and Tom Lane.  
Back-patch to all affected branches.  
  

Fix startup so that log prefix %h works for the log_connections message.

  
commit   : 3a7af9d73b8f48d49837633ae07cf8c15b48ddd9    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 26 Jan 2016 15:38:33 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 26 Jan 2016 15:38:33 -0500    

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We entirely randomly chose to initialize port->remote_host just after  
printing the log_connections message, when we could perfectly well do it  
just before, allowing %h and %r to work for that message.  Per gripe from  
Artem Tomyuk.  
  

Properly install dynloader.h on MSVC builds

  
commit   : 49d65e857cad7ddc4d82f8276cc63ddce0be4ee1    
  
author   : Bruce Momjian <bruce@momjian.us>    
date     : Tue, 19 Jan 2016 23:30:28 -0500    
  
committer: Bruce Momjian <bruce@momjian.us>    
date     : Tue, 19 Jan 2016 23:30:28 -0500    

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This will enable PL/Java to be cleanly compiled, as dynloader.h is a  
requirement.  
  
Report by Chapman Flack  
  
Patch by Michael Paquier  
  
Backpatch through 9.1  
  

Fix spelling mistake.

  
commit   : f744f395a5cab388b597ef9f80a349a6fbe8157f    
  
author   : Robert Haas <rhaas@postgresql.org>    
date     : Thu, 14 Jan 2016 23:12:05 -0500    
  
committer: Robert Haas <rhaas@postgresql.org>    
date     : Thu, 14 Jan 2016 23:12:05 -0500    

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Same patch submitted independently by David Rowley and Peter Geoghegan.  
  

Properly close token in sspi authentication

  
commit   : df0bd5a0f7e8893e1177f53b1ca126ffaf24160e    
  
author   : Magnus Hagander <magnus@hagander.net>    
date     : Thu, 14 Jan 2016 13:06:03 +0100    
  
committer: Magnus Hagander <magnus@hagander.net>    
date     : Thu, 14 Jan 2016 13:06:03 +0100    

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We can never leak more than one token, but we shouldn't do that. We  
don't bother closing it in the error paths since the process will  
exit shortly anyway.  
  
Christian Ullrich  
  

Handle extension members when first setting object dump flags in pg_dump.

  
commit   : be2b27651422a7d5426d29e5bf7d9a319afc1a77    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 13 Jan 2016 18:55:27 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 13 Jan 2016 18:55:27 -0500    

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pg_dump's original approach to handling extension member objects was to  
run around and clear (or set) their dump flags rather late in its data  
collection process.  Unfortunately, quite a lot of code expects those flags  
to be valid before that; which was an entirely reasonable expectation  
before we added extensions.  In particular, this explains Karsten Hilbert's  
recent report of pg_upgrade failing on a database in which an extension  
has been installed into the pg_catalog schema.  Its objects are initially  
marked as not-to-be-dumped on the strength of their schema, and later we  
change them to must-dump because we're doing a binary upgrade of their  
extension; but we've already skipped essential tasks like making associated  
DO_SHELL_TYPE objects.  
  
To fix, collect extension membership data first, and incorporate it in the  
initial setting of the dump flags, so that those are once again correct  
from the get-go.  This has the undesirable side effect of slightly  
lengthening the time taken before pg_dump acquires table locks, but testing  
suggests that the increase in that window is not very much.  
  
Along the way, get rid of ugly special-case logic for deciding whether  
to dump procedural languages, FDWs, and foreign servers; dump decisions  
for those are now correct up-front, too.  
  
In 9.3 and up, this also fixes erroneous logic about when to dump event  
triggers (basically, they were *always* dumped before).  In 9.5 and up,  
transform objects had that problem too.  
  
Since this problem came in with extensions, back-patch to all supported  
versions.  
  

Avoid dump/reload problems when using both plpython2 and plpython3.

  
commit   : 3843ba510bb1586ba8bc29ecf8df7d4fb60d02bb    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 11 Jan 2016 19:55:40 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 11 Jan 2016 19:55:40 -0500    

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Commit 803716013dc1350f installed a safeguard against loading plpython2  
and plpython3 at the same time, but asserted that both could still be  
used in the same database, just not in the same session.  However, that's  
not actually all that practical because dumping and reloading will fail  
(since both libraries necessarily get loaded into the restoring session).  
pg_upgrade is even worse, because it checks for missing libraries by  
loading every .so library mentioned in the entire installation into one  
session, so that you can have only one across the whole cluster.  
  
We can improve matters by not throwing the error immediately in _PG_init,  
but only when and if we're asked to do something that requires calling  
into libpython.  This ameliorates both of the above situations, since  
while execution of CREATE LANGUAGE, CREATE FUNCTION, etc will result in  
loading plpython, it isn't asked to do anything interesting (at least  
not if check_function_bodies is off, as it will be during a restore).  
  
It's possible that this opens some corner-case holes in which a crash  
could be provoked with sufficient effort.  However, since plpython  
only exists as an untrusted language, any such crash would require  
superuser privileges, making it "don't do that" not a security issue.  
To reduce the hazards in this area, the error is still FATAL when it  
does get thrown.  
  
Per a report from Paul Jones.  Back-patch to 9.2, which is as far back  
as the patch applies without work.  (It could be made to work in 9.1,  
but given the lack of previous complaints, I'm disinclined to expend  
effort so far back.  We've been pretty desultory about support for  
Python 3 in 9.1 anyway.)  
  

Clean up some lack-of-STRICT issues in the core code, too.

  
commit   : 0e7d084aedea99f8dbd153959f3e3b5e81c25c61    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 9 Jan 2016 16:58:33 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 9 Jan 2016 16:58:33 -0500    

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A scan for missed proisstrict markings in the core code turned up  
these functions:  
  
brin_summarize_new_values  
pg_stat_reset_single_table_counters  
pg_stat_reset_single_function_counters  
pg_create_logical_replication_slot  
pg_create_physical_replication_slot  
pg_drop_replication_slot  
  
The first three of these take OID, so a null argument will normally look  
like a zero to them, resulting in "ERROR: could not open relation with OID  
0" for brin_summarize_new_values, and no action for the pg_stat_reset_XXX  
functions.  The other three will dump core on a null argument, though this  
is mitigated by the fact that they won't do so until after checking that  
the caller is superuser or has rolreplication privilege.  
  
In addition, the pg_logical_slot_get/peek[_binary]_changes family was  
intentionally marked nonstrict, but failed to make nullness checks on all  
the arguments; so again a null-pointer-dereference crash is possible but  
only for superusers and rolreplication users.  
  
Add the missing ARGISNULL checks to the latter functions, and mark the  
former functions as strict in pg_proc.  Make that change in the back  
branches too, even though we can't force initdb there, just so that  
installations initdb'd in future won't have the issue.  Since none of these  
bugs rise to the level of security issues (and indeed the pg_stat_reset_XXX  
functions hardly misbehave at all), it seems sufficient to do this.  
  
In addition, fix some order-of-operations oddities in the slot_get_changes  
family, mostly cosmetic, but not the part that moves the function's last  
few operations into the PG_TRY block.  As it stood, there was significant  
risk for an error to exit without clearing historical information from  
the system caches.  
  
The slot_get_changes bugs go back to 9.4 where that code was introduced.  
Back-patch appropriate subsets of the pg_proc changes into all active  
branches, as well.  
  

Clean up code for widget_in() and widget_out().

  
commit   : 1eb2c4bfd17b368939371757aff294055078ef13    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 9 Jan 2016 13:44:27 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 9 Jan 2016 13:44:27 -0500    

Click here for diff

  
Given syntactically wrong input, widget_in() could call atof() with an  
indeterminate pointer argument, typically leading to a crash; or if it  
didn't do that, it might return a NULL pointer, which again would lead  
to a crash since old-style C functions aren't supposed to do things  
that way.  Fix that by correcting the off-by-one syntax test and  
throwing a proper error rather than just returning NULL.  
  
Also, since widget_in and widget_out have been marked STRICT for a  
long time, their tests for null inputs are just dead code; remove 'em.  
In the oldest branches, also improve widget_out to use snprintf not  
sprintf, just to be sure.  
  
In passing, get rid of a long-since-useless sprintf into a local buffer  
that nothing further is done with, and make some other minor coding  
style cleanups.  
  
In the intended regression-testing usage of these functions, none of  
this is very significant; but if the regression test database were  
left around in a production installation, these bugs could amount  
to a minor security hazard.  
  
