Guard against bad "dscale" values in numeric_recv().

We were not checking to see if the supplied dscale was valid for the given
digit array when receiving binary-format numeric values.  While dscale can
validly be more than the number of nonzero fractional digits, it shouldn't
be less; that case causes fractional digits to be hidden on display even
though they're there and participate in arithmetic.

Bug #12053 from Tommaso Sala indicates that there's at least one broken
client library out there that sometimes supplies an incorrect dscale value,
leading to strange behavior.  This suggests that simply throwing an error
might not be the best response; it would lead to failures in applications
that might seem to be working fine today.  What seems the least risky fix
is to truncate away any digits that would be hidden by dscale.  This
preserves the existing behavior in terms of what will be printed for the
transmitted value, while preventing subsequent arithmetic from producing
results inconsistent with that.

In passing, throw a specific error for the case of dscale being outside
the range that will fit into a numeric's header.  Before you got "value
overflows numeric format", which is a bit misleading.

Back-patch to all supported branches.
dummy_seclabel: add sql/, expected/, and .gitignores

Michael Paquier
pageinspect/BRIN: minor tweaks

Michael Paquier

Double-dash additions suggested by Peter Geoghegan
Minor cleanup of function declarations for BRIN.

Get rid of PG_FUNCTION_INFO_V1() macros, which are quite inappropriate
for built-in functions (possibly leftovers from testing as a loadable
module?).  Also, fix gratuitous inconsistency between SQL-level and
C-level names of the minmax support functions.
Fix JSON aggregates to work properly when final function is re-executed.

Davide S. reported that json_agg() sometimes produced multiple trailing
right brackets.  This turns out to be because json_agg_finalfn() attaches
the final right bracket, and was doing so by modifying the aggregate state
in-place.  That's verboten, though unfortunately it seems there's no way
for nodeAgg.c to check for such mistakes.

Fix that back to 9.3 where the broken code was introduced.  In 9.4 and
HEAD, likewise fix json_object_agg(), which had copied the erroneous logic.
Make some cosmetic cleanups as well.
Don't skip SQL backends in logical decoding for visibility computation.

The logical decoding patchset introduced PROC_IN_LOGICAL_DECODING flag
PGXACT flag, that allows such backends to be skipped when computing
the xmin horizon/snapshots. That's fine and sensible for walsenders
streaming out logical changes, but not at all fine for SQL backends
doing logical decoding. If the latter set that flag any change they
have performed outside of logical decoding will not be regarded as
visible - which e.g. can lead to that change being vacuumed away.

Note that not setting the flag for SQL backends isn't particularly
bothersome - the SQL backend doesn't do streaming, so it only runs for
a limited amount of time.

Per buildfarm member 'tick' and Alvaro.

Backpatch to 9.4, where logical decoding was introduced.
Improve error messages for malformed array input strings.

Make the error messages issued by array_in() uniformly follow the style
	ERROR: malformed array literal: "actual input string"
	DETAIL: specific complaint here
and rewrite many of the specific complaints to be clearer.

The immediate motivation for doing this is a complaint from Josh Berkus
that json_to_record() produced an unintelligible error message when
dealing with an array item, because it tries to feed the JSON-format
array value to array_in().  Really it ought to be smart enough to
perform JSON-to-Postgres array conversion, but that's a future feature
not a bug fix.  In the meantime, this change is something we agreed
we could back-patch into 9.4, and it should help de-confuse things a bit.
Install kludges to fix check-world for src/test/modules

check-world failed in a completely clean tree, because src/test/modules
fail to build unless errcodes.h is generated first.  To fix this,
install a dependency in src/test/modules' Makefile so that the necessary
file is generated.  Even with this, running "make check" within
individual module subdirs will still fail because the dependency is not
considered there, but this case is less interesting and would be messier
to fix.

check-world still failed with the above fix in place, this time because
dummy_seclabel used LOAD to load the dynamic library, which doesn't work
because the @libdir@ (expanded by the makefile) is expanded to the final
install path, not the temporary installation directory used by make
check.  To fix, tweak things so that CREATE EXTENSION can be used
instead, which solves the problem because the library path is expanded
by the backend, which is aware of the true libdir.
Fix whitespace
Fix typos
Keep track of transaction commit timestamps

Transactions can now set their commit timestamp directly as they commit,
or an external transaction commit timestamp can be fed from an outside
system using the new function TransactionTreeSetCommitTsData().  This
data is crash-safe, and truncated at Xid freeze point, same as pg_clog.

This module is disabled by default because it causes a performance hit,
but can be enabled in postgresql.conf requiring only a server restart.

A new test in src/test/modules is included.

Catalog version bumped due to the new subdirectory within PGDATA and a
couple of new SQL functions.

Authors: Álvaro Herrera and Petr Jelínek

Reviewed to varying degrees by Michael Paquier, Andres Freund, Robert
Haas, Amit Kapila, Fujii Masao, Jaime Casanova, Simon Riggs, Steven
Singer, Peter Eisentraut
doc: Fix markup

In the spirit of d34b48a021b181e30c53280d336820740f67570b

Per buildfarm member guaibasaurus, via Stefan Kaltenbrunner.
Move PG_AUTOCONF_FILENAME definition

Since this is not something that a user should change,
pg_config_manual.h was an inappropriate place for it.

In initdb.c, remove the use of the macro, because utils/guc.h can't be
included by non-backend code.  But we hardcode all the other
configuration file names there, so this isn't a disaster.
Fix SHLIB_PREREQS use in contrib, allowing PGXS builds

dblink and postgres_fdw use SHLIB_PREREQS = submake-libpq to build libpq
first.  This doesn't work in a PGXS build, because there is no libpq to
build.  So just omit setting SHLIB_PREREQS in this case.

Note that PGXS users can still use SHLIB_PREREQS (although it is not
documented).  The problem here is only that contrib modules can be built
in-tree or using PGXS, and the prerequisite is only applicable in the
former case.

Commit 6697aa2bc25c83b88d6165340348a31328c35de6 previously attempted to
address this by creating a somewhat fake submake-libpq target in
Makefile.global.  That was not the right fix, and it was also done in a
nonportable way, so revert that.
Remove USE_VPATH make variable from PGXS

The user can just set VPATH directly.  There is no need to invent
another variable.
Revert haphazard pgxs makefile changes

These changes were originally submitted as "adds support for VPATH with
USE_PGXS", but they are not necessary for VPATH support, so they just
add more lines of code for no reason.
Fix PGXS vpath build when PostgreSQL is built with vpath

PGXS computes srcdir from VPATH, PostgreSQL proper computes VPATH from
srcdir, and doing both results in an error from make.  Conditionalize so
only one of these takes effect.
Document that pg_stat_*_tables.n_tup_upd includes n_tup_hot_upd.

Author: Peter Geoghegan
Don't dump core if pq_comm_reset() is called before pq_init().

This can happen if an error occurs in a standalone backend.  This bug
was introduced by commit 2bd9e412f92bc6a68f3e8bcb18e04955cc35001d.

Reported by Álvaro Herrera.
Fix pg_xlogdump's calculation of full-page image data.

The old formula was completely bogus with the new WAL record format.