Sorry, I made some misunderstanding.
The libxml source that I looked at was somewhat old,
and the latest source says that _priavte is for application data.
So, using _private to store VALUE is valid way.
But, the set-to-null problem is still there... :-(
07/11/29 に keisuke fukuda<[EMAIL PROTECTED]> さんは書きました:
> Hi,
>
> I've been trying this problem these days.
> For now I've not yet reached to an answer, but this may be a hint :
>
> gdb told me that the problem is about memory allocation,
> especially a double-freeing problem.
>
> Changing optyk's script like this :
>
> div2.each do |child|
> #c = child.clone
> c = child.copy(false)
> div1.child_add(c)
> exit # <--------- add this
> end
>
> causes
>
> *** glibc detected *** ruby: double free or corruption (fasttop): 0x088b5db0
> ***
> ======= Backtrace: =========
> /lib/libc.so.6[0x4f2c0f5d]
> /lib/libc.so.6(cfree+0x90)[0x4f2c45b0]
> /usr/lib/libxml2.so.2(xmlFreeNode+0x14b)[0x4fa1ce8b]
> ./xml/libxml_so.so(ruby_xml_node2_free+0x5f)[0x4865ef]
> /usr/lib/libruby.so.1.8(rb_gc_call_finalizer_at_exit+0xa7)[0x457f4a87]
> /usr/lib/libruby.so.1.8[0x457dad07]
> /usr/lib/libruby.so.1.8(ruby_cleanup+0xf9)[0x457e2ad9]
> /usr/lib/libruby.so.1.8(ruby_stop+0x1d)[0x457e2bbd]
> /usr/lib/libruby.so.1.8[0x457edae1]
> ruby[0x80485f2]
> /lib/libc.so.6(__libc_start_main+0xdc)[0x4f270dec]
> ruby[0x8048521]
>
>
> Next, I found 'double-wrapping' in ruby_xml_node2_wrap().
> It happened because xmlNode's member "_private" was set to NULL by
> xmlAddChild() function.
> '_private' is used to store the xmlNode object's wrapper VALUE object
> (which is actually a Ruby object pointer).
>
> you can see it by inserting following code in ruby_xml_node_child_set_aux()
>
> fprintf(stderr, "--- %p\n", chld->_private);
> ret = xmlAddChild(pnode->node, chld);
> fprintf(stderr, "--- %p\n", chld->_private);
>
> ==> (Run optyk's script)
> --- 0xb7f8b9b8
> --- (nil)
>
> Just restoring '_private' value didn't fix the problem, but there may
> be 'set-to-null problem'
> elsewhere.
> So, to conclude, I'm afraid it's not a good idea to store VALUE
> pointer in '_private'.
> libxml header file says its for internal use related to CORBA ... :-(
>
> I'm glad if this could be a help for you, experts :-)
>
> 2007/11/27, optyk <[EMAIL PROTECTED]>:
> > hello,
> >
> > I get segmentation fault when add the cloned/copied node to other
> > node,
> > script to problem reproduction below,
> >
> > segv appears when use clone and copy methods,
> > what's interesting, with clone segv is thrown in div1.child_add(c)
> > line (see script)
> > but when use copy I get it in printf root statement, moreover copy
> > seems to work wrong only for text nodes, when use 't3' div everything
> > works fine
> >
> > I get this error on 0.5.2.0, 0.5.2.1 and 0.5.2.2 (latest svn) version
> >
> > it looks like fix is required in ruby-libxml code,
> >
> > BTW. it looks also like ruby_xml_node_copy() in ruby_xml_node.c calls
> > xmlCopyNode() with wrong attributes, it should be 2 for shallow copy
> > and 1 for deep copy
> >
> > regards,
> > Piotrek
> >
> > -------------------- SCRIPT ---------------------
> > require 'xml/libxml'
> >
> > str = <<-STR
> > <html>
> > <body>
> > <div class="textarea" id="t1"
> > style="STATIC">werwerwerwerwer </div>
> > <div class="textarea" id="t2" style="STATIC">
> > Quisque et diam dapibus nisi bibendum blandit.
> > </div>
> > <div class="textarea" id="t3" style="STATIC">
> > <p>aaaaaaaaa</p>
> > </div>
> > </body>
> > </html>
> > STR
> >
> >
> > XML::Parser.default_keep_blanks = false
> > xp = XML::Parser.new
> > xp.string = str
> > doc = xp.parse
> >
> > xpath = "//[EMAIL PROTECTED]'t1']"
> > div1 = doc.find(xpath).to_a[0]
> > printf "xxx div1: #{div1}\n"
> >
> > xpath = "//[EMAIL PROTECTED]'t2']"
> > div2 = doc.find(xpath).to_a[0]
> > printf "xxx div2: #{div2}\n"
> >
> >
> > div2.each do |child|
> > #c = child.clone
> > c = child.copy(false)
> > div1.child_add(c)
> > end
> >
> > printf "xxx root: #{doc.root}\n"
> >
> >
> > _______________________________________________
> > libxml-devel mailing list
> > [email protected]
> > http://rubyforge.org/mailman/listinfo/libxml-devel
> >
>
>
> --
> FUKUDA, Keisuke <福田圭祐>
> http://d.hatena.ne.jp/keisukefukuda/
>
--
FUKUDA, Keisuke <福田圭祐>
http://d.hatena.ne.jp/keisukefukuda/
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