Previously, 'yesterday 04:00:00'::timestamp didn't do the same thing as
'04:00:00 yesterday'::timestamp, and the return value from the latter
was midnight rather than the specified time.

Dean Rasheed, with some stylistic changes

Some of the ASCII art expected 8-space tab stops, and some of it
expected 4-space tab stops.

Per report from YAMAMOTO Takashi.

Per bug #6181 from Itagaki Takahiro.  Also do some marginal code cleanup
and improve error handling.

Per my testing, this works just as well with gcc as it does with HP's
compiler; and there is no reason to think that the effect doesn't occur
with icc, either.

Also, rewrite the header comment about enforcing sequencing around spinlock
operations, per Robert's gripe that it was misleading.

At least on this architecture, it's very important to spin on a
non-atomic instruction and only retry the atomic once it appears
that it will succeed.  To fix this, split TAS() into two macros:
TAS(), for trying to grab the lock the first time, and TAS_SPIN(),
for spinning until we get it.  TAS_SPIN() defaults to same as TAS(),
but we can override it when we know there's a better way.

It's likely that some of the other cases in s_lock.h require
similar treatment, but this is the only one we've got conclusive
evidence for at present.

On closer inspection, whining in restore_toc_entries_parallel is really
much too late for any user-facing error case.  The right place to do it
is at the start of RestoreArchive(), before we've done anything interesting
(suh as trying to DROP all the targets ...)

Back-patch to 8.4, where parallel restore was introduced.

If we are unable to do a parallel restore because the input file is stdin
or is otherwise unseekable, we should complain and fail immediately, not
after having done some of the restore.  Complaining once per thread isn't
so cool either, and the messages should be worded to make it clear this is
an unsupported case not some weird race-condition bug.  Per complaint from
Lonni Friedman.

Back-patch to 8.4, where parallel restore was introduced.

Without this, it's not very easy to tell which compiler version a buildfarm
animal is actually using at the moment.

their own.

Avoid compile problems with defines being redefined after the removal of
the #if blocks.

Change script to use shell functions for simplicity.

These days, such a response is far more likely to signify a server-side
problem, such as fork failure.  Reporting "server does not support SSL"
(in sslmode=require) could be quite misleading.  But the results could
be even worse in sslmode=prefer: if the problem was transient and the
next connection attempt succeeds, we'll have silently fallen back to
protocol version 2.0, possibly disabling features the user needs.

Hence, it seems best to just eliminate the assumption that backing off
to non-SSL/2.0 protocol is the way to recover from an "E" response, and
instead treat the server error the same as we would in non-SSL cases.

I tested this change against a pre-7.0 server, and found that there
was a second logic bug in the "prefer" path: the test to decide whether
to make a fallback connection attempt assumed that we must have opened
conn->ssl, which in fact does not happen given an "E" response.  After
fixing that, the code does indeed connect successfully to pre-7.0,
as long as you didn't set sslmode=require.  (If you did, you get
"Unsupported frontend protocol", which isn't completely off base
given the server certainly doesn't support SSL.)

Since there seems no reason to believe that pre-7.0 servers exist anymore
in the wild, back-patch to all supported branches.

There are assorted situations wherein PQconnectPoll() will abandon a
connection attempt and try again with different parameters (eg, SSL versus
not SSL).  However, the code forgot to discard any pending data in libpq's
I/O buffers when doing this.  In at least one case (server returns E
message during SSL negotiation), there is unread input data which bollixes
the next connection attempt.  I have not checked to see whether this is
possible in the other cases where we close the socket and retry, but it
seems like a matter of good defensive programming to add explicit
buffer-flushing code to all of them.

This is one of several issues exposed by Daniel Farina's report of
misbehavior after a server-side fork failure.

This has been wrong since forever, so back-patch to all supported branches.

include dependencies.

Modify pgcompinclude to skip a common fcinfo error.

In PostgreSQL, this is included in the SELECT privilege, so show YES
or NO depending on whether SELECT is granted.

remove from local *.h files.

Per suggestion from Alvaro.

.h include files before .c files.

Mark some includes as needed to be ignored by pgrminclude.

tsvector_concat() allocated its result workspace using the "conservative"
estimate of the sum of the two input tsvectors' sizes.  Unfortunately that
wasn't so conservative as all that, because it supposed that the number of
pad bytes required could not grow.  Which it can, as per test case from
Jesper Krogh, if there's a mix of lexemes with positions and lexemes
without them in the input data.  The fix is to assume that we might add
a not-previously-present pad byte for each and every lexeme in the two
inputs; which really is conservative, but it doesn't seem worthwhile to
try to be more precise.

This is an aboriginal bug in tsvector_concat, so back-patch to all
versions containing it.

These changes allow backtick command evaluation and psql variable
interpolation to happen on substrings of a single meta-command argument.
Formerly, no such evaluations happened at all if the backtick or colon
wasn't the first character of the argument, and we considered an argument
completed as soon as we'd processed one backtick, variable reference, or
quoted substring.  A string like 'FOO'BAR was thus taken as two arguments
not one, not exactly what one would expect.  In the new coding, an argument
is considered terminated only by unquoted whitespace or backslash.

Also, clean up a bunch of omissions, infelicities and outright errors in
the psql documentation of variables and metacommand argument syntax.

As in the backend, the implementation actually accepts any non-ASCII
character, but we only document that you can use letters.

flex puts lex.backup in the current working directory regardless
of where the input and output are.

#if/#ifdefs.

introduced recently when trying to filter out temp tables.

Backpatch to 9.0 and 9.1.

This was deemed unnecessary initially but in later discussion it was
agreed otherwise.

Original file from Kevin Grittner, allegedly from Dan Ports.
I had to clean up whitespace a bit per changes from Heikki.

Per discussion, we should enforce the policy of "no backtracking" in these
performance-sensitive scanners.