Re: server-side extension in c++

Craig Ringer wrote:
> Igor wrote:
> > Hi All,
> >
> > Is there an easy way to add c++ files to my simple pgsql module ? My Makefile
> > is as follows -
> >
> > ===
> > MODULES = pg_uservars
> > DATA_built = pg_uservars.sql
> > PGXS := $(shell pg_config --pgxs)
> > include $(PGXS)
> > ===
> >
> > I've got "pg_uservars.c" and "hv.cc" and I'd like to compile hv.cc via g++.
> > I'm aware of c++ name [de]mangling, just looking if there's a standard way of
> > using C++ when it comes to pgxs.
>
> It should "just work". Simply make sure to follow the usual rules for
> calling into C++ code from C and vice versa:
>
> - Use "extern C" linkage for all functions that must be accessible by
> dlopen(), and preferably also for any functions that you might take
> a function pointer to and pass to C code
>
> - Never return new()'d memory that might be free()'d by the C code; use
> malloc()
>
> - Never delete() memory that was malloc()'d by the C code; use free()
>
> - Never let an exception propagate into the C code; use a catch-all
> block at the top level of all "extern C" functions
>
> ... and probably other things I've missed.

That is great new information. I have created a new documentation
section called "Using C++ for Extensibility", and listed you as the
author in the CVS commit; patch attached. Thanks.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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