Piotr Stefaniak, Michael Paquier, and Tom Lane  
  

Add STRICT to some C functions created by the regression tests.

  
commit   : 55caeeee0f5b0310fc99f47b4abfdd6d987871e6    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 9 Jan 2016 13:02:54 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 9 Jan 2016 13:02:54 -0500    

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These functions readily crash when passed a NULL input value.  The tests  
themselves do not pass NULL values to them; but when the regression  
database is used as a basis for fuzz testing, they cause a lot of noise.  
Also, if someone were to leave a regression database lying about in a  
production installation, these would create a minor security hazard.  
  
Andreas Seltenreich  
  

Fix unobvious interaction between -X switch and subdirectory creation.

  
commit   : 957e1117da128c9615e81823db2ce0bc81f8cf81    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 7 Jan 2016 18:20:58 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 7 Jan 2016 18:20:58 -0500    

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Turns out the only reason initdb -X worked is that pg_mkdir_p won't  
whine if you point it at something that's a symlink to a directory.  
Otherwise, the attempt to create pg_xlog/ just like all the other  
subdirectories would have failed.  Let's be a little more explicit  
about what's happening.  Oversight in my patch for bug #13853  
(mea culpa for not testing -X ...)  
  

Use plain mkdir() not pg_mkdir_p() to create subdirectories of PGDATA.

  
commit   : d6d6400cc0357c409262dc95d3001e70da8605c4    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 7 Jan 2016 15:22:01 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 7 Jan 2016 15:22:01 -0500    

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When we're creating subdirectories of PGDATA during initdb, we know darn  
well that the parent directory exists (or should exist) and that the new  
subdirectory doesn't (or shouldn't).  There is therefore no need to use  
anything more complicated than mkdir().  Using pg_mkdir_p() just opens us  
up to unexpected failure modes, such as the one exhibited in bug #13853  
from Nuri Boardman.  It's not very clear why pg_mkdir_p() went wrong there,  
but it is clear that we didn't need to be trying to create parent  
directories in the first place.  We're not even saving any code, as proven  
by the fact that this patch nets out at minus five lines.  
  
Since this is a response to a field bug report, back-patch to all branches.  
  

Windows: Make pg_ctl reliably detect service status

  
commit   : 5c4cbd5d103c681a8cad586bac3588029ae44590    
  
author   : Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Thu, 7 Jan 2016 11:59:08 -0300    
  
committer: Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Thu, 7 Jan 2016 11:59:08 -0300    

Click here for diff

  
pg_ctl is using isatty() to verify whether the process is running in a  
terminal, and if not it sends its output to Windows' Event Log ... which  
does the wrong thing when the output has been redirected to a pipe, as  
reported in bug #13592.  
  
To fix, make pg_ctl use the code we already have to detect service-ness:  
in the master branch, move src/backend/port/win32/security.c to src/port  
(with suitable tweaks so that it runs properly in backend and frontend  
environments); pg_ctl already has access to pgport so it Just Works.  In  
older branches, that's likely to cause trouble, so instead duplicate the  
required code in pg_ctl.c.  
  
Author: Michael Paquier  
Bug report and diagnosis: Egon Kocjan  
Backpatch: all supported branches  
  

Fix treatment of *lpNumberOfBytesRecvd == 0: that’s a completion condition.

  
commit   : 9b2eacba79916df5f3b436e226531e5891c633bc    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 4 Jan 2016 17:41:33 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 4 Jan 2016 17:41:33 -0500    

Click here for diff

  
pgwin32_recv() has treated a non-error return of zero bytes from WSARecv()  
as being a reason to block ever since the current implementation was  
introduced in commit a4c40f140d23cefb.  However, so far as one can tell  
from Microsoft's documentation, that is just wrong: what it means is  
graceful connection closure (in stream protocols) or receipt of a  
zero-length message (in message protocols), and neither case should result  
in blocking here.  The only reason the code worked at all was that control  
then fell into the retry loop, which did *not* treat zero bytes specially,  
so we'd get out after only wasting some cycles.  But as of 9.5 we do not  
normally reach the retry loop and so the bug is exposed, as reported by  
Shay Rojansky and diagnosed by Andres Freund.  
  
Remove the unnecessary test on the byte count, and rearrange the code  
in the retry loop so that it looks identical to the initial sequence.  
  
Back-patch of commit 90e61df8130dc7051a108ada1219fb0680cb3eb6.  The  
original plan was to apply this only to 9.5 and up, but after discussion  
and buildfarm testing, it seems better to back-patch.  The noblock code  
path has been at risk of this problem since it was introduced (in 9.0);  
if it did happen in pre-9.5 branches, the symptom would be that a walsender  
would wait indefinitely rather than noticing a loss of connection.  While  
we lack proof that the case has been seen in the field, it seems possible  
that it's happened without being reported.  
  

Teach pg_dump to quote reloption values safely.

  
commit   : 1eb515ad7c1295099b252a58d71183e53ce2f818    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 2 Jan 2016 19:04:45 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 2 Jan 2016 19:04:45 -0500    

Click here for diff

  
Commit c7e27becd2e6eb93 fixed this on the backend side, but we neglected  
the fact that several code paths in pg_dump were printing reloptions  
values that had not gotten massaged by ruleutils.  Apply essentially the  
same quoting logic in those places, too.  
  

Fix overly-strict assertions in spgtextproc.c.

  
commit   : 5c0d6230f54c97c3fa5cf9a7cc286c35ebaad766    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 2 Jan 2016 16:24:50 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 2 Jan 2016 16:24:50 -0500    

Click here for diff

  
spg_text_inner_consistent is capable of reconstructing an empty string  
to pass down to the next index level; this happens if we have an empty  
string coming in, no prefix, and a dummy node label.  (In practice, what  
is needed to trigger that is insertion of a whole bunch of empty-string  
values.)  Then, we will arrive at the next level with in->level == 0  
and a non-NULL (but zero length) in->reconstructedValue, which is valid  
but the Assert tests weren't expecting it.  
  
Per report from Andreas Seltenreich.  This has no impact in non-Assert  
builds, so should not be a problem in production, but back-patch to  
all affected branches anyway.  
  
In passing, remove a couple of useless variable initializations and  
shorten the code by not duplicating DatumGetPointer() calls.  
  

Adjust back-branch release note description of commits a2a718b22 et al.

  
commit   : c6ab17829284abb68d29ab75400eef9957a4f36f    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 2 Jan 2016 15:29:03 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 2 Jan 2016 15:29:03 -0500    

Click here for diff

  
As pointed out by Michael Paquier, recovery_min_apply_delay didn't exist  
in 9.0-9.3, making the release note text not very useful.  Instead make it  
talk about recovery_target_xid, which did exist then.  
  
9.0 is already out of support, but we can fix the text in the newer  
branches' copies of its release notes.  
  

  
commit   : 25b04756ea72260c744e87621f815aa5a3b11724    
  
author   : Bruce Momjian <bruce@momjian.us>    
date     : Sat, 2 Jan 2016 13:33:39 -0500    
  
committer: Bruce Momjian <bruce@momjian.us>    
date     : Sat, 2 Jan 2016 13:33:39 -0500    

Click here for diff

  
Backpatch certain files through 9.1  
  

Teach flatten_reloptions() to quote option values safely.

  
commit   : 69cfe15b57f782b2aa108a1a7b893bd4803007b3    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 1 Jan 2016 15:27:53 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 1 Jan 2016 15:27:53 -0500    

Click here for diff

  
flatten_reloptions() supposed that it didn't really need to do anything  
beyond inserting commas between reloption array elements.  However, in  
principle the value of a reloption could be nearly anything, since the  
grammar allows a quoted string there.  Any restrictions on it would come  
from validity checking appropriate to the particular option, if any.  
  
A reloption value that isn't a simple identifier or number could thus lead  
to dump/reload failures due to syntax errors in CREATE statements issued  
by pg_dump.  We've gotten away with not worrying about this so far with  
the core-supported reloptions, but extensions might allow reloption values  
that cause trouble, as in bug #13840 from Kouhei Sutou.  
  
To fix, split the reloption array elements explicitly, and then convert  
any value that doesn't look like a safe identifier to a string literal.  
(The details of the quoting rule could be debated, but this way is safe  
and requires little code.)  While we're at it, also quote reloption names  
if they're not safe identifiers; that may not be a likely problem in the  
field, but we might as well try to be bulletproof here.  
  
It's been like this for a long time, so back-patch to all supported  
branches.  
  
