PostgreSQL 9.4.23 (upcoming) commit log

Fix some grammar in documentation of spgist

commit   : d93ba74c22c2cdbb978f84d51032486c3e05b5dc    
  
author   : Michael Paquier <michael@paquier.xyz>    
date     : Mon, 20 May 2019 09:49:00 +0900    
  
committer: Michael Paquier <michael@paquier.xyz>    
date     : Mon, 20 May 2019 09:49:00 +0900    

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Discussion: https://postgr.es/m/92961161-9b49-e42f-0a72-d5d47e0ed4de@postgrespro.ru  
Author: Liudmila Mantrova  
Reviewed-by: Jonathan Katz, Tom Lane, Michael Paquier  
Backpatch-through: 9.4  

M doc/src/sgml/spgist.sgml

Doc: Refer to line pointers as item identifiers.

commit   : bc96e394c23b66728349cbe429a3239a35fe29af    
  
author   : Peter Geoghegan <pg@bowt.ie>    
date     : Mon, 13 May 2019 15:38:57 -0700    
  
committer: Peter Geoghegan <pg@bowt.ie>    
date     : Mon, 13 May 2019 15:38:57 -0700    

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An upcoming HEAD-only patch will standardize the terminology around  
ItemIdData variables/line pointers, ending the practice of referring to  
them as "item pointers".  Make the "Database Page Layout" docs  
consistent with the new policy.  The term "item identifier" is already  
used in the same section, so stick with that.  
  
Discussion: https://postgr.es/m/CAH2-Wz=c=MZQjUzde3o9+2PLAPuHTpVZPPdYxN=E4ndQ2--8ew@mail.gmail.com  
Backpatch: All supported branches.  

M doc/src/sgml/storage.sgml

Fix misoptimization of “{1,1}” quantifiers in regular expressions.

commit   : b1ca28e57e1209769341451c07d7331c822f25a7    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 12 May 2019 18:53:13 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Sun, 12 May 2019 18:53:13 -0400    

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A bounded quantifier with m = n = 1 might be thought a no-op.  But  
according to our documentation (which traces back to Henry Spencer's  
original man page) it still imposes greediness, or non-greediness in the  
case of the non-greedy variant "{1,1}?", on whatever it's attached to.  
  
This turns out not to work though, because parseqatom() optimizes away  
the m = n = 1 case without regard for whether it's supposed to change  
the greediness of the argument RE.  
  
We can fix this by just not applying the optimization when the greediness  
needs to change; the subsequent general cases handle it fine.  
  
The three cases in which we can still apply the optimization are  
(a) no quantifier, or quantifier does not impose a preference;  
(b) atom has no greediness property, implying it cannot match a  
variable amount of text anyway; or  
(c) quantifier's greediness is same as atom's.  
Note that in most cases where one of these applies, we'd have exited  
earlier in the "not a messy case" fast path.  I think it's now only  
possible to get to the optimization when the atom involves capturing  
parentheses or a non-top-level backref.  
  
Back-patch to all supported branches.  I'd ordinarily be hesitant to  
put a subtle behavioral change into back branches, but in this case  
it's very hard to see a reason why somebody would write "{1,1}?" unless  
they're trying to get the documented change-of-greediness behavior.  
  
Discussion: https://postgr.es/m/5bb27a41-350d-37bf-901e-9d26f5592dd0@charter.net  

M src/backend/regex/regcomp.c
M src/test/regress/expected/regex.out
M src/test/regress/sql/regex.sql

Fail pgwin32_message_to_UTF16() for SQL_ASCII messages.

commit   : 08e3fd96f70a711b4d19927d792dde4a04672c15    
  
author   : Noah Misch <noah@leadboat.com>    
date     : Sun, 12 May 2019 10:33:05 -0700    
  
committer: Noah Misch <noah@leadboat.com>    
date     : Sun, 12 May 2019 10:33:05 -0700    

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The function had been interpreting SQL_ASCII messages as UTF8, throwing  
an error when they were invalid UTF8.  The new behavior is consistent  
with pg_do_encoding_conversion().  This affects LOG_DESTINATION_STDERR  
and LOG_DESTINATION_EVENTLOG, which will send untranslated bytes to  
write() and ReportEventA().  On buildfarm member bowerbird, enabling  
log_connections caused an error whenever the role name was not valid  
UTF8.  Back-patch to 9.4 (all supported versions).  
  
Discussion: https://postgr.es/m/20190512015615.GD1124997@rfd.leadboat.com  

M src/backend/utils/mb/mbutils.c

Fix error reporting in reindexdb

commit   : 82ed20e15e52c67cea1e3b3b1b8795cdbd249c05    
  
author   : Michael Paquier <michael@paquier.xyz>    
date     : Sat, 11 May 2019 13:01:29 +0900    
  
committer: Michael Paquier <michael@paquier.xyz>    
date     : Sat, 11 May 2019 13:01:29 +0900    

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When failing to reindex a table, reindexdb would generate an extra error  
message related to a database failure, which is misleading.  
  
