such as debugging and performance measurement.  This consists of two features:
a table of "rendezvous variables" that allows separately-loaded shared
libraries to communicate, and a new GUC setting "local_preload_libraries"
that allows libraries to be loaded into specific sessions without explicit
cooperation from the client application.  To make local_preload_libraries
as flexible as possible, we do not restrict its use to superusers; instead,
it is restricted to load only libraries stored in $libdir/plugins/.  The
existing LOAD command has also been modified to allow non-superusers to
LOAD libraries stored in this directory.

This patch also renames the existing GUC variable preload_libraries to
shared_preload_libraries (after a suggestion by Simon Riggs) and does some
code refactoring in dfmgr.c to improve clarity.

Korry Douglas, with a little help from Tom Lane.

patches contributed by Itagaki Takahiro.

Fixed broken newline on Windows.
Fixed a nasty buffer underrun that only occured when using Informix
no_indicator NULL setting on timestamps and intervals.

requiring read permissions.  Up till now there was no possible case
in which the RTEs wouldn't already have ACL_SELECT set ... but now that
you can say something like 'INSERT INTO foo ... RETURNING *' this is
an essential step.  With this commit, a RETURNING clause adds the
requirement for SELECT permissions on the target table if and only if
the clause actually reads the value of at least one target-table column.

cannot assume that there's exactly one Query in the Portal, as we can for
ONE_SELECT mode, because non-SELECT queries might have extra queries added
during rule rewrites.  Fix things up so that we'll use ONE_RETURNING mode
when a Portal contains one primary (canSetTag) query and that query has
a RETURNING list.  This appears to be a second showstopper reason for running
the Portal to completion before we start to hand anything back --- we want
to be sure that the rule-added queries get run too.

as per yesterday's proposal.  Also make things a tad more orthogonal by
adding the recent STRICT addition to EXECUTE INTO.
Jonah Harris and Tom Lane

_SPI_execute_plan's return code should reflect the type of the query
that is marked canSetTag, not necessarily the last one in the list.

This is arguably a bug fix, but I'm hesitant to back-patch it because
it's the sort of subtle change that might break someone's code, and it's
best not to do that kind of thing in point releases.

a Coverity warning, these are risky since the hashtable isn't necessarily
fully set up yet.  They're unnecessary anyway: a deletable hashtable
should be in a memory context that will be cleared following elog(ERROR).
Per report from Martijn van Oosterhout.

values, due to concern about the patch.

and instead make the grammar production for the RETURN statement do the
heavy lifting.  The lookahead idea was copied from the main parser, but
it does not work in plpgsql's parser because here gram.y looks explicitly
at the scanner's yytext variable, which will be out of sync after a
failed lookahead step.  A minimal example is

create or replace function foo() returns void language plpgsql as '
begin
  perform return foo bar;
end';

which can be seen by testing to deliver "foo foo bar" to the main parser
instead of the expected "return foo bar".  This isn't a huge bug since
RETURN is not found in the main grammar, but it could bite someone who
tried to use "return" as an identifier.

Back-patch to 8.1.  Bug exists further back, but HEAD patch doesn't apply
cleanly, and given the lack of field complaints it doesn't seem worth
the effort to develop adjusted patches.

when what's being executed is a COMMIT or ROLLBACK.  Per report from
Sergey Koposov.  Backpatch to 8.1; 8.0 and before don't have the bug
due to lack of any logging at all here.

for INSERT/UPDATE/DELETE RETURNING.  Per discussion.

so that it won't interfere with later trials.  Per recent buildfarm
experience.  Anyone know how to do this on Windows?

well as vacuum_cost_delay.  Since datestyle is a string variable,
this exercises memory allocation issues that might not appear when
modifying an integer GUC variable.  Also, we can observe the side
effects of changing datestyle to check that assign hooks are called
at the right times.

nonunique join value, leading to plan-choice-dependent results ... and
it seems some platforms will choose a different plan.  Tweak the test
so that it has well-defined results.  Per report from Olivier Prenant.

Merged dyntest.pgc and dyntest2.pgc.
Hopefully fixed the last Coverity reports (finally)

hash and array variables.  (regression output updated)

default values.

merely a matter of fixing the error check, since the underlying Portal
infrastructure already handles it.  This in turn allows these statements
to be used in some existing plpgsql and plperl contexts, such as a
plpgsql FOR loop.  Also, do some marginal code cleanup in places that
were being sloppy about distinguishing SELECT from SELECT INTO.

hashes.  Was causing regression failures.

failures.

default values.  Was causing regression failures.

< 	o Allow INSERT/UPDATE ... RETURNING new.col or old.col
<
< 	  This is useful for returning the auto-generated key for an INSERT.
< 	  One complication is how to handle rules that run as part of
< 	  the insert.
< 	  http://archives.postgresql.org/pgsql-patches/2005-07/msg00568.php
> 	o -Allow INSERT/UPDATE ... RETURNING new.col or old.col

plpgsql support to come later.  Along the way, convert execMain's
SELECT INTO support into a DestReceiver, in order to eliminate some ugly
special cases.

Jonah Harris and Tom Lane

Yoshiyuki Asaba

< 	o %Allow commenting of variables in postgresql.conf to restore them
> 	o -Allow commenting of variables in postgresql.conf to restore them

defaults.

Zdenek Kotala

The main reason for refactoring was that set_config_option() was too
overloaded function and its behavior did not consistent. Old version of
set_config_function hides some messages. For example if you type:

tcp_port = 5432.1

then old implementation ignore this error without any message to log
file in the signal context (configuration reload). Main problem was that
semantic analysis of postgresql.conf is not perform in the
ProcessConfigFile function, but in the set_config_options *after*
context check. This skipped check for variables with PG_POSTMASTER
context. There was request from Joachim Wieland to add more messages
about ignored changes in the config file as well.

Zdenek Kotala

Allow conversion from perl to postgresql array in OUT parameters. Second,
allow hash form output from procedures with one OUT argument.

Pavel Stehule

David Fetter