For code-reuse in upcoming functionality in pg_basebackup.

Zoltan Boszormenyi

The PL/Python build on OS X was previously hardcoded to use the system
installation of Python, ignoring whatever was specified to configure.
Except that it would use the header files from configure, which could
lead to mismatches.  It was not possible to build against a custom
Python installation.

Now, we check in configure how the specified Python installation was
built and use that, supporting framework and non-framework builds.

This reverts commit be0dfbad.

The previous information that Py_RETURN_TRUE and Py_RETURN_FALSE are
supported in Python 2.3 is wrong.  They require Python 2.4.  Update the
comment about that.

Parameter defaults are actually in the SQL standard, while it was
previously claimed they were not.

SPI_execute() and related functions create a CachedPlan, execute it once,
and immediately discard it, so that the functionality offered by
plancache.c is of no value in this code path.  And performance measurements
show that the extra data copying and invalidation checking done by
plancache.c slows down simple queries by 10% or more compared to 9.1.
However, enough of the SPI code is shared with functions that do need plan
caching that it seems impractical to bypass plancache.c altogether.
Instead, let's invent a variant version of cached plans that preserves
99% of the API but doesn't offer any of the actual functionality, nor the
overhead.  This puts SPI_execute() performance back on par, or maybe even
slightly better, than it was before.  This change should resolve recent
complaints of performance degradation from Dong Ye, Pavel Stehule, and
others.

By avoiding data copying, this change also reduces the amount of memory
needed to execute many-statement SPI_execute() strings, as for instance in
a recent complaint from Tomas Vondra.

An additional benefit of this change is that multi-statement SPI_execute()
query strings are now processed fully serially, that is we complete
execution of earlier statements before running parse analysis and planning
on following ones.  This eliminates a long-standing POLA violation, in that
DDL that affects the behavior of a later statement will now behave as
expected.

Back-patch to 9.2, since this was a performance regression compared to 9.1.
(In 9.2, place the added struct fields so as to avoid changing the offsets
of existing fields.)

Heikki Linnakangas and Tom Lane

On non-Windows machines, we use the Unix socket for connections to test
postmasters, so there is no need to create a TCP socket.  Furthermore,
doing so causes failures due to port conflicts if two builds are carried
out concurrently on one machine.  (If the builds are done in different
chroots, which is standard practice at least in Red Hat distros, there
is no risk of conflict on the Unix socket.)  Suppressing the TCP socket
by setting listen_addresses to empty has long been standard practice
for pg_regress, and pg_upgrade knows about this too ... but pg_upgrade's
test.sh didn't get the memo.

Back-patch to 9.2, and also sync the 9.2 version of the script with HEAD
as much as practical.

If you take a base backup from a standby server with "pg_basebackup -X
fetch", and the timeline switches while the backup is being taken, the
backup used to fail with an error "requested WAL segment %s has already
been removed". This is because the server-side code that sends over the
required WAL files would not construct the WAL filename with the correct
timeline after a switch.

Fix that by using readdir() to scan pg_xlog for all the WAL segments in the
range, regardless of timeline.

Also, include all timeline history files in the backup, if taken with
"-X fetch". That fixes another related bug: If a timeline switch happened
just before the backup was initiated in a standby, the WAL segment
containing the initial checkpoint record contains WAL from the older
timeline too. Recovery will not accept that without a timeline history file
that lists the older timeline.

Backpatch to 9.2. Versions prior to that were not affected as you could not
take a base backup from a standby before 9.2.

Streaming replication can fetch any missing timeline history files from the
master, but recovery would read the timeline history file for the target
timeline before reading the checkpoint record, and before walreceiver has
had a chance to fetch it from the master. Delay reading it, and the sanity
checks involving timeline history, until after reading the checkpoint
record.

There is at least one scenario where this makes a difference: if you take
a base backup from a standby server right after a timeline switch, the
WAL segment containing the initial checkpoint record will begin with an
older timeline ID. Without the timeline history file, recovering that file
will fail as the older timeline ID is not recognized to be an ancestor of
the target timeline. If you try to recover from such a backup, using only
streaming replication to fetch the WAL, this patch is required for that to
work.

Adjust pg_upgrade page conversion functions (which are not used) to
return void so transfer_all_new_dbs can return void.

... not on auxiliary processes.  I managed to overlook the fact that I
had disabled assertions on my HEAD checkout long ago.

Hopefully this will turn the buildfarm green again, and put an end to
today's silliness.

This makes it possible to include them only where they are used, so
we can avoid the conflict of the uid_t and gid_t datatypes that happened
in plperl (since plperl doesn't need the tar functions)

Auxiliary and bootstrap processes weren't getting it, causing initdb to
fail completely.

Commit da07a1e8 was broken for EXEC_BACKEND because I failed to realize
that the MaxBackends recomputation needed to be duplicated by
subprocesses in SubPostmasterMain.  However, instead of having the value
be recomputed at all, it's better to assign the correct value at
postmaster initialization time, and have it be propagated to exec'ed
backends via BackendParameters.

MaxBackends stays as zero until after modules in
shared_preload_libraries have had a chance to register bgworkers, since
the value is going to be untrustworthy till that's finished.

