in reply to Re^2: XML::LibXML memory leak
in thread XML::LibXML memory leak

There's no reason to go messing with someone else's namespace. 

sub detach {
    my( $node ) = @_;
    $node->parentNode->removeChild( $node );
}

detach($node);

[download]

would work just as well.

Except it's not enough. It won't separate it from the document. 

$ perl -MXML::LibXML -E'
   my $node;
   {
      my $xml = "<root><foo><bar/></foo></root>";
      my $doc = XML::LibXML->new->parse_string($xml);
      ($node) = $doc->findnodes("//bar");
      $node->parentNode->removeChild($node);
   }
   {
      my $doc = $node->ownerDocument;
      say "owner=", $doc;
      if ($doc) { say $_->nodeName for $doc->findnodes("//*"); }
   }
'
owner=XML::LibXML::Document=SCALAR(0x817bcb8)
root
foo

[download]

You need to give the node a new document. 

$ perl -MXML::LibXML -E'
   my $foster_home = XML::LibXML::Document->new("1.0", "UTF-8");
   my $node;
   {
      my $xml = "<root><foo><bar/></foo></root>";
      my $doc = XML::LibXML->new->parse_string($xml);
      ($node) = $doc->findnodes("//bar");
      $node->setOwnerDocument($foster_home);
   }
   {
      my $doc = $node->ownerDocument;
      say "owner=", $doc;
      if ($doc) { say $_->nodeName for $doc->findnodes("//*"); }
   }
'
owner=XML::LibXML::Document=SCALAR(0x832af38)

[download]

Note that transfers the node's children too.

Replies are listed 'Best First'.
Re^4: XML::LibXML memory leak
by spstansbury (Monk) on Dec 08, 2010 at 17:38 UTC

    Thank you. Very much...

    I get it, but - but would like to clarify. I give the node to a new document outside my loop, like this:

    my $foster_home = XML::LibXML::Document->new("1.0", "UTF-8");

# Register the namespaces:
$cve_xc->registerNs( def => 'http://scap.nist.gov/schema/feed/vulnerab
+ility/2.0' );
$cve_xc->registerNs( vuln => 'http://scap.nist.gov/schema/vulnerabilit
+y/0.4' );
$cve_xc->registerNs( cvss => 'http://scap.nist.gov/schema/cvss-v2/0.2'
+ );

# Find the appropriate CVE entry in the data source:
for my $entry ( $cve_xc->findnodes( "/def:nvd/def:entry[\@id = '$cve_i
+d']" )) {
    if ( my ( $metrics ) = $cve_xc->findnodes( 'vuln:cvss/cvss:base_me
+trics', $entry )) {
    
        ($av) = $cve_xc->find('cvss:access-vector', $metrics);
        ($ac) = $cve_xc->find('cvss:access-complexity', $metrics);
        ($au) = $cve_xc->find('cvss:authentication', $metrics);
        ($ci) = $cve_xc->find('cvss:confidentiality-impact', $metrics)
+;
        ($ii) = $cve_xc->find('cvss:integrity-impact', $metrics);
        ($ai) = $cve_xc->find('cvss:availability-impact', $metrics);
        
    }
    else {
        $av = "";
        $ac = "";
        $au = "";
        $ci = "";
        $ii = "";
        $ai = "";
    }
}
$av->setOwnerDocument($foster_home);
$ac->setOwnerDocument($foster_home);
$au->setOwnerDocument($foster_home);
$ci->setOwnerDocument($foster_home);
$ii->setOwnerDocument($foster_home);
$ai->setOwnerDocument($foster_home);

    [download]

    But I'm a little confused as where to go from here: my $doc = $node->ownerDocument;

    I'm also stymied at the moment as I'm getting "Can't locate object method "setOwnerDocument" via package "XML::LibXML::NodeList" at..."

    I've reinstalled XML::LIbXML via CPAN, have "Node.pod" in /Library/Perl/5.10.0/darwin-thread-multi-2level/XML/LibXML, but only NodeList.pm...

[reply]
[d/l]
[select]

      But I'm a little confused as where to go from here: my $doc = $node->ownerDocument;

         {
      my $doc = $node->ownerDocument;
      say "owner=", $doc;
      if ($doc) { say $_->nodeName for $doc->findnodes("//*"); }
   }

      [download]

      was just to demonstrate the issue. It shouldn't be part of your code.

      I'm also stymied at the moment as I'm getting "Can't locate object method "setOwnerDocument" via package "XML::LibXML::NodeList" at..."

      Nodes have owner documents, not result sets. Change the owner of the nodes in the result set.

      Can't you just extract the data you need from the nodes instead of keeping the nodes themselves?

[reply]
[d/l]

        Yes, absolutely! All I need is the data...

        That's what I thought that I was doing with:

        $av = $cve_xc->find('cvss:access-vector', $metrics);

        [download]
[reply]
[d/l]

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