Re: [xml] xmlCopyDtd() does not copy the children of the DTD node...

[Daniel Veillard <veillard redhat com>]

On Wed, Jan 23, 2002 at 04:39:25PM +0000, Anthony Jones wrote:
> If we call xmlCopyDoc() on a document that contains declarations etc 
> within its DTD, they will not be copied. This can be demonstrated by
> running the attached program on, for instance, test/defattr.xml, and
> diffing original.xml and final.xml.
>
> This is because xmlCopyDtd() does not copy the children of the DTD node -
> is this the correct behaviour?

   It used to be the correct behaviour but is not anymore and
results in the problem you're seing. DTD declarations used not to show up
as children of the DTD node. they do now (to be able to keep ordering,
and insert comments, PIs, etc...).

> If not, I'll happily write a patch to try
> and fix it, but I'm not entirely sure about the correct way to do it:
>
> 1) Should xmlCopyDtd() recursively copy the children of the DTD node, or do
>    we want to keep the current behaviour, and have a different function to
>    copy a DTD node and its children?

     it should provide copies. Note that these copies are created in the 
     generated dtd as part of ret->entities ret->notations ret->elements 
     and ret->attributes, the problem is that these nodes should also show
     up as children of the dtd node. Without preserving ordering it's
     a simple matter of walking the hash tables an inserting in theclarations.
     If one want to preserve the ordering of the DTD children this becomes
     more complex,

> 2) This would require the facility to copy the element/attribute/entity
>    declaration nodes (any others?), should this just be added to
>    xmlStaticCopyNode()?

      Hum, the facility exist but is relatively different from "normal"
      nodes copy, so I'm tempted to keep them distinct so far.

  I would appreciate if you could work on this, I have little use myself
to get this right and this may need a bit of debugging. Morover getting more
people to lean libxml2 internals can only be a good thing :-)

  thanks in advance !

Daniel

-- 
Daniel Veillard      | Red Hat Network https://rhn.redhat.com/
veillard redhat com  | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
http://veillard.com/ | Rpmfind RPM search engine http://rpmfind.net/