Hi Ales,
Your sample code should crash because of typeInfo->getTypeName()
returned 0. It is the correct behavior of getTypeName() that's why we
could see NULL-check in DOMDocumentImpl.cpp (but not in your code).
Good luck!
Vitaly
trceka wrote:
Hi all!
I'm porting some application from using xerces-c 2.8.0 to 3.1.1. I have
modified all the code that was using functions/procedures that changed
between version and successfully compiled the application. Things seemed to
work, until I got a crash [SIGILL] in calling the cloneNode(true) [deep
copy]. After poking around, the problem was identified in the call to
typeInfo->getTypeName(), in the DOMDocumentImpl.cpp:1086:
+++
const DOMTypeInfo * typeInfo=((DOMElement*)source)->getSchemaTypeInfo();
// copy it only if it has valid data
if(typeInfo&& typeInfo->getTypeName()!=NULL)
clonedTypeInfo=new (this) DOMTypeInfoImpl(typeInfo->getTypeNamespace(),
typeInfo->getTypeName());</code>
+++
The problem lies in the fact, that getSchemaTypeInfo returns something that
is not null (actually, it returns&DOMTypeInfoImpl::g_DtdValidatedElement),
but the object is corrupted, as soon as you try to access members, you get
SIGILL and coredump.
Here is a small main function created to demonstrate this problem:
+++
int main()
{
xercesc::XMLPlatformUtils::Initialize();
xercesc::DOMImplementation* dom_impl =
xercesc::DOMImplementationRegistry::getDOMImplementation(MakeXMLCh("LS"));
const XMLCh* uri = MakeXMLCh("urn:bla:1.0");
xercesc::DOMDocument* dom_doc = dom_impl->createDocument(uri,
MakeXMLCh("doc"), NULL);
xercesc::DOMElement* el = dom_doc->createElementNS(uri,
MakeXMLCh("elem"));
const xercesc::DOMTypeInfo* typeInfo = el->getSchemaTypeInfo();
if( typeInfo == NULL ) { std::cout<< "null"<< std::endl; }
else
{
char* tmp = xercesc::XMLString::transcode(typeInfo->getTypeName());
std::cout<< tmp<< std::endl;
delete[] tmp;
}
xercesc::XMLPlatformUtils::Terminate();
return 0;
}
+++
Note: MakeXMLCh() is a function that is included from some other code.
The code above is enough to get the crash. After searching up and down the
internet, I am baffled, is this a bug, or am I doing something awfully
wrong?
Platform: AIX 5.3, xlC 9.0
Xerces-c: 3.1.1, AIX binary
Regards,
Ales