Kouhei Sutou, adjusted some by me  
  

Add some more defenses against silly estimates to gincostestimate().

  
commit   : 8e79b24c5d3dc47919e5b0b0a08943f7ca420998    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 1 Jan 2016 13:42:21 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 1 Jan 2016 13:42:21 -0500    

Click here for diff

  
A report from Andy Colson showed that gincostestimate() was not being  
nearly paranoid enough about whether to believe the statistics it finds in  
the index metapage.  The problem is that the metapage stats (other than the  
pending-pages count) are only updated by VACUUM, and in the worst case  
could still reflect the index's original empty state even when it has grown  
to many entries.  We attempted to deal with that by scaling up the stats to  
match the current index size, but if nEntries is zero then scaling it up  
still gives zero.  Moreover, the proportion of pages that are entry pages  
vs. data pages vs. pending pages is unlikely to be estimated very well by  
scaling if the index is now orders of magnitude larger than before.  
  
We can improve matters by expanding the use of the rule-of-thumb estimates  
I introduced in commit 7fb008c5ee59b040: if the index has grown by more  
than a cutoff amount (here set at 4X growth) since VACUUM, then use the  
rule-of-thumb numbers instead of scaling.  This might not be exactly right  
but it seems much less likely to produce insane estimates.  
  
I also improved both the scaling estimate and the rule-of-thumb estimate  
to account for numPendingPages, since it's reasonable to expect that that  
is accurate in any case, and certainly pages that are in the pending list  
are not either entry or data pages.  
  
As a somewhat separate issue, adjust the estimation equations that are  
concerned with extra fetches for partial-match searches.  These equations  
suppose that a fraction partialEntries / numEntries of the entry and data  
pages will be visited as a consequence of a partial-match search.  Now,  
it's physically impossible for that fraction to exceed one, but our  
estimate of partialEntries is mostly bunk, and our estimate of numEntries  
isn't exactly gospel either, so we could arrive at a silly value.  In the  
example presented by Andy we were coming out with a value of 100, leading  
to insane cost estimates.  Clamp the fraction to one to avoid that.  
  
Like the previous patch, back-patch to all supported branches; this  
problem can be demonstrated in one form or another in all of them.  
  

Document the exponentiation operator as associating left to right.

  
commit   : 7adbde26ab638e0ce1154338d9b6e7801261d0d8    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 28 Dec 2015 12:09:00 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 28 Dec 2015 12:09:00 -0500    

Click here for diff

  
Common mathematical convention is that exponentiation associates right to  
left.  We aren't going to change the parser for this, but we could note  
it in the operator's description.  (It's already noted in the operator  
precedence/associativity table, but users might not look there.)  
Per bug #13829 from Henrik Pauli.  
  

Fix translation domain in pg_basebackup

  
commit   : 4fb9e6109a40a084eef102f4b6a827a01d69dbb8    
  
author   : Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 28 Dec 2015 10:50:35 -0300    
  
committer: Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 28 Dec 2015 10:50:35 -0300    

Click here for diff

  
For some reason, we've been overlooking the fact that pg_receivexlog  
and pg_recvlogical are using wrong translation domains all along,  
so their output hasn't ever been translated.  The right domain is  
pg_basebackup, not their own executable names.  
  
Noticed by Ioseph Kim, who's been working on the Korean translation.  
  
Backpatch pg_receivexlog to 9.2 and pg_recvlogical to 9.4.  
  

Add forgotten CHECK_FOR_INTERRUPT calls in pgcrypto’s crypt()

  
commit   : 51dd54ba79cc4b42a77c5246853a5794f44e1818    
  
author   : Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Sun, 27 Dec 2015 13:03:19 -0300    
  
committer: Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Sun, 27 Dec 2015 13:03:19 -0300    

Click here for diff

  
Both Blowfish and DES implementations of crypt() can take arbitrarily  
long time, depending on the number of rounds specified by the caller;  
make sure they can be interrupted.  
  
Author: Andreas Karlsson  
Reviewer: Jeff Janes  
  
Backpatch to 9.1.  
  

Rework internals of changing a type’s ownership

  
commit   : f9643d0d6dd303a6733f8b3015c7659680e7fe42    
  
author   : Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 21 Dec 2015 19:49:15 -0300    
  
committer: Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 21 Dec 2015 19:49:15 -0300    

Click here for diff

  
This is necessary so that REASSIGN OWNED does the right thing with  
composite types, to wit, that it also alters ownership of the type's  
pg_class entry -- previously, the pg_class entry remained owned by the  
original user, which caused later other failures such as the new owner's  
inability to use ALTER TYPE to rename an attribute of the affected  
composite.  Also, if the original owner is later dropped, the pg_class  
entry becomes owned by a non-existant user which is bogus.  
  
To fix, create a new routine AlterTypeOwner_oid which knows whether to  
pass the request to ATExecChangeOwner or deal with it directly, and use  
that in shdepReassignOwner rather than calling AlterTypeOwnerInternal  
directly.  AlterTypeOwnerInternal is now simpler in that it only  
modifies the pg_type entry and recurses to handle a possible array type;  
higher-level tasks are handled by either AlterTypeOwner directly or  
AlterTypeOwner_oid.  
  
I took the opportunity to add a few more objects to the test rig for  
REASSIGN OWNED, so that more cases are exercised.  Additional ones could  
be added for superuser-only-ownable objects (such as FDWs and event  
triggers) but I didn't want to push my luck by adding a new superuser to  
the tests on a backpatchable bug fix.  
  
Per bug #13666 reported by Chris Pacejo.  
  
This is a backpatch of commit 756e7b4c9db1 to branches 9.1 -- 9.4.  
  

some bullshit

  
commit   : 653530c8b1963bf91e19d03305dd0df5ad776bec    
  
author   : Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 21 Dec 2015 19:31:04 -0300    
  
committer: Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 21 Dec 2015 19:31:04 -0300    

Click here for diff

  
  

adjust ACL owners for REASSIGN and ALTER OWNER TO

  
commit   : 7af3dd540e29d057ff11d5c3ed946b071885c66f    
  
author   : Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 21 Dec 2015 19:16:15 -0300    
  
committer: Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 21 Dec 2015 19:16:15 -0300    

Click here for diff

  
When REASSIGN and ALTER OWNER TO are used, both the object owner and ACL  
list should be changed from the old owner to the new owner. This patch  
fixes types, foreign data wrappers, and foreign servers to change their  
ACL list properly;  they already changed owners properly.  
  
Report by Alexey Bashtanov  
  
This is a backpatch of commit 59367fdf97c (for bug #9923) by Bruce  
Momjian to branches 9.1 - 9.4; it wasn't backpatched originally out of  
concerns that it would create a backwards compatibility problem, but per  
discussion related to bug #13666 that turns out to have been misguided.  
(Therefore, the entry in the 9.5 release notes should be removed.)  
  
Note that 9.1 didn't have privileges on types (which were introduced by  
commit 729205571e81), so this commit only changes foreign-data related  
objects in that branch.  
  
Discussion: http://www.postgresql.org/message-id/20151216224004.GL2618@alvherre.pgsql  
	http://www.postgresql.org/message-id/10227.1450373793@sss.pgh.pa.us  
  

Remove silly completion for “DELETE FROM tabname …”.

  
commit   : 6ecd7f501062eb5e38240b9eb02e86aed248bd34    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 20 Dec 2015 18:29:51 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 20 Dec 2015 18:29:51 -0500    

Click here for diff

  
psql offered USING, WHERE, and SET in this context, but SET is not a valid  
possibility here.  Seems to have been a thinko in commit f5ab0a14ea83eb6c  
which added DELETE's USING option.  
  

Fix improper initialization order for readline.

  
commit   : b417779886f2d63f17f2049ce7ee7b290c470e15    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 17 Dec 2015 16:55:23 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 17 Dec 2015 16:55:23 -0500    

Click here for diff

  
Turns out we must set rl_basic_word_break_characters *before* we call  
rl_initialize() the first time, because it will quietly copy that value  
elsewhere --- but only on the first call.  (Love these undocumented  
dependencies.)  I broke this yesterday in commit 2ec477dc8108339d;  
like that commit, back-patch to all active branches.  Per report from  
Pavel Stehule.  
  

Cope with Readline’s failure to track SIGWINCH events outside of input.

  
commit   : bcce4a5e3ae0c93886989fb8ad615e5e6aa53a9f    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 16 Dec 2015 16:58:56 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 16 Dec 2015 16:58:56 -0500    

Click here for diff

  
It emerges that libreadline doesn't notice terminal window size change  
events unless they occur while collecting input.  This is easy to stumble  
over if you resize the window while using a pager to look at query output,  
but it can be demonstrated without any pager involvement.  The symptom is  
that queries exceeding one line are misdisplayed during subsequent input  
cycles, because libreadline has the wrong idea of the screen dimensions.  
  
