In commit 6545a901, I removed the mini SQL
lexer that was in pg_backup_db.c, thinking that it had no real purpose
beyond separating COPY data from SQL commands, which purpose had been
obsoleted by long-ago fixes in pg_dump's archive file format.
Unfortunately this was in error: that code was also used to identify
command boundaries in INSERT-style table data, which is run together as a
single string in the archive file for better compressibility.  As a result,
direct-to-database restores from archive files made with --inserts or
--column-inserts fail in our latest releases, as reported by Dick Visser.

To fix, restore the mini SQL lexer, but simplify it by adjusting the
calling logic so that it's only required to cope with INSERT-style table
data, not arbitrary SQL commands.  This allows us to not have to deal with
SQL comments, E'' strings, or dollar-quoted strings, none of which have
ever been emitted by dumpTableData_insert.

Also, fix the lexer to cope with standard-conforming strings, which was the
actual bug that the previous patch was meant to solve.

Back-patch to all supported branches.  The previous patch went back to 8.2,
which unfortunately means that the EOL release of 8.2 contains this bug,
but I don't think we're doing another 8.2 release just because of that.

As noted by Heikki Linnakangas, the previous coding confused the "flags"
variable with the "mask" variable.  The affect of this appears to be that
unlogged buffers would get written out at every checkpoint rather than
only at shutdown time.  Although that's arguably an acceptable failure
mode, I'm back-patching this change, since it seems like a poor idea to
rely on this happening to work.

Apparently the perl garbage collector was a bit too eager, so here
we control when the new SV is garbage collected.

Dump them using line breaks and indentation instead of everything on
one line.

pg_dump sorts operators by name, but operators with the same name come
out in random order.  Now operators with the same name are dumped in
the order prefix, postfix, infix.  (This is consistent with functions,
which are dumped in increasing number of argument order.)

ALTER DOMAIN / DROP CONSTRAINT on a nonexistent constraint name did
not report any error.  Now it reports an error.  The IF EXISTS option
was added to get the usual behavior of ignoring nonexistent objects to
drop.

Certain things like typeglobs or readonly things like $^V cause
perl's SvPVutf8() to die nastily and crash the backend. To avoid
that bug we make a copy of the object, which will subsequently be
garbage collected.

Back patched to 9.1 where we first started using SvPVutf8().

Per -hackers discussion. Original problem reported by David Wheeler.

This list is now freed when the last connection has been closed.

Closes: #6366

As previously coded, the QueryDesc's dest pointer was left dangling
(pointing at an already-freed receiver object) after ExecutorEnd.  It's a
bit astonishing that it took us this long to notice, and I'm not sure that
the known problem case with SQL functions is the only one.  Fix it by
saving and restoring the original receiver pointer, which seems the most
bulletproof way of ensuring any related bugs are also covered.

Per bug #6379 from Paul Ramsey.  Back-patch to 8.4 where the current
handling of SELECT INTO was introduced.

Further testing convinces me that this is helpful at sufficiently high
contention levels, though it's still worrisome that it loses slightly
at lower contention levels.

Per Manabu Ori.

Brar Piening, reviewed by Craig Ringer.

atexit() hook

Because coerce_type recurses into the argument of a CollateExpr,
coerce_to_target_type's longstanding code for detecting whether coerce_type
had actually done anything (to wit, returned a different node than it
passed in) was broken in 9.1.  This resulted in unexpected failures in
hide_coercion_node; which was not the latter's fault, since it's critical
that we never call it on anything that wasn't inserted by coerce_type.
(Else we might decide to "hide" a user-written function call.)

Fix by removing and replacing the CollateExpr in coerce_to_target_type
itself.  This is all pretty ugly but I don't immediately see a way to make
it nicer.

Per report from Jean-Yves F. Barbier.

This is allegedly a win, at least on some PPC implementations, according
to the PPC ISA documents.  However, as with LWARX hints, some PPC
platforms give an illegal-instruction failure.  Use the same trick as
before of assuming that PPC64 platforms will accept it; we might need to
refine that based on experience, but there are other projects doing
likewise according to google.

I did not add an assembler compatibility test because LWSYNC has been
around much longer than hint bits, and it seems unlikely that any
toolchains currently in use don't recognize it.

Previously we defined slock_t as 8 bytes on PPC64, but the TAS assembly
code uses word-wide operations regardless, so that the second word was
just wasted space.  There doesn't appear to be any performance benefit
in adding the second word, so get rid of it to simplify the code.

The hint bit makes for a small but measurable performance improvement
in access to contended spinlocks.

On the other hand, some PPC chips give an illegal-instruction failure.
There doesn't seem to be a completely bulletproof way to tell whether the
hint bit will cause an illegal-instruction failure other than by trying
it; but most if not all 64-bit PPC machines should accept it, so follow
the Linux kernel's lead and assume it's okay to use it in 64-bit builds.
Of course we must also check whether the assembler accepts the command,
since even with a recent CPU the toolchain could be old.

Patch by Manabu Ori, significantly modified by me.

directories.  Per suggestion from Andrew Dunstan.

those files corrupts the index.

Allows streaming replication users to calculate transfer latency
and apply delay via internal functions. No external functions yet.

This reverts commit ff68b256.
The recent change to use -fexcess-precision=standard should make those
Asserts safe, and does fix a test case that formerly crashed for me,
so I think there's no need to have a cross-version difference in the
code here.

to 'make' rather than 'gmake' for the binary name.

The original test cases gave varying results depending on whether the
locale sorts digits before or after letters.  Since that's not really
what we wish to test here, adjust the test data to not contain any strings
beginning with digits.  Per report from Pavel Stehule.

For easier source reading

This is to get a deterministic dump order independent of the order in
which the user mappings were created.

Always compare the return value to 0, don't use cute tricks like
if (!strcmp(...)).

All supported platforms support the C89 standard function atexit()
(SunOS 4 probably being the last one not to), and supporting both
makes the code clumsy.

This is the standard behavior but was forgotten in some places.

That way, the result of a msgmerge is more deterministic and not
dependent on the order in which the files are found.

That way, the created .pot file is more deterministic and not
dependent on the order in which the files are found.