Re: Handlers

[Neal H. Walfield]

I know know why you call this a handler; it seems to me that it is
just a semi-generic list package.  Am I missing something?

You can find a slighly more flexible and generic implementation here:

  
http://cvs.savannah.gnu.org/viewvc/hurd-l4/viengoos/list.h?root=hurd&view=markup

I've been using that for a while and am quite satisfied with it.

Perhaps you'll find it useful.

Neal


Two comments:

At Fri, 29 Aug 2008 14:36:56 +0200,
Marco Gerards wrote:
> +void
> +grub_handler_unregister (grub_handler_t *head, grub_handler_t handler)
> +{
> +  grub_handler_t *p, q;
> +
> +  for (p = head, q = *p; q; p = &(q->next), q = q->next)
                    ^^^^^^                     ^^^^^^^^^^^

This is a bit inconsistent.

  for (p = head, q = *head; q; p = &(q->next), q = q->next)

or

  for (p = head, q = *p; q; p = &(q->next), q = *p)


Or, more succinctly:

  for (p = head; (q = *p); p = &(q->next))


> +int
> +grub_handler_iterate (grub_handler_t head,
> +                   int (*hook) (const grub_handler_t handler))
> +{
> +  grub_handler_t p;
> +
> +  for (p = head; p; p = p->next)
> +    if (hook (p))
> +      break;
> +
> +  return 0;
> +}

A suggestion: when HOOK returns a non-zero value, return that from the
function:

     for (p = head; p; p = p->next)
       {
         int ret = hook (p);
         if (ret)
           return ret;
       }
     return 0;