If the compressed stream terminated early then the decompression process would get a flush request (NULL input buffer) since the filter was not marked as done. This could happen on a zero-length or truncated (i.e. invalid) compressed file.
Change the existing assertion to an error to catch this condition in production gracefully.
Adding a manifest to backup.info was migrated to C in 4e4d1f41 but deduplication of the references was missed leading to a reference for every file being added to backup.info.
Since the backup command is still using the Perl version of reconstruct this issue will not express unless 1) there is a backup missing from backup.info and 2) the expire command is run directly instead of running after backup as usual.
This unlikely combination of events means this is probably not a problem in the field.
Installing lcov 1.14 everywhere turned out to be a problem just as using 1.13 on Ubuntu 19.04 was.
Since we primarily use Ubuntu 18.04 for coverage testing and reporting, we definitely want to make sure that works. So, revert to using the default packaged lcov except when specified otherwise in VmTest.pm.
PostgreSQL minor version releases are also included since all containers have been rebuilt.
This should have been removed when the support for the option was removed in c7333190.
The option cannot be removed entirely because we don't want to error in the case where --force was specified but the stanza is valid.
Adding a dummy column which is always set by the P() macro allows a single macro to be used for parameters or no parameters without violating C's prohibition on the {} initializer.
-Wmissing-field-initializers remains disabled because it still gives wildly different results between versions of gcc.
Bug Fixes:
* Fix remote timeout in delta restore. When performing a delta restore on a largely unchanged cluster the remote could timeout if no files were fetched from the repository within protocol-timeout. Add keep-alives to prevent remote timeout. (Reported by James Sewell, Jens Wilke.)
* Fix handling of repeated HTTP headers. When HTTP headers are repeated they should be considered equivalent to a single comma-separated header rather than generating an error, which was the prior behavior. (Reported by donicrosby.)
Improvements:
* JSON output from the info command is no longer pretty-printed. Monitoring systems can more easily ingest the JSON without linefeeds. External tools such as jq can be used to pretty-print if desired. (Contributed by Cynthia Shang.)
* The check command is implemented entirely in C. (Contributed by Cynthia Shang.)
Documentation Improvements:
* Document how to contribute to pgBackRest. (Contributed by Cynthia Shang.)
* Document maximum version for auto-stop option. (Contributed by Brad Nicholson.)
Test Suite Improvements:
* Fix container test path being used when --vm=none. (Suggested by Stephen Frost.)
* Fix mismatched timezone in expect test. (Suggested by Stephen Frost.)
* Don't autogenerate embedded libc code by default. (Suggested by Stephen Frost.)
When HTTP headers are repeated they should be considered equivalent to a single comma-separated header rather than generating an error, which was the prior behavior.
Reported by donicrosby.
We had some problems with newer versions so had held off on updating. Those problems appear to have been resolved.
In addition, the --compat flag is no longer required. Prior versions of MinIO required all parts of a multi-part upload (except the last) to be of equal size. The --compat flag was introduced to restore the default S3 behavior. Now --compat is only required when ETag is being used for MD5 verification, which we don't do.
This documentation shows how to build a development environment on Ubuntu 19.04 and should work for other Debian-based distros.
Note that this document is not included in automated testing due to some unresolved issues with Docker in Docker on Travis CI. We'll address this in the future when we add contributing documentation to the website.
Mark all pre commands as skip so they won't be run again after the container is built.
Ensure that pre commands added to the container are run as the container user if they are not intended to run as root.
This is only needed when new code is added to the Perl C library, which is becoming rare as the migration progresses.
Also, the code will vary slightly based on the Perl version used for generation so for normal users it is just noise.
Suggested by Stephen Frost.
When performing a delta restore on a largely unchanged cluster the remote could timeout if no files were fetched from the repository within protocol-timeout.
Add keep-alives to prevent remote timeout.
Reported by James Sewell, Jens Wilke.
Note that building the manifest on each host has been temporarily removed.
This feature will likely be brought back as a non-default option (after the manifest code has been fully migrated to C) since it can be fairly expensive.
Three major changes were required to get this working:
1) Provide the path to pgbackrest in the build directory when running outside a container. Tests in a container will continue to install and run against /usr/bin/pgbackrest.
1) Set a per-test lock path so tests don't conflict on the default /tmp/pgbackrest path. Also set a per-test log-path while we are at it.
2) Use localhost instead of a custom host for TLS test connections. Tests in containers will continue to update /etc/hosts and use the custom host.