Backpatch all the way down, as this has been introduced by 85e9a5a0.  
  
Discussion: https://postgr.es/m/CAOBaU_Yo61RwNO3cW6WVYWwH7EYMPuexhKqufb2nFGOdunbcHw@mail.gmail.com  
Author: Julien Rouhaud  
Reviewed-by: Daniel Gustafsson, Álvaro Herrera, Tom Lane, Michael  
Paquier  
Backpatch-through: 9.4  

M src/bin/scripts/reindexdb.c

Cope with EINVAL and EIDRM shmat() failures in PGSharedMemoryAttach.

commit   : b1cde67a4f94ada93eb314c7751e998377a0fa6a    
  
author   : Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 10 May 2019 14:56:41 -0400    
  
committer: Tom Lane <tgl@sss.pgh.pa.us>    
date     : Fri, 10 May 2019 14:56:41 -0400    

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There's a very old race condition in our code to see whether a pre-existing  
shared memory segment is still in use by a conflicting postmaster: it's  
possible for the other postmaster to remove the segment in between our  
shmctl() and shmat() calls.  It's a narrow window, and there's no risk  
unless both postmasters are using the same port number, but that's possible  
during parallelized "make check" tests.  (Note that while the TAP tests  
take some pains to choose a randomized port number, pg_regress doesn't.)  
If it does happen, we treated that as an unexpected case and errored out.  
  
To fix, allow EINVAL to be treated as segment-not-present, and the same  
for EIDRM on Linux.  AFAICS, the considerations here are basically  
identical to the checks for acceptable shmctl() failures, so I documented  
and coded it that way.  
  
While at it, adjust PGSharedMemoryAttach's API to remove its undocumented  
dependency on UsedShmemSegAddr in favor of passing the attach address  
explicitly.  This makes it easier to be sure we're using a null shmaddr  
when probing for segment conflicts (thus avoiding questions about what  
EINVAL means).  I don't think there was a bug there, but it required  
fragile assumptions about the state of UsedShmemSegAddr during  
PGSharedMemoryIsInUse.  
  
Commit c09850992 may have made this failure more probable by applying  
the conflicting-segment tests more often.  Hence, back-patch to all  
supported branches, as that was.  
  
Discussion: https://postgr.es/m/22224.1557340366@sss.pgh.pa.us  

M src/backend/port/sysv_shmem.c

Fix documentation for the privileges required for replication functions.

commit   : bc250ee7ebd0ff3b5bd1674fbf90a90032bad0fa    
  
author   : Fujii Masao <fujii@postgresql.org>    
date     : Thu, 9 May 2019 01:35:13 +0900    
  
committer: Fujii Masao <fujii@postgresql.org>    
date     : Thu, 9 May 2019 01:35:13 +0900    

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Previously it's documented that use of replication functions is  
restricted to superusers. This is true for the functions which  
use replication origin, but not for pg_logicl_emit_message() and  
functions which use replication slot. For example, not only  
superusers but also users with REPLICATION privilege is allowed  
to use the functions for replication slot. This commit fixes  
the documentation for the privileges required for those replication  
functions.  
  
Back-patch to 9.4 (all supported versions).  
  
Author: Matsumura Ryo  
Discussion: https://postgr.es/m/03040DFF97E6E54E88D3BFEE5F5480F74ABA6E16@G01JPEXMBYT04  

M doc/src/sgml/func.sgml

Remove leftover reference to old “flat file” mechanism in a comment.

commit   : 46012d152f8d123ddc9c739aed06d093b8553b66    
  
author   : Heikki Linnakangas <heikki.linnakangas@iki.fi>    
date     : Wed, 8 May 2019 09:32:34 +0300    
  
committer: Heikki Linnakangas <heikki.linnakangas@iki.fi>    
date     : Wed, 8 May 2019 09:32:34 +0300    

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The flat file mechanism was removed in PostgreSQL 9.0.  

M src/backend/access/transam/xact.c

commit   : 9a6a1042ab406de4eebcd307a1220c5552567748    
  
author   : Michael Paquier <michael@paquier.xyz>    
date     : Tue, 7 May 2019 14:20:24 +0900    
  
committer: Michael Paquier <michael@paquier.xyz>    
date     : Tue, 7 May 2019 14:20:24 +0900    

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This code was broken as of 582edc3, and is most likely not used anymore.  
Note that pg_dump supports servers down to 8.0, and psql has code to  
support servers down to 7.4.  
  
Author: Julien Rouhaud  
Reviewed-by: Tom Lane  
Discussion: https://postgr.es/m/CAOBaU_Y5y=zo3+2gf+2NJC1pvMYPcbRXoQaPXx=U7+C8Qh4CzQ@mail.gmail.com  

M src/bin/scripts/common.c