Add OVERLAPS to index in the docs.

Per report from Adam Mackler and Jonathan Katz
Fix calculation of ISMN check digit.

This has always been broken, so back-patch to all supported versions.

Fabien COELHO
Fix possible buffer overrun in contrib/pg_trgm.

Allow for the possibility that folding a string to lower case makes it
longer (due to replacing a character with a longer multibyte character).
This doesn't change the number of trigrams that will be extracted, but
it does affect the required size of an intermediate buffer in
generate_trgm().  Per bug #8821 from Ufuk Kayserilioglu.

Also install some checks that the input string length is not so large
as to cause overflow in the calculations of palloc request sizes.

Back-patch to all supported versions.
Fix multiple bugs in index page locking during hot-standby WAL replay.

In ordinary operation, VACUUM must be careful to take a cleanup lock on
each leaf page of a btree index; this ensures that no indexscans could
still be "in flight" to heap tuples due to be deleted.  (Because of
possible index-tuple motion due to concurrent page splits, it's not enough
to lock only the pages we're deleting index tuples from.)  In Hot Standby,
the WAL replay process must likewise lock every leaf page.  There were
several bugs in the code for that:

* The replay scan might come across unused, all-zero pages in the index.
While btree_xlog_vacuum itself did the right thing (ie, nothing) with
such pages, xlogutils.c supposed that such pages must be corrupt and
would throw an error.  This accounts for various reports of replication
failures with "PANIC: WAL contains references to invalid pages".  To
fix, add a ReadBufferMode value that instructs XLogReadBufferExtended
not to complain when we're doing this.

* btree_xlog_vacuum performed the extra locking if standbyState ==
STANDBY_SNAPSHOT_READY, but that's not the correct test: we won't open up
for hot standby queries until the database has reached consistency, and
we don't want to do the extra locking till then either, for fear of reading
corrupted pages (which bufmgr.c would complain about).  Fix by exporting a
new function from xlog.c that will report whether we're actually in hot
standby replay mode.

* To ensure full coverage of the index in the replay scan, btvacuumscan
would emit a dummy WAL record for the last page of the index, if no
vacuuming work had been done on that page.  However, if the last page
of the index is all-zero, that would result in corruption of said page,
since the functions called on it weren't prepared to handle that case.
There's no need to lock any such pages, so change the logic to target
the last normal leaf page instead.

The first two of these bugs were diagnosed by Andres Freund, the other one
by me.  Fixes based on ideas from Heikki Linnakangas and myself.

This has been wrong since Hot Standby was introduced, so back-patch to 9.0.
Improve FILES section of psql reference page.

Primarily, explain where to find the system-wide psqlrc file, per recent
gripe from John Sutton.  Do some general wordsmithing and improve the
markup, too.

Also adjust psqlrc.sample so its comments about file location are somewhat
trustworthy.  (Not sure why we bother with this file when it's empty,
but whatever.)

Back-patch to 9.2 where the startup file naming scheme was last changed.
Fix Hot Standby feedback sending when streaming busily.

Commit 6f60fdd7015b032bf49273c99f80913d57eac284 accidentally removed a
call to XLogWalRcvSendHSFeedback() after flushing received WAL to disk.
The consequence is that when walsender is busy streaming WAL, it doesn't
send HS feedback messages. One is sent if nothing is received from the
master for 100ms, but if there's a steady stream of WAL, it never happens.

Backpatch to 9.3.

Andres Freund and Amit Kapila
Fix client-only installation

The psql Makefile was not creating $(datadir) before installing
psqlrc.sample there.

In most cases, the directory would be created in some other way, but for
the documented from-source client-only installation procedure, it could
fail.

Reported-by: Mike Blackwell <mike.blackwell@rrd.com>
Allow SET TABLESPACE to database default

We've always allowed CREATE TABLE to create tables in the database's default
tablespace without checking for CREATE permissions on that tablespace.
Unfortunately, the original implementation of ALTER TABLE ... SET TABLESPACE
didn't pick up on that exception.

This changes ALTER TABLE ... SET TABLESPACE to allow the database's default
tablespace without checking for CREATE rights on that tablespace, just as
CREATE TABLE works today.  Users could always do this through a series of
commands (CREATE TABLE ... AS SELECT * FROM ...; DROP TABLE ...; etc), so
let's fix the oversight in SET TABLESPACE's original implementation.
Plug more memory leaks when reloading config file.

Commit 138184adc5f7c60c184972e4d23f8cdb32aed77d plugged some but not
all of the leaks from commit 2a0c81a12c7e6c5ac1557b0f1f4a581f23fd4ca7.
This tightens things up some more.

