spoofing when the socket file has been moved.

> * Improve deadlock detection when deleting items from shared buffers
>
>   http://archives.postgresql.org/pgsql-bugs/2008-01/msg00138.php
>   http://archives.postgresql.org/pgsql-hackers/2008-01/msg00873.php
>   http://archives.postgresql.org/pgsql-committers/2008-01/msg00365.php

Should fix a problem where two clusters are running under
two different service accounts and get colliding names,
causing only the first cluster to contain the pgident
event description.

Per report from Stephen Denne.

Keep the intermediate symbol file rather then blowing it away, for easier debugging.

operations when the current transaction has any open references to the
target relation or index (implying it has an active query using the relation).
The need for this was previously recognized in connection with ALTER TABLE,
but anything that summarily eliminates tuples or moves them around would
confuse an active scan.

While this patch does not in itself fix bug #3883 (the deadlock would happen
before the new check fires), it will discourage people from attempting the
sequence of operations that creates a deadlock risk, so it's at least a
partial response to that problem.

In passing, add a previously-missing check to REINDEX to prevent trying to
reindex another backend's temp table.  This isn't a security problem since
only a superuser would get past the schema permission checks, but if we are
testing for this in other utility commands then surely REINDEX should too.

synchronized-scanning behavior, and make pg_dump disable sync scans so that
it will reliably preserve row ordering.  Per recent discussions.

soon.  I suspect this explains bug #3902, though I'm still not able to
reproduce that.

< * Add anonymous transactions
> * Add autonomous transactions

> * Add anonymous transactions
>
>   http://archives.postgresql.org/pgsql-hackers/2008-01/msg00893.php
>

< 	  o Allow the PITR process to be debugged and data examined

from Gevik Babakhani

the patch for those features put its cleanup code into freePGconn() which is
really the wrong place.  Remove redundant code from freePGconn() and add
comments in hopes of preventing similar mistakes in future.
Noticed while trying (futilely) to reproduce bug #3902.

are known to write on the socket sometimes and thus we are vulnerable to
being killed by the signal if the server happens to go away unexpectedly.
Noticed while trying (futilely) to reproduce bug #3902.

This bug has been there all along, but since the situation is usually
only of interest to developers, I chose not to back-patch the changes.

in particular correct the obsolete claim that it can't be changed once
any plans have been cached.

whether to execute an immediate interrupt, rather than testing whether
LockWaitCancel() cancelled a lock wait.  The old way misclassified the case
where we were blocked in ProcWaitForSignal(), and arguably would misclassify
any other future additions of new ImmediateInterruptOK states too.  This
allows reverting the old kluge that gave LockWaitCancel() a return value,
since no callers care anymore.  Improve comments in the various
implementations of PGSemaphoreLock() to explain that on some platforms, the
assumption that semop() exits after a signal is wrong, and so we must ensure
that the signal handler itself throws elog if we want cancel or die interrupts
to be effective.  Per testing related to bug #3883, though this patch doesn't
solve those problems fully.

Perhaps this change should be back-patched, but since pre-8.3 branches aren't
really relying on autovacuum to respond to SIGINT, it doesn't seem critical
for them.

a double-pfree crash and another that effectively disabled size-based rotation
for CSV logs.  Also suppress a memory leak and make some trivial cosmetic
improvements.  Per bug #3901 from Chris Hoover and additional code-reading.

of escaping bytea return value. Both cases did not handle backslash values properly.

ri_FetchConstraintInfo, to avoid a query-duration memory leak when that
routine is called by RI_FKey_keyequal_upd_fk (which isn't executed in a
short-lived context).  This problem was latent when the routine was added
in February, but it didn't become serious until the varvarlena patch made
it quite likely that the fields being examined would be "toasted" (ie, have
short headers).  Per report from Stephen Denne.

TimestampTzPlusMilliseconds.  An integer argument of more than INT_MAX/1000
milliseconds (ie, about 35 minutes) would provoke a wrong result, resulting
in incorrect enforcement of statement_timestamp values larger than that.
Bug was introduced in my rewrite of 2006-06-20, which fixed some other
overflow risks, but missed this one :-(  Per report from Elein.

Per discussion of bug #3877.  Simon Riggs, some fixes by moi.

zero with a CASE expression.  Per gripe from Russell Smith.

no-longer-maintained PgAccess.  Per Erik Rijkers.

 * The temporary enabling of the caller opcode here is to work around a
 * bug in perl 5.10, which unkindly changed the way its Safe.pm works, without
 * notice. It is quite safe, as caller is informational only, and in any case
 * we only enable it while we load the 'strict' module.

wrong because of mismatched byte ordering.

regis.  Correct the latter's oversight that a bracket-expression needs to be
terminated.  Reduce the ereports to elogs, since they are now not expected to
ever be hit (thus addressing Alvaro's original complaint).
In passing, const-ify the string argument to RS_compile.

to format properly for the actually needed column width, instead of having
a hard-wired assumption about the longest command name length.  Also make it
respond to the current screen width.  In passing, const-ify the constant
table.

On other platforms it's better to let the Makefile handle it, but we want
the regression tests to be invokable without make on Windows.  A batch
file would be a better solution, but no time for that before 8.3.
Per my discovery that this breaks testing under SELinux, and subsequent
discussion.

must commit after autoconf ... and yes, I used the right autoconf

main code path for enlarging libpq's input buffer in one swoop when needing to
read a long data message.  Without this, the code will double the buffer size,
read more data, notice it still hasn't got the whole message, and repeat till
it finally has a large enough buffer.  Which wastes a lot of data-moving
effort and also memory (since malloc probably can't do anything very useful
with the freed-up smaller buffers).  Not sure why this wasn't there already;
certainly the COPY data path is a place where we're quite likely to see long
data messages.  I'm not backpatching though, since this is just a marginal
performance issue rather than a real bug.