[Libvirt-cim] [PATCH] Add association results filtering

[Dan Smith]

KR> This adds result filtering so that an association only returns
KR> instances that match the result class specified during the
KR> query. Such an example is the following:

I think this is a good idea.  It allows our association handlers to
ignore the result class (if so desired) knowing that std_association
will do the result class filtering before returning to the client.
Handlers could also look at the result_class field in std_assoc_info
to optimize if desired or necessary.

KR> +        inst_list_init(&result_list);
KR> +
KR> +        for (i = 0; list->list[i] != NULL; i++) {
KR> +                op = CMGetObjectPath(list->list[i], &s);
KR> +                if ((s.rc != CMPI_RC_OK) || CMIsNullObject(op))
KR> +                          goto out;
KR> +
KR> +                s = CMSetNameSpace(op, ns);
KR> +                if (s.rc != CMPI_RC_OK)
KR> +                          goto out;
KR> +
KR> +                if (!match_op(broker, op, filter_class))
KR> +                          continue;
KR> +
KR> +                inst_list_add(&result_list, list->list[i]);
KR> +                c++;
KR> +        }
KR> +
KR> +        inst_list_free(list);
KR> +        if (list->list != NULL) {
KR> +                CU_DEBUG("\tinst_list_free failed.\n");
KR> +                goto out;
KR> +        }
KR> +
KR> +        inst_list_init(list);
KR> +
KR> +        for (i = 0; i <= c; i++)
KR> +                inst_list_add(list, result_list.list[i]);

Instead of filling another list, and then copying it back, why not
just make a copy of the incoming list and then copy matching instances
back to the original?  Something like this:

  struct inst_list tmp_list;

  tmp_list = *list;
  inst_list_init(list);

  for (items in tmp_list) {
    if (item is resultclass)
      inst_list_add(list, item);
  }

  inst_list_free(tmp_list);

That should work, and only copy the needed instance pointers once,
instead of running through the list twice.

-- 
Dan Smith
IBM Linux Technology Center
Open Hypervisor Team
email: danms at us.ibm.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 188 bytes
Desc: not available
URL: <http://listman.redhat.com/archives/libvirt-cim/attachments/20071107/f9da1d72/attachment.sig>