Add infrastructure and update harnessCfgLoad*() to get the correct exe and paths loaded for testing.
Since new tests are required to verify that running outside a container works, also rework the tests in Travis CI to provide coverage within a reasonable amount of time. Mainly, break up to doc tests by VM and run an abbreviated unit test suite on co6 and co7.
Features:
* PostgreSQL 12 support.
* Add info command set option for detailed text output. The additional details include databases that can be used for selective restore and a list of tablespaces and symlinks with their default destinations. (Contributed by Cynthia Shang. Suggested by Stephen Frost, ejberdecia.)
* Add standby restore type. This restore type automatically adds standby_mode=on to recovery.conf for PostgreSQL < 12 and creates standby.signal for PostgreSQL ≥ 12, creating a common interface between PostgreSQL versions. (Reviewed by Cynthia Shang.)
Improvements:
* The restore command is implemented entirely in C. (Reviewed by Cynthia Shang.)
Documentation Improvements:
* Document the relationship between db-timeout and protocol-timeout. (Contributed by Cynthia Shang. Suggested by James Chanco Jr.)
* Add documentation clarifications regarding standby repositories. (Contributed by Cynthia Shang.)
* Add FAQ for time-based Point-in-Time Recovery. (Contributed by Cynthia Shang.)
Recovery settings are now written into postgresql.auto.conf instead of recovery.conf. Existing recovery_target* settings will be commented out to help avoid conflicts.
A comment is added before recovery settings to identify them as written by pgBackRest since it is unclear how, in general, old settings will be removed.
recovery.signal and standby.signal are automatically created based on the recovery settings.
The additional details include databases that can be used for selective restore and a list of tablespaces and symlinks with their default destinations.
This information is not included in the JSON output because it requires reading the manifest which is too IO intensive to do for all manifests. We plan to include this information for JSON in a future release.
This restore type automatically adds standby_mode=on to recovery.conf.
This could be accomplished previously by setting --recovery-option=standby_mode=on but PostgreSQL 12 requires standby mode to be enabled by a special file named standby.signal.
The new restore type allows us to maintain a common interface between PostgreSQL versions.
We haven't had the time to complete this documentation and it has suffered bit rot.
This prevents us from building the docs on PostgreSQL >= 11 so just comment it all out until it can be updated.
For the most part this is a direct migration of the Perl code into C.
There is one important behavioral change with regard to how file permissions are handled. The Perl code tried to set ownership as it was in the manifest even when running as an unprivileged user. This usually just led to errors and frustration.
The C code works like this:
If a restore is run as a non-root user (the typical scenario) then all files restored will belong to the user/group executing pgBackRest. If existing files are not owned by the executing user/group then an error will result if the ownership cannot be updated to the executing user/group. In that case the file ownership will need to be updated by a privileged user before the restore can be retried.
If a restore is run as the root user then pgBackRest will attempt to recreate the ownership recorded in the manifest when the backup was made. Only user/group names are stored in the manifest so the same names must exist on the restore host for this to work. If the user/group name cannot be found locally then the user/group of the PostgreSQL data directory will be used and finally root if the data directory user/group cannot be mapped to a name.
Reviewed by Cynthia Shang.
The backup manifest stores a complete list of all files, links, and paths in a backup along with metadata such as checksums, sizes,
timestamps, etc. A list of databases is also included for selective restore.
The purpose of the manifest is to allow the restore command to confidently reconstruct the PostgreSQL data directory and ensure that
nothing is missing or corrupt. It is also useful for reporting, e.g. size of backup, backup time, etc.
For now, migrate enough functionality to implement the restore command.
Reviewed by Cynthia Shang.
These features finally make the ls command practical.
Currently the JSON contains only name, type, and size. We may add more fields in the future, but these seem like the minimum needed to be useful.
Connection reuse and pipelining are not the same thing and should not have been conflated.
Update comments and release notes to reflect the correct usage.
Info files required three copies in memory to be loaded (the original string, an ini representation, and the final info object). Not only was this memory inefficient but the Ini object does sequential scans when searching for keys making large files very slow to load.
This has not been an issue since archive.info and backup.info are very small, but it becomes a big deal when loading manifests with hundreds of thousands of files.
Instead of holding copies of the data in memory, use a callback to deliver the ini data directly to the object when loading. Use a similar method for save to avoid having an intermediate copy. Save is a bit complex because sections/keys must be written in alpha order or older versions of pgBackRest will not calculate the correct checksum.