The safest, simplest way to fix this is to call rl_reset_screen_size()  
just before calling readline().  That causes an extra ioctl(TIOCGWINSZ)  
for every command; but since it only happens when reading from a tty, the  
performance impact should be negligible.  A more valid objection is that  
this still leaves a tiny window during entry to readline() wherein delivery  
of SIGWINCH will be missed; but the practical consequences of that are  
probably negligible.  In any case, there doesn't seem to be any good way to  
avoid the race, since readline exposes no functions that seem safe to call  
from a generic signal handler --- rl_reset_screen_size() certainly isn't.  
  
It turns out that we also need an explicit rl_initialize() call, else  
rl_reset_screen_size() dumps core when called before the first readline()  
call.  
  
rl_reset_screen_size() is not present in old versions of libreadline,  
so we need a configure test for that.  (rl_initialize() is present at  
least back to readline 4.0, so we won't bother with a test for it.)  
We would need a configure test anyway since libedit's emulation of  
libreadline doesn't currently include such a function.  Fortunately,  
libedit seems not to have any corresponding bug.  
  
Merlin Moncure, adjusted a bit by me  
  

Add missing CHECK_FOR_INTERRUPTS in lseg_inside_poly

  
commit   : 48a7074a278656a786e082f13575ac223e1cdd56    
  
author   : Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 14 Dec 2015 16:44:40 -0300    
  
committer: Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Mon, 14 Dec 2015 16:44:40 -0300    

Click here for diff

  
Apparently, there are bugs in this code that cause it to loop endlessly.  
That bug still needs more research, but in the meantime it's clear that  
the loop is missing a check for interrupts so that it can be cancelled  
timely.  
  
Backpatch to 9.1 -- this has been missing since 49475aab8d0d.  
  

Fix out-of-memory error handling in ParameterDescription message processing.

  
commit   : 1e23caae30f5f7c841aa50eaa99b0145576e520b    
  
author   : Heikki Linnakangas <heikki.linnakangas@iki.fi>    
date     : Mon, 14 Dec 2015 18:19:10 +0200    
  
committer: Heikki Linnakangas <heikki.linnakangas@iki.fi>    
date     : Mon, 14 Dec 2015 18:19:10 +0200    

Click here for diff

  
If libpq ran out of memory while constructing the result set, it would hang,  
waiting for more data from the server, which might never arrive. To fix,  
distinguish between out-of-memory error and not-enough-data cases, and give  
a proper error message back to the client on OOM.  
  
There are still similar issues in handling COPY start messages, but let's  
handle that as a separate patch.  
  
Michael Paquier, Amit Kapila and me. Backpatch to all supported versions.  
  

Correct statement to actually be the intended assert statement.

  
commit   : ea3f30cf69f44ba7c37e0cccfb0aa74d82c98e54    
  
author   : Andres Freund <andres@anarazel.de>    
date     : Mon, 14 Dec 2015 11:24:55 +0100    
  
committer: Andres Freund <andres@anarazel.de>    
date     : Mon, 14 Dec 2015 11:24:55 +0100    

Click here for diff

  
e3f4cfc7 introduced a LWLockHeldByMe() call, without the corresponding  
Assert() surrounding it.  
  
Spotted by Coverity.  
  
Backpatch: 9.1+, like the previous commit  
  

Docs: document that psql’s “\i -” means read from stdin.

  
commit   : 6436445e9f311bc833d052c0fc39055fcbe09276    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 13 Dec 2015 23:42:54 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 13 Dec 2015 23:42:54 -0500    

Click here for diff

  
This has worked that way for a long time, maybe always, but you would  
not have known it from the documentation.  Also back-patch the notes  
I added to HEAD earlier today about behavior of the "-f -" switch,  
which likewise have been valid for many releases.  
  

Doc: update external URLs for PostGIS project.

  
commit   : 83497deb7d424952511aa933a954f36b487dd0cf    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 12 Dec 2015 20:02:09 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 12 Dec 2015 20:02:09 -0500    

Click here for diff

  
Paul Ramsey  
  

Fix ALTER TABLE … SET TABLESPACE for unlogged relations.

  
commit   : a15ad67089feed2e3f27613f0ead5243ca7ebbed    
  
author   : Andres Freund <andres@anarazel.de>    
date     : Sat, 12 Dec 2015 14:19:51 +0100    
  
committer: Andres Freund <andres@anarazel.de>    
date     : Sat, 12 Dec 2015 14:19:51 +0100    

Click here for diff

  
Changing the tablespace of an unlogged relation did not WAL log the  
creation and content of the init fork. Thus, after a standby is  
promoted, unlogged relation cannot be accessed anymore, with errors  
like:  
ERROR:  58P01: could not open file "pg_tblspc/...": No such file or directory  
Additionally the init fork was not synced to disk, independent of the  
configured wal_level, a relatively small durability risk.  
  
Investigation of that problem also brought to light that, even for  
permanent relations, the creation of !main forks was not WAL logged,  
i.e. no XLOG_SMGR_CREATE record were emitted. That mostly turns out not  
to be a problem, because these files were created when the actual  
relation data is copied; nonexistent files are not treated as an error  
condition during replay. But that doesn't work for empty files, and  
generally feels a bit haphazard. Luckily, outside init and main forks,  
empty forks don't occur often or are not a problem.  
  
Add the required WAL logging and syncing to disk.  
  
Reported-By: Michael Paquier  
Author: Michael Paquier and Andres Freund  
Discussion: 20151210163230.GA11331@alap3.anarazel.de  
Backpatch: 9.1, where unlogged relations were introduced  
  

Add an expected-file to match behavior of latest libxml2.

  
commit   : f5eebea8d8bffaa3fedb810634b8c8100b241f7a    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 11 Dec 2015 19:08:40 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 11 Dec 2015 19:08:40 -0500    

Click here for diff

  
Recent releases of libxml2 do not provide error context reports for errors  
detected at the very end of the input string.  This appears to be a bug, or  
at least an infelicity, introduced by the fix for libxml2's CVE-2015-7499.  
We can hope that this behavioral change will get undone before too long;  
but the security patch is likely to spread a lot faster/further than any  
follow-on cleanup, which means this behavior is likely to be present in the  
wild for some time to come.  As a stopgap, add a variant regression test  
expected-file that matches what you get with a libxml2 that acts this way.  
  

For REASSIGN OWNED for foreign user mappings

  
commit   : 629842a8eeab008f0a5487a267ddba26a66a6c29    
  
author   : Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Fri, 11 Dec 2015 18:39:09 -0300    
  
committer: Alvaro Herrera <alvherre@alvh.no-ip.org>    
date     : Fri, 11 Dec 2015 18:39:09 -0300    

Click here for diff

  
As reported in bug #13809 by Alexander Ashurkov, the code for REASSIGN  
OWNED hadn't gotten word about user mappings.  Deal with them in the  
same way default ACLs do, which is to ignore them altogether; they are  
handled just fine by DROP OWNED.  The other foreign object cases are  
already handled correctly by both commands.  
  
Also add a REASSIGN OWNED statement to foreign_data test to exercise the  
foreign data objects.  (The changes are just before the "cleanup" phase,  
so it shouldn't remove any existing live test.)  
  
Reported by Alexander Ashurkov, then independently by Jaime Casanova.  
  

Install our “missing” script where PGXS builds can find it.

  
commit   : 98467b35dbe2917dfad075cc5ae33896d3fe2461    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 11 Dec 2015 16:14:27 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 11 Dec 2015 16:14:27 -0500    

Click here for diff

  
This allows sane behavior in a PGXS build done on a machine where build  
tools such as bison are missing.  
  
Jim Nasby  
  

Fix bug leading to restoring unlogged relations from empty files.

  
commit   : 2de281da212e16ea198f0c8e3165a4d67fe5e7a4    
  
author   : Andres Freund <andres@anarazel.de>    
date     : Thu, 10 Dec 2015 16:25:12 +0100    
  
committer: Andres Freund <andres@anarazel.de>    
date     : Thu, 10 Dec 2015 16:25:12 +0100    

Click here for diff

  
At the end of crash recovery, unlogged relations are reset to the empty  
state, using their init fork as the template. The init fork is copied to  
the main fork without going through shared buffers. Unfortunately WAL  
replay so far has not necessarily flushed writes from shared buffers to  
disk at that point. In normal crash recovery, and before the  
introduction of 'fast promotions' in fd4ced523 / 9.3, the  
END_OF_RECOVERY checkpoint flushes the buffers out in time. But with  
fast promotions that's not the case anymore.  
  
To fix, force WAL writes targeting the init fork to be flushed  
immediately (using the new FlushOneBuffer() function). In 9.5+ that  
flush can centrally be triggered from the code dealing with restoring  
full page writes (XLogReadBufferForRedoExtended), in earlier releases  
that responsibility is in the hands of XLOG_HEAP_NEWPAGE's replay  
function.  
  
