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2018-06-30Stamp HEAD as 12develAndrew Dunstan
Let the hacking begin ...
2018-06-29Make capitalization of term "OpenSSL" more consistentMichael Paquier
This includes code comments and documentation. No backpatch as this is cosmetic even if there are documentation changes which are user-facing. Author: Daniel Gustafsson Discussion: https://postgr.es/m/BB89928E-2BC7-489E-A5E4-6D204B3954CF@yesql.se
2018-06-25Translation updatesPeter Eisentraut
Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git Source-Git-Hash: 884f33d735870f94357820800840af3e93ff4628
2018-06-18Add PGTYPESchar_free() to avoid cross-module problems on Windows.Thomas Munro
On Windows, it is sometimes important for corresponding malloc() and free() calls to be made from the same DLL, since some build options can result in multiple allocators being active at the same time. For that reason we already provided PQfreemem(). This commit adds a similar function for freeing string results allocated by the pgtypes library. Author: Takayuki Tsunakawa Reviewed-by: Kyotaro Horiguchi Discussion: https://postgr.es/m/0A3221C70F24FB45833433255569204D1F8AD5D6%40G01JPEXMBYT05
2018-06-16Avoid unnecessary use of strncpy in a couple of places in ecpg.Tom Lane
Use of strncpy with a length limit based on the source, rather than the destination, is non-idiomatic and draws warnings from gcc 8. Replace with memcpy, which does exactly the same thing in these cases, but with less chance for confusion. Backpatch to all supported branches. Discussion: https://postgr.es/m/21789.1529170195@sss.pgh.pa.us
2018-05-27Don't fall off the end of perl functionsAndrew Dunstan
This complies with the perlcritic policy Subroutines::RequireFinalReturn, which is a severity 4 policy. Since we only currently check at severity level 5, the policy is raised to that level until we move to level 4 or lower, so that any new infringements will be caught. A small cosmetic piece of tidying of the pgperlcritic script is included. Mike Blackwell Discussion: https://postgr.es/m/CAESHdJpfFm_9wQnQ3koY3c91FoRQsO-fh02za9R3OEMndOn84A@mail.gmail.com
2018-05-21Translation updatesPeter Eisentraut
Source-Git-URL: git://git.postgresql.org/git/pgtranslation/messages.git Source-Git-Hash: 3a5a71cccad5c68e01008e9e3a4f06930197a05e
2018-05-20printf("%lf") is not portable, so omit the "l".Tom Lane
The "l" (ell) width spec means something in the corresponding scanf usage, but not here. While modern POSIX says that applying "l" to "f" and other floating format specs is a no-op, SUSv2 says it's undefined. Buildfarm experience says that some old compilers emit warnings about it, and at least one old stdio implementation (mingw's "ANSI" option) actually produces wrong answers and/or crashes. Discussion: https://postgr.es/m/21670.1526769114@sss.pgh.pa.us Discussion: https://postgr.es/m/c085e1da-0d64-1c15-242d-c921f32e0d5c@dunslane.net
2018-05-18Hot-fix ecpg regression test for missing ecpg_config.h inclusion.Tom Lane
I don't think this is really the best long-term answer, and in particular it doesn't fix the pre-existing hazard in sqltypes.h. But for the moment let's just try to make the buildfarm green again. Discussion: https://postgr.es/m/151935568942.1461.14623890240535309745@wrigleys.postgresql.org
2018-05-18Add some test coverage for ecpg's "long long" support.Tom Lane
This will only actually exercise the "long long" code paths on platforms where "long" is 32 bits --- otherwise, the SQL bigint type maps to plain "long", and we will test that code path instead. But that's probably sufficient coverage, and anyway we weren't testing either code path before. Dang Minh Huong, tweaked a bit by me Discussion: https://postgr.es/m/151935568942.1461.14623890240535309745@wrigleys.postgresql.org
2018-05-01Further -Wimplicit-fallthrough cleanup.Andres Freund
Tom's earlier commit in 41c912cad159 didn't update a few cases that are only encountered with the non-standard --with-llvm config flag. Additionally there's also one case that appears to be a deficiency in gcc's (up to trunk as of a few days ago) detection of "fallthrough" comments - changing the placement slightly fixes that. Author: Andres Freund Discussion: https://postgr.es/m/20180502003239.wfnqu7ekz7j7imm4@alap3.anarazel.de
2018-05-01Clean up warnings from -Wimplicit-fallthrough.Tom Lane