Also move the load retry logic to helper functions rather than embedding it in the Info object. This allows for more flexibility in loading and ensures that stack traces will be available when developing unit tests.
Reviewed by Cynthia Shang.
286a106a updated the documentation to build pgBackRest as an unprivileged user, but the wget command was missed. This command is not actually run, just displayed, because the release is not yet available when the documentation is built.
Update the wget command to run as the local user.
Bug Fixes:
* Improve slow manifest build for very large quantities of tables/segments. (Reported by Jens Wilke.)
* Fix exclusions for special files. (Reported by CluelessTechnologist, Janis Puris, Rachid Broum.)
Improvements:
* The stanza-create/update/delete commands are implemented entirely in C. (Contributed by Cynthia Shang.)
* The start/stop commands are implemented entirely in C. (Contributed by Cynthia Shang.)
* Create log directories/files with 0750/0640 mode. (Suggested by Damiano Albani.)
Documentation Bug Fixes:
* Fix yum.p.o package being installed when custom package specified. (Reported by Joe Ayers, John Harvey.)
Documentation Improvements:
* Build pgBackRest as an unprivileged user. (Suggested by Laurenz Albe.)
The {[os-type-is-centos]} expression was missing parens which meant "and" expressions built on it would always evaluate true if the os-type was centos6.
Reported by Joe Ayers, John Harvey.
Prior to 2.16 the Perl manifest code would skip any file that began with a dot. This was not intentional but it allowed PostgreSQL socket files to be located in the data directory. The new C code in 2.16 did not have this unintentional exclusion so socket files in the data directory caused errors.
Worse, the file type error was being thrown before the exclusion check so there was really no way around the issue except to move the socket files out of the data directory.
Special file types (e.g. socket, pipe) will now be automatically skipped and a warning logged to notify the user of the exclusion. The warning can be suppressed with an explicit --exclude.
Reported by CluelessTechnologist, Janis Puris, Rachid Broum.
Putting the checksum at the beginning of the file made it impossible to stream the file out when saving. The entire file had to be held in memory while it was checksummed so the checksum could be written at the beginning.
Instead place the checksum at the end. This does not break the existing Perl or C code since the read is not order dependent.
There are no plans to improve the Perl code to take advantage of this change, but it will make the C implementation more efficient.
Reviewed by Cynthia Shang.
pgBackRest was being built by root in the documentation which is definitely not best practice.
Instead build as the unprivileged default container user. Sudo privileges are still required to install.
Suggested by Laurenz Albe.
storagePosixInfoList() processed each directory in a single memory context. If the directory contained hundreds of thousands of files processing became very slow due to the number of allocations.
Instead, reset the memory context every thousand files to minimize the number of allocations active at once, improving both speed and memory consumption.
Reported by Jens Wilke.
The log directories/files were being created with a mix of modes depending on whether they were created in C or Perl. In particular, the C code was creating log files with the execute bit set for the user and group which was just odd.
Standardize on 750/640 for both code paths.
Suggested by Damiano Albani.
The Perl versions remain because they are still being used by the Perl stanza commands. Once the stanza commands are migrated they can be removed.
Contributed by Cynthia Shang.
Bug Fixes:
* Retry S3 RequestTimeTooSkewed errors instead of immediately terminating. (Reported by sean0101n, Tim Garton, Jesper St John, Aleš Zelený.)
* Fix incorrect handling of transfer-encoding response to HEAD request. (Reported by Pavel Suderevsky.)
* Fix scoping violations exposed by optimizations in gcc 9. (Reported by Christian Lange, Ned T. Crigler.)
Features:
* Add repo-s3-port option for setting a non-standard S3 service port.
Improvements:
* The local command for backup is implemented entirely in C. (Contributed by David Steele, Cynthia Shang.)
* The check command is implemented partly in C. (Reviewed by Cynthia Shang.)
Implement switch WAL and archive check in C but leave the rest in Perl for now.
The main idea was to have some real integration tests for the new database code so the rest of the migration can wait.
Reviewed by Cynthia Shang.
Migrate functionality from the Perl Db module to C. For now this is just enough to implement the WAL switch check.
Add the dbGet() helper function to get Db objects easily.
Create macros in harnessPq to make writing pq scripts easier by grouping commonly used functions together.
Reviewed by Cynthia Shang.
The cause of this error seems to be that a failed request takes so long that a subsequent retry at the http level uses outdated headers.
