Complete the task begun in 9c0a0e2ed: we don't want to use the
abbreviation "deleg" for GSS delegation in any user-visible places.
(For consistency, this also changes most internal uses too.)
Abhijit Menon-Sen and Tom Lane
Discussion: https://postgr.es/m/949048.1684639317@sss.pgh.pa.us
Starting with OpenSSL 1.1.0 there is no need to call PQinitOpenSSL
or PQinitSSL to avoid duplicate initialization of OpenSSL. Add a
note to the documentation to explain this.
Backpatch to all supported versions as older OpenSSL versions are
equally likely to be used for all branches.
Reported-by: Sebastien Flaesch <sebastien.flaesch@4js.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/DBAP191MB12895BFFEC4B5FE0460D0F2FB0459@DBAP191MB1289.EURP191.PROD.OUTLOOK.COM
Backpatch-through: 11, all supported versions
This reverts commit 3d03b24c3 (Revert Add support for Kerberos
credential delegation) which was committed on the grounds of concern
about portability, but on further review and discussion, it's clear that
we are better off explicitly requiring MIT Kerberos as that appears to
be the only GSSAPI library currently that's under proper maintenance
and ongoing development. The API used for storing credentials was added
to MIT Kerberos over a decade ago while for the other libraries which
appear to be mainly based on Heimdal, which exists explicitly to be a
re-implementation of MIT Kerberos, the API never made it to a released
version (even though it was added to the Heimdal git repo over 5 years
ago..).
This post-feature-freeze change was approved by the RMT.
Discussion: https://postgr.es/m/ZDDO6jaESKaBgej0%40tamriel.snowman.net
This reverts commit 3d4fa227bc.
Per discussion and buildfarm, this depends on APIs that seem to not
be available on at least one platform (NetBSD). Should be certainly
possible to rework to be optional on that platform if necessary but bit
late for that at this point.
Discussion: https://postgr.es/m/3286097.1680922218@sss.pgh.pa.us
Support GSSAPI/Kerberos credentials being delegated to the server by a
client. With this, a user authenticating to PostgreSQL using Kerberos
(GSSAPI) credentials can choose to delegate their credentials to the
PostgreSQL server (which can choose to accept them, or not), allowing
the server to then use those delegated credentials to connect to
another service, such as with postgres_fdw or dblink or theoretically
any other service which is able to be authenticated using Kerberos.
Both postgres_fdw and dblink are changed to allow non-superuser
password-less connections but only when GSSAPI credentials have been
delegated to the server by the client and GSSAPI is used to
authenticate to the remote system.
Authors: Stephen Frost, Peifeng Qiu
Reviewed-By: David Christensen
Discussion: https://postgr.es/m/CO1PR05MB8023CC2CB575E0FAAD7DF4F8A8E29@CO1PR05MB8023.namprd05.prod.outlook.com
This adds a new option to libpq's sslrootcert, "system", which will load
the system trusted CA roots for certificate verification. This is a more
convenient way to achieve this than pointing to the system CA roots
manually since the location can differ by installation and be locally
adjusted by env vars in OpenSSL.
When sslrootcert is set to system, sslmode is forced to be verify-full
as weaker modes aren't providing much security for public CAs.
Changing the location of the system roots by setting environment vars is
not supported by LibreSSL so the tests will use a heuristic to determine
if the system being tested is LibreSSL or OpenSSL.
The workaround in .cirrus.yml is required to handle a strange interaction
between homebrew and the openssl@3 formula; hopefully this can be removed
in the near future.
The original patch was written by Thomas Habets, which was later revived
by Jacob Champion.
Author: Jacob Champion <jchampion@timescale.com>
Author: Thomas Habets <thomas@habets.se>
Reviewed-by: Jelte Fennema <postgres@jeltef.nl>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Reviewed-by: Magnus Hagander <magnus@hagander.net>
Discussion: https://www.postgresql.org/message-id/flat/CA%2BkHd%2BcJwCUxVb-Gj_0ptr3_KZPwi3%2B67vK6HnLFBK9MzuYrLA%40mail.gmail.com
This adds support for load balancing connections with libpq using a
connection parameter: load_balance_hosts=<string>. When setting the
param to random, hosts and addresses will be connected to in random
order. This then results in load balancing across these addresses and
hosts when multiple clients or frequent connection setups are used.
The randomization employed performs two levels of shuffling:
1. The given hosts are randomly shuffled, before resolving them
one-by-one.
2. Once a host its addresses get resolved, the returned addresses
are shuffled, before trying to connect to them one-by-one.
