[Vala] Adding macros to a vapi for a non-gobject type library

[Geoff Johnson <geoff jay gmail com>]

First off, I've never written a vapi file before so excuse my lack of
understanding. I've started to write a vapi file for the comedi library
which contains several macros for channel setup, for example:

#define CR_PACK(chan,rng,aref) ( (((aref)&0x3)<<24) | (((rng)&0xff)<<16) |
(chan) )

My question is how are macros represented in a vapi file? Or, is there some
documentation on writing vapi files for non-gobject type libraries? I've
done a fair amount of searching and found some good examples but there's
nothing comprehensive.

Thanks