Recent gcc can warn about switch-case fall throughs that are not explicitly labeled as intentional. This seems like a good thing, so clean up the warnings exposed thereby by labeling all such cases with comments that gcc will recognize. In files that already had one or more suitable comments, I generally matched the existing style of those. Otherwise I went with /* FALLTHROUGH */, which is one of the spellings approved at the more-restrictive-than-default level -Wimplicit-fallthrough=4. (At the default level you can also spell it /* FALL ?THRU */, and it's not picky about case. What you can't do is include additional text in the same comment, so some existing comments containing versions of this aren't good enough.) Testing with gcc 8.0.1 (Fedora 28's current version), I found that I also had to put explicit "break"s after elog(ERROR) or ereport(ERROR); apparently, for this purpose gcc doesn't recognize that those don't return. That seems like possibly a gcc bug, but it's fine because in most places we did that anyway; so this amounts to a visit from the style police. Discussion: https://postgr.es/m/15083.1525207729@sss.pgh.pa.us
2018-04-27perltidy: Add option --nooutdent-long-commentsPeter Eisentraut
2018-04-27perltidy: Add option --nooutdent-long-quotesPeter Eisentraut
2018-04-26Post-feature-freeze pgindent run.Tom Lane
Discussion: https://postgr.es/m/15719.1523984266@sss.pgh.pa.us
2018-04-13In libpq, free any partial query result before collecting a server error.Tom Lane
We'd throw away the partial result anyway after parsing the error message. Throwing it away beforehand costs nothing and reduces the risk of out-of-memory failure. Also, at least in systems that behave like glibc/Linux, if the partial result was very large then the error PGresult would get allocated at high heap addresses, preventing the heap storage used by the partial result from being released to the OS until the error PGresult is freed. In psql >= 9.6, we hold onto the error PGresult until another error is received (for \errverbose), so that this behavior causes a seeming memory leak to persist for awhile, as in a recent complaint from Darafei Praliaskouski. This is a potential performance regression from older versions, justifying back-patching at least that far. But similar behavior may occur in other client applications, so it seems worth just back-patching to all supported branches. Discussion: https://postgr.es/m/CAC8Q8tJ=7cOkPePyAbJE_Pf691t8nDFhJp0KZxHvnq_uicfyVg@mail.gmail.com
2018-04-12Revert MERGE patchSimon Riggs
This reverts commits d204ef63776b8a00ca220adec23979091564e465, 83454e3c2b28141c0db01c7d2027e01040df5249 and a few more commits thereafter (complete list at the end) related to MERGE feature. While the feature was fully functional, with sufficient test coverage and necessary documentation, it was felt that some parts of the executor and parse-analyzer can use a different design and it wasn't possible to do that in the available time. So it was decided to revert the patch for PG11 and retry again in the future. Thanks again to all reviewers and bug reporters. List of commits reverted, in reverse chronological order: f1464c5380 Improve parse representation for MERGE ddb4158579 MERGE syntax diagram correction 530e69e59b Allow cpluspluscheck to pass by renaming variable 01b88b4df5 MERGE minor errata 3af7b2b0d4 MERGE fix variable warning in non-assert builds a5d86181ec MERGE INSERT allows only one VALUES clause 4b2d44031f MERGE post-commit review 4923550c20 Tab completion for MERGE aa3faa3c7a WITH support in MERGE 83454e3c2b New files for MERGE d204ef6377 MERGE SQL Command following SQL:2016 Author: Pavan Deolasee Reviewed-by: Michael Paquier
2018-04-08Switch client-side code to include catalog/pg_foo_d.h not pg_foo.h.Tom Lane
Everything of use to frontend code should now appear in the _d.h files, and making this change frees us from needing to worry about whether the catalog header files proper are frontend-safe. Remove src/interfaces/ecpg/ecpglib/pg_type.h entirely, as the previous commit reduced it to a confusingly-named wrapper around pg_type_d.h. In passing, make test_rls_hooks.c follow project convention of including our own files with #include "" not <>. Discussion: https://postgr.es/m/23690.1523031777@sss.pgh.pa.us
2018-04-08Replace our traditional initial-catalog-data format with a better design.Tom Lane
Historically, the initial catalog data to be installed during bootstrap has been written in DATA() lines in the catalog header files. This had lots of disadvantages: the format was badly underdocumented, it was very difficult to edit the data in any mechanized way, and due to the lack of any abstraction the data was verbose, hard to read/understand, and easy to get wrong. Hence, move this data into separate ".dat" files and represent it in a way that can easily be read and rewritten by Perl scripts. The new format is essentially "key => value" for each column; while it's a bit repetitive, explicit labeling of each value makes the data far more readable and less error-prone. Provide a way to abbreviate entries by omitting field values that match a specified default value for their column. This allows removal of a large amount of repetitive boilerplate and also lowers the barrier to adding new