Re: [xml] xmlCleanupParser() question / patch

[Daniel Veillard <veillard redhat com>]

On Tue, Jan 19, 2010 at 03:40:30PM +0100, Martin B. wrote:
> Daniel Veillard wrote:
> > On Thu, Jan 14, 2010 at 02:59:50AM +0100, Aron Szabo wrote:
> > > Hi!
> > >
> > > If I use the library in a threaded program and call
> > > xmlCleanupParser() I can't reinitialize it.
> > >
> > > So here's what happens:
> > >
> > > 1. xmlCleanupThreads() is called from xmlCleanupParser()
> > > 2. the global key is deleted by xmlCleanupParser() which was created
> > > by xmlOnceInit()
> > > ...
> >
> >  That makes sense. there is a big problem anyway with
> > xmlCleanupParser() most people seems to think it need to be used after
> > parsing while it's a library global operation and really should not
> > be called after parsing but only when the library is not in use anymore.
> >
> > So overall I'm tempted to change xmlCleanupParser() to become an empty
> > routine, and rename the real function as xmlCleanupLibrary().
> > That way the various shared libraries deployed with that bug won't need
> > to be changed specifically, avoiding crashes when multiple libraries
> > using libxml2 are used. Then your patch should be applied to the new
> > xmlCleanupLibrary() function.
> >
> >  Opinions ?
>
> Makes sense. Though all people that use it correctly will have to
> update their sources, which kind of seems unfair :-)

  Agreed, but the balance of damages is not the same, on one hand you
have a minimal one-time fixed size small leak, and on the other side
you get an ugly crash usually hard to debug because it becomes an
async error when using the library later.

> Best thing would be if xmlCleanupParser() would be removed completely, no?

  That is impossible, for ABI compatibility,

Daniel

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