removing an infrequently occurring race condition in Hot Standby.
An xid must be assigned before a lock appears in shared memory,
rather than immediately after, else GetRunningTransactionLocks()
may see InvalidTransactionId, causing assertion failures during
lock processing on standby.

Bug report and diagnosis by Fujii Masao, fix by me.

Per gripe from Andreas Scherbaum.

something that can be documented.

KaiGai Kohei, with a few changes by me.

The pg_fe_sendauth code might fail if it can't handle the authentication
request message type --- if so, ping should still say the server is up.

Basically, we want to distinguish all cases where the connection was
not made from those where it was.  A convenient proxy for this is to
see if we got a message with a SQLSTATE code back from the postmaster.
This presumes that the postmaster will always send us a SQLSTATE in
a failure message, which is true for 7.4 and later postmasters in
every case except fork failure.  (We could possibly complicate the
postmaster code to do something about that, but it seems not worth
the trouble, especially since pg_ctl's response for that case should
be to keep waiting anyway.)

If we did get a SQLSTATE from the postmaster, there are basically only
two cases, as per last week's discussion: ERRCODE_CANNOT_CONNECT_NOW
and everything else.  Any other error code implies that the postmaster
is in principle willing to accept connections, it just didn't like or
couldn't handle this particular request.  We want to make a special
case for ERRCODE_CANNOT_CONNECT_NOW so that "pg_ctl start -w" knows
it should keep waiting.

In passing, pick names for the enum constants that are a tad less
likely to present collision hazards in future.

Newly added code was supposing that "struct sockaddr_in" applies to IPv6.

1. Don't #include postgres.h in a frontend build.

2. Don't assume that the backend's symbol PGSQL_AF_INET6 has anything to do
with the constant that will be used by system library functions (because,
in point of fact, it usually doesn't).  Fortunately, PGSQL_AF_INET is equal
to AF_INET, so we can just cater for both sets of values in one case
construct without fear of conflict.

This adds support for changing the schema of a conversion, operator,
operator class, operator family, text search configuration, text search
dictionary, text search parser, or text search template.

Dimitri Fontaine, with assorted corrections and other kibitzing.

That macro should be attached to extern declarations, not actual
definitions of variables.

Most of the functions that execute XPath queries leaked the data structures
created by libxml2.  This memory would not be recovered until end of
session, so it mounts up pretty quickly in any serious use of the feature.
Per report from Pavel Stehule, though this isn't his patch.

Back-patch to all supported branches.

per Peter.

the OBJS lines from that file.

Cleanup where possible.

Makefile variable PGPORT, for clarity.

configure's LIBOBJS.  Should fix buildfarm failures.

status, including a status where the server is running but refuses a
postgres connection.

Have pg_ctl use this new function.  This fixes the case where pg_ctl
reports that the server is not running (cannot connect) but in fact it
is running.

Win32 buildfarm members.

After a SQL object is created, we provide an opportunity for security
or logging plugins to get control; for example, a security label provider
could use this to assign an initial security label to newly created
objects.  The basic infrastructure is (hopefully) reusable for other types
of events that might require similar treatment.

KaiGai Kohei, with minor adjustments.

except creating new connections.

Forcibly releasing all leftover buffer pins should be unnecessary now
that we have a robust ResourceOwner mechanism, and it significantly
increases the cost of process shutdown.  Instead, in an assert-enabled
build, assert that no pins are held; in a non-assert-enabled build, do
nothing.

reduce recovery time.

supplied, also print the IP address.  This allows IPv4 and IPv6 failures
to be distinguished.  Also useful when a hostname resolves to multiple
IP addresses.

Also, remove use of inet_ntoa() and use our own inet_net_ntop() in all
places, including in libpq, because it is thread-safe.

This commit adds columns amoppurpose and amopsortfamily to pg_amop, and
column amcanorderbyop to pg_am.  For the moment all the entries in
amcanorderbyop are "false", since the underlying support isn't there yet.

Also, extend the CREATE OPERATOR CLASS/ALTER OPERATOR FAMILY commands with
[ FOR SEARCH | FOR ORDER BY sort_operator_family ] clauses to allow the new
columns of pg_amop to be populated, and create pg_dump support for dumping
that information.

I also added some documentation, although it's perhaps a bit premature
given that the feature doesn't do anything useful yet.

Teodor Sigaev, Robert Haas, Tom Lane

Also, move index entries into the tables, closer to the function description,
for easier editing in the future.  Resort some tables to be more alphabetical.
Remove the entries for count, max, min, and sum in the tutorial area, because
that was felt to be confusing.

Thom Brown

This adds RESTRICT/CASCADE flags to ALTER TYPE ... ADD/DROP/ALTER/
RENAME ATTRIBUTE to control whether to alter typed tables as well.

Any flavor of ALTER <whatever> .. SET SCHEMA fails if (1) the object
is already in the new schema, (2) either the old or new schema is
a temp schema, or (3) either the old or new schema is the TOAST schema.

Extraced from a patch by Dimitri Fontaine, with additional hacking by me.

Currently, three conversion format specifiers are supported: %s for a
string, %L for an SQL literal, and %I for an SQL identifier.  The latter
two are deliberately designed not to overlap with what sprintf() already
supports, in case we want to add more of sprintf()'s functionality here
later.

Patch by Pavel Stehule, heavily revised by me.  Reviewed by Jeff Janes
and, in earlier versions, by Itagaki Takahiro and Tom Lane.