Un-break peer authentication.

Commit 613c6d26bd42dd8c2dd0664315be9551475b8864 sloppily replaced a
lookup of the UID obtained from getpeereid() with a lookup of the
server's own user name, thus totally destroying peer authentication.
Revert.  Per report from Christoph Berg.

In passing, make sure get_user_name() zeroes *errstr on success on
Windows as well as non-Windows.  I don't think any callers actually
depend on this ATM, but we should be consistent across platforms.
Fix EquivalenceClass processing for nested append relations.

The original coding of EquivalenceClasses didn't foresee that appendrel
child relations might themselves be appendrels; but this is possible for
example when a UNION ALL subquery scans a table with inheritance children.
The oversight led to failure to optimize ordering-related issues very well
for the grandchild tables.  After some false starts involving explicitly
flattening the appendrel representation, we found that this could be fixed
easily by removing a few implicit assumptions about appendrel parent rels
not being children themselves.

Kyotaro Horiguchi and Tom Lane, reviewed by Noah Misch
Adjust getpwuid() fix commit to display errno string on failure

This adjusts patch 613c6d26bd42dd8c2dd0664315be9551475b8864.
Improve regression test for pg_filenode_relation().

Make it print the details in case there's a failure.

Andres Freund, slightly modified by me
Force consistent row order in contrib/test_decoding regression test.
Document platform-specificity of unix_socket_permissions.

Back-patch to 8.4 (all supported versions).
Secure Unix-domain sockets of "make check" temporary clusters.

Any OS user able to access the socket can connect as the bootstrap
superuser and in turn execute arbitrary code as the OS user running the
test.  Protect against that by placing the socket in the temporary data
directory, which has mode 0700 thanks to initdb.  Back-patch to 8.4 (all
supported versions).  The hazard remains wherever the temporary cluster
accepts TCP connections, notably on Windows.

Attempts to run "make check" from a directory with a long name will now
fail.  An alternative not sharing that problem was to place the socket
in a subdirectory of /tmp, but that is only secure if /tmp is sticky.
The PG_REGRESS_SOCK_DIR environment variable is available as a
workaround when testing from long directory paths.

As a convenient side effect, this lets testing proceed smoothly in
builds that override DEFAULT_PGSOCKET_DIR.  Popular non-default values
like /var/run/postgresql are often unwritable to the build user.

Security: CVE-2014-0067
Revert "Secure Unix-domain sockets of "make check" temporary clusters."

About half of the buildfarm members use too-long directory names,
strongly suggesting that this approach is a dead end.
Fix dumping of a materialized view that depends on a table's primary key.

It is possible for a view or materialized view to depend on a table's
primary key, if the view query relies on functional dependency to
abbreviate a GROUP BY list.  This is problematic for pg_dump since we
ordinarily want to dump view definitions in the pre-data section but
indexes in post-data.  pg_dump knows how to deal with this situation for
regular views, by breaking the view's ON SELECT rule apart from the view
proper.  But it had not been taught what to do about materialized views,
and in fact mistakenly dumped them as regular views in such cases, as
seen in bug #9616 from Jesse Denardo.

If we had CREATE OR REPLACE MATERIALIZED VIEW, we could fix this in a
manner analogous to what's done for regular views; but we don't yet,
and we'd not back-patch such a thing into 9.3 anyway.  As a hopefully-
temporary workaround, break the circularity by postponing the matview
into post-data altogether when this case occurs.
psql:  display "Replica Identity" only for FULL and NOTHING

INDEX is already displayed on the index, and we now exclude pg_catalog.
DEFAULT is not displayed.
Use separate output dirs for test_decoding's two runs.

contrib/test_decoding's "make check" runs two sets of tests. Unless we
specify separate output directories for each set the isolation tests
will overwrite the output from the  normal regression set. Doing this
will help the buildfarm collect complete logs.
Rename GinLogicValue to GinTernaryValue.

It's more descriptive. Also, get rid of the enum, and use #defines instead,
per Greg Stark's suggestion.
Rewrite the way GIN posting lists are packed on a page, to reduce WAL volume.

Inserting (in retail) into the new 9.4 format GIN posting tree created much
larger WAL records than in 9.3. The previous strategy to WAL logging was
basically to log the whole page on each change, with the exception of
completely unmodified segments up to the first modified one. That was not
too bad when appending to the end of the page, as only the last segment had
to be WAL-logged, but per Fujii Masao's testing, even that produced 2x the
WAL volume that 9.3 did.

The new strategy is to keep track of changes to the posting lists in a more
fine-grained fashion, and also make the repacking" code smarter to avoid
decoding and re-encoding segments unnecessarily.
Fix thinko in logical decoding code.

Andres Freund
Count buffers dirtied due to hints in pgBufferUsage.shared_blks_dirtied.

Previously, such buffers weren't counted, with the possible result that
EXPLAIN (BUFFERS) and pg_stat_statements would understate the true
number of blocks dirtied by an SQL statement.

Back-patch to 9.2, where this counter was introduced.

Amit Kapila
test_decoding: Update .gitignore

Commit 7317d8d961f210c3a6b20972cd605bcd9bffb06e changed the set of
things that need to be ignored, but neglected to update .gitignore.
Mark FastPathStrongRelationLocks volatile.

Otherwise, the compiler might decide to move modifications to data
within this structure outside the enclosing SpinLockAcquire /
SpinLockRelease pair, leading to shared memory corruption.

This may or may not explain a recent lmgr-related buildfarm failure
on prairiedog, but it needs to be fixed either way.
Fix typo in comment.

Amit Langote
Move SizeOfHeapNewCid next to xl_heap_new_cid struct.

They belong together, but the xl_heap_rewrite_mapping struct was wedged
in between.
Fix bug in the new B-tree incomplete-split code.

Inserting a downlink to an internal page clears the incomplete-split flag
of the child's left sibling, so the left sibling's LSN also needs to be
updated.