Avoid repeated creation/freeing of per-subre DFAs during regex search.

In nested sub-regex trees, lower-level nodes created DFAs and then
destroyed them again before exiting, which is a bit dumb considering that
the recursive search is likely to call those nodes again later.  Instead
cache each created DFA until the end of pg_regexec().  This is basically a
space for time tradeoff, in that it might increase the maximum memory
usage.  However, in most regex patterns there are not all that many subre
nodes, so not that many DFAs --- and in any case, the peak usage occurs
when reaching the bottom recursion level, and except for alternation cases
that's going to be the same anyway.
Merge dissect() into cdissect() to remove a pile of near-duplicate code.

The "uncomplicated" case isn't materially less complicated than the full
case, certainly not enough so to justify duplicating nearly 500 lines
of code.  The only extra work being done in the full path is zaptreesubs,
which is very cheap compared to everything else being done here, and
besides that I'm less than convinced that it's not needed in some cases
even without backrefs.
Make each pg_stat_ view into it's own table in the documentation

This makes it easier to match a column name with the description of it,
and makes it possible to add more detailed documentation in the future.

This patch does not add that extra documentation at this point, only
the structure required for it.

Modeled on the changes already done to pg_stat_activity.
Merge the list of statistics functions into the view documentation

Most people won't read them individually anyway, it's an easy way to find
them, and it's a lot of duplicated information if they are kept in two
different places.
Fix some typos and correct wording in the monitoring docs patch

Thom Brown
Remove useless const qualifier

Claiming that the typevar argument to DefineCompositeType() is const
was a plain lie.  A similar case in DefineVirtualRelation() was
already changed in passing in commit 1575fbcb.  Also clean up the now
unnecessary casts that used to cast away the const.
Remove useless cast
Fix some more bugs in GIN's WAL replay logic.

In commit 4016bdef8aded77b4903c457050622a5a1815c16 I fixed a bunch of
ginxlog.c bugs having to do with not handling XLogReadBuffer failures
correctly.  However, in ginRedoUpdateMetapage and ginRedoDeleteListPages,
I unaccountably thought that failure to read the metapage would be
impossible and just put in an elog(PANIC) call.  This is of course wrong:
failure is exactly what will happen if the index got dropped (or rebuilt)
between creation of the WAL record and the crash we're trying to recover
from.  I believe this explains Nicholas Wilson's recent report of these
errors getting reached.

Also, fix memory leak in forgetIncompleteSplit.  This wasn't of much
concern when the code was written, but in a long-running standby server
page split records could be expected to accumulate indefinitely.

Back-patch to 8.4 --- before that, GIN didn't have a metapage.
Call check_keywords.pl in maintainer-check

For that purpose, have check_keywords.pl print errors to stderr and
return a useful exit status.
ALTER TABLE: skip FK validation when it's safe to do so

We already skip rewriting the table in these cases, but we still force a
whole table scan to validate the data.  This can be skipped, and thus
we can make the whole ALTER TABLE operation just do some catalog touches
instead of scanning the table, when these two conditions hold:

(a) Old and new pg_constraint.conpfeqop match exactly.  This is actually
stronger than needed; we could loosen things by way of operator
families, but it'd require a lot more effort.

(b) The functions, if any, implementing a cast from the foreign type to
the primary opcintype are the same.  For this purpose, we can consider a
binary coercion equivalent to an exact type match.  When the opcintype
is polymorphic, require that the old and new foreign types match
exactly.  (Since ri_triggers.c does use the executor, the stronger check
for polymorphic types is no mere future-proofing.  However, no core type
exercises its necessity.)

Author: Noah Misch

Committer's note: catalog version bumped due to change of the Constraint
node.  I can't actually find any way to have such a node in a stored
rule, but given that we have "out" support for them, better be safe.
psql: when tab-completing, use quotes on file names that need them

psql backslash commands that deal with file or directory names require
quotes around those that have spaces, single quotes, or backslashes.
However, tab-completing such names does not provide said quotes, and is
thus almost useless with them.

This patch fixes the problem by having a wrapper function around
rl_filename_completion_function that dequotes on input and quotes on
output.  This eases dealing with such names.

Author: Noah Misch
Add const qualifiers where they are accidentally cast away

This only produces warnings under -Wcast-qual, but it's more correct
and consistent in any case.
Fix thinko in new match_join_clauses_to_index() logic.

We don't need to constrain the other side of an indexable join clause to
not be below an outer join; an example here is

SELECT FROM t1 LEFT JOIN t2 ON t1.a = t2.b LEFT JOIN t3 ON t2.c = t3.d;

We can consider an inner indexscan on t3.d using c = d as indexqual, even
though t2.c is potentially nulled by a previous outer join.  The comparable
logic in orindxpath.c has always worked that way, but I was being overly
cautious here.
Move CRC tables to libpgport, and provide them in a separate include file.

This makes it much more convenient to build tools for Postgres that are
separately compiled and require a matching CRC implementation.

To prevent multiple copies of the CRC polynomial tables being introduced
into the postgres binaries, they are now included in the static library
libpgport that is mainly meant for replacement system functions.  That
seems like a bit of a kludge, but there's no better place.

This cleans up building of the tools pg_controldata and pg_resetxlog,
which previously had to build their own copies of pg_crc.o.

In the future, external programs that need access to the CRC tables can
include the tables directly from the new header file pg_crc_tables.h.

Daniel Farina, reviewed by Abhijit Menon-Sen and Tom Lane
Fix typo in comment

Haifeng Liu
Fix MSVC builds for previous patch's addition of a src/port file.

(And why in the world is this OBJS list not being scraped from the
corresponding Makefile?)
Correctly detect SSI conflicts of prepared transactions after crash.

A prepared transaction can get new conflicts in and out after preparing, so
we cannot rely on the in- and out-flags stored in the statefile at prepare-
time. As a quick fix, make the conservative assumption that after a restart,
all prepared transactions are considered to have both in- and out-conflicts.
That can lead to unnecessary rollbacks after a crash, but that shouldn't be
a big problem in practice; you don't want prepared transactions to hang
around for a long time anyway.

Dan Ports
Simplify references to backslash-doubling in func.sgml.

Several places were still written as though standard_conforming_strings
didn't exist, much less be the default.  Now that it is on by default,
we can simplify the text and just insert occasional notes suggesting that
you might have to think harder if it's turned off.  Per discussion of a
suggestion from Hannes Frederic Sowa.

Back-patch to 9.1 where standard_conforming_strings was made the default.
Remove TOAST table from pg_database

The only toastable column now is datacl, but we don't really support
long ACLs anyway.  The TOAST table should have been removed when the
pg_db_role_setting catalog was introduced in commit
2eda8dfb52ed9962920282d8384da8bb4c22514d, but I forgot to do that.

Per -hackers discussion on March 2011.
psql: Improve error display for psql -f -

Running "psql -f -" used to print

psql:<stdin>:1: ERROR:  blah

but that got broken between 8.4 and 9.0 (commit
b291c0fba83a1e93868e2f69c03be195d620f30c), and now it printed

psql:-:1: ERROR:  blah

This reverts to the old behavior and cleans up some code that was left
dead or useless by the mentioned commit.