Heikki Linnakangas and Álvaro Herrera

After receiving some WAL over streaming replication, try to open the file
from the timeline we're currently recieving, not recoveryTargetTLI. They
are usually the same, which is why wasn't noticed before, but you'd get
an error if there have been more than one timeline switch between the
current point in WAL and the recovery target.

Fully update git head, and update back branches in ./COPYRIGHT and
legal.sgml files.

Move some of the tar functionality that existed mostly duplicated
in both pg_dump and the walsender basebackup functionality into
port/tar.c instead, so it can be used from both. It will also be
used by pg_basebackup in the future, which would've caused a third
copy of it around.

Zoltan Boszormenyi and Magnus Hagander

Plus some other minor clarifications to Windows build instructions.

Craig Ringer, with minor editorialization by me.

This was changed in commit 038f3a05, including
the description in the docs, but the reference was missed.

Fujii Masao

In commit 11e13185, we improved the
rule/view dumping code so that it would produce valid query representations
even if some of the tables involved in a query had been renamed since the
query was parsed.  This patch extends that idea to fix problems that occur
when individual columns are renamed, or added or dropped.  As before, the
core of the fix is to assign unique new aliases when a name conflict has
been created.  This is complicated by the JOIN USING feature, which
requires the same column alias to be used in both input relations, but we
can handle that with a sufficiently complex approach to assigning aliases.

A fortiori, this patch takes care of situations where the query didn't have
unique column names to begin with, such as in a recent complaint from Bryan
Nuse.  (Because of expansion of "SELECT *", re-parsing a dumped query can
require column name uniqueness even though the original text did not.)

The ldapurl option doesn't actually support specifying a user name and
password.

Albe Laurenz

The cascading standby patch in 9.2 changed the way WAL files are treated
when restored from the archive. Before, they were restored under a temporary
filename, and not kept in pg_xlog, but after the patch, they were copied
under pg_xlog. This is necessary for a cascading standby to find them, but
it also means that if the archive goes offline and a standby is restarted,
it can recover back to where it was using the files in pg_xlog. It also
means that if you take an offline backup from a standby server, it includes
all the required WAL files in pg_xlog.

However, the same change was not made to timeline history files, so if the
WAL segment containing the checkpoint record contains a timeline switch, you
will still get an error if you try to restart recovery without the archive,
or recover from an offline backup taken from the standby.

With this patch, timeline history files restored from archive are copied
into pg_xlog like WAL files are, so that pg_xlog contains all the files
required to recover. This is a corner-case pre-existing issue in 9.2, but
even more important in master where it's possible for a standby to follow a
timeline switch through streaming replication. To make that possible, the
timeline history files must be present in pg_xlog.

Parts of the description had claimed incorrect pg_hba.conf option names
for LDAP authentication.

Albe Laurenz

This is again intended to support extensions to the event trigger
functionality.  This may go a bit further than we need for that
purpose, but there's some value in being consistent, and the OID
may be useful for other purposes also.

Dimitri Fontaine

This gets rid of XLByteLT, XLByteLE, XLByteEQ and XLByteAdvance.
These were useful for brevity when XLogRecPtrs were split in
xlogid/xrecoff; but now that they are simple uint64's, they are just
clutter.  The only downside to making this change would be ease of
backporting patches, but that has been negated by other substantive
changes to the involved code anyway.  The clarity of simpler expressions
makes the change worthwhile.

Most of the changes are mechanical, but in a couple of places, the patch
author chose to invert the operator sense, making the code flow more
logical (and more in line with preceding comments).

Author: Andres Freund
Eyeballed by Dimitri Fontaine and Alvaro Herrera

For consistency.

Author: Andres Freund

Commit 061e7efb did away with its last caller, but neglected to remove
the actual definition.

Author: Andres Freund

Add pg_upgrade --jobs, which allows parallel dump/restore of databases,
which improves performance.

Code review for commit 2f582f76: don't use
a static variable for what ought to be a deparse_context field, fix
non-multibyte-safe test for spaces, avoid useless and potentially O(N^2)
(though admittedly with a very small constant) calculations of wrap
positions when we aren't going to wrap.

Ensure comments accurately reflect state of code
given new understanding, and recent changes.
Include example code from Noah Misch to
illustrate how rd_newRelfilenodeSubid can be
reset deterministically. No code changes.

Teach RelationCacheInvalidate() to keep rd_newRelfilenodeSubid across rel cache
message overflows, so that behaviour is now fully deterministic.

Noah Misch

by unmatched function prototypes.

Andres Freund

Extracted from a larger patch by Dimitri Fontaine.  It is hoped that
this will provide infrastructure for enriching the new event trigger
functionality, but it seems possibly useful for other purposes as
well.

transformExpr() is required to cope with already-transformed expression
trees, for various ugly-but-not-quite-worth-cleaning-up reasons.  However,
some of its newer subroutines hadn't gotten the memo.  This accounts for
bug #7763 from Norbert Buchmuller: transformRowExpr() was overwriting the
previously determined type of a RowExpr during CREATE TABLE LIKE INCLUDING
INDEXES.  Additional investigation showed that transformXmlExpr had the
same kind of problem, but all the other cases seem to be safe.

Andres Freund and Tom Lane