Multixact truncation is now handled differently, and this file hadn't
gotten the memo.

Per note from Amit Langote.  I didn't use his patch, though.

Also update the description of infomask bits, which weren't completely up
to date either.  This commit also propagates b01a4f68 back to 9.3 and
9.4, which apparently I failed to do back then.

Some of this is made possible by commit
9b74f32cdbff8b9be47fc69164eae552050509ff which lets pushJsonbValue
handle binary Jsonb values, meaning that clients no longer have to, and
some is just doing things in simpler and more straightforward ways.

Report by Michael Paquier

Must reset the "reached end" flag and reorder queue at rescan.

Per report from Regina Obe, bug #13349

This is because there are many __asm__ blocks there that pgindent messes
up.  Also configure pgindent to skip that directory in the future.

Fix some places where pgindent did silly stuff, often because project
style wasn't followed to begin with.  (I've not touched the atomics
headers, though.)

The name objectType is widely used as a field name, and it's pure luck that
this conflict has not caused pgindent to go crazy before.  It messed up
pg_audit.c pretty good though.  Since pg_shdepend.c doesn't export this
typedef and only uses it in three places, changing that seems saner than
changing the field usages.

Back-patch because we're contemplating using the union of all branch
typedefs for future pgindent runs, so this won't fix anything if it
stays the same in back branches.

Per an off-list question from Piotr Stefaniak.

Remove a bunch of "extern Datum foo(PG_FUNCTION_ARGS);" declarations that
are no longer needed now that PG_FUNCTION_INFO_V1(foo) provides that.

Some of these were evidently missed in commit e7128e8d, but others
were cargo-culted in in code added since then.  Possibly that can be blamed
in part on the fact that we'd not fixed relevant documentation examples,
which I've now done.

Maybe we should actually support this, but for the moment let's just
throw an error if the opclass tries it.

Typo in commit 7cbee7c0.  No practical effect since the buffer should
never actually be overrun, but various compilers and static analyzers will
whine about it.

Petr Jelinek

Fix confusion in documentation, substantial memory leakage if float8 or
float4 are pass-by-reference, and assorted comments that were obsoleted
by commit 98edd617.

Expand testing of rule deparsing a good bit, it's evidently needed.

Author: Peter Geoghegan, Andres Freund
Discussion: CAM3SWZQmXxZhQC32QVEOTYfNXJBJ_Q2SDENL7BV14Cq-zL0FLg@mail.gmail.com

Previously, INSERT with ON CONFLICT DO UPDATE specified used a new
command tag -- UPSERT.  It was introduced out of concern that INSERT as
a command tag would be a misrepresentation for ON CONFLICT DO UPDATE, as
some affected rows may actually have been updated.

Alvaro Herrera noticed that the implementation of that new command tag
was incomplete; in subsequent discussion we concluded that having it
doesn't provide benefits that are in line with the compatibility breaks
it requires.

Catversion bump due to the removal of PlannedStmt->isUpsert.

Author: Peter Geoghegan
Discussion: 20150520215816.GI5885@postgresql.org

Silly oversight in commit 1dc5ebc9:
when array2 is an expanded array, it might have array2->xpn.dnulls equal
to NULL, indicating the array is known null-free.  The code wasn't
expecting that, because it formerly always used deconstruct_array() which
always delivers a nulls array.

Per bug #13334 from Regina Obe.

pushJsonbValue was accepting jbvBinary objects passed as WJB_ELEM or
WJB_VALUE data. While this succeeded, when those objects were later
encountered in attempting to convert the result to Jsonb, errors
occurred. With this change we ghuarantee that a JSonbValue constructed
from calls to pushJsonbValue does not contain any jbvBinary objects.
This cures a problem observed with jsonb_delete.

This means callers of pushJsonbValue no longer need to perform this
unpacking themselves. A subsequent patch will perform some cleanup in
that area.

The error was not triggered by any 9.4 code, but this is a publicly
visible routine, and so the error could be exercised by third party
code, therefore backpatch to 9.4.

Bug report from Peter Geoghegan, fix by me.