Author: Jelte Fennema <postgres@jeltef.nl>
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Reviewed-by: Michael Banck <mbanck@gmx.net>
Reviewed-by: Andrey Borodin <amborodin86@gmail.com>
Discussion: https://postgr.es/m/PR3PR83MB04768E2FF04818EEB2179949F7A69@PR3PR83MB0476.EURPRD83.prod.outlook.
The sslcertmode option controls whether the server is allowed and/or
required to request a certificate from the client. There are three
modes:
- "allow" is the default and follows the current behavior, where a
configured client certificate is sent if the server requests one
(via one of its default locations or sslcert). With the current
implementation, will happen whenever TLS is negotiated.
- "disable" causes the client to refuse to send a client certificate
even if sslcert is configured or if a client certificate is available in
one of its default locations.
- "require" causes the client to fail if a client certificate is never
sent and the server opens a connection anyway. This doesn't add any
additional security, since there is no guarantee that the server is
validating the certificate correctly, but it may helpful to troubleshoot
more complicated TLS setups.
sslcertmode=require requires SSL_CTX_set_cert_cb(), available since
OpenSSL 1.0.2. Note that LibreSSL does not include it.
Using a connection parameter different than require_auth has come up as
the simplest design because certificate authentication does not rely
directly on any of the AUTH_REQ_* codes, and one may want to require a
certificate to be sent in combination of a given authentication method,
like SCRAM-SHA-256.
TAP tests are added in src/test/ssl/, some of them relying on sslinfo to
check if a certificate has been set. These are compatible across all
the versions of OpenSSL supported on HEAD (currently down to 1.0.1).
Author: Jacob Champion
Reviewed-by: Aleksander Alekseev, Peter Eisentraut, David G. Johnston,
Michael Paquier
Discussion: https://postgr.es/m/9e5a8ccddb8355ea9fa4b75a1e3a9edc88a70cd3.camel@vmware.com
Support for SCM credential authentication has been removed in the
backend in 9.1, and libpq has kept some code to handle it for
compatibility.
Commit be4585b, that did the cleanup of the backend code, has done
so because the code was not really portable originally. And, as there
are likely little chances that this is used these days, this removes the
remaining code from libpq. An error will now be raised by libpq if
attempting to connect to a server that returns AUTH_REQ_SCM_CREDS,
instead.
References to SCM credential authentication are removed from the
protocol documentation. This removes some meson and configure checks.
Author: Michael Paquier
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/ZBLH8a4otfqgd6Kn@paquier.xyz
The new connection parameter require_auth allows a libpq client to
define a list of comma-separated acceptable authentication types for use
with the server. There is no negotiation: if the server does not
present one of the allowed authentication requests, the connection
attempt done by the client fails.
The following keywords can be defined in the list:
- password, for AUTH_REQ_PASSWORD.
- md5, for AUTH_REQ_MD5.
- gss, for AUTH_REQ_GSS[_CONT].
- sspi, for AUTH_REQ_SSPI and AUTH_REQ_GSS_CONT.
- scram-sha-256, for AUTH_REQ_SASL[_CONT|_FIN].
- creds, for AUTH_REQ_SCM_CREDS (perhaps this should be removed entirely
now).
- none, to control unauthenticated connections.
All the methods that can be defined in the list can be negated, like
"!password", in which case the server must NOT use the listed
authentication type. The special method "none" allows/disallows the use
of unauthenticated connections (but it does not govern transport-level
authentication via TLS or GSSAPI).
Internally, the patch logic is tied to check_expected_areq(), that was
used for channel_binding, ensuring that an incoming request is
compatible with conn->require_auth. It also introduces a new flag,
conn->client_finished_auth, which is set by various authentication
routines when the client side of the handshake is finished. This
signals to check_expected_areq() that an AUTH_REQ_OK from the server is
expected, and allows the client to complain if the server bypasses
authentication entirely, with for example the reception of a too-early
AUTH_REQ_OK message.
Regression tests are added in authentication TAP tests for all the
keywords supported (except "creds", because it is around only for
compatibility reasons). A new TAP script has been added for SSPI, as
there was no script dedicated to it yet. It relies on SSPI being the
default authentication method on Windows, as set by pg_regress.
