0026229: Add the possibility in OCAF to open/save a document from/to a stream object

TDocStd_Application class extended to open/save a document of XmlOcaf and BinOcaf format
from/to standard SEEKABLE stream object which should support SEEK functionality.

Open and SaveAs DRAW commands got new additional argument "-stream" to turn on using of stream functionality.

The main changes for BinOcaf format applied in:
FSD_BinaryFile class (static method using standard stream added)
BinLDrivers_DocumentRetrievalDriver and BinLDrivers_DocumentStorageDriver classes use standard stream object as an argument

The main changes for XmlOcaf format applied in:
LDOMParser and LDOM_XmlWriter classes  use standard stream object as an argument

Unused class FSD_Archive and its siblings removed from MFC samples.

src/PCDM/PCDM.cxx

@@ -103,3 +103,48 @@ PCDM_TypeOfFileDriver PCDM::FileDriverType(const TCollection_AsciiString& aFileN
     return PCDM_TOFD_Unknown;
   }
 }
+
+//=======================================================================
+//function : FileDriverType
+//purpose  : 
+//=======================================================================
+
+PCDM_TypeOfFileDriver PCDM::FileDriverType (Standard_IStream& theIStream, PCDM_BaseDriverPointer& theBaseDriver)
+{
+  TCollection_AsciiString aReadMagicNumber;
+
+  if (theIStream.good())
+  {
+    streampos aDocumentPos = theIStream.tellg();
+
+    // read magic number from the file
+    aReadMagicNumber = Storage_BaseDriver::ReadMagicNumber (theIStream);
+
+    if (!theIStream.good())
+    {
+      theIStream.clear();
+    }
+
+    theIStream.seekg(aDocumentPos);
+  }
+
+  if(aReadMagicNumber == FSD_CmpFile::MagicNumber())
+  {
+    theBaseDriver = new FSD_CmpFile;
+    return PCDM_TOFD_CmpFile;
+  }
+  else if (aReadMagicNumber == FSD_File::MagicNumber())
+  {
+    theBaseDriver = new FSD_File;
+    return PCDM_TOFD_File;
+  }
+  else if (aReadMagicNumber == FSD_BinaryFile::MagicNumber())
+  {
+    theBaseDriver = new FSD_BinaryFile;
+    return PCDM_TOFD_File;
+  }
+
+  theBaseDriver = NULL;
+  return PCDM_TOFD_Unknown;
+}
+

src/PCDM/PCDM.hxx

@@ -21,6 +21,8 @@
 #include <Standard_DefineAlloc.hxx>
 #include <Standard_Handle.hxx>
 
+#include <Standard_IStream.hxx>
+
 #include <Standard_Boolean.hxx>
 #include <PCDM_TypeOfFileDriver.hxx>
 #include <PCDM_BaseDriverPointer.hxx>
@@ -74,6 +76,8 @@ private:
 
   
   Standard_EXPORT static PCDM_TypeOfFileDriver FileDriverType (const TCollection_AsciiString& aFileName, PCDM_BaseDriverPointer& aBaseDriver);
+  
+  Standard_EXPORT static PCDM_TypeOfFileDriver FileDriverType (Standard_IStream& theIStream, PCDM_BaseDriverPointer& theBaseDriver);
 
 
 

src/PCDM/PCDM_ReadWriter.cxx

@@ -40,6 +40,8 @@ IMPLEMENT_STANDARD_RTTIEXT(PCDM_ReadWriter,Standard_Transient)
 static TCollection_ExtendedString TryXmlDriverType
                                 (const TCollection_AsciiString& theFileName);
 
+static TCollection_ExtendedString TryXmlDriverType (Standard_IStream& theIStream);
+
 //=======================================================================
 //function : Open
 //purpose  : 
@@ -151,6 +153,41 @@ TCollection_ExtendedString PCDM_ReadWriter::FileFormat
   return theFormat;
 }
 
