Crash in UA_BrowseResponse_clear

[Andreas Geisler]

Hello,

I'm using v1.2-rc2-45-gf4270ceb.

The callstack:

  ucrtbased.dll!00007ffaa2cc1ea0() Unknown

  ucrtbased.dll!00007ffaa2cc54a5() Unknown

  ucrtbased.dll!00007ffaa2cc5bb8() Unknown

  readTree.exe!UA_Array_delete(void * p, unsigned __int64 size, const UA_DataType * type) Line 9179 C

  readTree.exe!String_clear(UA_String * s, const UA_DataType * _) Line 7950 C

  readTree.exe!NodeId_clear(UA_NodeId * p, const UA_DataType * _) Line 8085 C

  readTree.exe!ExpandedNodeId_clear(UA_ExpandedNodeId * p, const UA_DataType * _) Line 8232 C

  readTree.exe!clearStructure(void * p, const UA_DataType * type) Line 9020 C

  readTree.exe!UA_clear(void * p, const UA_DataType * type) Line 9108 C

  readTree.exe!UA_Array_delete(void * p, unsigned __int64 size, const UA_DataType * type) Line 9175 C

  readTree.exe!clearStructure(void * p, const UA_DataType * type) Line 9025 C

  readTree.exe!UA_clear(void * p, const UA_DataType * type) Line 9108 C

  readTree.exe!UA_Array_delete(void * p, unsigned __int64 size, const UA_DataType * type) Line 9175 C

  readTree.exe!clearStructure(void * p, const UA_DataType * type) Line 9025 C

  readTree.exe!UA_clear(void * p, const UA_DataType * type) Line 9108 C

  readTree.exe!UA_BrowseResponse_clear(UA_BrowseResponse * p) Line 23230 C++

> readTree.exe!collectNodeIds(std::vector<std::pair<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,UA_NodeId>,std::allocator<std::pair<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,UA_NodeId> > > & nodeIds, UA_NodeId fromNodeId, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & prefixForOutput) Line 182 C++

  readTree.exe!collectNodeIds(std::vector<std::pair<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,UA_NodeId>,std::allocator<std::pair<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,UA_NodeId> > > & nodeIds, UA_NodeId fromNodeId, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & prefixForOutput) Line 177 C++

  readTree.exe!main(int argc, char * * argv) Line 281 C++

  [External Code]

Source code of my user function (which is supposed to recursively collect NodeIds of all child nodes of a given node, so that they can later be used in a read request):

void collectNodeIds(vector<pair<string, UA_NodeId>>& nodeIds,

                    UA_NodeId fromNodeId,

                    const string& prefixForOutput)

{

  UA_BrowseRequest bReq;

  UA_BrowseRequest_init(&bReq);

  bReq.requestedMaxReferencesPerNode = 0;

  bReq.nodesToBrowse = UA_BrowseDescription_new();

  bReq.nodesToBrowseSize = 1;

  bReq.nodesToBrowse[0].nodeId = fromNodeId;

  bReq.nodesToBrowse[0].resultMask = UA_BROWSERESULTMASK_ALL; /* return everything */

  auto bResp = UA_Client_Service_browse(g_client, bReq);

  for (size_t i = 0; i < bResp.resultsSize; ++i)

  {

    for (size_t j = 0; j < bResp.results[i].referencesSize; ++j)

    {

      auto* ref = &(bResp.results[i].references[j]);

      if (ref->referenceTypeId.identifier.numeric == UA_NS0ID_HASCOMPONENT

          || ref->referenceTypeId.identifier.numeric == UA_NS0ID_ORGANIZES)

      {

        auto browseName = string(reinterpret_cast<char*>(ref->browseName.name.data), ref->browseName.name.length);

        auto name = prefixForOutput + "." + browseName;

        if (ref->typeDefinition.nodeId.identifierType == UA_NODEIDTYPE_NUMERIC

          && ref->typeDefinition.nodeId.identifier.numeric == UA_NS0ID_BASEDATAVARIABLETYPE)

          nodeIds.emplace_back(make_pair(name, ref->nodeId.nodeId));

        else

          collectNodeIds(nodeIds, ref->nodeId.nodeId, name); // Recursion

      }

    }

  }

  UA_BrowseResponse_clear(&bResp);

  UA_BrowseRequest_clear(&bReq);

}

What else could be helpful to find the cause?

Or did I misunderstand how to use the *_clear functions?

If I don't call UA_BrowseResponse_clear, Visual Leak Detector reports numerous memory leaks.

Regards

A. Geisler

[Andreas Geisler]

Seems that I missed to apply UA_NodeId_copy. 

What are the rules for memory management in open62541, i.e. when to use *_copy, *_clear etc.? Is this documented somewhere?

A. Geisler

[Julius Pfrommer]

Have a look here:

https://open62541.org/doc/current/types.html#generic-type-handling

https://open62541.org/doc/current/tutorial_datatypes.html

Regards