We're not sure if pgBackRest it to blame here (in one case a kernel downgrade fixed it, in another case an incorrect network driver was the problem) so add retries to hopefully deal with the issue if it is not too persistent. If SSL_write() has long delays before reporting an error then this will obviously affect backup performance.
Reported by sean0101n, Tim Garton, Jesper St John, Aleš Zelený.
If this option is set then ports appended to repo-s3-endpoint or repo-s3-host will be ignored.
Setting this option explicitly may be the only way to use a bare ipv6 address with S3 (since multiple colons confuse the parser) but we plan to improve this in the future.
This direct interface to libpq allows simple queries to be run against PostgreSQL and supports timeouts.
Testing is performed using a shim that can use scripted responses to test all aspects of the client code. The shim will be very useful for testing backup scenarios on complex topologies.
Reviewed by Cynthia Shang.
The local process is now entirely migrated to C. Since all major I/O operations are performed in the local process, the vast majority of I/O is now performed in C.
Contributed by David Steele, Cynthia Shang.
The HTTP server can use either content-length or transfer-encoding to indicate that there is content in the response. HEAD requests do not include content but return all the same headers as GET. In the HEAD case we were ignoring content-length but not transfer-encoding which led to unexpected eof errors on AWS S3. Our test server, minio, uses content-length so this was not caught in integration testing.
Ignore all content for HEAD requests (no matter how it is reported) and add a unit test for transfer-encoding to prevent a regression.
Found by Pavel Suderevsky.
This analysis never produced anything but false positives (var might be NULL) but took over a minute per test run and added 600MB to the test container.
No new Perl code is being developed, so these tools are just taking up time and making migrations to newer platforms harder. There are only a few Perl tests remaining with full coverage so the coverage tool does not warn of loss of coverage in most cases.
Remove both tools and associated libraries.
gcc < 9 makes all compound literals function scope, even though the C spec requires them to be invalid outside the current scope. Since the compiler and valgrind were not enforcing this we had a few violations which caused problems in gcc >= 9.
Even though we are not quite ready to support gcc 9 officially, fix the scoping violations that currently exist in the codebase.
Reported by chrlange, Ned T. Crigler.
Maintaining the storage layer/drivers in two languages is burdensome. Since the integration tests require the Perl storage layer/drivers we'll need them even after the core code is migrated to C. Create an interface layer so the Perl code can be removed and new storage drivers/features introduced without adding Perl equivalents.
The goal is to move the integration tests to C so this interface will eventually be removed. That being the case, the interface was designed for maximum compatibility to ease the transition. The result looks a bit hacky but we'll improve it as needed until it can be retired.
Bug Fixes:
* Fix archive retention expiring too aggressively. (Fixed by Cynthia Shang. Reported by Mohamad El-Rifai.)
Improvements:
* The expire command is implemented entirely in C. (Contributed by Cynthia Shang.)
* The local command for restore is implemented entirely in C.
* Remove hard-coded PostgreSQL user so $PGUSER works. (Suggested by Julian Zhang, Janis Puris.)
* Honor configure --prefix option. (Suggested by Daniel Westermann.)
* Rename repo-s3-verify-ssl option to repo-s3-verify-tls. The new name is preferred because pgBackRest does not support any SSL protocol versions (they are all considered to be insecure). The old name will continue to be accepted.
Documentation Improvements:
* Add FAQ to the documentation. (Contributed by Cynthia Shang.)
* Use wal_level=replica in the documentation for PostgreSQL ≥ 9.6. (Suggested by Patrick McLaughlin.)
This variable needs to be replaced right before being used without being added to the cache since the host repo path will vary from system to system.
This is frankly a bit of a hack to get the documentation to build in the Debian packages for the upcoming release. We'll need to come up with something more flexible going forward.
The problem expressed when repo1-archive-retention-type was set to diff. In this case repo1-archive-retention ended up being effectively equal to one, which meant PITR recovery was only possible from the last backup. WAL required for consistency was still preserved for all backups.
This issue is not present in the C migration committed at 434cd832, which was written before this bug was reported. Even so, we wanted to note this issue in the release notes in case any other users have been affected.
Fixed by Cynthia Shang.
Reported by Mohamad El-Rifai.
This implementation duplicates the functionality of the Perl code but does so with different logic and includes full unit tests.
Along the way at least one bug was fixed, see issue #748.
Contributed by Cynthia Shang.
The PostgreSQL user was hard-coded to the OS user which libpq will automatically use if $PGUSER is not set, so this code was redundant and prevented $PGUSER from working when set.
Suggested by Julian Zhang, Janis Puris.
