I have just finished porting FreeAdhocUDF to MacOSX and sent the Makefiles, code, plus 32bit UDF libraries for Firebird 1.5.5 and Firebird 2.x to the FreeAdhocUDF types to be included in the distribution.
Issues that you might need to be aware of.
1. In Firebird 1.5.5 we don't ship libib_util.dylib, and even if we did you wouldn't be able to link to it. It seems that Firebird 1.5.5's installer doesn't copy the library to the Framework. This has now been fixed for the next release. Secondly the library was being built as a bundle. All Firebird UDF's need to be created as bundles to work on MacOSX. You can't link a bundle to a bundle. This has also been fixed.
2. In Firebird 1.5.5 you must remove any extension from the UDF library (e.g dylib) to get it to work. So for example FreeAdhocUDF.dylib needs to be renamed to FreeAdhocUDF. This bug has been fixed in flu.cpp for the next version.
Firebird 2.x does not have any of these problems :-)
In compiling FreeAdhocUDF for MacOSX, it has to be noted that MacOSX has no idea of sysinfo.h, so I had to add a chunk of code to handle the getting of a MAC address, and to get the random_info/randomness for GUIDs. This does seem to work nicely now.
The FreeAdhocUDF libraries I have provided are 32bit intel for Firebird 1.5.5 and Firebird 2.x, if you want to build ppc libraries, or 64bit libraries enjoy. If you have problems, let me know.
On ppc you "might" have to add the following to the Makefile
LDFLAGS=$(CF) $(LIB) -bundle -flat_namespace -undefined suppress to
LDFLAGS=$(CF) $(LIB) -bundle -flat_namespace -undefined suppress /usr/sys/bundle.o