Adding new filters

The procedures for adding parameters and regression tests are the same for filters as for queuing disciplines.

For the filter, a file called f_name.c needs to be written, that provides the functions and data structures that define how the filter is processed. Furthermore, the following files need to be changed:

Makefile

include f_name.c in FILES

tcc/Makefile

include f_name.o in OBJS

tcc/filter.h

add a declaration of the descriptor

tcc/tcng.l

parses the filter name and returns a suitable token

tcc/tcng.y

declares the token (in a %token line), and processes the filter in the filter_name rule