The tests and documentation have been using the core storage layer but soon that will depend entirely on the C library, creating a bootstrap problem (i.e. the storage layer will be needed to build the C library).
Create a simplified Posix storage layer to be used by documentation and the parts of the test code that build and execute the actual tests. The actual tests will still use the core storage driver so they can interact with any type of storage.
These names more accurately reflect what the functions do and follow the convention started in Info and InfoPg.
Also remove the ignoreMissing parameter since it was never used.
Contributed by Cynthia Shang.
The documentation was using wal_level=hot_standby which is a deprecated setting.
Also remove the reference to wal_level=archive since it is no longer supported and is not recommended for older versions.
Suggested by Patrick McLaughlin.
Allow commands to be skipped by default in the command help but still work if help is requested for the command directly. There may be other uses for the flag in the future.
Update help for ls now that it is exposed.
Allows listing repo paths/files from the command-line, to be used primarily for testing and debugging.
This command is internal-only so the interface may change at any time without notice.
The documentation was relying on a ScalityS3 container built for testing which wasn't very transparent. Instead, use the stock minio container and configure it in the documentation.
Also, install certificates and CA so that TLS verification can be enabled.
Since the CentOS 6/7 user guides were generated as a single page they did not get menus. Generate the entire site for each user guide so menus are included.
The release notes are generally a direct reflection of the git log. So, ease the burden of maintaining the release notes by using the git log to determine what needs to be added.
Currently only non-dev items are required to be matched to a git commit but the goal is to account for all commits.
The git history cache is generated from the git log but can be modified to correct typos and match the release notes as they evolve. The commit hash is used to identify commits that have already been added to the cache.
There's plenty more to do here. For instance, links to the commits for each release item should be added to the release notes.
The first paragraph should match the first line of the commit message as closely as possible. The following paragraphs add more information.
Release items have been updated back to 2.01.
The new name is preferred because pgBackRest does not support any SSL protocol versions (they are all considered to be insecure).
The old name will continue to be accepted.
This is just the part of restore run by the local helper processes, not the entire command.
Even so, various optimizations in the code (like pipelining and optimizations for zero-length files) should make the restore command faster on object stores.
Bug Fixes:
* Fix segfault when process-max > 8 for archive-push/archive-get. (Reported by Jens Wilke.)
Improvements:
* Bypass database checks when stanza-delete issued with force. (Contributed by Cynthia Shang. Suggested by hatifnatt.)
* Add configure script for improved multi-platform support.
Documentation Features:
* Add user guides for CentOS/RHEL 6/7.
It would be better if the documentation could be generated on multiple operating systems all in one go, but the doc system currently does not allow vars to be changed once they are set.
The solution is to run the docs for each required OS and stitch the documentation together. It's not pretty but it works and the automation in release.pl should at least make it easy to use.
The url for the menu item referring to the index (i.e. site root page) should use {[project-url-root]}.
This allows the url to be set to different values depending on the location of the index.
This report replaces the lcov report that was generated manually for each release.
The lcov report was overly verbose just to say that we have virtually 100% coverage.
There are currently no options with multiple alternate (deprecated) names so the code to render them in the help command could not be covered.
Remove the uncovered code and add an error when multiple alternate names are configured. It's not clear that the current code was handling this correctly, so it will need to be reviewed if it comes up again.
Pre-calculate the value used by logAny() to improve performance and make it more likely to be inlined.
Move IF_LOG_ANY() into LOG_INTERNAL() to simplify the macros and improve performance of LOG() and LOG_PID(). If the message has no chance of being logged there's no reason to call logInternal().
Rename logWill() to logAny() because it seems more intuitive.
The branch coverage exclusion rules were overly broad and included functions that ended in a capital letter, which disabled all coverage for the statement. Improve matching so that all characters in the name must be upper-case for a match.
Some macros with internal branches accepted parameters that might contain conditionals. This made it impossible to tell which branches belonged to which, and in any case an overzealous exclusion rule was ignoring all branches in such cases. Add the DEBUG_COVERAGE flag to build a modified version of the macros without any internal branches to be used for coverage testing. In most cases, the branches were optimizations (like checking logWill()) that improve production performance but are not needed for testing. In other cases, a parameter needed to be added to the underlying function to handle the branch during coverage testing.
Also tweak the coverage rules so that macros without conditionals are automatically excluded from branch coverage as long as they are not themselves a parameter.
Finally, update tests and code where missing coverage was exposed by these changes. Some code was updated to remove existing coverage exclusions when it was a simple change.