Author: Jacob Champion
Reviewed-by: Peter Eisentraut, David G. Johnston, Michael Paquier
Discussion: https://postgr.es/m/9e5a8ccddb8355ea9fa4b75a1e3a9edc88a70cd3.camel@vmware.com
Commits f92944137 et al. made IsInTransactionBlock() set the
XACT_FLAGS_NEEDIMMEDIATECOMMIT flag before returning "false",
on the grounds that that kept its API promises equivalent to those of
PreventInTransactionBlock(). This turns out to be a bad idea though,
because it allows an ANALYZE in a pipelined series of commands to
cause an immediate commit, which is unexpected.
Furthermore, if we return "false" then we have another issue,
which is that ANALYZE will decide it's allowed to do internal
commit-and-start-transaction sequences, thus possibly unexpectedly
committing the effects of previous commands in the pipeline.
To fix the latter situation, invent another transaction state flag
XACT_FLAGS_PIPELINING, which explicitly records the fact that we
have executed some extended-protocol command and not yet seen a
commit for it. Then, require that flag to not be set before allowing
InTransactionBlock() to return "false".
Having done that, we can remove its setting of NEEDIMMEDIATECOMMIT
without fear of causing problems. This means that the API guarantees
of IsInTransactionBlock now diverge from PreventInTransactionBlock,
which is mildly annoying, but it seems OK given the very limited usage
of IsInTransactionBlock. (In any case, a caller preferring the old
behavior could always set NEEDIMMEDIATECOMMIT for itself.)
For consistency also require XACT_FLAGS_PIPELINING to not be set
in PreventInTransactionBlock. This too is meant to prevent commands
such as CREATE DATABASE from silently committing previous commands
in a pipeline.
Per report from Peter Eisentraut. As before, back-patch to all
supported branches (which sadly no longer includes v10).
Discussion: https://postgr.es/m/65a899dd-aebc-f667-1d0a-abb89ff3abf8@enterprisedb.com
Currently, PQsslAttributeNames() returns the same list of attribute
names regardless of its conn parameter. This patch changes it to
have behavior parallel to what 80a05679d installed for PQsslAttribute:
you get OpenSSL's attributes if conn is NULL or is an SSL-encrypted
connection, or an empty list if conn is a non-encrypted connection.
The point of this is to have sensible connection-dependent behavior
in case we ever support multiple SSL libraries. The behavior for
NULL can be defined as "the attributes for the default SSL library",
parallel to what PQsslAttribute(NULL, "library") does.
Since this is mostly just future-proofing, no back-patch.
Discussion: https://postgr.es/m/17625-fc47c78b7d71b534@postgresql.org
The compression parameter to PQsslAttribute has never returned the
compression method used, it has always returned "on" or "off since
it was added in commit 91fa7b4719. Backpatch through v10.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/B9EC60EC-F665-47E8-A221-398C76E382C9@yesql.se
Backpatch-through: v10
Commit ebc8b7d44 intended to change the behavior of
PQsslAttribute(NULL, "library"), but accidentally also changed
what happens with a non-NULL conn pointer. Undo that so that
only the intended behavior change happens. Clarify some
associated documentation.
Per bug #17625 from Heath Lord. Back-patch to v15.
Discussion: https://postgr.es/m/17625-fc47c78b7d71b534@postgresql.org
The extended query protocol implementation I added in commit
acb7e4eb6b has bugs when used in pipeline mode. Rather than spend
more time trying to fix it, remove that code and make the function rely
on simple query protocol only, meaning it can no longer be used in
pipeline mode.
Users can easily change their applications to use PQsendQueryParams
instead. We leave PQsendQuery in place for Postgres 14, just in case
somebody is using it and has not hit the mentioned bugs; but we should
recommend that it not be used.
Backpatch to 15.
Per bug report from Gabriele Varrazzo.
Discussion: https://postgr.es/m/CA+mi_8ZGSQNmW6-mk_iSR4JZB_LJ4ww3suOF+1vGNs3MrLsv4g@mail.gmail.com
Since HAVE_UNIX_SOCKETS is now defined unconditionally, remove the macro
and drop a small amount of dead code.
The last known systems not to have them (as far as I know at least) were
QNX, which we de-supported years ago, and Windows, which now has them.
If a new OS ever shows up with the POSIX sockets API but without working
AF_UNIX, it'll presumably still be able to compile the code, and fail at
runtime with an unsupported address family error. We might want to
consider adding a HINT that you should turn off the option to use it if
your network stack doesn't support it at that point, but it doesn't seem
worth making the relevant code conditional at compile time.