Backpatch to 9.1, even if this currently is only known to trigger in  
9.3+. Flushing earlier is more robust, and it is advantageous to keep  
the branches similar.  
  
Typical symptoms of this bug are errors like  
'ERROR:  index "..." contains unexpected zero page at block 0'  
shortly after promoting a node.  
  
Reported-By: Thom Brown  
Author: Andres Freund and Michael Paquier  
Discussion: 20150326175024.GJ451@alap3.anarazel.de  
Backpatch: 9.1-  
  

Accept flex > 2.5.x on Windows, too.

  
commit   : 7f94a5c106f88d5abbcc84e545962208fac9c232    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 10 Dec 2015 10:19:13 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 10 Dec 2015 10:19:13 -0500    

Click here for diff

  
Commit 32f15d05c fixed this in configure, but missed the similar check  
in the MSVC scripts.  
  
Michael Paquier, per report from Victor Wagner  
  

Further improve documentation of the role-dropping process.

  
commit   : 255cc9b2dbe4e7400af5268369bfddb68f7af6cf    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 4 Dec 2015 14:44:13 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 4 Dec 2015 14:44:13 -0500    

Click here for diff

  
In commit 1ea0c73c2 I added a section to user-manag.sgml about how to drop  
roles that own objects; but as pointed out by Stephen Frost, I neglected  
that shared objects (databases or tablespaces) may need special treatment.  
Fix that.  Back-patch to supported versions, like the previous patch.  
  

Make gincostestimate() cope with hypothetical GIN indexes.

  
commit   : 3d4bdd2f94a40a4fd5ea43d80d0bd262b280b033    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 1 Dec 2015 16:24:35 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 1 Dec 2015 16:24:35 -0500    

Click here for diff

  
We tried to fetch statistics data from the index metapage, which does not  
work if the index isn't actually present.  If the index is hypothetical,  
instead extrapolate some plausible internal statistics based on the index  
page count provided by the index-advisor plugin.  
  
There was already some code in gincostestimate() to invent internal stats  
in this way, but since it was only meant as a stopgap for pre-9.1 GIN  
indexes that hadn't been vacuumed since upgrading, it was pretty crude.  
If we want it to support index advisors, we should try a little harder.  
A small amount of testing says that it's better to estimate the entry pages  
as 90% of the index, not 100%.  Also, estimating the number of entries  
(keys) as equal to the heap tuple count could be wildly wrong in either  
direction.  Instead, let's estimate 100 entries per entry page.  
  
Perhaps someday somebody will want the index advisor to be able to provide  
these numbers more directly, but for the moment this should serve.  
  
Problem report and initial patch by Julien Rouhaud; modified by me to  
invent less-bogus internal statistics.  Back-patch to all supported  
branches, since we've supported index advisors since 9.0.  
  

Use “g” not “f” format in ecpg’s PGTYPESnumeric_from_double().

  
commit   : 74cf6defa79c64ce8ac3548210686abc3e8695d1    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 1 Dec 2015 11:42:25 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 1 Dec 2015 11:42:25 -0500    

Click here for diff

  
The previous coding could overrun the provided buffer size for a very large  
input, or lose precision for a very small input.  Adopt the methodology  
that's been in use in the equivalent backend code for a long time.  
  
Per private report from Bas van Schaik.  Back-patch to all supported  
branches.  
  

Fix failure to consider failure cases in GetComboCommandId().

  
commit   : 47e189b5a10fdc5b983d1917e6f641ee80fa500b    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 26 Nov 2015 13:23:02 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Thu, 26 Nov 2015 13:23:02 -0500    

Click here for diff

  
Failure to initially palloc the comboCids array, or to realloc it bigger  
when needed, left combocid's data structures in an inconsistent state that  
would cause trouble if the top transaction continues to execute.  Noted  
while examining a user complaint about the amount of memory used for this.  
(There's not much we can do about that, but it does point up that repalloc  
failure has a non-negligible chance of occurring here.)  
  
In HEAD/9.5, also avoid possible invocation of memcpy() with a null pointer  
in SerializeComboCIDState; cf commit 13bba0227.  
  

Be more paranoid about null return values from libpq status functions.

  
commit   : d44b4deaad9f347c2e83ab50c7252f14fad1ef63    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 25 Nov 2015 17:31:54 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 25 Nov 2015 17:31:54 -0500    

Click here for diff

  
PQhost() can return NULL in non-error situations, namely when a Unix-socket  
connection has been selected by default.  That behavior is a tad debatable  
perhaps, but for the moment we should make sure that psql copes with it.  
Unfortunately, do_connect() failed to: it could pass a NULL pointer to  
strcmp(), resulting in crashes on most platforms.  This was reported as a  
security issue by ChenQin of Topsec Security Team, but the consensus of  
the security list is that it's just a garden-variety bug with no security  
implications.  
  
For paranoia's sake, I made the keep_password test not trust PQuser or  
PQport either, even though I believe those will never return NULL given  
a valid PGconn.  
  
Back-patch to all supported branches.  
  

pg_upgrade: fix CopyFile() on Windows to fail on file existence

  
commit   : 0ca3c51e5520b423b17f498f6390129659ef68e0    
  
author   : Bruce Momjian <bruce@momjian.us>    
date     : Tue, 24 Nov 2015 17:18:27 -0500    
  
committer: Bruce Momjian <bruce@momjian.us>    
date     : Tue, 24 Nov 2015 17:18:27 -0500    

Click here for diff

  
Also fix getErrorText() to return the right error string on failure.  
This behavior now matches that of other operating systems.  
  
Report by Noah Misch  
  
Backpatch through 9.1  
  

Fix Windows builds in back branches.

  
commit   : 05c9bc0635e95119558820d4910a228934fc4bd5    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 23 Nov 2015 00:32:01 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 23 Nov 2015 00:32:01 -0500    

Click here for diff

  
I missed adding src/port/tar.c to the Windows build files when  
back-patching the addition of that file to 9.2 and 9.1.  
Per buildfarm.  
  

Adopt the GNU convention for handling tar-archive members exceeding 8GB.

  
commit   : b054ca03185abc074026eb5fa09692cd5139d477    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 21 Nov 2015 20:21:32 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 21 Nov 2015 20:21:32 -0500    

Click here for diff

  
The POSIX standard for tar headers requires archive member sizes to be  
printed in octal with at most 11 digits, limiting the representable file  
size to 8GB.  However, GNU tar and apparently most other modern tars  
support a convention in which oversized values can be stored in base-256,  
allowing any practical file to be a tar member.  Adopt this convention  
to remove two limitations:  
* pg_dump with -Ft output format failed if the contents of any one table  
exceeded 8GB.  
* pg_basebackup failed if the data directory contained any file exceeding  
8GB.  (This would be a fatal problem for installations configured with a  
table segment size of 8GB or more, and it has also been seen to fail when  
large core dump files exist in the data directory.)  
  
File sizes under 8GB are still printed in octal, so that no compatibility  
issues are created except in cases that would have failed entirely before.  
  
In addition, this patch fixes several bugs in the same area:  
  
* In 9.3 and later, we'd defined tarCreateHeader's file-size argument as  
size_t, which meant that on 32-bit machines it would write a corrupt tar  
header for file sizes between 4GB and 8GB, even though no error was raised.  
This broke both "pg_dump -Ft" and pg_basebackup for such cases.  
  
* pg_restore from a tar archive would fail on tables of size between 4GB  
and 8GB, on machines where either "size_t" or "unsigned long" is 32 bits.  
This happened even with an archive file not affected by the previous bug.  
  
* pg_basebackup would fail if there were files of size between 4GB and 8GB,  
even on 64-bit machines.  
  
* In 9.3 and later, "pg_basebackup -Ft" failed entirely, for any file size,  
on 64-bit big-endian machines.  
  
In view of these potential data-loss bugs, back-patch to all supported  
branches, even though removal of the documented 8GB limit might otherwise  
be considered a new feature rather than a bug fix.  
  

Fix handling of inherited check constraints in ALTER COLUMN TYPE (again).

  
commit   : c49279dfd5275c9ede9e7faf7d183a76bab680b0    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 20 Nov 2015 14:55:29 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 20 Nov 2015 14:55:29 -0500    

Click here for diff

  
The previous way of reconstructing check constraints was to do a separate  
"ALTER TABLE ONLY tab ADD CONSTRAINT" for each table in an inheritance  
hierarchy.  However, that way has no hope of reconstructing the check  
constraints' own inheritance properties correctly, as pointed out in  
bug #13779 from Jan Dirk Zijlstra.  What we should do instead is to do  
a regular "ALTER TABLE", allowing recursion, at the topmost table that  
has a particular constraint, and then suppress the work queue entries  
for inherited instances of the constraint.  
  
