Reported-by: Daniel Verite <daniel@manitou-mail.org>

The function hash table keys made by compute_function_hashkey() failed
to distinguish event-trigger call context from regular call context.
This meant that once we'd successfully made a hash entry for an event
trigger (either by validation, or by normal use as an event trigger),
an attempt to call the trigger function as a plain function would
find this hash entry and thereby bypass the you-can't-do-that check in
do_compile().  Thus we'd attempt to execute the function, leading to
strange errors or even crashes, depending on function contents and
server version.

To fix, add an isEventTrigger field to PLpgSQL_func_hashkey,
paralleling the longstanding infrastructure for regular triggers.
This fits into what had been pad space, so there's no risk of an ABI
break, even assuming that any third-party code is looking at these
hash keys.  (I considered replacing isTrigger with a PLpgSQL_trigtype
enum field, but felt that that carried some API/ABI risk.  Maybe we
should change it in HEAD though.)

Per bug #16266 from Alexander Lakhin.  This has been broken since
event triggers were invented, so back-patch to all supported branches.

Discussion: https://postgr.es/m/16266-fcd7f838e97ba5d4@postgresql.org

It was set to immutable.  This was a mistake in the initial
commit (5925e554).
Reported-by: hubert depesz lubaczewski <depesz@depesz.com>
Discussion: https://www.postgresql.org/message-id/flat/20200218185452.GA8710%40depesz.com

  * Separate calculation of hash value from the lookup.
  * Split build_hash_table() into two functions.
  * Change lookup_hash_entry() to return AggStatePerGroup. That's all
    the caller needed, anyway.

These changes are to support the upcoming Disk-based Hash Aggregation
work.

Discussion: https://postgr.es/m/31f5ab871a3ad5a1a91a7a797651f20e77ac7ce3.camel%40j-davis.com

Prior to this commit, the read buffer was allocated at the time the tape
was rewound; but as an optimization, would not be allocated at all if
the tape was empty.

That optimization meant that it was valid to have a rewound tape with
the buffer set to NULL, but only if a number of conditions were met
and only if the API was used properly. After 7fdd919a refactored the
code to support lazily-allocating the buffer, Coverity started
complaining.

The optimization for empty tapes doesn't seem important, so just
allocate the buffer whether the tape has any data or not.

Discussion: https://postgr.es/m/20351.1581868306%40sss.pgh.pa.us

VACUUM may truncate heap in several batches. The activity report
is logged for each batch, and contains the number of pages in the table
before and after the truncation, and also the elapsed time during
the truncation. Previously the elapsed time reported in each batch was
the total elapsed time since starting the truncation until finishing
each batch. For example, if the truncation was processed dividing into
three batches, the second batch reported the accumulated time elapsed
during both first and second batches. This is strange and confusing
because the number of pages in the table reported together is not
total. Instead, each batch should report the time elapsed during
only that batch.

The cause of this issue was that the resource usage snapshot was
initialized only at the beginning of the truncation and was never
reset later. This commit fixes the issue by changing VACUUM so that
the resource usage snapshot is reset at each batch.

Back-patch to all supported branches.

Reported-by: Tatsuhito Kasahara
Author: Tatsuhito Kasahara
Reviewed-by: Masahiko Sawada, Fujii Masao
Discussion: https://postgr.es/m/CAP0=ZVJsf=NvQuy+QXQZ7B=ZVLoDV_JzsVC1FRsF1G18i3zMGg@mail.gmail.com

This fixes and updates a couple of comments related to outdated Windows
versions.  Particularly, src/common/exec.c had a fallback implementation
to read a file's line from a pipe because stdin/stdout/stderr does not
exist in Windows 2000 that is removed to simplify src/common/ as there
are unlikely versions of Postgres running on such platforms.

Author: Michael Paquier
Reviewed-by: Kyotaro Horiguchi, Juan José Santamaría Flecha
Discussion: https://postgr.es/m/20191219021526.GC4202@paquier.xyz

Manifested as

ERROR:  subtransaction logged without previous top-level txn record

this check forbids legit behaviours like
 - First xl_xact_assignment record is beyond reading, i.e. earlier
   restart_lsn.
 - After restart_lsn there is some change of a subxact.
 - After that, there is second xl_xact_assignment (for another subxact)
   revealing the relationship between top and first subxact.

Such a transaction won't be streamed anyway because we hadn't seen it in
full.  Saying for sure whether xact of some record encountered after
the snapshot was deserialized can be streamed or not requires to know
whether it wrote something before deserialization point --if yes, it
hasn't been seen in full and can't be decoded. Snapshot doesn't have such
info, so there is no easy way to relax the check.

