Minor code review for json.c.

Improve commenting, conform to project style for use of ++ etc.
No functional changes.
Improve documentation of postgres -C option

Clarify help (s/return/print/), and explain that this option is for
use by other programs, not for user-facing use (it does not print
units).
In pg_upgrade, verify that the install user has the same oid on both
clusters, and make sure the new cluster has no additional users.

Backpatch to 9.1.
Support Linux's oom_score_adj API as well as the older oom_adj API.

The simplest way to handle this is just to copy-and-paste the relevant
code block in fork_process.c, so that's what I did. (It's possible that
something more complicated would be useful to packagers who want to work
with either the old or the new API; but at this point the number of such
people is rapidly approaching zero, so let's just get the minimal thing
done.)  Update relevant documentation as well.
Deprecate use of GLOBAL and LOCAL in temp table creation.

Aside from adjusting the documentation to say that these are deprecated,
we now report a warning (not an error) for use of GLOBAL, since it seems
fairly likely that we might change that to request SQL-spec-compliant temp
table behavior in the foreseeable future.  Although our handling of LOCAL
is equally nonstandard, there is no evident interest in ever implementing
SQL modules, and furthermore some other products interpret LOCAL as
behaving the same way we do.  So no expectation of change and no warning
for LOCAL; but it still seems a good idea to deprecate writing it.

Noah Misch
Fix description of SQL-standard meaning of CREATE LOCAL TEMP TABLE.

I had this slightly wrong, as noted by Noah Misch.
Revert "Reduce checkpoints and WAL traffic on low activity database server"

This reverts commit 18fb9d8d21a28caddb72c7ffbdd7b96d52ff9724.  Per
discussion, it does not seem like a good idea to allow committed changes to
go un-checkpointed indefinitely, as could happen in a low-traffic server;
that makes us entirely reliant on the WAL stream with no redundancy that
might aid data recovery in case of disk failure.

This re-introduces the original problem of hot-standby setups generating a
small continuing stream of WAL traffic even when idle, but there are other
ways to address that without compromising crash recovery, so we'll revisit
that issue in a future release cycle.
Remove release note entry for reverted patch.
Revisit error message details for JSON input parsing.

Instead of identifying error locations only by line number (which could
be entirely unhelpful with long input lines), provide a fragment of the
input text too, placing this info in a new CONTEXT entry.  Make the
error detail messages conform more closely to style guidelines, fix
failure to expose some of them for translation, ensure compiler can
check formats against supplied parameters.
Stamp HEAD as 9.3devel.

Let the hacking begin ...
Stamp library minor versions for 9.3.

This includes fixing the MSVC copy of ecpg/preproc's version info, which
seems to have been overlooked repeatedly.  Can't we fix that so there are
not two copies??
Flesh out RELEASE_CHANGES instructions for branching in git.

We have this info in the wiki, but it should be here too.
Add 9.2 branch to git_changelog's list.
Make \conninfo print SSL information.

Alastair Turner, per suggestion from Bruce Momjian.
Remove RELKIND_UNCATALOGED.

This may have been important at some point in the past, but it no
longer does anything useful.

Review by Tom Lane.
Remove misplaced sanity check from heap_create().

Even when allow_system_table_mods is not set, we allow creation of any
type of SQL object in pg_catalog, except for relations.  And you can
get relations into pg_catalog, too, by initially creating them in some
other schema and then moving them with ALTER .. SET SCHEMA.  So this
restriction, which prevents relations (only) from being created in
pg_catalog directly, is fairly pointless.  If we need a safety mechanism
for this, it should be placed further upstream, so that it affects all
SQL objects uniformly, and picks up both CREATE and SET SCHEMA.

For now, just rip it out, per discussion with Tom Lane.
Add new function log_newpage_buffer.

When I implemented the ginbuildempty() function as part of
implementing unlogged tables, I falsified the note in the header
comment for log_newpage.  Although we could fix that up by changing
the comment, it seems cleaner to add a new function which is
specifically intended to handle this case.  So do that.
During transaction cleanup, release locks before deleting files.

There's no need to hold onto the locks until the files are needed,
and by doing it this way, we reduce the impact on other backends who
may be awaiting locks we hold.

Noah Misch
New SQL functons pg_backup_in_progress() and pg_backup_start_time()

Darold Gilles, reviewed by Gabriele Bartolini and others, rebased by
Marco Nenciarini.  Stylistic cleanup and OID fixes by me.
Doc corrections for pg_is_in_backup patch.

Fujii Masao