Step thread safety improvement

[dpasukhi]

Category

Data Exchange

Severity

Major

Description

Original issue: https://dev.opencascade.org/content/stepcontrolreader-access-violation-reading-location
https://tracker.dev.opencascade.org/view.php?id=33657
The issue about be able to read and write the STP using different threads.
Needs to be sure that STP reading and writing is a thread safety.
The assumption: the XCAF document (out) is a isolated.

Expected Behavior

Reading and Writing in different threads are stable

Actual Behavior

Crash during calling Reading or Writing in multiple threads

Sample Code or DRAW Tcl Script

// test 1
  STEPCAFControl_Controller::Init();
  OSD_Parallel::For(0, 1000, [](int) {
    STEPCAFControl_Reader aReader;
    aReader.SetColorMode(true);
    STEPCAFControl_Writer aWriter;
    aWriter.SetDimTolMode(true);
  });

  // test 2
  STEPCAFControl_Controller::Init();
  OSD_Parallel::For(0, 1000, [&](int){
   STEPControl_Reader aReader;
   aReader.ReadFile(theArgV[1], DESTEP_Parameters{});
   aReader.TransferRoots();
  });

  // test 3
  std::atomic_int anInd = 0;
  STEPCAFControl_Controller::Init();
  TopoDS_Shape aShape = DBRep::Get(theArgV[1]);
  OSD_Parallel::For(0, 1000, [&](int){
   STEPControl_Writer aWriter;
  aWriter.Transfer(aShape,STEPControl_StepModelType::STEPControl_AsIs, DESTEP_Parameters{});
  TCollection_AsciiString aNewFileName = theArgV[2];
  aNewFileName += anInd;
  aNewFileName += ".stp";
  aWriter.WriteStream(...);
  });