Follow the RFCs more closely in libpq server certificate hostname check.

The RFCs say that the CN must not be checked if a subjectAltName extension
of type dNSName is present. IOW, if subjectAltName extension is present,
but there are no dNSNames, we can still check the CN.

Alexey Klyukin
Fix the return type of GIN triConsistent support functions to "char".

They were marked to return a boolean, but they actually return a
GinTernaryValue, which is more like a "char". It makes no practical
difference, as the triConsistent functions cannot be called directly from
SQL because they have "internal" arguments, but this nevertheless seems
more correct.

Also fix the GinTernaryValue name in the documentation. I renamed the enum
earlier, but neglected the docs.

Alexander Korotkov. This is new in 9.4, so backpatch there.
Fix TAP checks when current directory name contains spaces

Add some quotes in the makefile snippet that creates the temporary
installation, so that it can handle spaces in the directory name and
possibly some other oddities.
Fix configure check for %z printf support after INT64_MODIFIER changes.

The PGAC_FUNC_SNPRINTF_SIZE_T_SUPPORT test was broken by
ce486056ecd28050. Among others it made the UINT64_FORMAT macro to be
defined in c.h, instead of directly being defined by configure.

This lead to the replacement printf being used on all platforms for a
while. Which seems to work, because this was only used due to
different profiles ;)

Fix by relying on INT64_MODIFIER instead.
Add rmgr callback to name xlog record types for display purposes.

This is primarily useful for the upcoming pg_xlogdump --stats feature,
but also allows to remove some duplicated code in the rmgr_desc
routines.

Due to the separation and harmonization, the output of dipsplayed
records changes somewhat. But since this isn't enduser oriented
content that's ok.

It's potentially desirable to further change pg_xlogdump's display of
records. It previously wasn't possible to show the record type
separately from the description forcing it to be in the last
column. But that's better done in a separate commit.

Author: Abhijit Menon-Sen, slightly editorialized by me
Reviewed-By: Álvaro Herrera, Andres Freund, and Heikki Linnakangas
Discussion: 20140604104716.GA3989@toroid.org
Add the capability to display summary statistics to pg_xlogdump.

The new --stats/--stats=record options to pg_xlogdump display per
rmgr/per record statistics about the parsed WAL. This is useful to
understand what the WAL primarily consists of, to allow targeted
optimizations on application, configuration, and core code level.

It is likely that we will want to fine tune the statistics further,
but the feature already is quite helpful.

Author: Abhijit Menon-Sen, slightly editorialized by me
Reviewed-By: Andres Freund, Dilip Kumar and Furuya Osamu
Discussion: 20140604104716.GA3989@toroid.org
Avoid 'clobbered by longjmp' warning in psql/copy.c.

This was introduced in 51bb79569f934ad2135c2ff859c61b9ab8d51750.
Mark x86's memory barrier inline assembly as clobbering the cpu flags.

x86's memory barrier assembly was marked as clobbering "memory" but
not "cc" even though 'addl' sets various flags. As it turns out gcc on
x86 implicitly assumes "cc" on every inline assembler statement, so
it's not a bug. But as that's poorly documented and might get copied
to architectures or compilers where that's not the case, it seems
better to be precise.

Discussion: 20140919100016.GH4277@alap3.anarazel.de

To keep the code common, backpatch to 9.2 where explicit memory
barriers were introduced.
Row-Level Security Policies (RLS)

Building on the updatable security-barrier views work, add the
ability to define policies on tables to limit the set of rows
which are returned from a query and which are allowed to be added
to a table.  Expressions defined by the policy for filtering are
added to the security barrier quals of the query, while expressions
defined to check records being added to a table are added to the
with-check options of the query.

New top-level commands are CREATE/ALTER/DROP POLICY and are
controlled by the table owner.  Row Security is able to be enabled
and disabled by the owner on a per-table basis using
ALTER TABLE .. ENABLE/DISABLE ROW SECURITY.

Per discussion, ROW SECURITY is disabled on tables by default and
must be enabled for policies on the table to be used.  If no
policies exist on a table with ROW SECURITY enabled, a default-deny
policy is used and no records will be visible.

By default, row security is applied at all times except for the
table owner and the superuser.  A new GUC, row_security, is added
which can be set to ON, OFF, or FORCE.  When set to FORCE, row
security will be applied even for the table owner and superusers.
When set to OFF, row security will be disabled when allowed and an
error will be thrown if the user does not have rights to bypass row
security.

