These variables no longer have any useful purpose, since there's no reason
to special-case brute force timezones now that we have a valid
session_timezone setting for them.  Remove the variables, and remove the
SET/SHOW TIME ZONE code that deals with them.

The user-visible impact of this is that SHOW TIME ZONE will now show a
POSIX-style zone specification, in the form "<+-offset>-+offset", rather
than an interval value when a brute-force zone has been set.  While perhaps
less intuitive, this is a better definition than before because it's
actually possible to give that string back to SET TIME ZONE and get the
same behavior, unlike what used to happen.

We did not previously mention the angle-bracket syntax when describing
POSIX timezone specifications; add some documentation so that people
can figure out what these strings do.  (There's still quite a lot of
undocumented functionality there, but anybody who really cares can
go read the POSIX spec to find out about it.  In practice most people
seem to prefer Olsen-style city names anyway.)

The only remaining places where we actually look at CTimeZone/HasCTZSet
are abstime2tm() and timestamp2tm().  Now that session_timezone is always
valid, we can remove these special cases.  The caller-visible impact of
this is that these functions now always return a valid zone abbreviation
if requested, whereas before they'd return a NULL pointer if a brute-force
timezone was in use.  In the existing code, the only place I can find that
changes behavior is to_char(), whose TZ format code will now print
something useful rather than nothing for such zones.  (In the places where
the returned zone abbreviation is passed to EncodeDateTime, the lack of
visible change is because we've chosen the abbreviation used for these
zones to match what EncodeTimezone would have printed.)

It's likely that there is now a fair amount of removable dead code around
the call sites, namely anything that's meant to cope with getting a NULL
timezone abbreviation, but I've not made an effort to root that out.

This could be back-patched if we decide we'd like to fix to_char()'s
behavior in the back branches, but there doesn't seem to be much
enthusiasm for that at present.

Formerly, when using a SQL-spec timezone setting with a fixed GMT offset
(called a "brute force" timezone in the code), the session_timezone
variable was not updated to match the nominal timezone; rather, all code
was expected to ignore session_timezone if HasCTZSet was true.  This is
of course obviously fragile, though a search of the code finds only
timeofday() failing to honor the rule.  A bigger problem was that
DetermineTimeZoneOffset() supposed that if its pg_tz parameter was
pointer-equal to session_timezone, then HasCTZSet should override the
parameter.  This would cause datetime input containing an explicit zone
name to be treated as referencing the brute-force zone instead, if the
zone name happened to match the session timezone that had prevailed
before installing the brute-force zone setting (as reported in bug #8572).
The same malady could affect AT TIME ZONE operators.

To fix, set up session_timezone so that it matches the brute-force zone
specification, which we can do using the POSIX timezone definition syntax
"<abbrev>offset", and get rid of the bogus lookaside check in
DetermineTimeZoneOffset().  Aside from fixing the erroneous behavior in
datetime parsing and AT TIME ZONE, this will cause the timeofday() function
to print its result in the user-requested time zone rather than some
previously-set zone.  It might also affect results in third-party
extensions, if there are any that make use of session_timezone without
considering HasCTZSet, but in all cases the new behavior should be saner
than before.

Back-patch to all supported branches.

This shaves a few cycles, and generally seems like good programming
practice.

David Rowley

Apparently, shifts greater than or equal to the width of the type
are undefined, and can surprisingly produce a non-zero value.

Amit Kapila, with a comment by me.

NFAs have children, but their individual states don't.

The C and POSIX standards state that strncpy's behavior is undefined when
source and destination areas overlap.  While it remains dubious whether any
implementations really misbehave when the pointers are exactly equal, some
platforms are now starting to force the issue by complaining when an
undefined call occurs.  (In particular OS X 10.9 has been seen to dump core
here, though the exact set of circumstances needed to trigger that remain
elusive.  Similar behavior can be expected to be optional on Linux and
other platforms in the near future.)  So tweak the code to explicitly do
nothing when nothing need be done.

Back-patch to all active branches.  In HEAD, this also lets us get rid of
an exception in valgrind.supp.

Per discussion of a report from Matthias Schmitt.

This is more consistent with what we do elsewhere.

The NetBSD shell apparently returns non-zero from an unset command if
the variable is already unset. This matters when, as in pg_upgrade's
test.sh, we are working under 'set -e'. To protect against this, we
first set the PG variables to an empty string before unsetting them
completely.

Error found on buildfarm member coypu, solution from Rémi Zara.

