RE: Crash in DOM_Document::createElement() when name an empty string

[Piras Sandro (KSDB 121)]

Hi Dave,
yes, it compiles.. at least the Sun compiler version 5.3 I'm actually
using.

I copied the code from our project in a single sourcefile and without
all the object oriented stuff only to see how it works. Like in the
project, calling DOM_Document::createElement("") generates a core file,
the same when calling DOM_Document::createElement(name) when name
contains an empty string, it doesn't throw an exception.. I tried
filling name with a space -> name = " ", then createElement() throws an
exception.

See the function createNameValue(), the function createNameValue() will
be callend in main() in a try block. 

Regards
Sandro

Code:

#include <iostream>

#include <xercesc/dom/deprecated/DOM.hpp>


using namespace XERCES_CPP_NAMESPACE;


using std::cout;
using std::endl;


DOM_Document myDocument;


DOM_Node makeChild(const char* childName, DOM_Node parentNode, bool
bAllowDuplicate)
//**********************************************************************
************
{
   // Create child node if it does not exist, returns existing one
otherwise

   DOM_Node child = parentNode;
   if (!parentNode.isNull() && (strlen(childName) > 0))
   {
      child = parentNode.getFirstChild();
      while (!child.isNull() &&
!child.getNodeName().equals(DOMString(childName)) &&
             !bAllowDuplicate)
      {
         child = child.getNextSibling();
      } // end while

      if (child.isNull() || bAllowDuplicate)
      {
         child = myDocument.createElement(childName);
         parentNode.appendChild(child);
      } // end if (child.isNull() -> TRUE || (bAllowDuplicate -> TRUE)
   } // end if

   return child;
} // end makeChild()


DOM_Node makePath(const char* path, DOM_Node parentNode)
//******************************************************
{
   char* copyOfPath = new char[strlen(path) + 1];
   copyOfPath[strlen(path)] = '\0';

   strncpy(copyOfPath, path, strlen(path));

   char* pStart = (char*)copyOfPath;
   char* pEnd = pStart;

   bool bContinue = pEnd && *pEnd;
   while (bContinue)
   {
      if ((*pEnd == '/') || (*pEnd == '\0')) // Found the limiter
      {
         if ((*pEnd == '\0')) bContinue = false;
         *pEnd = '\0';

         // Create child node if it does not exist, returns existing one
otherwise
         parentNode = makeChild(pStart, parentNode, false);

         pStart = pEnd + 1;
      } // end if (*pEnd -> '/') OR (*pEnd -> '\0')

      pEnd++;
   } // end while (bContinue -> TRUE)

   return parentNode;
} // end makePath()


DOM_Node makePath(const char* path)
//*********************************
{
   DOM_Node nodeRet;

   if (myDocument.isNull()) myDocument = DOM_Document::createDocument();

   nodeRet = myDocument;

   nodeRet = makePath(path, nodeRet);

   return nodeRet;
} // end makePath()


void createNameValue(const char* name, const char* value, DOM_Node
parent)
//**********************************************************************
**
{
   if (!parent.isNull() && (name != NULL) && (value != NULL))
   {
      cout << "CreateNameValue() : " << "name = \"" << name << "\",
value = \"" << value << "\"" << endl;

      // Crashes when name is an empty string instead to throw an
exception
      //DOM_Element element = myDocument.createElement(name);
      // XXX check whats wrong
      DOM_Element element;
      if (strcmp(name, "") == 0)
      {
         cout << "createNameValue() : call createElement with empty
string" << endl;
         element = myDocument.createElement("");

         //cout << "createNameValue() : call createElement with one
space" << endl;
         //element = myDocument.createElement(" ");

         cout << "createNameValue() : createElement() was successfull"
<< endl;
      }
      else
      {
         cout << "createNameValue() : call createElement with name = \""
<< name << "\"" << endl;
         element = myDocument.createElement(name);
      }
      // XXX

      DOM_Text text = myDocument.createTextNode(value);
      element.appendChild(text);
      parent.appendChild(element);
   } // end if (parent.isNull() -> FALSE) AND (name <> NULL) AND (value
<> NULL)
} // end createNameValue()


int main()
{
   cout << "start" << endl;

   XMLPlatformUtils::Initialize();

   DOM_Node nodeProd = makePath("CMF/Trade/Product");

   const char* name = "";
   const char* value = "";

   cout << "name = \"" << name << "\"" << endl;
   cout << "value = \"" << value << "\"" << endl;

   try
   {
      createNameValue(name, value, makePath("Identifiers", nodeProd));
   }
   catch(...)
   {
     cout << "Exception caught in createNameValue()" << endl;
   }

} // end main()

-----Original Message-----
From: David Bertoni [mailto:[EMAIL PROTECTED] 
Sent: Donnerstag, 29. Mai 2008 19:22
To: c-users@xerces.apache.org
Subject: Re: Crash in DOM_Document::createElement() when name an empty
string

Piras Sandro (KSDB 121) wrote:
> Hi all
> thx for your help.
> 
> I tested also when filling directly an empty string with
> DOM_Document::createElement("") -> crashes
How does this even compile?  "" is not a pointer to a UTF-16 string. 
Can you please provide a small, isolated program that reproduces the
crash?

Dave