Fabrízio Mello

With commit de768844, a copy of the partial segment was archived with the
.partial suffix, but the original file was still left in pg_xlog, so it
didn't actually solve the problems with archiving the partial segment that
it was supposed to solve. With this patch, the partial segment is renamed
rather than copied, so we only archive it with the .partial suffix.

Also be more robust in detecting if the last segment is already being
archived. Previously I used XLogArchiveIsBusy() for that, but that's not
quite right. With archive_mode='always', there might be a .ready file for
it, and we don't want to rename it to .partial in that case.

The old segment is needed until we're fully committed to the new timeline,
i.e. until we've written the end-of-recovery WAL record and updated the
min recovery point and timeline in the control file. So move the renaming
later in the startup sequence, after all that's been done.

Paul Ramsey reported that commit 35fcb1b3
induced a core dump on commuted ORDER BY expressions, because it was
assuming that the indexorderby expression could be found verbatim in the
relevant equivalence class, but it wasn't there.  We really don't need
anything that complicated anyway; for the data types likely to be used for
index ORDER BY operators in the foreseeable future, the exprType() of the
ORDER BY expression will serve fine.  (The case where we'd have to work
harder is where the ORDER BY expression's result is only binary-compatible
with the declared input type of the ordering operator; long before worrying
about that, one would need to get rid of GiST's hard-wired assumption that
said datatype is float8.)

Aside from fixing that crash and adding a regression test for the case,
I did some desultory code review:

nodeIndexscan.c was likewise overthinking how hard it ought to work to
identify the datatype of the ORDER BY expressions.

Add comments explaining how come nodeIndexscan.c can get away with
simplifying assumptions about NULLS LAST ordering and no backward scan.

Revert no-longer-needed changes of find_ec_member_for_tle(); while the
new definition was no worse than the old, it wasn't better either, and
it might cause back-patching pain.

Revert entirely bogus additions to genam.h.

We want this struct to be exactly a series of 3 int16 words, no more
and no less.  Historically, at least, some ARM compilers preferred to
pad it to 8 bytes unless coerced.  Our old way of doing that was just
to use __attribute__((packed)), but as pointed out by Piotr Stefaniak,
that does too much: it also licenses the compiler to give the struct
only byte-alignment.  We don't want that because it adds access overhead,
possibly quite significant overhead.  According to the GCC manual, what
we want requires also specifying __attribute__((align(2))).  It's not
entirely clear if all the relevant compilers accept this pragma as well,
but we can hope the buildfarm will tell us if not.  We can also add a
static assertion that should fire if the compiler padded the struct.

Since the combination of these pragmas should define exactly what we
want on any compiler that accepts them, let's try using them wherever
we think they exist, not only for __arm__.  (This is likely to expose
that the conditional definitions in c.h are inadequate, but finding
that out would be a good thing.)

The immediate motivation for this is that the current definition of
ExecRowMark allows its curCtid field to be misaligned.  It is not clear
whether there are any other uses of ItemPointerData with a similar hazard.
We could change the definition of ExecRowMark if this doesn't work, but
it would be far better to have a future-proof fix.

Piotr Stefaniak, some further hacking by me

Etsuro Fujita

Previously even if recovery_target_action was set to pause and
the recovery target was reached, the recovery could never be paused.
Because the setting of pause was *always* overridden with that of
shutdown unexpectedly. This override is valid and intentional
if hot_standby is not enabled because there is no way to resume
the paused recovery in this case and the setting of pause is
completely useless. But not if hot_standby is enabled.

This patch changes the code so that the setting of pause is overridden
with that of shutdown only when hot_standby is not enabled.

Bug reported by Andres Freund

In the spirit of the season.

Patch by CharSyam, plus a few more I spotted with grep.

Use "a" and "an" correctly, mostly in comments. Two error messages were
also fixed (they were just elogs, so no translation work required). Two
function comments in pg_proc.h were also fixed. Etsuro Fujita reported one
of these, but I found a lot more with grep.

