4 Commits (3b6728910ace14c64ffa43b538a84508f4fe6408)

Author	SHA1	Message	Date
Tom Lane	d51924be88	Convert contrib/hstore_plpython to not use direct linking to other modules. ... Previously, on most platforms, we allowed hstore_plpython's references to hstore and plpython to be unresolved symbols at link time, trusting the dynamic linker to resolve them when the module is loaded. This has a number of problems, the worst being that the dynamic linker does not know where the references come from and can do nothing but fail if those other modules haven't been loaded. We've more or less gotten away with that for the limited use-case of datatype transform modules, but even there, it requires some awkward hacks, most recently commit 83c249200. Instead, let's not treat these references as linker-resolvable at all, but use function pointers that are manually filled in by the module's _PG_init function. There are few enough contact points that this doesn't seem unmaintainable, at least for these use-cases. (Note that the same technique wouldn't work at all for decoupling from libpython itself, but fortunately that's just a standard shared library and can be linked to normally.) This is an initial patch that just converts hstore_plpython. If the buildfarm doesn't find any fatal problems, I'll work on the other transform modules soon. Tom Lane, per an idea of Andres Freund's. Discussion: <2652.1475512158@sss.pgh.pa.us>	9 years ago
Tom Lane	5484c0a980	Minor fixes in contrib installation scripts. ... Extension scripts should never use CREATE OR REPLACE for initial object creation. If there is a collision with a pre-existing (probably user-created) object, we want extension installation to fail, not silently overwrite the user's object. Bloom and sslinfo both violated this precept. Also fix a number of scripts that had no standard header (the file name comment and the \echo...\quit guard). Probably the \echo...\quit hack is less important now than it was in 9.1 days, but that doesn't mean that individual extensions get to choose whether to use it or not. And fix a couple of evident copy-and-pasteos in file name comments. No need for back-patch: the REPLACE bugs are both new in 9.6, and the rest of this is pretty much cosmetic. Andreas Karlsson and Tom Lane	9 years ago
Tom Lane	fb6fcbd33f	Use LOAD not actual code execution to pull in plpython library. ... Commit 866566a690 is insufficient to prevent dump/reload failures when using transform modules in a database with both plpython2 and plpython3 installed. The reason is that the transform extension scripts use DO blocks as a mechanism to pull in the libpython library before creating the transform function. It's necessary to preload the library because the dynamic loader won't do it for us on every platform, leading to "unresolved symbol" failures when the transform library is loaded. But it's *not* necessary to execute Python code, and doing so will provoke a multiple-Pythons-are-loaded error even after the preceding commit. To fix, use LOAD instead of a DO block. That requires superuser privilege, but creation of a C function does anyway. It also embeds knowledge of the underlying library name for each PL language; but that's wired into the initdb-time contents of pg_pltemplate too, so that doesn't seem like a large problem either. Note that CREATE TRANSFORM as such doesn't call the language module at all. Per a report from Paul Jones. Back-patch to 9.5 where transform modules were introduced.	10 years ago
Peter Eisentraut	cac7658205	Add transforms feature ... This provides a mechanism for specifying conversions between SQL data types and procedural languages. As examples, there are transforms for hstore and ltree for PL/Perl and PL/Python. reviews by Pavel Stěhule and Andres Freund	11 years ago