Also adjust a couple of places in the docs and comments that referred to
builds without Unix-domain sockets, since there aren't any. Windows
still gets a special mention in those places, though, because we don't
try to use them by default there yet.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
The documentation didn't specify the name of the per-user service file
on Windows, and extrapolating from the pattern used for other config
files gave the wrong answer. The fact that it isn't consistent with the
others sure seems like a bug, but it's far too late to change that now;
we'd just penalize people who worked it out in the past. So, simply
document the true state of affairs.
In passing, fix some gratuitous differences between the discussions
of the service file and the password file.
Julien Rouhaud, per question from Dominique Devienne.
Backpatch to all supported branches. I (tgl) also chose to back-patch
the part of commit ba356a397 that touched libpq.sgml's description of
the service file --- in hindsight, I'm not sure why I didn't do so at
the time, as it includes some fairly essential information.
Discussion: https://postgr.es/m/CAFCRh-_mdLrh8eYVzhRzu4c8bAFEBn=rwoHOmFJcQOTsCy5nig@mail.gmail.com
The current implementation supports exactly one IP address in a server
certificate's Common Name, which is brittle (the strings must match
exactly). This patch adds support for IPv4 and IPv6 addresses in a
server's Subject Alternative Names.
Per discussion on-list:
- If the client's expected host is an IP address, we allow fallback to
the Subject Common Name if an iPAddress SAN is not present, even if
a dNSName is present. This matches the behavior of NSS, in
violation of the relevant RFCs.
- We also, counter-intuitively, match IP addresses embedded in dNSName
SANs. From inspection this appears to have been the behavior since
the SAN matching feature was introduced in acd08d76.
- Unlike NSS, we don't map IPv4 to IPv6 addresses, or vice-versa.
Author: Jacob Champion <pchampion@vmware.com>
Co-authored-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Co-authored-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://www.postgresql.org/message-id/flat/9f5f20974cd3a4091a788cf7f00ab663d5fcdffe.camel@vmware.com
SSL has become the de facto term to mean an end-to-end encrypted channel
regardless of protocol used, even though the SSL protocol is deprecated.
Clarify what we mean with SSL in our documentation, especially for new
users who might be looking for TLS.
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/D4ABB281-6CFD-46C6-A4E0-8EC23A2977BC@yesql.se
Currently, libpq client code must have a connection handle
before it can query the "library" SSL attribute. This poses
problems if the client needs to know what SSL library is in
use before constructing a connection string.
Allow PQsslAttribute(NULL, "library") to return the library
in use -- currently, just "OpenSSL" or NULL. The new behavior
is announced with the LIBPQ_HAS_SSL_LIBRARY_DETECTION feature
macro, allowing clients to differentiate between a libpq that
was compiled without SSL support and a libpq that's just too
old to tell.
Author: Jacob Champion <pchampion@vmware.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/4c8b76ef434a96627170a31c3acd33cbfd6e41f1.camel@vmware.com
MERGE performs actions that modify rows in the target table using a
source table or query. MERGE provides a single SQL statement that can
conditionally INSERT/UPDATE/DELETE rows -- a task that would otherwise
require multiple PL statements. For example,
MERGE INTO target AS t
USING source AS s
ON t.tid = s.sid
WHEN MATCHED AND t.balance > s.delta THEN
UPDATE SET balance = t.balance - s.delta
WHEN MATCHED THEN
DELETE
WHEN NOT MATCHED AND s.delta > 0 THEN
INSERT VALUES (s.sid, s.delta)
WHEN NOT MATCHED THEN
DO NOTHING;
MERGE works with regular tables, partitioned tables and inheritance
hierarchies, including column and row security enforcement, as well as
support for row and statement triggers and transition tables therein.
MERGE is optimized for OLTP and is parameterizable, though also useful
for large scale ETL/ELT. MERGE is not intended to be used in preference
to existing single SQL commands for INSERT, UPDATE or DELETE since there
is some overhead. MERGE can be used from PL/pgSQL.
MERGE does not support targetting updatable views or foreign tables, and
RETURNING clauses are not allowed either. These limitations are likely
fixable with sufficient effort. Rewrite rules are also not supported,
but it's not clear that we'd want to support them.
Author: Pavan Deolasee <pavan.deolasee@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Simon Riggs <simon.riggs@enterprisedb.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions)
Reviewed-by: Peter Geoghegan <pg@bowt.ie> (earlier versions)
Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier versions)
Reviewed-by: Japin Li <japinli@hotmail.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Discussion: https://postgr.es/m/CANP8+jKitBSrB7oTgT9CY2i1ObfOt36z0XMraQc+Xrz8QB0nXA@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzkJdBuxj9PO=2QaO9-3h3xGbQPZ34kJH=HukRekwM-GZg@mail.gmail.com
Discussion: https://postgr.es/m/20201231134736.GA25392@alvherre.pgsql
As currently implemented, failure of a PGEVT_CONNRESET callback
forces the PGconn into the CONNECTION_BAD state (without closing
the socket, which is inconsistent with other failure paths), and
prevents later callbacks from being called. This seems highly
questionable, and indeed is questioned by comments in the source.