Annoyingly, we'd tried to fix this behavior before, in commit 5ed6546cf,  
but we failed to notice that it wasn't reconstructing the pg_constraint  
field values correctly.  
  
As long as I'm touching pg_get_constraintdef_worker anyway, tweak it to  
always schema-qualify the target table name; this seems like useful backup  
to the protections installed by commit 5f173040.  
  
In HEAD/9.5, get rid of get_constraint_relation_oids, which is now unused.  
(I could alternatively have modified it to also return conislocal, but that  
seemed like a pretty single-purpose API, so let's not pretend it has some  
other use.)  It's unused in the back branches as well, but I left it in  
place just in case some third-party code has decided to use it.  
  
In HEAD/9.5, also rename pg_get_constraintdef_string to  
pg_get_constraintdef_command, as the previous name did nothing to explain  
what that entry point did differently from others (and its comment was  
equally useless).  Again, that change doesn't seem like material for  
back-patching.  
  
I did a bit of re-pgindenting in tablecmds.c in HEAD/9.5, as well.  
  
Otherwise, back-patch to all supported branches.  
  

Accept flex > 2.5.x in configure.

  
commit   : 6e1d26f1f79a8ed9a8222d3f6b5ea5d4b667b23f    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 18 Nov 2015 17:45:06 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 18 Nov 2015 17:45:06 -0500    

Click here for diff

  
Per buildfarm member anchovy, 2.6.0 exists in the wild now.  
Hopefully it works with Postgres; if not, we'll have to do something  
about that, but in any case claiming it's "too old" is pretty silly.  
  

Fix possible internal overflow in numeric division.

  
commit   : c47bdb3726ba020b6e187e9279014e9a5e4df0d3    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 17 Nov 2015 15:46:47 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 17 Nov 2015 15:46:47 -0500    

Click here for diff

  
div_var_fast() postpones propagating carries in the same way as mul_var(),  
so it has the same corner-case overflow risk we fixed in 246693e5ae8a36f0,  
namely that the size of the carries has to be accounted for when setting  
the threshold for executing a carry propagation step.  We've not devised  
a test case illustrating the brokenness, but the required fix seems clear  
enough.  Like the previous fix, back-patch to all active branches.  
  
Dean Rasheed  
  

Fix ruleutils.c’s dumping of whole-row Vars in ROW() and VALUES() contexts.

  
commit   : ed824cf80d46ecd5bfd06d4cc65b075328b2db85    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 15 Nov 2015 14:41:09 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 15 Nov 2015 14:41:09 -0500    

Click here for diff

  
Normally ruleutils prints a whole-row Var as "foo.*".  We already knew that  
that doesn't work at top level of a SELECT list, because the parser would  
treat the "*" as a directive to expand the reference into separate columns,  
not a whole-row Var.  However, Joshua Yanovski points out in bug #13776  
that the same thing happens at top level of a ROW() construct; and some  
nosing around in the parser shows that the same is true in VALUES().  
Hence, apply the same workaround already devised for the SELECT-list case,  
namely to add a forced cast to the appropriate rowtype in these cases.  
(The alternative of just printing "foo" was rejected because it is  
difficult to avoid ambiguity against plain columns named "foo".)  
  
Back-patch to all supported branches.  
  

PL/Python: Make tests pass with Python 3.5

  
commit   : 82076c1e40eb93717ede3c82f59e7711090b63a8    
  
author   : Peter Eisentraut <peter_e@gmx.net>    
date     : Sat, 14 Nov 2015 12:44:38 -0500    
  
committer: Peter Eisentraut <peter_e@gmx.net>    
date     : Sat, 14 Nov 2015 12:44:38 -0500    

Click here for diff

  
The error message wording for AttributeError has changed in Python 3.5.  
For the plpython_error test, add a new expected file.  In the  
plpython_subtransaction test, we didn't really care what the exception  
is, only that it is something coming from Python.  So use a generic  
exception instead, which has a message that doesn't vary across  
versions.  
  

pg_upgrade: properly detect file copy failure on Windows

  
commit   : b4c4220ede3048662c746123b8af2a9101a1b313    
  
author   : Bruce Momjian <bruce@momjian.us>    
date     : Sat, 14 Nov 2015 11:47:11 -0500    
  
committer: Bruce Momjian <bruce@momjian.us>    
date     : Sat, 14 Nov 2015 11:47:11 -0500    

Click here for diff

  
Previously, file copy failures were ignored on Windows due to an  
incorrect return value check.  
  
Report by Manu Joye  
  
Backpatch through 9.1  
  

Improve our workaround for ‘TeX capacity exceeded’ in building PDF files.

  
commit   : e12a99c89e8106ee5700396836f423c03bb7816b    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 10 Nov 2015 15:59:59 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 10 Nov 2015 15:59:59 -0500    

Click here for diff

  
In commit a5ec86a7c787832d28d5e50400ec96a5190f2555 I wrote a quick hack  
that reduced the number of TeX string pool entries created while converting  
our documentation to PDF form.  That held the fort for awhile, but as of  
HEAD we're back up against the same limitation.  It turns out that the  
original coding of \FlowObjectSetup actually results in *three* string pool  
entries being generated for every "flow object" (that is, potential  
cross-reference target) in the documentation, and my previous hack only got  
rid of one of them.  With a little more care, we can reduce the string  
count to one per flow object plus one per actually-cross-referenced flow  
object (about 115000 + 5000 as of current HEAD); that should work until  
the documentation volume roughly doubles from where it is today.  
  
As a not-incidental side benefit, this change also causes pdfjadetex to  
stop emitting unreferenced hyperlink anchors (bookmarks) into the PDF file.  
It had been making one willy-nilly for every flow object; now it's just one  
per actually-cross-referenced object.  This results in close to a 2X  
savings in PDF file size.  We will still want to run the output through  
"jpdftweak" to get it to be compressed; but we no longer need removal of  
unreferenced bookmarks, so we might be able to find a quicker tool for  
that step.  
  
Although the failure only affects HEAD and US-format output at the moment,  
9.5 cannot be more than a few pages short of failing likewise, so it  
will inevitably fail after a few rounds of minor-version release notes.  
I don't have a lot of faith that we'll never hit the limit in the older  
branches; and anyway it would be nice to get rid of jpdftweak across the  
board.  Therefore, back-patch to all supported branches.  
  

Don’t connect() to a wildcard address in test_postmaster_connection().

  
commit   : 99027350e7030aa97644860f9c176683b05941b1    
  
author   : Noah Misch <noah@leadboat.com>    
date     : Sun, 8 Nov 2015 17:28:53 -0500    
  
committer: Noah Misch <noah@leadboat.com>    
date     : Sun, 8 Nov 2015 17:28:53 -0500    

Click here for diff

  
At least OpenBSD, NetBSD, and Windows don't support it.  This repairs  
pg_ctl for listen_addresses='0.0.0.0' and listen_addresses='::'.  Since  
pg_ctl prefers to test a Unix-domain socket, Windows users are most  
likely to need this change.  Back-patch to 9.1 (all supported versions).  
This could change pg_ctl interaction with loopback-interface firewall  
rules.  Therefore, in 9.4 and earlier (released branches), activate the  
change only on known-affected platforms.  
  
Reported (bug #13611) and designed by Kondo Yuta.  
  

Fix enforcement of restrictions inside regexp lookaround constraints.

  
commit   : bfb10db81ec9f4d2cb8de20c6af03463f89154c9    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 7 Nov 2015 12:43:24 -0500    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sat, 7 Nov 2015 12:43:24 -0500    

Click here for diff

  
Lookahead and lookbehind constraints aren't allowed to contain backrefs,  
and parentheses within them are always considered non-capturing.  Or so  
says the manual.  But the regexp parser forgot about these rules once  
inside a parenthesized subexpression, so that constructs like (\w)(?=(\1))  
were accepted (but then not correctly executed --- a case like this acted  
like (\w)(?=\w), without any enforcement that the two \w's match the same  
text).  And in (?=((foo))) the innermost parentheses would be counted as  
capturing parentheses, though no text would ever be captured for them.  
  
To fix, properly pass down the "type" argument to the recursive invocation  
of parse().  
  
Back-patch to all supported branches; it was agreed that silent  
misexecution of such patterns is worse than throwing an error, even though  
new errors in minor releases are generally not desirable.  
  