Call stackTraceTestStop()/stackTraceTestStart() once per block instead of with every param call. This was done to be cautious but is not necessary and slows down development.
These functions were never built into production so had no impact there.
Filters had different ideas about what "done" meant and this added complication to the group filter processing. For example, gzip decompression would detect end of stream and mark the filter as done before it had been flushed.
Improve the IoFilter interface to give a consistent definition of done across all filters, i.e. no filter can be done until it has started flushing no matter what the underlying driver reports. This removes quite a bit of tricky logic in the processing loop which tried to determine when a filter was "really" done.
Also improve management of the input buffers by pointing directly to the prior output buffer (or the caller's input) to eliminate loops that set/cleared these buffers.
If content was zero-length then the IO object was not created. This put the burden on the caller to test that the IO object existed before checking eof.
Instead, create an IO object even if it will immediately return eof. This has little cost and makes the calling code simpler.
Also add an explicit test for zero-length files in S3 and a few assertions.
The rules for when a C remote is required are getting complicated and will get worse when restoreFile() is migrated.
Instead, set the --c option when a C remote is required. This option will be removed when the remote is entirely implemented in C.
Most of the *Free() functions are pretty generic so add macros to make creating them as easy as possible.
Create a distinction between *Free() functions that the caller uses to free memory and callbacks that free third-party resources. There are a number of cases where a driver needs to free resources but does not need a normal *Free() because it is handled by the interface.
Add common/object.h for macros that make object maintenance easier. This pattern can also be used for many more object functions.
Rename memContextCallback() to memContextCallbackSet() to be more consistent with other parts of the code.
Free all context memory when an exception is thrown from a callback. Previously only the child contexts would be freed and this resulted in some allocations being lost. In practice this is probably not a big deal since the process will likely terminate shortly, but there may well be cases where that is not true.
Add GLUE() macro which is useful for creating identifiers.
Move MACRO_TO_STR() here and rename it STRINGIFY(). This appears to be the standard name for this type of macro and it is also an awesome name.
Remove "File" and "Driver" from object names so they are shorter and easier to keep consistent.
Also remove the "driver" directory so storage implementations are visible directly under "storage".
The function pointer casting used when creating drivers made changing interfaces difficult and led to slightly divergent driver implementations. Unit testing caught production-level errors but there were a lot of small issues and the process was harder than it should have been.
Use void pointers instead so that no casts are required. Introduce the THIS_VOID and THIS() macros to make dealing with void pointers a little safer.
Since we don't want to expose void pointers in header files, driver functions have been removed from the headers and the various driver objects return their interface type. This cuts down on accessor methods and the vast majority of those functions were not being used. Move functions that are still required to .intern.h.
Remove the special "C" crypto functions that were used in libc and instead use the standard interface.
Add bufDup() and bufNewUsedC().
Arrange bufNewC() params to match bufNewUsedC() since they have always seemed backward.
Fix bufHex() to only render the used portion of the buffer and fix some places where used was not being set correctly.
Use a union to make macro assignments for all legal values without casting. This is much more likely to catch bad assignments.
There is only one instance in the core code where this helps. It is mostly helpful in the tests.
There is an argument to be made that only THROW_SYS_ERROR*() variants should be used in the core code to improve test coverage. If so, that will be the subject of a future commit.
Some functions (e.g. getpwnam()/getgrnam()) will return an error but not set errno. In this case there's no use in appending strerror(), which will be "Success". This is confusing since an error has just been reported.
At least in the examples above, an error with no errno set just means "missing" and our current error message already conveys that.
The remote list was at most 9 (based on pg[1-8]-* max index) so anything over 8 wrote into unallocated memory.
The remote for the main process is (currently) stored in position zero so do the same for remotes started from locals, since there should only be one. The main process will need to start more remotes in the future which is why there is extra space.
Reported by Jens Wilke.
Use autoconf to provide a basic configure script. WITH_BACKTRACE is yet to be migrated to configure and the unit tests still use a custom Makefile.
Each C file must include "build.auto.conf" before all other includes and defines. This is enforced by test.pl for includes, but it won't detect incorrect define ordering.
Update packages to call configure and use standard flags to pass options.
Update RHEL repos that have changed upstream. Remove PostgreSQL 9.3 since the RHEL6/7 packages have disappeared.
Remove PostgreSQL versions from U12 that are still getting minor updates so the container does not need to be rebuilt.
LZ4 is included for future development, but this seems like a good time to add it to the containers.