columns. Also teach genbki.pl how to translate symbolic OID references into numeric OIDs for more cases than just "regproc"-like pg_proc references. It can now do that for regprocedure-like references (thus solving the problem that regproc is ambiguous for overloaded functions), operators, types, opfamilies, opclasses, and access methods. Use this to turn nearly all OID cross-references in the initial data into symbolic form. This represents a very large step forward in readability and error resistance of the initial catalog data. It should also reduce the difficulty of renumbering OID assignments in uncommitted patches. Also, solve the longstanding problem that frontend code that would like to use OID macros and other information from the catalog headers often had difficulty with backend-only code in the headers. To do this, arrange for all generated macros, plus such other declarations as we deem fit, to be placed in "derived" header files that are safe for frontend inclusion. (Once clients migrate to using these pg_*_d.h headers, it will be possible to get rid of the pg_*_fn.h headers, which only exist to quarantine code away from clients. That is left for follow-on patches, however.) The now-automatically-generated macros include the Anum_xxx and Natts_xxx constants that we used to have to update by hand when adding or removing catalog columns. Replace the former manual method of generating OID macros for pg_type entries with an automatic method, ensuring that all built-in types have OID macros. (But note that this patch does not change the way that OID macros for pg_proc entries are built and used. It's not clear that making that match the other catalogs would be worth extra code churn.) Add SGML documentation explaining what the new data format is and how to work with it. Despite being a very large change in the catalog headers, there is no catversion bump here, because postgres.bki and related output files haven't changed at all. John Naylor, based on ideas from various people; review and minor additional coding by me; previous review by Alvaro Herrera Discussion: https://postgr.es/m/CAJVSVGWO48JbbwXkJz_yBFyGYW-M9YWxnPdxJBUosDC9ou_F0Q@mail.gmail.com
2018-04-03Prevent accidental linking of system-supplied copies of libpq.so etc.Tom Lane
We were being careless in some places about the order of -L switches in link command lines, such that -L switches referring to external directories could come before those referring to directories within the build tree. This made it possible to accidentally link a system-supplied library, for example /usr/lib/libpq.so, in place of the one built in the build tree. Hilarity ensued, the more so the older the system-supplied library is. To fix, break LDFLAGS into two parts, a sub-variable LDFLAGS_INTERNAL and the main LDFLAGS variable, both of which are "recursively expanded" so that they can be incrementally adjusted by different makefiles. Establish a policy that -L switches for directories in the build tree must always be added to LDFLAGS_INTERNAL, while -L switches for external directories must always be added to LDFLAGS. This is sufficient to ensure a safe search order. For simplicity, we typically also put -l switches for the respective libraries into those same variables. (Traditional make usage would have us put -l switches into LIBS, but cleaning that up is a project for another day, as there's no clear need for it.) This turns out to also require separating SHLIB_LINK into two variables, SHLIB_LINK and SHLIB_LINK_INTERNAL, with a similar rule about which switches go into which variable. And likewise for PG_LIBS. Although this change might appear to affect external users of pgxs.mk, I think it doesn't; they shouldn't have any need to touch the _INTERNAL variables. In passing, tweak src/common/Makefile so that the value of CPPFLAGS recorded in pg_config lacks "-DFRONTEND" and the recorded value of LDFLAGS lacks "-L../../../src/common". Both of those things are mistakes, apparently introduced during prior code rearrangements, as old versions of pg_config don't print them. In general we don't want anything that's specific to the src/common subdirectory to appear in those outputs. This is certainly a bug fix, but in view of the lack of field complaints, I'm unsure whether it's worth the risk of back-patching. In any case it seems wise to see what the buildfarm makes of it first. Discussion: https://postgr.es/m/25214.1522604295@sss.pgh.pa.us
2018-04-03MERGE SQL Command following SQL:2016Simon Riggs