SGML documentation, as well as code comments, failed to note that an FDW's
validator will be applied to foreign-table options for foreign tables using
the FDW.

Etsuro Fujita

We don't need two index entries for lo_create pointing at the same section.
It's a bit pedantic for the toolchain to warn about this, but warn it does.

With these, one need no longer manipulate large object descriptors and
extract numeric constants from header files in order to read and write
large object contents from SQL.

Pavel Stehule, reviewed by Rushabh Lathia.

The rules regression test prints all known views and rules, which is a set
that changes regularly.  Previously, a change in one rule would frequently
lead to whitespace changes across the entire output of this query, which is
painful to verify and causes undesirable conflicts between unrelated patch
sets.  Use \a mode to improve matters.  Also use \t mode to suppress the
total-rows count, which was also a source of unnecessary patch conflicts.

Likewise modify the output mode for the list of indexed tables generated
in sanity_check.sql.  There might be other places where we should use this
idea, but these are the ones that have caused the most problems.

Andres Freund

When using a C99-compliant vsnprintf, we can use its report of the required
buffer size to avoid making multiple loops through the formatting logic.
This is similar to the changes recently made in stringinfo.c, but we can't
use psprintf.c here because in libpq we don't want to exit() on error.
(The behavior pqexpbuffer.c has historically used is to mark the
PQExpBuffer as "broken", ie empty, if it runs into any fatal problem.)

To avoid duplicating code more than necessary, I refactored
printfPQExpBuffer and appendPQExpBuffer to share a subroutine that's
very similar to psprintf.c's pvsnprintf in spirit.

It's not entirely clear why some PPC machines are generating -0 here, since
the underlying computation should be exactly 0 - 0.  Perhaps there's some
wider-than-nominal-precision calculations happening?  Anyway, the best way
to avoid platform-dependent results seems to be to explicitly reset -0 to
regular zero.

This reverts commit a0a546f0.
It seems better to tweak the code to suppress -0 results during
line_construct_pts(), which I'll do in the next commit.

This prevents the recently-added probe for shm_open() from crashing
on platforms that are impolite enough to deliver a signal rather than
returning ENOSYS for an unimplemented kernel call.  At least on the
one known example (HPUX 10.20), ignoring SIGSYS does result in the
desired behavior of getting an ENOSYS error return instead.

Per discussion, we might later wish to do this in the backend as well,
but for now it seems sufficient to do it in initdb.

When we are using a C99-compliant vsnprintf implementation (which should be
most places, these days) it is worth the trouble to make use of its report
of how large the buffer needs to be to succeed.  This patch adjusts
stringinfo.c and some miscellaneous usages in pg_dump to do that, relying
on the logic recently added in libpgcommon's psprintf.c.  Since these
places want to know the number of bytes written once we succeed, modify the
API of pvsnprintf() to report that.

There remains near-duplicate logic in pqexpbuffer.c, but since that code
is in libpq, psprintf.c's approach of exit()-on-error isn't appropriate
for use there.  Also note that I didn't bother touching the multitude
of places that call (v)snprintf without any attempt to provide a resizable
buffer.

Release-note-worthy incompatibility: the API of appendStringInfoVA()
changed.  If there's any third-party code that's calling that directly,
it will need tweaking along the same lines as in this patch.

David Rowley and Tom Lane

When a backend process is forked, we initialize the system's random number
generator with srandom(). The seed used is derived from the backend's pid
and the timestamp. However, we only used the microseconds part of the
timestamp, and it was XORed with the pid, so the total range of different
seed values chosen was 0-999999. That's quite limited.

Change the code to also use the seconds part of the timestamp in the seed,
and shift the microseconds so that all 32 bits of the seed are used.

Honza Horak

Move random() and setseed() to a separate table, to have them grouped
together. Also add a notice that random() is not cryptographically secure.

Original patch by Honza Horak, although I didn't use his version.

The absolute path to config file was not pfreed. There are probably more
small leaks here and there in the config file reload code and assign hooks,
and in practice no-one reloads the config files frequently enough for it to
be a problem, but this one is trivial enough that might as well fix it.

Backpatch to 9.3 where the leak was introduced.

Hari Babu

Since an increasing number of views and foreign tables are now able
to be updated, complete with any table, view, or foreign table in
the relevant contexts.  This avoids the need to use a complex
query that may be both confusing to end-users and nonperformant
to construct the list of possible completions.