Fix serialization anomalies due to race conditions on INSERT.

  
commit   : caff7fc3fb1184d0fe39228cd8922e664006105b    
  
author   : Kevin Grittner <kgrittn@postgresql.org>    
date     : Sat, 31 Oct 2015 14:36:37 -0500    
  
committer: Kevin Grittner <kgrittn@postgresql.org>    
date     : Sat, 31 Oct 2015 14:36:37 -0500    

Click here for diff

  
On insert the CheckForSerializableConflictIn() test was performed  
before the page(s) which were going to be modified had been locked  
(with an exclusive buffer content lock).  If another process  
acquired a relation SIReadLock on the heap and scanned to a page on  
which an insert was going to occur before the page was so locked,  
a rw-conflict would be missed, which could allow a serialization  
anomaly to be missed.  The window between the check and the page  
lock was small, so the bug was generally not noticed unless there  
was high concurrency with multiple processes inserting into the  
same table.  
  
This was reported by Peter Bailis as bug #11732, by Sean Chittenden  
as bug #13667, and by others.  
  
The race condition was eliminated in heap_insert() by moving the  
check down below the acquisition of the buffer lock, which had been  
the very next statement.  Because of the loop locking and unlocking  
multiple buffers in heap_multi_insert() a check was added after all  
inserts were completed.  The check before the start of the inserts  
was left because it might avoid a large amount of work to detect a  
serialization anomaly before performing the all of the inserts and  
the related WAL logging.  
  
While investigating this bug, other SSI bugs which were even harder  
to hit in practice were noticed and fixed, an unnecessary check  
(covered by another check, so redundant) was removed from  
heap_update(), and comments were improved.  
  
Back-patch to all supported branches.  
  
Kevin Grittner and Thomas Munro  
  

Fix back-patch of commit 8e3b4d9d40244c037bbc6e182ea3fabb9347d482.

  
commit   : 887d9142622beef8f323fcb89b2a8a7156a367c2    
  
author   : Noah Misch <noah@leadboat.com>    
date     : Tue, 20 Oct 2015 00:57:25 -0400    
  
committer: Noah Misch <noah@leadboat.com>    
date     : Tue, 20 Oct 2015 00:57:25 -0400    

Click here for diff

  
master emits an extra context message compared to 9.5 and earlier.  
  

Eschew “RESET statement_timeout” in tests.

  
commit   : 934fdaaca80e981dac90cdd974f61e7d493a78bf    
  
author   : Noah Misch <noah@leadboat.com>    
date     : Tue, 20 Oct 2015 00:37:22 -0400    
  
committer: Noah Misch <noah@leadboat.com>    
date     : Tue, 20 Oct 2015 00:37:22 -0400    

Click here for diff

  
Instead, use transaction abort.  Given an unlucky bout of latency, the  
timeout would cancel the RESET itself.  Buildfarm members gharial,  
lapwing, mereswine, shearwater, and sungazer witness that.  Back-patch  
to 9.1 (all supported versions).  The query_canceled test still could  
timeout before entering its subtransaction; for whatever reason, that  
has yet to happen on the buildfarm.  
  

Fix incorrect handling of lookahead constraints in pg_regprefix().

  
commit   : 05e62ff59676af1583a0c61546669adbc1dc2f4c    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 19 Oct 2015 13:54:54 -0700    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 19 Oct 2015 13:54:54 -0700    

Click here for diff

  
pg_regprefix was doing nothing with lookahead constraints, which would  
be fine if it were the right kind of nothing, but it isn't: we have to  
terminate our search for a fixed prefix, not just pretend the LACON arc  
isn't there.  Otherwise, if the current state has both a LACON outarc and a  
single plain-color outarc, we'd falsely conclude that the color represents  
an addition to the fixed prefix, and generate an extracted index condition  
that restricts the indexscan too much.  (See added regression test case.)  
  
Terminating the search is conservative: we could traverse the LACON arc  
(thus assuming that the constraint can be satisfied at runtime) and then  
examine the outarcs of the linked-to state.  But that would be a lot more  
work than it seems worth, because writing a LACON followed by a single  
plain character is a pretty silly thing to do.  
  
This makes a difference only in rather contrived cases, but it's a bug,  
so back-patch to all supported branches.  
  

Fix order of arguments in ecpg generated typedef command.

  
commit   : 8f67643be199c0a770de9de3464b2c49e105294d    
  
author   : Michael Meskes <meskes@postgresql.org>    
date     : Fri, 16 Oct 2015 17:29:05 +0200    
  
committer: Michael Meskes <meskes@postgresql.org>    
date     : Fri, 16 Oct 2015 17:29:05 +0200    

Click here for diff

  
  

Miscellaneous cleanup of regular-expression compiler.

  
commit   : 2419ab8aa99b46bdf3a401501b5488b28870ee39    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 15:52:12 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 15:52:12 -0400    

Click here for diff

  
Revert our previous addition of "all" flags to copyins() and copyouts();  
they're no longer needed, and were never anything but an unsightly hack.  
  
Improve a couple of infelicities in the REG_DEBUG code for dumping  
the NFA data structure, including adding code to count the total  
number of states and arcs.  
  
Add a couple of missed error checks.  
  
Add some more documentation in the README file, and some regression tests  
illustrating cases that exceeded the state-count limit and/or took  
unreasonable amounts of time before this set of patches.  
  
Back-patch to all supported branches.  
  

Improve memory-usage accounting in regular-expression compiler.

  
commit   : 4e4610a8a13796d9969a7d6c28c34ec333b23ebb    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 15:36:17 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 15:36:17 -0400    

Click here for diff

  
This code previously counted the number of NFA states it created, and  
complained if a limit was exceeded, so as to prevent bizarre regex patterns  
from consuming unreasonable time or memory.  That's fine as far as it went,  
but the code paid no attention to how many arcs linked those states.  Since  
regexes can be contrived that have O(N) states but will need O(N^2) arcs  
after fixempties() processing, it was still possible to blow out memory,  
and take a long time doing it too.  To fix, modify the bookkeeping to count  
space used by both states and arcs.  
  
I did not bother with including the "color map" in the accounting; it  
can only grow to a few megabytes, which is not a lot in comparison to  
what we're allowing for states+arcs (about 150MB on 64-bit machines  
or half that on 32-bit machines).  
  
Looking at some of the larger real-world regexes captured in the Tcl  
regression test suite suggests that the most that is likely to be needed  
for regexes found in the wild is under 10MB, so I believe that the current  
limit has enough headroom to make it okay to keep it as a hard-wired limit.  
  
In connection with this, redefine REG_ETOOBIG as meaning "regular  
expression is too complex"; the previous wording of "nfa has too many  
states" was already somewhat inapropos because of the error code's use  
for stack depth overrun, and it was not very user-friendly either.  
  
Back-patch to all supported branches.  
  

Improve performance of pullback/pushfwd in regular-expression compiler.

  
commit   : a257b808a507649432246b2bd9733e733f5b6332    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 15:11:49 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 15:11:49 -0400    

Click here for diff

  
The previous coding would create a new intermediate state every time it  
wanted to interchange the ordering of two constraint arcs.  Certain regex  
features such as \Y can generate large numbers of parallel constraint arcs,  
and if we needed to reorder the results of that, we created unreasonable  
numbers of intermediate states.  To improve matters, keep a list of  
already-created intermediate states associated with the state currently  
being considered by the outer loop; we can re-use such states to place all  
the new arcs leading to the same destination or source.  
  
I also took the trouble to redefine push() and pull() to have a less risky  
API: they no longer delete any state or arc that the caller might possibly  
have a pointer to, except for the specifically-passed constraint arc.  
This reduces the risk of re-introducing the same type of error seen in  
the failed patch for CVE-2007-4772.  
  
Back-patch to all supported branches.  
  

Improve performance of fixempties() pass in regular-expression compiler.

  
commit   : 18b032f8ff156fc482202cddb46b4b457c55cf11    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 14:58:11 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 14:58:11 -0400    

Click here for diff

  
The previous coding took something like O(N^4) time to fully process a  
chain of N EMPTY arcs.  We can't really do much better than O(N^2) because  
we have to insert about that many arcs, but we can do lots better than  
what's there now.  The win comes partly from using mergeins() to amortize  
de-duplication of arcs across multiple source states, and partly from  
exploiting knowledge of the ordering of arcs for each state to avoid  
looking at arcs we don't need to consider during the scan.  We do have  
to be a bit careful of the possible reordering of arcs introduced by  
the sort-merge coding of the previous commit, but that's not hard to  
deal with.  
  
Back-patch to all supported branches.  
  

Fix O(N^2) performance problems in regular-expression compiler.

  
commit   : a2ad467ae4a09c79488044c552edfa40724f41c6    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 14:43:18 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 14:43:18 -0400    

Click here for diff

  
Change the singly-linked in-arc and out-arc lists to be doubly-linked,  
so that arc deletion is constant time rather than having worst-case time  
proportional to the number of other arcs on the connected states.  
  