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 other require multiple PL statements. e.g. 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 and partitioned tables, including column and row security enforcement, as well as support for row, statement and transition triggers. 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 statically from PL/pgSQL. MERGE does not yet support inheritance, write rules, RETURNING clauses, updatable views or foreign tables. MERGE follows SQL Standard per the most recent SQL:2016. Includes full tests and documentation, including full isolation tests to demonstrate the concurrent behavior. This version written from scratch in 2017 by Simon Riggs, using docs and tests originally written in 2009. Later work from Pavan Deolasee has been both complex and deep, leaving the lead author credit now in his hands. Extensive discussion of concurrency from Peter Geoghegan, with thanks for the time and effort contributed. Various issues reported via sqlsmith by Andreas Seltenreich Authors: Pavan Deolasee, Simon Riggs Reviewer: Peter Geoghegan, Amit Langote, Tomas Vondra, Simon Riggs Discussion: https://postgr.es/m/CANP8+jKitBSrB7oTgT9CY2i1ObfOt36z0XMraQc+Xrz8QB0nXA@mail.gmail.com https://postgr.es/m/CAH2-WzkJdBuxj9PO=2QaO9-3h3xGbQPZ34kJH=HukRekwM-GZg@mail.gmail.com
2018-04-02Revert "Modified files for MERGE"Simon Riggs
This reverts commit 354f13855e6381d288dfaa52bcd4f2cb0fd4a5eb.
2018-04-02Modified files for MERGESimon Riggs
2018-04-01Fix a boatload of typos in C comments.Tom Lane
Justin Pryzby Discussion: https://postgr.es/m/20180331105640.GK28454@telsasoft.com
2018-03-27libpq: PQhost to return active connected host or hostaddrPeter Eisentraut
Previously, PQhost didn't return the connected host details when the connection type was CHT_HOST_ADDRESS (i.e., via hostaddr). Instead, it returned the complete host connection parameter (which could contain multiple hosts) or the default host details, which was confusing and arguably incorrect. Change this to return the actually connected host or hostaddr irrespective of the connection type. When hostaddr but no host was specified, hostaddr is now returned. Never return the original host connection parameter, and document that PQhost cannot be relied on before the connection is established. PQport is similarly changed to always return the active connection port and never the original connection parameter. Author: Hari Babu <kommi.haribabu@gmail.com> Reviewed-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp> Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
2018-03-23Fix make rules that generate multiple output files.Tom Lane
For years, our makefiles have correctly observed that "there is no correct way to write a rule that generates two files". However, what we did is to provide empty rules that "generate" the secondary output files from the primary one, and that's not right either. Depending on the details of the creating process, the primary file might end up timestamped later than one or more secondary files, causing subsequent make runs to consider the secondary file(s) out of date. That's harmless in a plain build, since make will just re-execute the empty rule and nothing happens. But it's fatal in a VPATH build, since make will expect the secondary file to be rebuilt in the build directory. This would manifest as "file not found" failures during VPATH builds from tarballs, if we were ever unlucky enough to ship a tarball with apparently out-of-date secondary files. (It's not clear whether that has ever actually happened, but it definitely could.) To ensure that secondary output files have timestamps >= their primary's, change our makefile convention to be that we provide a "touch $@" action not an empty rule. Also, make sure that this rule actually gets invoked during a distprep run, else the hazard remains. It's been like this a long time, so back-patch to all supported branches. In HEAD, I skipped the changes in src/backend/catalog/Makefile, because those rules are due to get replaced soon in the bootstrap data format patch, and there seems no need to create a merge issue for that patch. If for some reason we fail to land that patch in v11, we'll need to back-fill the changes in that one makefile from v10. Discussion: https://postgr.es/m/18556.1521668179@sss.pgh.pa.us
2018-03-22Fix whitespacePeter Eisentraut
2018-03-20Attempt to fix build with unusual OpenSSL versionsPeter Eisentraut
Since e3bdb2d92600ed45bd46aaf48309a436a9628218, libpq failed to build on some platforms because they did not have SSL_clear_options(). Although mainline OpenSSL introduced SSL_clear_options() after SSL_OP_NO_COMPRESSION, so the code should have built fine, at least an old NetBSD version (build farm "coypu" NetBSD 5.1 gcc 4.1.3 PR-20080704 powerpc) has SSL_OP_NO_COMPRESSION but no SSL_clear_options(). So add a configure check for SSL_clear_options(). If we don't find it, skip the call. That means on such a platform one cannot *enable* SSL compression if the built-in default is off, but that seems an unlikely combination anyway and not very interesting in practice.