Instead, let's just ignore the result value of PGEVT_CONNRESET
calls. Like the preceding commit, this converts event callbacks
into "pure observers" that cannot affect libpq's processing logic.
Discussion: https://postgr.es/m/3185105.1644960083@sss.pgh.pa.us
As currently implemented, failure of a PGEVT_RESULTCREATE callback
causes the PGresult to be converted to an error result. This is
intellectually inconsistent (shouldn't a failing callback likewise
prevent creation of the error result? what about side-effects on the
behavior seen by other event procs? why does PQfireResultCreateEvents
act differently from PQgetResult?), but more importantly it destroys
any promises we might wish to make about the behavior of libpq in
nontrivial operating modes, such as pipeline mode. For example,
it's not possible to promise that PGRES_PIPELINE_SYNC results will
be returned if an event callback fails on those. With this
definition, expecting applications to behave sanely in the face of
possibly-failing callbacks seems like a very big lift.
Hence, redefine the result of a callback failure as being simply
that that event procedure won't be called any more for this PGresult
(which was true already). Event procedures can still signal failure
back to the application through out-of-band mechanisms, for example
via their passthrough arguments.
Similarly, don't let failure of a PGEVT_RESULTCOPY callback prevent
PQcopyResult from succeeding. That definition allowed a misbehaving
event proc to break single-row mode (our sole internal use of
PQcopyResult), and it probably had equally deleterious effects for
outside uses.
Discussion: https://postgr.es/m/3185105.1644960083@sss.pgh.pa.us
If connectivity to the server has been lost or become flaky, the
user might well try to send a query cancel. It's highly annoying
if PQcancel hangs up in such a case, but that's exactly what's likely
to happen. To ameliorate this problem, apply the PGconn's
tcp_user_timeout and keepalives settings to the TCP connection used
to send the cancel. This should be safe on Unix machines, since POSIX
specifies that setsockopt() is async-signal-safe. We are guessing
that WSAIoctl(SIO_KEEPALIVE_VALS) is similarly safe on Windows.
(Note that at least in psql and our other frontend programs, there's
no safety issue involved anyway, since we run PQcancel in its own
thread rather than in a signal handler.)
Most of the value here comes from the expectation that tcp_user_timeout
will be applied as a connection timeout. That appears to happen on
Linux, even though its tcp(7) man page claims differently. The
keepalive options probably won't help much, but as long as we can
apply them for not much code, we might as well.
Jelte Fennema, reviewed by Fujii Masao and myself
Discussion: https://postgr.es/m/AM5PR83MB017870DE81FC84D5E21E9D1EF7AA9@AM5PR83MB0178.EURPRD83.prod.outlook.com
ssl_crl_file and ssl_crl_dir are both used to for client certificate
revocation, not server certificates. The description for the params
could be easily misread to mean the opposite however, as evidenced
by the bugreport leading to this fix. Similarly, expand sslcrl and
and sslcrldir to explicitly mention server certificates. While there
also mention sslcrldir where previously only sslcrl was discussed.
Backpatch down to v10, with the CRL dir fixes down to 14 where they
were introduced.
Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/20211202.135441.590555657708629486.horikyota.ntt@gmail.com
Discussion: https://postgr.es/m/CABWY_HCBUCjY1EJHrEGePGEaSZ5b29apgTohCyygtsqe_ySYng@mail.gmail.com
Backpatch-through: 10
The check for sslsni only checked for existence of the parameter
but not for the actual value of the param. This meant that the
SNI extension was always turned on. Fix by inspecting the value
of sslsni and only activate the SNI extension iff sslsni has been
enabled. Also update the docs to be more in line with how other
boolean params are documented.
Backpatch to 14 where sslsni was first implemented.
Reviewed-by: Tom Lane
Backpatch-through: 14, where sslni was added
When sending queries in pipeline mode, we were careless about leaving
the connection in the right state so that PQgetResult would behave
correctly; trying to read further results after sending a query after
having read a result with an error would sometimes hang. Fix by
ensuring internal libpq state is changed properly. All the state
changes were being done by the callers of pqAppendCmdQueueEntry(); it
would have become too repetitious to have this logic in each of them, so
instead put it all in that function and relieve callers of the
responsibility.
