When we try to set the zstd compression level either on the client
or on the server, check for errors.
For any algorithm, on the client side, don't try to set the compression
level unless the user specified one. This was visibly broken for
zstd, which managed to set -1 rather than 0 in this case, but tidy
up the code for the other methods, too.
On the client side, if we fail to create a ZSTD_CCtx, exit after
reporting the error. Otherwise we'll dereference a null pointer.
Patch by me, reviewed by Dipesh Pandit.
Discussion: http://postgr.es/m/CA+TgmoZK3zLQUCGi1h4XZw4jHiAWtcACc+GsdJR1_Mc19jUjXA@mail.gmail.com
There are more compression parameters that can be specified than just
an integer compression level, so rename the new COMPRESSION_LEVEL
option to COMPRESSION_DETAIL before it gets released. Introduce a
flexible syntax for that option to allow arbitrary options to be
specified without needing to adjust the main replication grammar,
and common code to parse it that is shared between the client and
the server.
This commit doesn't actually add any new compression parameters,
so the only user-visible change is that you can now type something
like pg_basebackup --compress gzip:level=5 instead of writing just
pg_basebackup --compress gzip:5. However, it should make it easy to
add new options. If for example gzip starts offering fries, we can
support pg_basebackup --compress gzip:level=5,fries=true for the
benefit of users who want fries with that.
Along the way, this fixes a few things in pg_basebackup so that the
pg_basebackup can be used with a server-side compression algorithm
that pg_basebackup itself does not understand. For example,
pg_basebackup --compress server-lz4 could still succeed even if
only the server and not the client has LZ4 support, provided that
the other options to pg_basebackup don't require the client to
decompress the archive.
Patch by me. Reviewed by Justin Pryzby and Dagfinn Ilmari Mannsåker.
Discussion: http://postgr.es/m/CA+TgmoYvpetyRAbbg1M8b3-iHsaN4nsgmWPjOENu5-doHuJ7fA@mail.gmail.com
These tests were added recently, but older code tests USE_LZ4 rathr
than HAVE_LIBLZ4, so let's follow the established precedent. It
also seems more consistent with the intent of the configure tests,
since I think that the USE_* symbols are intended to correspond to
what the user requested, and the HAVE_* symbols to what configure
found while probing.
Discussion: http://postgr.es/m/CA+Tgmoap+hTD2-QNPJLH4tffeFE8MX5+xkbFKMU3FKBy=ZSNKA@mail.gmail.com
Both client-side compression and server-side compression are now
supported for zstd. In addition, a backup compressed by the server
using zstd can now be decompressed by the client in order to
accommodate the use of -Fp.
Jeevan Ladhe, with some edits by me.
Discussion: http://postgr.es/m/CA+Tgmobyzfbz=gyze2_LL1ZumZunmaEKbHQxjrFkOR7APZGu-g@mail.gmail.com
Robert Haas