2018-03-17Fix closing of incorrectly named cursor.Michael Meskes
Patch by "Shinoda, Noriyoshi" <noriyoshi.shinoda@hpe.com>
2018-03-17Set libpq sslcompression to off by defaultPeter Eisentraut
Since SSL compression is no longer recommended, turn the default in libpq from on to off. OpenSSL 1.1.0 and many distribution packages already turn compression off by default, so such a server won't accept compression anyway. So this will mainly affect users of older OpenSSL installations. Also update the documentation to make clear that this setting is no longer recommended. Discussion: https://www.postgresql.org/message-id/flat/595cf3b1-4ffe-7f05-6f72-f72b7afa7993%402ndquadrant.com
2018-03-15Fix more format truncation issuesPeter Eisentraut
Fix the warnings created by the compiler warning options -Wformat-overflow=2 -Wformat-truncation=2, supported since GCC 7. This is a more aggressive variant of the fixes in 6275f5d28a1577563f53f2171689d4f890a46881, which GCC 7 warned about by default. The issues are all harmless, but some dubious coding patterns are cleaned up. One issue that is of external interest is that BGW_MAXLEN is increased from 64 to 96. Apparently, the old value would cause the bgw_name of logical replication workers to be truncated in some circumstances. But this doesn't actually add those warning options. It appears that the warnings depend a bit on compilation and optimization options, so it would be annoying to have to keep up with that. This is more of a once-in-a-while cleanup. Reviewed-by: Michael Paquier <michael@paquier.xyz>
2018-03-14Fixed compiler warnings in test case.Michael Meskes
2018-03-14Add Oracle like handling of char arrays.Michael Meskes
In some cases Oracle Pro*C handles char array differently than ECPG. This patch adds a Oracle compatibility mode to make ECPG behave like Pro*C. Patch by David Rader <davidr@openscg.com>
2018-03-14Fix double frees in ecpg.Michael Meskes
Patch by Patrick Krecker <patrick@judicata.com>
2018-03-13Set connection back to NULL after freeing it.Michael Meskes
Patch by Jeevan Ladhe <jeevan.ladhe@enterprisedb.com>
2018-03-13Move strtoint() to commonPeter Eisentraut
Several places used similar code to convert a string to an int, so take the function that we already had and make it globally available. Reviewed-by: Michael Paquier <michael@paquier.xyz>
2018-03-13Change internal integer representation of Value nodePeter Eisentraut
A Value node would store an integer as a long. This causes needless portability risks, as long can be of varying sizes. Change it to use int instead. All code using this was already careful to only store 32-bit values anyway. Reviewed-by: Michael Paquier <michael@paquier.xyz>
2018-03-03Trivial adjustments in preparation for bootstrap data conversion.Tom Lane
Rationalize a couple of macro names: * In catalog/pg_init_privs.h, rename Anum_pg_init_privs_privs to Anum_pg_init_privs_initprivs to match the column's actual name. * In ecpg, rename ZPBITOID to BITOID to match catalog/pg_type.h. This reduces reader confusion, and will allow us to generate these macros automatically in future. In catalog/pg_tablespace.h, fix the ordering of related DATA and #define lines to agree with how it's done elsewhere. This has no impact today, but simplifies life for the bootstrap data conversion scripts. John Naylor Discussion: https://postgr.es/m/CAJVSVGXnLH=BSo0x-aA818f=MyQqGS5nM-GDCWAMdnvQJTRC1A@mail.gmail.com
2018-01-30Refactor client-side SSL certificate checking codePeter Eisentraut
