Re: [xml] how to clean up properly after SAX parsing

[Daniel Veillard <veillard redhat com>]

On Tue, Jul 10, 2007 at 12:00:11PM +0100, Geoff Richards wrote:
> Hi,
>
> I'm just figuring out how to do some simple SAX parsing with libxml
> (version 2.6.29, Debian unstable).  I haven't tried using this from C
> before, so I'm probably making simple mistakes.
>
> Valgrind is telling me I've got a leak.  Am I missing some sort of
> memory clean-up call?
>
> This is roughly what I've got (some of the handlers are NULL, the ones
> I do have just print some debugging info for now):
>
>     f = fopen(filename, "rb"); 
>     ret = fread(chars, 1, 4, f);
>     ctxt = xmlCreatePushParserCtxt(&sax_handlers, 0, chars, ret, filename);
>
>     while ((ret = fread(chars, 1, 3, f)) > 0)
>         xmlParseChunk(ctxt, chars, ret, 0);
>     ret = xmlParseChunk(ctxt, chars, 0, 1);
>
>     xmlFreeParserCtxt(ctxt);
>     if (ret != 0)
>         fprintf(stderr, "xmlSAXUserParseFile returned error %d\n", ret);
>     fclose(f);
>
> The blocks of memory which are being leaked were allocated by
> xmlCreatePushParserCtxt().
>
> Any ideas?

  1/ read the docs
     http://xmlsoft.org/xmlmem.html
  2/ use testSAX.c from the distribution as example
     valgrind --leak-check=full testSAX --push test/isolat3
     works just fine for me
  3/ do NOT use SAX unless you REALLY need it, use the reader or
     the tree API.

Daniel

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