No functional changes in this commit (except I could not resist the
temptation to re-word a couple of error messages).  This is just manual
cleanup after pgindent to make the code look reasonably like other PG
code, in preparation for more detailed code review to come.

Previously we waited for wal_writer_delay before flushing WAL. Now
we also wake WALWriter as soon as a WAL buffer page has filled.
Significant effect observed on performance of asynchronous commits
by Robert Haas, attributed to the ability to set hint bits on tuples
earlier and so reducing contention caused by clog lookups.

This seems to have been just an oversight in previous foreign-table work.
A quick grep didn't turn up any other places where RELKIND_FOREIGN_TABLE
was obviously omitted.

One change noted by Alexander Soudakov, the other by me.
Back-patch to 9.1.

This adds the "auto" option to the \x command, which switches to the
expanded mode when the normal output would be wider than the screen.

reviewed by Noah Misch

If it turns out we've locked the wrong OID, release the old lock.  In
most cases, it's pretty harmless to retain the extra lock, but this
seems tidier and avoids using lock table slots unnecessarily.

Per discussion with Tom Lane.

Report and patch by Josh Kupershmidt; comment revisions by me.

Previously, you'd get "function pg_catalog.pg_get_functiondef(integer) does
not exist", which is at best rather unprofessional-looking.  Back-patch
to 8.4 where \ef was introduced.

Josh Kupershmidt

This reverts commit 0180bd61.
contrib/userlock is gone, but user-level locking still exists,
and is exposed via the pg_advisory* family of functions.

If malloc(0) returns NULL, the binary search in findSecLabels() will
probably go into an infinite loop when there are no security labels,
because NULL-1 is greater than NULL after wraparound.

(We've seen this pathology before ... I wonder whether there's a way to
detect the class of bugs automatically?)

Diagnosis and patch by Steve Singer, cosmetic adjustments by me

Several server header files would not be installed in vpath builds
because they live in the build directory.

Backpatch to 9.1.

Mark Hills

I got alignment wrong in the redo routine. Spotted by redoing the log
genereated by copy regression test.

Forgot to call RestoreBkpBlocks() in the redo-function, as pointed out by
Simon Riggs. In redo of a regular heap insert, it's taken care of in
heap_redo(), but this new record type uses the heap2 RM, and heap2_redo()
does not take care of that for you.

Also, failed to reset the vmbuffer and all_visibile_cleared local variables
after switching to a new buffer.

It used to be cleaned in maintainer-clean, but that is inconsistent
with other cleaning of NLS files in nls-global.mk, and it's also wrong
overall, because it's not part of the distribution tarball, which is
the base definition of the maintainer-clean target.

This greatly reduces the WAL volume, especially when the table is narrow.
The overhead of locking the heap page is also reduced. Reduced WAL traffic
also makes it scale a lot better, if you run multiple COPY processes at
the same time.

Ensure that same index gets selected on 32-bit and 64-bit machines.
Per buildfarm results.

In particular, my previous patch expected the create_index test to run
before the inherit test; but this was only true in the serial schedule.
Rearrange this portion of the schedules to be more consistent.

Per buildfarm results.

Add PlaceHolderVar wrappers as needed to make UNION ALL sub-select output
expressions appear non-constant and distinct from each other.  This makes
the world safe for add_child_rel_equivalences to do what it does.  Before,
it was possible for that function to add identical expressions to different
EquivalenceClasses, which logically should imply merging such ECs, which
would be wrong; or to improperly add a constant to an EquivalenceClass,
drastically changing its behavior.  Per report from Teodor Sigaev.

The only currently known consequence of this bug is "MergeAppend child's
targetlist doesn't match MergeAppend" planner failures in 9.1 and later.
I am suspicious that there may be other failure modes that could affect
older release branches; but in the absence of any hard evidence, I'll
refrain from back-patching further than 9.1.

a new macro, DatumGetInetPP(), that does not. This brings these macros
in line with other DatumGet*P() macros.

Backpatch to 8.3, where 1-byte header varlenas were introduced.

Per an observation from Thom Brown that the old version contained a typo.

This was an oversight in commit b60653bc.

Also, fix a typo spotted by Thom Brown.

non_empty(anyrange) function was removed, empty(anyrange) was renamed to
isempty(anyrange), and !? operators were removed.

Since PostgreSQL 9.0, we've emitted a warning message when an operator
named => is created, because the SQL standard now reserves that token
for another use.  But we've also shipped such an operator with hstore.
Use of the function hstore(text, text) has been recommended in
preference to =>(text, text).  Per discussion, it's now time to take
the next step and stop shipping the operator.  This will allow us to
prohibit the use of => as an operator name in a future release if and
when we wish to support the SQL standard use of this token.

The release notes should mention this incompatibility.

Patch by me, reviewed by David Wheeler, Dimitri Fontaine and Tom Lane.

In a regular VACUUM, it's OK to skip pages for which a cleanup lock
isn't immediately available; the next VACUUM will deal with them.  If
we're scanning the entire relation to advance relfrozenxid, we might
need to wait, but only if there are tuples on the page that actually
require freezing.  These changes should greatly reduce the incidence
of of vacuum processes getting "stuck".

Simon Riggs and Robert Haas

Make it use t_isspace() to identify whitespace, rather than relying on
sscanf which is known to get it wrong on some platform/locale combinations.
Get rid of fixed-size buffers.  Make it actually continue to parse the file
after ignoring a line with untranslatable characters, as was obviously
intended.

The first of these issues is per gripe from J Smith, though not exactly
either of his proposed patches.

Further experimentation reveals that my previous change didn't fix the
issue entirely: these tests would still fail at the spring-forward DST
transition.  There doesn't seem to be any great value in testing this
specific issue for both timestamp and timestamptz, so just lose the
latter tests.

Adjust ill-considered timezone-dependent tests added in commit
8a3d33c8 so that they won't fail on DST
transition days.  Per all-pink buildfarm.

It was inadvertently changed to 201111111, which is a wrong date. Change it
to current date, and remove the comment that was supposed to remind me to
fix it before committing.

Noted by Tom