Dean Rasheed, persuant to a complaint from Bernd Helme and a
suggestion from Peter Eisentraut

Use a critical section when setting the all-visible flag on an empty page,
and WAL-logging it. log_newpage_buffer() contains an assertion that it
must be called inside a critical section, and it's the right thing to do
when modifying a buffer anyway.

Also, the page should be marked dirty before calling log_newpage_buffer(),
per the comment in log_newpage_buffer() and src/backend/access/transam/README.

Patch by Andres Freund, in response to my report. Backpatch to 9.2, like
the patch that introduced these bugs (a6370fd9).

To wit,
bgworker.c: In function `RegisterDynamicBackgroundWorker':
bgworker.c:761: warning: `generation' might be used uninitialized in this function
dsm_impl.c: In function `dsm_impl_op':
dsm_impl.c:197: warning: control reaches end of non-void function

Neither of these represent actual bugs, but we may as well tweak the code
so that more compilers can tell that.  This won't change the generated code
on compilers that do recognize that the cases are unreachable.

This eliminates an awkward coding pattern that's also unnecessarily
inconsistent with backend coding.  psprintf() is now the thing to
use everywhere.

asprintf(), aside from not being particularly portable, has a fundamentally
badly-designed API; the psprintf() function that was added in passing in
the previous patch has a much better API choice.  Moreover, the NetBSD
implementation that was borrowed for the previous patch doesn't work with
non-C99-compliant vsnprintf, which is something we still have to cope with
on some platforms; and it depends on va_copy which isn't all that portable
either.  Get rid of that code in favor of an implementation similar to what
we've used for many years in stringinfo.c.  Also, move it into libpgcommon
since it's not really libpgport material.

I think this patch will be enough to turn the buildfarm green again, but
there's still cosmetic work left to do, namely get rid of pg_asprintf()
in favor of using psprintf().  That will come in a followon patch.

Previous commit modified the test case, but I didn't update cube.out
expected output file in previous commit because it was not needed by the
platforms I have easy access to. Buildfarm animal 'dugong', running
"Debian 4.0 icc 10.1.011 ia64", has now gone red because of that, so update
it now.

Also adjust cube_3.out. According to git history, it was added to support
64-bit MinGW. There is no such animal in the buildfarm, so I'm doing this
blindly, but it was added quite recently so maybe someone still cares.

Doesn't anybody here pay attention to compiler warnings?

If the lower left and upper right corners of a cube are the same, set a
flag in the cube header, and only store one copy of the coordinates. That
cuts the on-disk size into half for the common case that the cube datatype
is used to represent points rather than boxes.

The new format is backwards-compatible with the old one, so pg_upgrade
still works. However, to get the space savings, the data needs to be
rewritten. A simple VACUUM FULL or REINDEX is not enough, as the old
Datums will just be moved to the new heap/index as is. A pg_dump and
reload, or something similar like casting to text and back, will do the
trick.

This patch deliberately doesn't update all the alternative expected output
files, as I don't have access to machines that produce those outputs. I'm
not sure if they are still relevant, but if they are, the buildfarm will
tell us and produce the diff required to fix it. If none of the buildfarm
animals need them, they should be removed altogether.

Patch by Stas Kelvich.

Add a makefile rule for building PDFs with FOP.  Two new build targets
in doc/src/sgml are postgres-A4-fop.pdf and postgres-US-fop.pdf.

Run .fo output through xmllint for reformatting, so that errors are
easier to find.  (The default output has hardly any line breaks, so you
might be looking for an error in column 20000.)

Set some XSLT parameters to optimize for building with FOP.

Remove some redundant or somewhat useless chapterinfo/author
information, because it renders strangely with the FO stylesheet.
Reviewed-by: Álvaro Herrera <alvherre@2ndquadrant.com>

This avoids an assumption about the signed number representation.  It is
anticipated to have no functional changes on supported configurations;
many two's complement assumptions remain elsewhere.

Per a suggestion from Andres Freund.

This ought to have been done when libpgcommon was split off from
libpgport.

It requires pgfnames() from libpgcommon.

It requires pstrdup() from libpgcommon.

Previously, unless all columns were auto-updateable, we wouldn't
inserts, updates, or deletes, or at least not without a rule or trigger;
now, we'll allow inserts and updates that target only the auto-updateable
columns, and deletes even if there are no auto-updateable columns at
all provided the view definition is otherwise suitable.

Dean Rasheed, reviewed by Marko Tiikkaja