Add a test to verify this case. Without the code fix, this new test
hangs sometimes.
Also, document that PQisBusy() would return false when no queries are
pending result. This is not intuitively obvious, and NULL would be
obtained by calling PQgetResult() at that point, which is confusing.
Wording by Boris Kolpackov.
In passing, fix bogus use of "false" to mean "0", per Ranier Vilela.
Backpatch to 14.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Boris Kolpackov <boris@codesynthesis.com>
Discussion: https://postgr.es/m/boris.20210624103805@codesynthesis.com
This new libpq function allows the application to send an 'H' message,
which instructs the server to flush its outgoing buffer.
This hasn't been needed so far because the Sync message already requests
a buffer; and I failed to realize that this was needed in pipeline mode
because PQpipelineSync also causes the buffer to be flushed. However,
sometimes it is useful to request a flush without establishing a
synchronization point.
Backpatch to 14, where pipeline mode was introduced in libpq.
Reported-by: Boris Kolpackov <boris@codesynthesis.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/202106252350.t76x73nt643j@alvherre.pgsql
This adds MITM and SNI as acronyms, as the documentation already had
them marked up with <acronym>.
While on it, make sure to spell man-in-the-middle with dashes
consistently, and add acronyms for those new terms where appropriate.
Author: Daniel Gustafsson
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CE12DD5C-4BB3-4166-BC9A-39779568734C@yesql.se
We have a dozen PQset*() functions. PQresultSetInstanceData() and this
were the libpq setter functions having a different word order. Adopt
the majority word order.
Reviewed by Alvaro Herrera and Robert Haas, though this choice of name
was not unanimous.
Discussion: https://postgr.es/m/20210605060555.GA216695@rfd.leadboat.com
We've accumulated quite a mix of instances of "an SQL" and "a SQL" in the
documents. It would be good to be a bit more consistent with these.
The most recent version of the SQL standard I looked at seems to prefer
"an SQL". That seems like a good lead to follow, so here we change all
instances of "a SQL" to become "an SQL". Most instances correctly use
"an SQL" already, so it also makes sense to use the dominant variation in
order to minimise churn.
Additionally, there were some other abbreviations that needed to be
adjusted. FSM, SSPI, SRF and a few others. Also fix some pronounceable,
abbreviations to use "a" instead of "an". For example, "a SASL" instead
of "an SASL".
Here I've only adjusted the documents and error messages. Many others
still exist in source code comments. Translator hint comments seem to be
the biggest culprit. It currently does not seem worth the churn to change
these.
Discussion: https://postgr.es/m/CAApHDvpML27UqFXnrYO1MJddsKVMQoiZisPvsAGhKE_tsKXquw%40mail.gmail.com
This was missing in the section dedicated to the supported environment
variables of libpq. Oversight in f5465fa.
Reviewed-by: Daniel Gustafsson, Kyotaro Horiguchi
Discussion: https://postgr.es/m/YLhI0mLoRkY3u4Wj@paquier.xyz
Clarify libpq.sgml's description of service file locations and
semantics. Avoid use of backtick'ed pg_config calls to describe
paths; that doesn't work on Windows, and even on Unix it's an
idiom that not all readers may be instantly familiar with.
Don't overspecify the locations of include files, instead writing
only as much as you'd use in #include directives. The previous text
in these places was incorrect for some installations, depending on
where "postgresql" is in the install path.
Our convention for referencing the user's home directory seems
to be "~", so change the one place that spelled it "$HOME".
install-windows.sgml follows the platform convention of spelling
file paths with "\", so change the one place that used "/".
Haiying Tang and Tom Lane
Discussion: https://postgr.es/m/162149020918.26174.7150424047314144297@wrigleys.postgresql.org
Mention specifically that you can't call aggregates, window functions,
or procedures this way (the inability to call SRFs was already
mentioned).
Also, the claim that PQfn doesn't support NULL arguments or results
has been a lie since we invented protocol 3.0. Not sure why this
text was never updated for that, but do it now.
Discussion: https://postgr.es/m/2039442.1615317309@sss.pgh.pa.us
Tom Lane
Fujii Masao
Daniel Gustafsson
Stephen Frost
Michael Paquier
Heikki Linnakangas
Peter Eisentraut
Alvaro Herrera
Thomas Munro
Noah Misch
David Rowley
Bruce Momjian