Reported-by: Hsu, John
Diagnosed-by: Arseny Sher
Author: Arseny Sher, Amit Kapila
Reviewed-by: Amit Kapila, Dilip Kumar
Backpatch-through: 9.5
Discussion: https://postgr.es/m/AB5978B2-1772-4FEE-A245-74C91704ECB0@amazon.com

btbuild() has nothing to say about how NULL values compare in nbtree.
Besides, there are _bt_compare() header comments that describe how NULL
values are handled.

Previously, LOCK TABLE command through a parent table checked
the permissions on not only the parent table but also the children
tables inherited from it. This was a bug and inherited queries should
perform access permission checks on the parent table only. This
commit fixes LOCK TABLE so that it does not check the permission
on children tables.

This patch is applied only in the master branch. We decided not to
back-patch because it's not hard to imagine that there are some
applications expecting the old behavior and the change breaks their
security.

Author: Amit Langote
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/CAHGQGwE+GauyG7POtRfRwwthAGwTjPQYdFHR97+LzA4RHGnJxA@mail.gmail.com

Author: Daniel Gustafsson
Reviewed-by: Vik Fearing
Discussion: https://postgr.es/m/EBC3BFEB-664C-4063-81ED-29F1227DB012@yesql.se

This is related to progress reporting for ANALYZE and partitioned
tables.

Author: Amit Langote
Reviewed-by: Daniel Gustafsson, Julien Rouhaud
Discussion: https://postgr.es/m/CA+HiwqGx6C=-bFTX=ryMThyvM7CcSC3b1x8_6zh4Uo41Kvu-zw@mail.gmail.com

This was unaccountably omitted in the original RLS patch.
The SQL syntax is basically the same as for comments on triggers,
so crib code from dumpTrigger().

Per report from Marc Munro.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/1581889298.18009.15.camel@bloodnok.com

When updating a table row with generated columns, only recompute those
generated columns whose base columns have changed in this update and
keep the rest unchanged.  This can result in a significant performance
benefit.  The required information was already kept in
RangeTblEntry.extraUpdatedCols; we just have to make use of it.
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/b05e781a-fa16-6b52-6738-761181204567@2ndquadrant.com

The extraUpdatedCols field of the target RTE records which generated
columns are affected by an update.  This is used in a variety of
places, including per-column triggers and foreign data wrappers.  When
an update was initiated by a logical replication subscription, this
field was not filled in, so such an update would not affect generated
columns in a way that is consistent with normal updates.  To fix,
factor out some code from analyze.c to fill in extraUpdatedCols in the
logical replication worker as well.
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/b05e781a-fa16-6b52-6738-761181204567@2ndquadrant.com

This commit also updates wait event enum into alphabetical order.
Previously the enum entry for GSSOpenServer was added out-of-order.

Back-patch to v12 where commit b0b39f72 introduced
GSSOpenServer wait event. In v12, the commit doesn't include
the update of wait event enum, not to break ABI.

Author: Fujii Masao
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/949931aa-4ed4-d867-a7b5-de9c02b2292b@oss.nttdata.com

Back-patch to v10 where commit 249cf070 introduced
LogicalRewriteTruncate wait event.

Author: Fujii Masao
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/949931aa-4ed4-d867-a7b5-de9c02b2292b@oss.nttdata.com

Commit 0da33c76 introduced an unfortunate regression in pg_ctl on
Windows: if the log file specified with -l doesn't exist yet, and
pg_ctl is running with Administrator privileges, then the log file
might get created with permissions that prevent the postmaster from
writing on it.  (It seems that whether this happens depends on whether
the log file is inside the user's home directory or not, and perhaps
on other phase-of-the-moon conditions, which may explain why we failed
to notice it sooner.)

To fix, just don't create the log file if it doesn't exist yet.  The
case where we need to wait obviously only occurs with a pre-existing
log file.

In passing, switch from using fopen() to plain open(), saving a few
cycles.

Per bug #16259 from Jonathan Katz and Heath Lord.  Back-patch to v12,
as the faulty commit was.

Alexander Lakhin

Discussion: https://postgr.es/m/16259-c5ebed32a262a8b1@postgresql.org

Noted by Justin Pryzby, though I chose to just rip out the stale text,
as it's in no way relevant to this particular function.

Discussion: https://postgr.es/m/20200212182337.GZ1412@telsasoft.com

Make it a bit shorter and better-commented; no functional change.

Alvaro Herrera and Tom Lane

Discussion: https://postgr.es/m/20200212182337.GZ1412@telsasoft.com

Mostly to make sure the previous commit didn't break this.