Also fix a few other typos spotted while grepping for the a/an typos.
For example, "consists out of ..." -> "consists of ...". Plus a "though"/
"through" mixup reported by Euler Taveira.

Many of these typos were in old code, which would be nice to backpatch to
make future backpatching easier. But much of the code was new, and I didn't
feel like crafting separate patches for each branch. So no backpatching.

Revise description of CVE-2015-3166, in line with scaled-back patch.
Change release date.

Security: CVE-2015-3166

This reverts commit 16304a01, except
for its changes in src/port/snprintf.c; as well as commit
cac18a76 which is no longer needed.

Fujii Masao reported that the previous commit caused failures in psql on
OS X, since if one exits the pager program early while viewing a query
result, psql sees an EPIPE error from fprintf --- and the wrapper function
thought that was reason to panic.  (It's a bit surprising that the same
does not happen on Linux.)  Further discussion among the security list
concluded that the risk of other such failures was far too great, and
that the one-size-fits-all approach to error handling embodied in the
previous patch is unlikely to be workable.

This leaves us again exposed to the possibility of the type of failure
envisioned in CVE-2015-3166.  However, that failure mode is strictly
hypothetical at this point: there is no concrete reason to believe that
an attacker could trigger information disclosure through the supposed
mechanism.  In the first place, the attack surface is fairly limited,
since so much of what the backend does with format strings goes through
stringinfo.c or psprintf(), and those already had adequate defenses.
In the second place, even granting that an unprivileged attacker could
control the occurrence of ENOMEM with some precision, it's a stretch to
believe that he could induce it just where the target buffer contains some
valuable information.  So we concluded that the risk of non-hypothetical
problems induced by the patch greatly outweighs the security risks.
We will therefore revert, and instead undertake closer analysis to
identify specific calls that may need hardening, rather than attempt a
universal solution.

We have kept the portion of the previous patch that improved snprintf.c's
handling of errors when it calls the platform's sprintf().  That seems to
be an unalloyed improvement.

Security: CVE-2015-3166

Neither the deparsing of the new alias for INSERT's target table, nor of
the inference clause was supported. Also fixup a typo in an error
message.

Add regression tests to test those code paths.

Author: Peter Geoghegan

Defer lookup of opfamily and input type of a of a user specified opclass
until the optimizer selects among available unique indexes; and store
the opclass in the parse analyzed tree instead.  The primary reason for
doing this is that for rule deparsing it's easier to use the opclass
than the previous representation.

While at it also rename a variable in the inference code to better fit
it's purpose.

This is separate from the actual fixes for deparsing to make review
easier.

The point of the assertion is to ensure that the arrays allocated in stack
are large enough, but the check was one item short.

This won't matter in practice because MaxIndexTuplesPerPage is an
overestimate, so you can't have that many items on a page in reality.
But let's be tidy.

Spotted by Anastasia Lubennikova. Backpatch to all supported versions, like
the patch that added the assertion.

No index in template0 should have collation-dependent ordering, especially
not indexes on shared catalogs.  For most textual columns we avoid this
issue by using type "name" (which sorts per strcmp()).  However there are a
few indexed columns that we'd prefer to use "text" for, and for that, the
default opclass text_ops is unsafe.  Fortunately, text_pattern_ops is safe
(it sorts per memcmp()), and it has no real functional disadvantage for our
purposes.  So change the indexes on pg_seclabel.provider and
pg_shseclabel.provider to use text_pattern_ops.

In passing, also mark pg_replication_origin.roname as using
text_pattern_ops --- for some reason it was labeled varchar_pattern_ops
which is just wrong, even though it accidentally worked.

Add regression test queries to catch future errors of these kinds.

We still can't do anything about the misdeclared pg_seclabel and
pg_shseclabel indexes in back branches :-(

This reverts commit b82a7be6.  There
is a better (less invasive) way to fix it, which I will commit next.

The plain C string language name needs to be wrapped in makeString() so
that the parse tree is copyable.  This is detectable by
-DCOPY_PARSE_PLAN_TREES.  Add a test case for the COMMENT case.

Also make the quoting in the error messages more consistent.

discovered by Tom Lane