Plugin project proposal

[Simo Sorce]

On Thu, 15 Jul 2010 14:25:25 -0400
Zhanna Tsitkova <tsitkova at MIT.EDU> wrote:

> 
> On Jul 15, 2010, at 1:14 PM, Russ Allbery wrote:
> 
> >>
> >> 2.  2. It was suggested to use hash tables for the plugin  
> >> interfaces in
> >> lieu of C structures. This would provide better plugin impl.
> >> version control and interface extensibility.
> >
> > I'm not sure what you mean by hash tables here.
> 
> Suppose we have defined an interface for plugin_A.
> At later time one may want to extend  the interface of this plugin.
> Now, can these two versions coexist? Yes, and one of the possible  
> solutions is to implement v-tables as hashes.
> In this case the interface consumer can check for the availability
> of the new method by querying  the hash-table. If "new method" is
> not implemented, it returns null pointer. And one can decide how to  
> proceed further.

if (vtable->new_method == NULL) { /* not implemented */

Simo.

-- 
Simo Sorce * Red Hat, Inc * New York