Discussion: https://postgr.es/m/20200212182337.GZ1412@telsasoft.com

Practically everybody who's ever added a column to one of the bootstrap
catalogs has been burnt by the need to update the relnatts field in the
initial pg_class data to match.  Now that we use Perl scripts to
generate postgres.bki, we can have the machines take care of that,
by filling the field during genbki.pl.

While at it, use the BKI_DEFAULTS mechanism to eliminate repetitive
specifications of other column values in pg_class.dat, too.  They
weren't particularly a maintenance problem, but this way is prettier
(certainly the spotty previous usage of BKI_DEFAULTS wasn't pretty).

No catversion bump needed, since this doesn't actually change the
contents of postgres.bki.

Per gripe from Justin Pryzby, though this is quite different from
his originally proposed solution.

Amit Langote, John Naylor, Tom Lane

Discussion: https://postgr.es/m/20200212182337.GZ1412@telsasoft.com

The stylesheets used for the HTML documentation rendered on
postgresql.org have shifted, and no longer matched what was expected by
"make STYLE=website html" builds performed locally.  Local doc builds
did not reflect other aspects of the website, including font and
margins.

This patch updates the references to use the current set of stylesheets
that are used by the documentation on postgresql.org. This also wraps
the documentation preview in a HTML container so it can keep the content
within similar margins to those found on the website.

The documentation on building the docs is updated to reflect this
change, and to let the documentation builder know that an external
network connection is required to properly preview documentation built
with "make STYLE=website html" (which was true prior to this patch too,
but not mentioned).

Author: Jonathan Katz
Reported-By: Tom Lane
Discussion: https://postgr.es/m/1375.1581446233@sss.pgh.pa.us

We haven't used this option since inventing extensions.  As of commit
50fc694e it's actually formally equivalent to --load-extension, so
let's just drop it.

Discussion: https://postgr.es/m/6853.1581627393@sss.pgh.pa.us

Since its introduction in fe59e566, the code in charge of validating and
converting a file path includes some extra handling for absolute paths
pointing to an external log_directory, but this has never been used.

Author: Antonin Houska
Reviewed-by: Julien Rouhaud, Michael Paquier
Discussion: https://postgr.es/m/32663.1581592539@antos

This allows these modules to be installed into a database without
superuser privileges (assuming that the DBA or sysadmin has installed
the module's files in the expected place).  You only need CREATE
privilege on the current database, which by default would be
available to the database owner.

The following modules are marked trusted:

btree_gin
btree_gist
citext
cube
dict_int
earthdistance
fuzzystrmatch
hstore
hstore_plperl
intarray
isn
jsonb_plperl
lo
ltree
pg_trgm
pgcrypto
seg
tablefunc
tcn
tsm_system_rows
tsm_system_time
unaccent
uuid-ossp

In the future we might mark some more modules trusted, but there
seems to be no debate about these, and on the whole it seems wise
to be conservative with use of this feature to start out with.

Discussion: https://postgr.es/m/32315.1580326876@sss.pgh.pa.us

The write buffer was already lazily-allocated, so this is more
symmetric. It also means that a freshly-rewound tape (whether for
reading or writing) is not consuming memory for the buffer.

Discussion: https://postgr.es/m/97c46a59c27f3c38e486ca170fcbc618d97ab049.camel%40j-davis.com

Commit 6bf0bc84 replaced float.c's CHECKFLOATVAL() macro with static
inline subroutines, but that wasn't too well thought out.  In the original
coding, the unlikely condition (isinf(result) or result == 0) was checked
first, and the inf_is_valid or zero_is_valid condition only afterwards.
The inline-subroutine coding caused that to be swapped around, which is
pretty horrid for performance because (a) in common cases the is_valid
condition is twice as expensive to evaluate (e.g., requiring two isinf()
calls not one) and (b) in common cases the is_valid condition is false,
requiring us to perform the unlikely-condition check anyway.  Net result
is that one isinf() call becomes two or three, resulting in visible
performance loss as reported by Keisuke Kuroda.

The original fix proposal was to revert the replacement of the macro,
but on second thought, that macro was just a bad idea from the beginning:
if anything it's a net negative for readability of the code.  So instead,
let's just open-code all the overflow/underflow tests, being careful to
test the unlikely condition first (and mark it unlikely() to help the
compiler get the point).

Also, rather than having N copies of the actual ereport() calls, collapse
those into out-of-line error subroutines to save some code space.  This
does mean that the error file/line numbers won't be very helpful for
figuring out where the issue really is --- but we'd already burned that
bridge by putting the ereports into static inlines.

In HEAD, check_float[48]_val() are gone altogether.  In v12, leave them
present in float.h but unused in the core code, just in case some
extension is depending on them.