Amit Kapila, per an observation by Tom Lane
Fix inadvertent semantics change in last patch to plug memory leaks.

Commit a5bca4ef034f71175d46462963af2329d22068c2 accidentally changed
the semantics when the "skipping missing configuration file" is
emitted, because it forced OK to true instead of leaving the value
untouched.

Spotted by Tom Lane.
Tweak parse location assignment for CURRENT_DATE and related constructs.

All these constructs generate parse trees consisting of a Const and
a run-time type coercion (perhaps a FuncExpr or a CoerceViaIO).  Modify
the raw parse output so that we end up with the original token's location
attached to the type coercion node while the Const has location -1;
before, it was the other way around.  This makes no difference in terms
of what exprLocation() will say about the parse tree as a whole, so it
should not have any user-visible impact.  The point of changing it is that
we do not want contrib/pg_stat_statements to treat these constructs as
replaceable constants.  It will do the right thing if the Const has
location -1 rather than a valid location.

This is a pretty ugly hack, but then this code is ugly already; we should
someday replace this translation with special-purpose parse node(s) that
would allow ruleutils.c to reconstruct the original query text.

(See also commit 5d3fcc4c2e137417ef470d604fee5e452b22f6a7, which also
hacked location assignment rules for the benefit of pg_stat_statements.)

Back-patch to 9.2 where pg_stat_statements grew the ability to recognize
replaceable constants.

Kyotaro Horiguchi
Allow type_func_name_keywords in even more places

A while back, 2c92edad48796119c83d7dbe6c33425d1924626d allowed
type_func_name_keywords to be used in more places, including role
identifiers.  Unfortunately, that commit missed out on cases where
name_list was used for lists-of-roles, eg: for DROP ROLE.  This
resulted in the unfortunate situation that you could CREATE a role
with a type_func_name_keywords-allowed identifier, but not DROP it
(directly- ALTER could be used to rename it to something which
could be DROP'd).

This extends allowing type_func_name_keywords to places where role
lists can be used.

Back-patch to 9.0, as 2c92edad48796119c83d7dbe6c33425d1924626d was.
Fix bugs in PQhost().

In the platform that doesn't support Unix-domain socket, when
neither host nor hostaddr are specified, the default host
'localhost' is used to connect to the server and PQhost() must
return that, but it didn't. This patch fixes PQhost() so that
it returns the default host in that case.

Also this patch fixes PQhost() so that it doesn't return
Unix-domain socket directory path in the platform that doesn't
support Unix-domain socket.

Back-patch to all supported versions.
Avoid minor leak in parallel pg_dump

During parallel pg_dump, a worker process closing the connection caused
a minor memory leak (particularly minor as we are likely about to exit
anyway).  Instead, free the memory in this case prior to returning NULL
to indicate connection closed.

Spotting by the Coverity scanner.

Back patch to 9.3 where this was introduced.
Enable building with Visual Studion 2013.

Backpatch to 9.3.

Brar Piening.
Fix unsafe references to errno within error messaging logic.

Various places were supposing that errno could be expected to hold still
within an ereport() nest or similar contexts.  This isn't true necessarily,
though in some cases it accidentally failed to fail depending on how the
compiler chanced to order the subexpressions.  This class of thinko
explains recent reports of odd failures on clang-built versions, typically
missing or inappropriate HINT fields in messages.

Problem identified by Christian Kruse, who also submitted the patch this
commit is based on.  (I fixed a few issues in his patch and found a couple
of additional places with the same disease.)

Back-patch as appropriate to all supported branches.
docs:  add mention of index swapping

Backpatch to 9.3

Greg Smith
Fix bogus handling of "postponed" lateral quals.

When pulling a "postponed" qual from a LATERAL subquery up into the quals
of an outer join, we must make sure that the postponed qual is included
in those seen by make_outerjoininfo().  Otherwise we might compute a
too-small min_lefthand or min_righthand for the outer join, leading to
"JOIN qualification cannot refer to other relations" failures from
distribute_qual_to_rels.  Subtler errors in the created plan seem possible,
too, if the extra qual would only affect join ordering constraints.

Per bug #9041 from David Leverton.  Back-patch to 9.3.
Fix potential coredump on bad locale value in pg_upgrade.

Thinko in error report (and a typo in the message text, too).  We're
failing anyway, but it would be good to print something useful first.
Noted while reviewing a patch to make pg_upgrade's locale code laxer.
doc: mention data page checksums in WAL section

Backpatch to 9.3

Adjusted patch from Ian Lawrence Barwick