Translation updates
Rename pg_recvlogical's --create/--drop to --create-slot/--drop-slot.

A future patch (9.5 only) adds slot management to pg_receivexlog. The
verbs create/drop don't seem descriptive enough there. It seems better
to rename pg_recvlogical's commands now, in beta, than live with the
inconsistency forever.

The old form (e.g. --drop) will still be accepted by virtue of most
getopt_long() options accepting abbreviations for long commands.

Backpatch to 9.4 where pg_recvlogical was introduced.

Author: Michael Paquier and Andres Freund
Discussion: CAB7nPqQtt79U6FmhwvgqJmNyWcVCbbV-nS72j_jyPEopERg9rg@mail.gmail.com
Add support for managing physical replication slots to pg_receivexlog.

pg_receivexlog already has the capability to use a replication slot to
reserve WAL on the upstream node. But the used slot currently has to
be created via SQL.

To allow using slots directly, without involving SQL, add
--create-slot and --drop-slot actions, analogous to the logical slot
manipulation support in pg_recvlogical.

Author: Michael Paquier
Discussion: CABUevEx+zrOHZOQg+dPapNPFRJdsk59b=TSVf30Z71GnFXhQaw@mail.gmail.com
Clean up Create/DropReplicationSlot query buffer

CreateReplicationSlot() and DropReplicationSlot() were not cleaning up
the query buffer in some cases (mostly error conditions) which meant a
small leak.  Not generally an issue as the error case would result in an
immediate exit, but not difficult to fix either and reduces the number
of false positives from code analyzers.

In passing, also add appropriate PQclear() calls to RunIdentifySystem().

Pointed out by Coverity.
Fix array overrun in ecpg's version of ParseDateTime().

The code wrote a value into the caller's field[] array before checking
to see if there was room, which of course is backwards.  Per report from
Michael Paquier.

I fixed the equivalent bug in the backend's version of this code way back
in 630684d3a130bb93, but failed to think about ecpg's copy.  Fortunately
this doesn't look like it would be exploitable for anything worse than a
core dump: an external attacker would have no control over the single word
that gets written.
Fix typo in elog message.
Implement SKIP LOCKED for row-level locks

This clause changes the behavior of SELECT locking clauses in the
presence of locked rows: instead of causing a process to block waiting
for the locks held by other processes (or raise an error, with NOWAIT),
SKIP LOCKED makes the new reader skip over such rows.  While this is not
appropriate behavior for general purposes, there are some cases in which
it is useful, such as queue-like tables.

Catalog version bumped because this patch changes the representation of
stored rules.

Reviewed by Craig Ringer (based on a previous attempt at an
implementation by Simon Riggs, who also provided input on the syntax
used in the current patch), David Rowley, and Álvaro Herrera.

Author: Thomas Munro
Extend shm_mq API with new functions shm_mq_sendv, shm_mq_set_handle.

shm_mq_sendv sends a message to the queue assembled from multiple
locations.  This is expected to be used by forthcoming patches to
allow frontend/backend protocol messages to be sent via shm_mq, but
might be useful for other purposes as well.

shm_mq_set_handle associates a BackgroundWorkerHandle with an
already-existing shm_mq_handle.  This solves a timing problem when
creating a shm_mq to communicate with a newly-launched background
worker: if you attach to the queue first, and the background worker
fails to start, you might block forever trying to do I/O on the queue;
but if you start the background worker first, but then die before
attaching to the queue, the background worrker might block forever
trying to do I/O on the queue.  This lets you attach before starting
the worker (so that the worker is protected) and then associate the
BackgroundWorkerHandle later (so that you are also protected).

Patch by me, reviewed by Stephen Frost.
Split builtins.h to a new header ruleutils.h

The new header contains many prototypes for functions in ruleutils.c
that are not exposed to the SQL level.

Reviewed by Andres Freund and Michael Paquier.
Fix broken example in PL/pgSQL document.

Back-patch to all supported branches.

Marti Raudsepp, per a report from Marko Tiikkaja
Change the way encoding and locale checks are done in pg_upgrade.

Lc_collate and lc_ctype have been per-database settings since server version
8.4, but pg_upgrade was still treating them as cluster-wide options. It
fetched the values for the template0 databases in old and new cluster, and
compared them. That's backwards; the encoding and locale of the template0
database doesn't matter, as template0 is guaranteed to contain only ASCII
characters. But if there are any other databases that exist on both clusters
(in particular template1 and postgres databases), their encodings and
locales must be compatible.

Also, make the locale comparison more lenient. If the locale names are not
equal, try to canonicalize both of them by passing them to setlocale(). We
used to do that only when upgrading from 9.1 or below, but it seems like a
good idea even with newer versions. If we change the canonical form of a
locale, this allows pg_upgrade to still work. I'm about to do just that to
fix bug #11431, by mapping a locale name that contains non-ASCII characters
to a pure-ASCII alias of the same locale.

No backpatching, because earlier versions of pg_upgrade still support
upgrading from 8.3 servers. That would be more complicated, so it doesn't
seem worth it, given that we haven't received any complaints about this
from users.
Remove unnecessary initialization of local variables.

Oops, forgot these in the prveious commit.
Fix bogus optimization in JSONB containment tests.

When determining whether one JSONB object contains another, it's okay to
make a quick exit if the first object has fewer pairs than the second:
because we de-duplicate keys within objects, it is impossible that the
first object has all the keys the second does.  However, the code was
applying this rule to JSONB arrays as well, where it does *not* hold
because arrays can contain duplicate entries.  The test was really in
the wrong place anyway; we should do it within JsonbDeepContains, where
it can be applied to nested objects not only top-level ones.

Report and test cases by Alexander Korotkov; fix by Peter Geoghegan and
Tom Lane.
Improve documentation about JSONB array containment behavior.

Per gripe from Josh Berkus.
regression:  adjust polygon diagrams to not use tabs

Also, small diagram adjustments

Patch by Emre Hasegeli
docs:  remove mention that attnotnull should be changed

Report by Andres Freund
pg_upgrade:  prefix Unix shell script name output with "./"

This more clearly suggests the current directory.  While this also works
on Windows, it might be confusing.

Report by Christoph Berg
Message improvements
pg_recvlogical: Improve --help output

List the actions first, as they are the most important options.  Group
the other options more sensibly, consistent with the man page.  Correct
a few typographical errors, clarify some things.

Also update the pg_receivexlog --help output to make it a bit more
consistent with that of pg_recvlogical.
Suppress dead, unportable src/port/crypt.c code.

This file used __int64, which is specific to native Windows, rather than
int64.  Suppress the long-unused union field of this type.  Noticed on
Cygwin x86_64 with -lcrypt not installed.  Back-patch to 9.0 (all
supported versions).