+//=======================================================================
+//function : FileFormat
+//purpose  : 
+//=======================================================================
+
+TCollection_ExtendedString PCDM_ReadWriter::FileFormat (Standard_IStream& theIStream, Handle(Storage_Data)& theData)
+{
+  TCollection_ExtendedString aFormat;
+
+  Storage_BaseDriver* aFileDriver;
+  if (PCDM::FileDriverType (theIStream, aFileDriver) == PCDM_TOFD_Unknown)
+  {
+    return ::TryXmlDriverType (theIStream);
+  }
+  
+  // the stream starts with a magic number, FileDriverType has read
+  // them already but returned the stream pos to initial state,
+  // thus we should read them before reading of info section
+  aFileDriver->ReadMagicNumber(theIStream);
+
+  aFileDriver->ReadCompleteInfo (theIStream, theData);
+
+  for (Standard_Integer i = 1; i <= theData->HeaderData()->UserInfo().Length(); i++)
+  {
+    const TCollection_AsciiString& aLine = theData->HeaderData()->UserInfo().Value(i);
+
+    if(aLine.Search (FILE_FORMAT) != -1)
+    {
+      aFormat = TCollection_ExtendedString (aLine.Token(" ",2).ToCString(), Standard_True);
+    }
+  }
+
+  return aFormat;
+}
+
 //=======================================================================
 //function : ::TryXmlDriverType
 //purpose  : called from FileFormat()
@@ -174,3 +211,39 @@ static TCollection_ExtendedString TryXmlDriverType
   }
   return theFormat;
 }
+
+//=======================================================================
+//function : ::TryXmlDriverType
+//purpose  : called from FileFormat()
+//=======================================================================
+
+static TCollection_ExtendedString TryXmlDriverType (Standard_IStream& theIStream)
+{
+  TCollection_ExtendedString theFormat;
+  PCDM_DOMHeaderParser       aParser;
+  const char                 * aDocumentElementName = "document";
+  aParser.SetStartElementName (Standard_CString(aDocumentElementName));
+
+  if (theIStream.good())
+  {
+    streampos aDocumentPos = theIStream.tellg();
+
+    // Parse the file; if there is no error or an error appears before retrieval
+    // of the DocumentElement, the XML format cannot be defined
+    if (aParser.parse (theIStream))
+    {
+      LDOM_Element anElement = aParser.GetElement();
+      if (anElement.getTagName().equals (LDOMString(aDocumentElementName)))
+        theFormat = anElement.getAttribute ("format");
+    }
+
+    if (!theIStream.good())
+    {
+      theIStream.clear();
+    }
+
+    theIStream.seekg(aDocumentPos);
+  }
+
+  return theFormat;
+}

src/PCDM/PCDM_ReadWriter.hxx

@@ -76,6 +76,10 @@ public:
   //! a FileFormat information.
   Standard_EXPORT static TCollection_ExtendedString FileFormat (const TCollection_ExtendedString& aFileName);
 
+  //! tries  to get a format  from the stream.  returns an empty
+  //! string if the file could not be read or does not have
+  //! a FileFormat information.
+  Standard_EXPORT static TCollection_ExtendedString FileFormat (Standard_IStream& theIStream, Handle(Storage_Data)& theData);
 
 
 

src/PCDM/PCDM_Reader.hxx

@@ -22,6 +22,9 @@
 
 #include <PCDM_ReaderStatus.hxx>
 #include <Standard_Transient.hxx>
+#include <Standard_IStream.hxx>
+#include <Storage_Data.hxx>
+
 class PCDM_DriverError;
 class CDM_Document;
 class TCollection_ExtendedString;
@@ -43,6 +46,11 @@ public:
   
