b9b610577d
contrib/pgcrypto mishandled the case where deflate() does not consume all of the offered input on the first try. It reset the next_in pointer to the start of the input instead of leaving it alone, causing the wrong data to be fed to the next deflate() call. This has been broken since pgcrypto was committed. The reason for the lack of complaints seems to be that it's fairly hard to get stock zlib to not consume all the input, so long as the output buffer is big enough (which it normally would be in pgcrypto's usage; AFAICT the input is always going to be packetized into packets no larger than ZIP_OUT_BUF). However, IBM's zlibNX implementation for AIX evidently will do it in some cases. I did not add a test case for this, because I couldn't find one that would fail with stock zlib. When we put back the test case for bug #16476, that will cover the zlibNX situation well enough. While here, write deflate()'s second argument as Z_NO_FLUSH per its API spec, instead of hard-wiring the value zero. Per buildfarm results and subsequent investigation. Discussion: https://postgr.es/m/16476-692ef7b84e5fb893@postgresql.org
The PostgreSQL contrib tree
---------------------------
This subtree contains porting tools, analysis utilities, and plug-in
features that are not part of the core PostgreSQL system, mainly
because they address a limited audience or are too experimental to be
part of the main source tree. This does not preclude their
usefulness.
User documentation for each module appears in the main SGML
documentation.
When building from the source distribution, these modules are not
built automatically, unless you build the "world" target. You can
also build and install them all by running "make all" and "make
install" in this directory; or to build and install just one selected
module, do the same in that module's subdirectory.
Some directories supply new user-defined functions, operators, or
types. To make use of one of these modules, after you have installed
the code you need to register the new SQL objects in the database
system by executing a CREATE EXTENSION command. In a fresh database,
you can simply do
CREATE EXTENSION module_name;
See the PostgreSQL documentation for more information about this
procedure.