Re: [gdome]future memory management plans? (was: News(2) on CVS preparing 0.7.0)

[Paolo Casarini <casarini CS UniBO IT>]

On Fri, 9 Nov 2001, Tobias Peters wrote:

> On Fri, 9 Nov 2001, Paolo Casarini wrote:
> > I think I can resolve the problem you have focused in the next week-end. I
> > think I can resolve it without adding any other memory structure only
> > using reference counting and information holded by the libxml2 xmlNode
> > structure.
> 
> Well, if you can solve that, it would be great. Maybe I overlooked
> something. (I have now clue how you want to access detached subtrees, and 
> look forward to see your idea.) 
> 
The idea is to use the Gdome_xml_Node.refcnt, the xmlNode.parent and the
xmlNode._private fields to understand if a Node and the subtree under
it is to be freed on unref.

The n->parent field of a root node of a detached subtree is NULL, so when
the user call unref on such node and its refcnt reach 0 we can free its
xmlNode structure.
  
We need n->_private to know which node of the subtree are to be freed:

Example: suppose to have the follow detached subtree where the node A and
C are referenced each by one GdomeNode*.

<A>        //referenced
  <B>
    <C>    //referenced
      <D/>
    </C>
  </B>
  <E/>
</A>

When the user call unref on A we can free A, B and E libxml2 underling
structures while C and D are taken live by the C reference. When the user
call unref also on C, we can also free C and D underling libxml2
structures.

Bye,
   paolo.
--
Paolo Casarini - casarini cs unibo it