0026961: Recover possibility to read files in old persistence format

[occt.git] / src / StdLPersistent / StdLPersistent_Data.cxx

diff --git a/src/StdLPersistent/StdLPersistent_Data.cxx b/src/StdLPersistent/StdLPersistent_Data.cxx
new file mode 100644 (file)
index 0000000..c36bb49
--- /dev/null
+++ b/src/StdLPersistent/StdLPersistent_Data.cxx
@@ -0,0 +1,106 @@
+// Copyright (c) 2015 OPEN CASCADE SAS
+//
+// This file is part of Open CASCADE Technology software library.
+//
+// This library is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License version 2.1 as published
+// by the Free Software Foundation, with special exception defined in the file
+// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
+// distribution for complete text of the license and disclaimer of any warranty.
+//
+// Alternatively, this file may be used under the terms of Open CASCADE
+// commercial license or contractual agreement.
+
+#include <StdLPersistent_Data.hxx>
+#include <StdObjMgt_ReadData.hxx>
+
+#include <TDF_Data.hxx>
+#include <TDF_Attribute.hxx>
+
+
+//! Create a transient label tree from persistent data
+class StdLPersistent_Data::Parser
+{
+public:
+  //! Start parsing a persistent data.
+  Parser (const TColStd_HArray1OfInteger&    theLabels,
+          const StdLPersistent_HArray1OfPersistent& theAttributes)
+    : myLabelsIter (theLabels)
+    , myAttribIter (theAttributes) {}
+
+  //! Fill a transient label with data.
+  void FillLabel (TDF_Label theLabel)
+  {
+    Standard_Integer i;
+
+    // Read attributes count
+    myLabelsIter.Next();
+    Standard_Integer anAttribCount = myLabelsIter.Value();
+
+    // Add attributes to the label
+    for (i = 0; i < anAttribCount; i++)
+    {
+      // read persistent attribute
+      Handle(StdObjMgt_Persistent)& aPAttrib = myAttribIter.ChangeValue();
+      myAttribIter.Next();
+
+      // create transient attribute and add it to the label
+      if (aPAttrib)
+        theLabel.AddAttribute (aPAttrib->CreateAttribute());
+    }
+
+    // Read child labels count
+    myLabelsIter.Next();
+    Standard_Integer aSubLabelsCount = myLabelsIter.Value();
+
+    // Create child labels
+    for (i = 0; i < aSubLabelsCount; i++)
+    {
+      // read tag of child label
+      myLabelsIter.Next();
+      Standard_Integer aSubLabelTag = myLabelsIter.Value();
+
+      // create and fill child label
+      TDF_Label aSubLabel = theLabel.FindChild (aSubLabelTag, Standard_True);
+      FillLabel (aSubLabel);
+    }
+  }
+
+private:
+  TColStd_HArray1OfInteger   ::Iterator myLabelsIter;
+  StdLPersistent_HArray1OfPersistent::Iterator myAttribIter;
+};
+
+//=======================================================================
+//function : Read
+//purpose  : Read persistent data from a file
+//=======================================================================
+void StdLPersistent_Data::Read (StdObjMgt_ReadData& theReadData)
+{
+  theReadData >> myVersion >> myLabels >> myAttributes;
+}
+
+//=======================================================================
+//function : Import
+//purpose  : Import transient data from the persistent data
+//=======================================================================
+Handle(TDF_Data) StdLPersistent_Data::Import() const
+{
+  if (myLabels.IsNull() || myAttributes.IsNull())
+    return NULL;
+
+  // Create tree of labels and add empty transient attributes to them
+  Handle(TDF_Data) aData = new TDF_Data;
+  Parser (*myLabels->Array(), *myAttributes->Array()).FillLabel (aData->Root());
+
+  // Import transient attribuites from persistent data
+  StdLPersistent_HArray1OfPersistent::Iterator anAttribIter (*myAttributes->Array());
+  for (; anAttribIter.More(); anAttribIter.Next())
+  {
+    Handle(StdObjMgt_Persistent)& aPAttrib = anAttribIter.ChangeValue();
+    if (aPAttrib)
+      aPAttrib->ImportAttribute();
+  }
+
+  return aData;
+}