Re: [xml] Still trying to handle entities using the SAX interface

[Daniel Veillard <veillard redhat com>]

On Wed, Apr 18, 2001 at 03:04:00PM +0200, Fabrizio Ammollo wrote:
> I discovered that line 4931 in parser.c is triggering the error :

  error in your viewpoint ....

> ret = xmlParseBalancedChunkMemory(ctxt->myDoc,
>       ctxt->sax, NULL, ctxt->depth,
>       value, &list);
>
> The problem is that the third parameter should be a pointer to my initial 
> user_data, instead it is passed as NULL, so from within the called function 
> the original value is lost, and eventually my characters() callback function 
> is called with the wrong user_data.
>
> I modified the line in this way :
>
> ret = xmlParseBalancedChunkMemory(ctxt->myDoc,
>       ctxt->sax, ctxt->userData, ctxt->depth,
>       value, &list);
>
> My program works as I expected, but I reran the "make check" and I have 
> discovered that MANY tests, mainly those related to entities but also others 
> that contain entities, don't work anymore as they should.

  right, so i won't take this change, someone already suggested it before
and I came to the same conclusion, it breaks all non-SAX parsing.

> For what I have so far understood about how the library works, it is certain 
> that the change I have made impacts also on the normal DOM building behaviour.

  right

> What I think is that ctxt->userData should be passed instead of NULL only if 
> the parsing was initially called from the SAX API functions, but apparently 
> there is nothing which indicates this. :-(
> Before going further, do you think this is the right approach to follow 
> (except using the DOM API) ?

  Well using SAX if you make use of non-trivial entities is hard, I warned you
about this. To put it simply doing all the checkings required for well
formedness and validation in the presence of entities is complex, breaking
all this for the people using only SAX (and hence a minimal subset of libxml)
is not something I'm gonna approve.
  Now if you make a patch wich don't break binary compatibility and don't
break the whole enviroment I will certainely take it.

Daniel

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