postgresql/src/tools/pginclude
Tomas Vondra 84adc8e20f pg_dump: Add support for zstd compression
Allow pg_dump to use the zstd compression, in addition to gzip/lz4. Bulk
of the new compression method is implemented in compress_zstd.{c,h},
covering the pg_dump compression APIs. The rest of the patch adds test
and makes various places aware of the new compression method.

The zstd library (which this patch relies on) supports multithreaded
compression since version 1.5. We however disallow that feature for now,
as it might interfere with parallel backups on platforms that rely on
threads (e.g. Windows). This can be improved / relaxed in the future.

This also fixes a minor issue in InitDiscoverCompressFileHandle(), which
was not updated to check if the file already has the .lz4 extension.

Adding zstd compression was originally proposed in 2020 (see the second
thread), but then was reworked to use the new compression API introduced
in e9960732a9. I've considered both threads when compiling the list of
reviewers.

Author: Justin Pryzby
Reviewed-by: Tomas Vondra, Jacob Champion, Andreas Karlsson
Discussion: https://postgr.es/m/20230224191840.GD1653@telsasoft.com
Discussion: https://postgr.es/m/20201221194924.GI30237@telsasoft.com
2023-04-05 21:39:33 +02:00
..
README Replace remaining uses of "whitelist". 2021-01-05 14:00:16 +13:00
cpluspluscheck pg_dump: Add support for zstd compression 2023-04-05 21:39:33 +02:00
headerscheck Tighten header pre-inclusions in headerscheck and cpluspluscheck. 2023-03-04 12:11:50 -05:00
pgcheckdefines Update copyright for 2023 2023-01-02 15:00:37 -05:00
pgcompinclude Lots of doc corrections. 2012-04-23 22:43:09 -04:00
pgdefine Improve method of avoiding fcinfo compile errors. 2011-09-01 14:16:13 -04:00
pgfixinclude Change references of CVS to .git. 2011-08-26 21:43:34 -04:00
pgrminclude Remove whitespace from end of lines 2012-05-15 22:19:41 +03:00

README

src/tools/pginclude/README

pginclude
=========

These utilities help clean up #include file usage.  They should be run
in this order so that the include files have the proper includes before
the C files are tested.

pgfixinclude	change #include's to <> or ""

pgcompinclude [-v]
		report which #include files can not compile on their own

pgrminclude [-v]
		remove extra #include's

pgcheckdefines
		check for #ifdef tests on symbols defined in files that
		weren't included --- this is a necessary sanity check on
		pgrminclude

pgdefine	create macro calls for all defines in the file (used by
		the above routines)

It is also a good idea to sort the pg-specific include files in
alphabetic order.  This is best done with a text editor. Typical usage
order would be:

	pgfixinclude
	sort include references
	run multiple times:
		pgcompinclude
		pgrminclude /src/include
	pgrminclude /
	pgcheckdefines

There is a complexity when modifying /src/include.  If include file 1
includes file 2, and file 2 includes file 3, then when file 1 is
processed, it needs only file 2, not file 3.  However, if later, include
file 2 is processed, and file 3 is not needed by file 2 and is removed,
file 1 might then need to include file 3.  For this reason, the
pgcompinclude and pgrminclude /src/include steps must be run several
times until all includes compile cleanly.

Also, tests should be done with configure settings of --enable-cassert
and EXEC_BACKEND on and off.  It is also wise to test a WIN32 compile.

Another tools that does a similar task is at:

	http://code.google.com/p/include-what-you-use/

An include file visualizer script is available at:

	http://archives.postgresql.org/pgsql-hackers/2011-09/msg00311.php


headerscheck
============

This script can be run to verify that all Postgres include files meet
the project convention that they will compile "standalone", that is
with no prerequisite headers other than postgres.h (or postgres_fe.h
or c.h, as appropriate).

A small number of header files are exempted from this requirement,
and are skipped by the headerscheck script.

The easy way to run the script is to say "make -s headerscheck" in
the top-level build directory after completing a build.  You should
have included "--with-perl --with-python" in your configure options,
else you're likely to get errors about related headers not being found.

A limitation of the current script is that it doesn't know which headers
are for frontend or backend, so it tests everything with postgres.h
as prerequisite, even if postgres_fe.h would be more appropriate.  Also
note that the contents of macros are not checked; this is intentional.


cpluspluscheck
==============

This script can be run to verify that all Postgres include files meet
the project convention that they will compile as C++ code.  Although
the project's coding language is C, some people write extensions in C++,
so it's helpful for include files to be C++-clean.

A small number of header files are exempted from this requirement,
and are skipped by the cpluspluscheck script.

The easy way to run the script is to say "make -s cpluspluscheck" in
the top-level build directory after completing a build.  You should
have included "--with-perl --with-python" in your configure options,
else you're likely to get errors about related headers not being found.

If you are using a non-g++-compatible C++ compiler, you may need to
override the script's CXXFLAGS setting by setting a suitable environment
value.

A limitation of the current script is that it doesn't know which headers
are for frontend or backend, so it tests everything with postgres.h
as prerequisite, even if postgres_fe.h would be more appropriate.  Also
note that the contents of macros are not checked; this is intentional.