Re: [xml] list deallocator problem

[Gary Pennington <Gary Pennington sun com>]

Aleksey Sanin wrote:

> Hi, All!
>
> I am trying to use xmlList declared in list.h and I found a small
> problem with it. The xmlListDeallocator is declared in list.h as follows:
>     typedef void (*xmlListDeallocator) (xmlLinkPtr lk);
> i.e. it expects a pointer to xmlLink structure. However, the xmlLink 
> structure
> itself is declared inside list.c and by this it is not accessible to 
> the custom
> list data deallocator. I would suggest to do following changes:
>
>     1) change the declaration of xmlListDeallocator in list.h to
>
>     typedef void (*xmlListDeallocator) (void *data);
>
>     2) change the implementation of xmlLinkDeallocator() in link.c
>     from
>
>     /**
>      * xmlLinkDeallocator:
>      * @l:  a list
>      * @lk:  a link
>      *
>      * Unlink and deallocate @lk from list @l
>      */
>     static void
>     xmlLinkDeallocator(xmlListPtr l, xmlLinkPtr lk)
>     {
>         (lk->prev)->next = lk->next;
>         (lk->next)->prev = lk->prev;
>         if(l->linkDeallocator)
>             l->linkDeallocator(lk);
>         xmlFree(lk);
>     }
>
>     to
>
>     /**
>      * xmlLinkDeallocator:
>      * @l:  a list
>      * @lk:  a link
>      *
>      * Unlink and deallocate @lk from list @l
>      */
>     static void
>     xmlLinkDeallocator(xmlListPtr l, xmlLinkPtr lk)
>     {
>         (lk->prev)->next = lk->next;
>         (lk->next)->prev = lk->prev;
>         if(l->linkDeallocator && lk->data)
>             l->linkDeallocator(lk->data);
>         xmlFree(lk);
>     }
>
>
> Aleksey.
Hi,

What's the problem? You can use xmlLinkGetData() to get at the data held 
by the link and that's all you should need access to. I don't think any 
changes are required.

e.g.

In your deallocator
{
...
void * data = xmlLinkGetData(lk);
<do whatever you want with data, probably just free it>
}

Gary

--
Gary Pennington
Solaris Kernel Development,
Sun Microsystems
Gary Pennington sun com