   //! retrieves the content of the file into a new Document.
   Standard_EXPORT virtual void Read (const TCollection_ExtendedString& aFileName, const Handle(CDM_Document)& aNewDocument, const Handle(CDM_Application)& anApplication) = 0;
+
+  Standard_EXPORT virtual void Read (Standard_IStream&               theIStream,
+                                      const Handle(Storage_Data)&    theStorageData,
+                                      const Handle(CDM_Document)&    theDoc,
+                                      const Handle(CDM_Application)& theApplication) = 0;
   
     PCDM_ReaderStatus GetStatus() const;
 

src/PCDM/PCDM_RetrievalDriver.cxx

@@ -69,6 +69,18 @@ void PCDM_RetrievalDriver::RaiseIfUnknownTypes(const Handle(Storage_Schema)& aSc
   }
 }
 
+//=======================================================================
+//function : Read
+//purpose  : 
+//=======================================================================
+void PCDM_RetrievalDriver::Read(Standard_IStream&               /*theIStream*/,
+                                const Handle(Storage_Data)&     /*theStorageData*/,
+                                const Handle(CDM_Document)&     /*theDoc*/,
+                                const Handle(CDM_Application)&  /*theApplication*/)
+{
+  
+}
+
 //=======================================================================
 //function : Read
 //purpose  : 

src/PCDM/PCDM_RetrievalDriver.hxx

@@ -56,6 +56,11 @@ public:
   //! into a persistent document. and the Make   method to build a
   //! transient document.
   Standard_EXPORT virtual void Read (const TCollection_ExtendedString& aFileName, const Handle(CDM_Document)& aNewDocument, const Handle(CDM_Application)& anApplication) Standard_OVERRIDE;
+
+  Standard_EXPORT virtual void Read (Standard_IStream&              theIStream,
+                                     const Handle(Storage_Data)&    theStorageData,
+                                     const Handle(CDM_Document)&    theDoc,
+                                     const Handle(CDM_Application)& theApplication) Standard_OVERRIDE;
   
   Standard_EXPORT virtual void Make (const Handle(PCDM_Document)& aPCDM, const Handle(CDM_Document)& aNewDocument) = 0;
   

src/PCDM/PCDM_StorageDriver.cxx

@@ -105,6 +105,15 @@ void PCDM_StorageDriver::Write(const Handle(CDM_Document)& aDocument, const TCol
     PCDM_DriverError::Raise(theData->ErrorStatusExtension().ToCString());
 }
 
+
+//=======================================================================
+//function : Write
+//purpose  : 
+//=======================================================================
+void PCDM_StorageDriver::Write (const Handle(CDM_Document)& /*aDocument*/, Standard_OStream& /*theOStream*/) 
+{
+  
+}
 //void PCDM_StorageDriver::LoadExtensions(const Handle(Storage_Schema)& aSchema, const TColStd_SequenceOfExtendedString& Extensions) {}
 void PCDM_StorageDriver::LoadExtensions(const Handle(Storage_Schema)& , const TColStd_SequenceOfExtendedString& ) {}
 

src/PCDM/PCDM_StorageDriver.hxx

@@ -75,6 +75,9 @@ public:
   //! by  default  Write will  use Make   method to build a persistent
   //! document and the Schema method to write the persistent document.
   Standard_EXPORT virtual void Write (const Handle(CDM_Document)& aDocument, const TCollection_ExtendedString& aFileName) Standard_OVERRIDE;
+
+  //! Write <theDocument> to theOStream
+  Standard_EXPORT virtual void Write (const Handle(CDM_Document)& theDocument, Standard_OStream& theOStream) Standard_OVERRIDE;
   
   Standard_EXPORT void SetFormat (const TCollection_ExtendedString& aformat);
   

src/PCDM/PCDM_Writer.hxx

@@ -38,6 +38,8 @@ public:
   
   Standard_EXPORT virtual void Write (const Handle(CDM_Document)& aDocument, const TCollection_ExtendedString& aFileName) = 0;
 
+  //! Write <theDocument> to theOStream
+  Standard_EXPORT virtual void Write (const Handle(CDM_Document)& theDocument, Standard_OStream& theOStream) = 0;