Separate the parts specific to the SSL library from the general logic. The previous code structure was open_client_SSL() calls verify_peer_name_matches_certificate() calls verify_peer_name_matches_certificate_name() calls wildcard_certificate_match() and was completely in fe-secure-openssl.c. The new structure is open_client_SSL() [openssl] calls pq_verify_peer_name_matches_certificate() [generic] calls pgtls_verify_peer_name_matches_certificate_guts() [openssl] calls openssl_verify_peer_name_matches_certificate_name() [openssl] calls pq_verify_peer_name_matches_certificate_name() [generic] calls wildcard_certificate_match() [generic] Move the generic functions into a new file fe-secure-common.c, so the calls generally go fe-connect.c -> fe-secure.c -> fe-secure-${impl}.c -> fe-secure-common.c, although there is a bit of back-and-forth between the last two. Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
2018-01-30Fix up references to scram-sha-256Peter Eisentraut
pg_hba_file_rules erroneously reported this as scram-sha256. Fix that. To avoid future errors and confusion, also adjust documentation links and internal symbols to have a separator between "sha" and "256". Reported-by: Christophe Courtois <christophe.courtois@dalibo.com> Author: Michael Paquier <michael.paquier@gmail.com>
2018-01-23Extract common bits from OpenSSL implementationPeter Eisentraut
Some things in be-secure-openssl.c and fe-secure-openssl.c were not actually specific to OpenSSL but could also be used by other implementations. In order to avoid copy-and-pasting, move some of that code to common files.
2018-01-23Move SSL API comments to header filesPeter Eisentraut
Move the documentation of the SSL API calls are supposed to do into the headers files, instead of keeping them in the files for the OpenSSL implementation. That way, they don't have to be duplicated or be inconsistent when other implementations are added.
2018-01-21Fix wording of "hostaddrs"Magnus Hagander
The field is still called "hostaddr", so make sure references use "hostaddr values" instead. Author: Michael Paquier <michael.paquier@gmail.com>
2018-01-13Cope with indicator arrays that do not have the correct length.Michael Meskes
Patch by: "Rader, David" <davidr@openscg.com>
2018-01-12Fix parsing of compatibility mode argument.Michael Meskes
Patch by Ashutosh Sharma <ashu.coek88@gmail.com>
2018-01-04Another attempt at fixing build with various OpenSSL versionsPeter Eisentraut
It seems we can't easily work around the lack of X509_get_signature_nid(), so revert the previous attempts and just disable the tls-server-end-point feature if we don't have it.
2018-01-04Add missing includesPeter Eisentraut
<openssl/x509.h> is necessary to look into the X509 struct, used by ac3ff8b1d8f98da38c53a701e6397931080a39cf.
2018-01-04Fix build with older OpenSSL versionsPeter Eisentraut
Apparently, X509_get_signature_nid() is only in fairly new OpenSSL versions, so use the lower-level interface it is built on instead.
2018-01-04Implement channel binding tls-server-end-point for SCRAMPeter Eisentraut
This adds a second standard channel binding type for SCRAM. It is mainly intended for third-party clients that cannot implement tls-unique, for example JDBC. Author: Michael Paquier <michael.paquier@gmail.com>
2018-01-04Refactor channel binding code to fetch cbind_data only when necessaryPeter Eisentraut
As things stand now, channel binding data is fetched from OpenSSL and saved into the SCRAM exchange context for any SSL connection attempted for a SCRAM authentication, resulting in data fetched but not used if no channel binding is used or if a different channel binding type is used than what the data is here for. Refactor the code in such a way that binding data is fetched from the SSL stack only when a specific channel binding is used for both the frontend and the backend. In order to achieve that, save the libpq connection context directly in the SCRAM exchange state, and add a dependency to SSL in the low-level SCRAM routines. This makes the interface in charge of initializing the SCRAM context cleaner as all its data comes from either PGconn* (for frontend) or Port* (for the backend). Author: Michael Paquier <michael.paquier@gmail.com>