Modify the bulk arc transfer operations copyins(), copyouts(), moveins(),  
moveouts() so that they use a sort-and-merge algorithm whenever there's  
more than a small number of arcs to be copied or moved.  The previous  
method is O(N^2) in the number of arcs involved, because it performs  
duplicate checking independently for each copied arc.  The new method may  
change the ordering of existing arcs for the destination state, but nothing  
really cares about that.  
  
Provide another bulk arc copying method mergeins(), which is unused as  
of this commit but is needed for the next one.  It basically is like  
copyins(), but the source arcs might not all come from the same state.  
  
Replace the O(N^2) bubble-sort algorithm used in carcsort() with a qsort()  
call.  
  
These changes greatly improve the performance of regex compilation for  
large or complex regexes, at the cost of extra space for arc storage during  
compilation.  The original tradeoff was probably fine when it was made, but  
now we care more about speed and less about memory consumption.  
  
Back-patch to all supported branches.  
  

Fix regular-expression compiler to handle loops of constraint arcs.

  
commit   : 83c34825e5b02880bdad2afdba7861590abe7fe7    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 14:14:41 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 16 Oct 2015 14:14:41 -0400    

Click here for diff

  
It's possible to construct regular expressions that contain loops of  
constraint arcs (that is, ^ $ AHEAD BEHIND or LACON arcs).  There's no use  
in fully traversing such a loop at execution, since you'd just end up in  
the same NFA state without having consumed any input.  Worse, such a loop  
leads to infinite looping in the pullback/pushfwd stage of compilation,  
because we keep pushing or pulling the same constraints around the loop  
in a vain attempt to move them to the pre or post state.  Such looping was  
previously recognized in CVE-2007-4772; but the fix only handled the case  
of trivial single-state loops (that is, a constraint arc leading back to  
its source state) ... and not only that, it was incorrect even for that  
case, because it broke the admittedly-not-very-clearly-stated API contract  
of the pull() and push() subroutines.  The first two regression test cases  
added by this commit exhibit patterns that result in assertion failures  
because of that (though there seem to be no ill effects in non-assert  
builds).  The other new test cases exhibit multi-state constraint loops;  
in an unpatched build they will run until the NFA state-count limit is  
exceeded.  
  
To fix, remove the code added for CVE-2007-4772, and instead create a  
general-purpose constraint-loop-breaking phase of regex compilation that  
executes before we do pullback/pushfwd.  Since we never need to traverse  
a constraint loop fully, we can just break the loop at any chosen spot,  
if we add clone states that can replicate any sequence of arc transitions  
that would've traversed just part of the loop.  
  
Also add some commentary clarifying why we have to have all these  
machinations in the first place.  
  
This class of problems has been known for some time --- we had a report  
from Marc Mamin about two years ago, for example, and there are related  
complaints in the Tcl bug tracker.  I had discussed a fix of this kind  
off-list with Henry Spencer, but didn't get around to doing something  
about it until the issue was rediscovered by Greg Stark recently.  
  
Back-patch to all supported branches.  
  

On Windows, ensure shared memory handle gets closed if not being used.

  
commit   : 39cd1bdb8655fc897e8cb77613c21acb677709d7    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 13 Oct 2015 11:21:33 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 13 Oct 2015 11:21:33 -0400    

Click here for diff

  
Postmaster child processes that aren't supposed to be attached to shared  
memory were not bothering to close the shared memory mapping handle they  
inherit from the postmaster process.  That's mostly harmless, since the  
handle vanishes anyway when the child process exits -- but the syslogger  
process, if used, doesn't get killed and restarted during recovery from a  
backend crash.  That meant that Windows doesn't see the shared memory  
mapping as becoming free, so it doesn't delete it and the postmaster is  
unable to create a new one, resulting in failure to recover from crashes  
whenever logging_collector is turned on.  
  
Per report from Dmitry Vasilyev.  It's a bit astonishing that we'd not  
figured this out long ago, since it's been broken from the very beginnings  
of out native Windows support; probably some previously-unexplained trouble  
reports trace to this.  
  
A secondary problem is that on Cygwin (perhaps only in older versions?),  
exec() may not detach from the shared memory segment after all, in which  
case these child processes did remain attached to shared memory, posing  
the risk of an unexpected shared memory clobber if they went off the rails  
somehow.  That may be a long-gone bug, but we can deal with it now if it's  
still live, by detaching within the infrastructure introduced here to deal  
with closing the handle.  
  
Back-patch to all supported branches.  
  
Tom Lane and Amit Kapila  
  

Fix “pg_ctl start -w” to test child process status directly.

  
commit   : 250108b6f3993e74a83b93c14fc09933799b3e11    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 12 Oct 2015 18:30:37 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Mon, 12 Oct 2015 18:30:37 -0400    

Click here for diff

  
pg_ctl start with -w previously relied on a heuristic that the postmaster  
would surely always manage to create postmaster.pid within five seconds.  
Unfortunately, that fails much more often than we would like on some of the  
slower, more heavily loaded buildfarm members.  
  
We have known for quite some time that we could remove the need for that  
heuristic on Unix by using fork/exec instead of system() to launch the  
postmaster.  This allows us to know the exact PID of the postmaster, which  
allows near-certain verification that the postmaster.pid file is the one  
we want and not a leftover, and it also lets us use waitpid() to detect  
reliably whether the child postmaster has exited or not.  
  
What was blocking this change was not wanting to rewrite the Windows  
version of start_postmaster() to avoid use of CMD.EXE.  That's doable  
in theory but would require fooling about with stdout/stderr redirection,  
and getting the handling of quote-containing postmaster switches to  
stay the same might be rather ticklish.  However, we realized that  
we don't have to do that to fix the problem, because we can test  
whether the shell process has exited as a proxy for whether the  
postmaster is still alive.  That doesn't allow an exact check of the  
PID in postmaster.pid, but we're no worse off than before in that  
respect; and we do get to get rid of the heuristic about how long the  
postmaster might take to create postmaster.pid.  
  
On Unix, this change means that a second "pg_ctl start -w" immediately  
after another such command will now reliably fail, whereas previously  
it would succeed if done within two seconds of the earlier command.  
Since that's a saner behavior anyway, it's fine.  On Windows, the case can  
still succeed within the same time window, since pg_ctl can't tell that the  
earlier postmaster's postmaster.pid isn't the pidfile it is looking for.  
To ensure stable test results on Windows, we can insert a short sleep into  
the test script for pg_ctl, ensuring that the existing pidfile looks stale.  
This hack can be removed if we ever do rewrite start_postmaster(), but that  
no longer seems like a high-priority thing to do.  
  
Back-patch to all supported versions, both because the current behavior  
is buggy and because we must do that if we want the buildfarm failures  
to go away.  
  
Tom Lane and Michael Paquier  
  

Improve documentation of the role-dropping process.

  
commit   : 539510582bc7bfd18c08fa5292e8061ddda68a33    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 7 Oct 2015 16:12:06 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Wed, 7 Oct 2015 16:12:06 -0400    

Click here for diff

  
In general one may have to run both REASSIGN OWNED and DROP OWNED to get  
rid of all the dependencies of a role to be dropped.  This was alluded to  
in the REASSIGN OWNED man page, but not really spelled out in full; and in  
any case the procedure ought to be documented in a more prominent place  
than that.  Add a section to the "Database Roles" chapter explaining this,  
and do a bit of wordsmithing in the relevant commands' man pages.  
  

Perform an immediate shutdown if the postmaster.pid file is removed.

  
commit   : 3d10f39709941f5562adf3d0fc4d61f91fac5ff5    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 6 Oct 2015 17:15:27 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Tue, 6 Oct 2015 17:15:27 -0400    

Click here for diff

  
The postmaster now checks every minute or so (worst case, at most two  
minutes) that postmaster.pid is still there and still contains its own PID.  
If not, it performs an immediate shutdown, as though it had received  
SIGQUIT.  
  
The original goal behind this change was to ensure that failed buildfarm  
runs would get fully cleaned up, even if the test scripts had left a  
postmaster running, which is not an infrequent occurrence.  When the  
buildfarm script removes a test postmaster's $PGDATA directory, its next  
check on postmaster.pid will fail and cause it to exit.  Previously, manual  
intervention was often needed to get rid of such orphaned postmasters,  
since they'd block new test postmasters from obtaining the expected socket  
address.  
  
However, by checking postmaster.pid and not something else, we can provide  
additional robustness: manual removal of postmaster.pid is a frequent DBA  
mistake, and now we can at least limit the damage that will ensue if a new  
postmaster is started while the old one is still alive.  
  
Back-patch to all supported branches, since we won't get the desired  
improvement in buildfarm reliability otherwise.