Emre Hasegeli, with some kibitzing from me and Andres Freund

Discussion: https://postgr.es/m/CANDwggLe1Gc1OrRqvPfGE=kM9K0FSfia0hbeFCEmwabhLz95AA@mail.gmail.com

Use a top-level "variablelist", with one item per B-Tree support
function.  This structure matches the structure used by various
"Extensibility" sections in other documentation chapters for other index
access methods.

An explicit list makes it much clearer where each item begins and ends.
This wasn't really a problem before now, but an upcoming patch that adds
deduplication to nbtree will need to have its own new B-Tree support
function.  Ease the burden of translators by tidying up btree.sgml ahead
of committing the deduplication patch.

These should've been dropped by a8bb8eb5, but evidently were
missed.  Not important enough to back-patch.

The GRANTED BY clause in GRANT/REVOKE ROLE has been there since 2005
but was never documented.  I'm not sure now whether that was just an
oversight or was intentional (given the limited capability of the
option).  But seeing that pg_dumpall does emit code that uses this
option, it seems like not documenting it at all is a bad idea.

Also, when we upgraded the syntax to allow CURRENT_USER/SESSION_USER
as the privilege recipient, the role form of GRANT was incorrectly
not modified to show that, and REVOKE's docs weren't touched at all.

Although I'm not that excited about GRANTED BY, the other oversight
seems serious enough to justify a back-patch.

Discussion: https://postgr.es/m/3070.1581526786@sss.pgh.pa.us

Looks like guaibasaurus had a autovacuum running during the
controller_print_speculative_locks step (just added in
43e08419). Which does indeed seem quite possible.

Avoid the problem by only looking for the backends participating in
the test.

%d can be used to track if the current connection is in a transaction
block or not, and adding it by default to the prompt has the advantage
to not need a modification of .psqlrc, something not possible depending
on the environment.

This discussion has happened across various sources, and there was a
strong consensus in favor of this change.

Author: Vik Fearing
Reviewed-by: Fabien Coelho
Discussion: https://postgr.es/m/09502c40-cfe1-bb29-10f9-4b3fa7b2bbb2@2ndquadrant.com

Previously, the speculative insert tests did not cover the case when a
tuple t is inserted into a table with a unique index on a column but
before it can insert into the index, a concurrent transaction has
inserted a conflicting value into the index and the insertion of tuple t
must be aborted.

The basic permutation is one session successfully inserts into the table
and an associated unique index while a concurrent session successfully
inserts into the table but discovers a conflict before inserting into
the index and must abort the insertion.

Several variants on this include:
- swap which session is successful
- first session insert transaction does not commit, so second session
must wait on a transaction lock
- first session insert does not "complete", so second session must wait
on a speculative insertion lock

Also, refactor the existing TOAST table upsert test to be in the same
spec and reuse the steps.

Author: Melanie Plageman, Ashwin Agrawal, Andres Freund
Reviewed-by: Andres Freund, Taylor Vesely
Discussion: https://postgr.es/m/CAAKRu_ZRmxy_OEryfY3G8Zp01ouhgw59_-_Cm8n7LzRH5BAvng@mail.gmail.com

Commit caba97a9 changed pg_basebackup -F plain -R so that
it overwrote postgresql.auto.conf in the backup, with new connection
setting. This could cause the existing postgresql.auto.conf settings
in the server to get lost unexpectedly. This is a bug.

This commit fixes the bug by making pg_basebackup -F plain -R
append the connection setting into postgresql.auto.conf in the backup.

Author: Fujii Masao
Reviewed-by: Sergei Kornilov
Discussion: https://postgr.es/m/250dcf2a-94e7-c05e-824a-73cfb38a48a4@oss.nttdata.com

This removes some lseek() system calls.

Author: Thomas Munro
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/CA%2BhUKGJ%2BoHhnvqjn3%3DHro7xu-YDR8FPr0FL6LF35kHRX%3D_bUzg%40mail.gmail.com

This use was not protecting any unportable code, it was just omitting
the code because it wouldn't be used.  Remove the use to reduce code
complexity a bit.

Discussion: https://www.postgresql.org/message-id/flat/54bde68c-d134-4eb8-5bd3-8af33b72a010@2ndquadrant.com

The previous system had configure put the value into the makefiles and
then have the makefiles pass them to the build of pg_config.  That was
put in place when pg_config was a shell script.  We can simplify that
by having configure put the value into pg_config.h directly.  This
also makes the standard build system match how the MSVC build system
already does it.

Discussion: https://www.postgresql.org/message-id/flat/6e457870-cef5-5f1d-b57c-fc89cfb8a788%402ndquadrant.com