Per discussion, pg_dump sets row_security = OFF by default to ensure
that exports and backups will have all data in the table or will
error if there are insufficient privileges to bypass row security.
A new option has been added to pg_dump, --enable-row-security, to
ask pg_dump to export with row security enabled.

A new role capability, BYPASSRLS, which can only be set by the
superuser, is added to allow other users to be able to bypass row
security using row_security = OFF.

Many thanks to the various individuals who have helped with the
design, particularly Robert Haas for his feedback.

Authors include Craig Ringer, KaiGai Kohei, Adam Brightwell, Dean
Rasheed, with additional changes and rework by me.

Reviewers have included all of the above, Greg Smith,
Jeff McCormick, and Robert Haas.
Add a fast pre-check for equality of equal-length strings.

Testing reveals that that doing a memcmp() before the strcoll() costs
practically nothing, at least on the systems we tested, and it speeds
up sorts containing many equal strings significatly.

Peter Geoghegan.  Review by myself and Heikki Linnakangas.  Comments
rewritten by me.
doc: Use <literal> and all-caps for READ COMMITTED isolation level.

The documentation overall is not entirely consistent about how we do
this, but this is consistent with other usages within lock.sgml.

Etsuro Fujita
Fix failure of contrib/auto_explain to print per-node timing information.

This has been broken since commit af7914c6627bcf0b0ca614e9ce95d3f8056602bf,
which added the EXPLAIN (TIMING) option.  Although that commit included
updates to auto_explain, they evidently weren't tested very carefully,
because the code failed to print node timings even when it should, due to
failure to set es.timing in the ExplainState struct.  Reported off-list by
Neelakanth Nadgir of Salesforce.

In passing, clean up the documentation for auto_explain's options a
little bit, including re-ordering them into what seems to me a more
logical order.
Improve code around the recently added rm_identify rmgr callback.

There are four weaknesses in728f152e07f998d2cb4fe5f24ec8da2c3bda98f2:

* append_init() in heapdesc.c was ugly and required that rm_identify
  return values are only valid till the next call. Instead just add a
  couple more switch() cases for the INIT_PAGE cases. Now the returned
  value will always be valid.
* a couple rm_identify() callbacks missed masking xl_info with
  ~XLR_INFO_MASK.
* pg_xlogdump didn't map a NULL rm_identify to UNKNOWN or a similar
  string.
* append_init() was called when id=NULL - which should never actually
  happen. But it's better to be careful.
Remove postgres --help blurb about the removed -A option.

I missed this in 3bdcf6a5a755503.

Noticed by Merlin Moncure
Discussion: CAHyXU0yC7uPeeVzQROwtnrOP9dxTEUPYjB0og4qUnbipMEV57w@mail.gmail.com
Fix mishandling of CreateEventTrigStmt's eventname field.

It's a string, not a scalar.

Petr Jelinek
Fix compiler warning.

It is meaningless to declare a pass-by-value return type const.
Remove volatile qualifiers from lwlock.c.

Now that spinlocks (hopefully!) act as compiler barriers, as of commit
0709b7ee72e4bc71ad07b7120acd117265ab51d0, this should be safe.  This
serves as a demonstration of the new coding style, and may be optimized
better on some machines as well.
Remove most volatile qualifiers from xlog.c

For the reason outlined in df4077cda2e also remove volatile qualifiers
from xlog.c. Some of these uses of volatile have been added after
noticing problems back when spinlocks didn't imply compiler
barriers. So they are a good test - in fact removing the volatiles
breaks when done without the barriers in spinlocks present.

Several uses of volatile remain where they are explicitly used to
access shared memory without locks. These locations are ok with
slightly out of date data, but removing the volatile might lead to the
variables never being reread from memory. These uses could also be
replaced by barriers, but that's a separate change of doubtful value.
Process withCheckOption exprs in setrefs.c

While withCheckOption exprs had been handled in many cases by
happenstance, they need to be handled during set_plan_references and
more specifically down in set_plan_refs for ModifyTable plan nodes.
This is to ensure that the opfuncid's are set for operators referenced
in the withCheckOption exprs.

Identified as an issue by Thom Brown

Patch by Dean Rasheed

Back-patch to 9.4, where withCheckOption was introduced.
Log ALTER SYSTEM statements as DDL

Per discussion in bug #11350, log ALTER SYSTEM commands at the
log_statement=ddl level, rather than at the log_statement=all level.

Pointed out by Tomonari Katsumata.

Back-patch to 9.4 where ALTER SYSTEM was introduced.