Call CXFA_Object::ToNode() rather than C-style casting.

xfa/src/fxfa/src/app/xfa_ffdoc.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "xfa/src/foxitlib.h"
 #include "xfa/src/fxfa/src/common/xfa_common.h"
 #include "xfa_ffapp.h"
 #include "xfa_ffdoc.h"
@@ skipping 82 matching lines @@
       pNewRoot->RemoveChild(pChildNode);
       pOriginRoot->InsertChild(pChildNode);
       pChildNode = pNextSibling;
       pNextSibling = NULL;
     }
   }
 }
 int32_t CXFA_FFDoc::DoLoad(IFX_Pause* pPause) {
   int32_t iStatus = m_pDocument->GetParser()->DoParse(pPause);
   if (iStatus == XFA_PARSESTATUS_Done && !m_pPDFDoc) {
-    CXFA_Node* pPDFNode =
-        (CXFA_Node*)m_pDocument->GetXFAObject(XFA_HASHCODE_Pdf);
+    CXFA_Node* pPDFNode = ToNode(m_pDocument->GetXFAObject(XFA_HASHCODE_Pdf));
     if (!pPDFNode) {
       return XFA_PARSESTATUS_SyntaxErr;
     }
     IFDE_XMLNode* pPDFXML = pPDFNode->GetXMLMappingNode();
     if (pPDFXML->GetType() != FDE_XMLNODE_Element) {
       return XFA_PARSESTATUS_SyntaxErr;
     }
     int32_t iBufferSize = 0;
     uint8_t* pByteBuffer = NULL;
     IFX_FileRead* pXFAReader = NULL;
@@ skipping 38 matching lines @@
       iStatus = XFA_PARSESTATUS_StatusErr;
     }
     pParser->Release();
     pParser = NULL;
   }
   return iStatus;
 }
 void CXFA_FFDoc::StopLoad() {
   m_pApp->GetXFAFontMgr()->LoadDocFonts(this);
   m_dwDocType = XFA_DOCTYPE_Static;
-  CXFA_Node* pConfig =
-      (CXFA_Node*)m_pDocument->GetXFAObject(XFA_HASHCODE_Config);
+  CXFA_Node* pConfig = ToNode(m_pDocument->GetXFAObject(XFA_HASHCODE_Config));
   if (!pConfig) {
     return;
   }
   CXFA_Node* pAcrobat = pConfig->GetFirstChildByClass(XFA_ELEMENT_Acrobat);
   if (!pAcrobat) {
     return;
   }
   CXFA_Node* pAcrobat7 = pAcrobat->GetFirstChildByClass(XFA_ELEMENT_Acrobat7);
   if (!pAcrobat7) {
     return;
@@ skipping 215 matching lines @@
     imageDIBDpi->iImageXDpi = iImageXDpi;
     imageDIBDpi->iImageYDpi = iImageYDpi;
     pImageFileRead->Release();
   }
   m_mapNamedImages.SetAt((void*)(uintptr_t)dwHash, imageDIBDpi);
   return (CFX_DIBitmap*)imageDIBDpi->pDibSource;
 }
 IFDE_XMLElement* CXFA_FFDoc::GetPackageData(const CFX_WideStringC& wsPackage) {
   FX_DWORD packetHash =
       FX_HashCode_String_GetW(wsPackage.GetPtr(), wsPackage.GetLength());
-  CXFA_Object* pObject = m_pDocument->GetXFAObject(packetHash);
-  CXFA_Node* pNode =
-      (pObject && pObject->IsNode()) ? (CXFA_Node*)pObject : NULL;
+  CXFA_Node* pNode = ToNode(m_pDocument->GetXFAObject(packetHash));
   if (!pNode) {
     return NULL;
   }
   IFDE_XMLNode* pXMLNode = pNode->GetXMLMappingNode();
   return (pXMLNode && pXMLNode->GetType() == FDE_XMLNODE_Element)
              ? (IFDE_XMLElement*)pXMLNode
              : NULL;
 }
 FX_BOOL CXFA_FFDoc::SavePackage(const CFX_WideStringC& wsPackage,
                                 IFX_FileWrite* pFile,
                                 IXFA_ChecksumContext* pCSContext) {
   IXFA_PacketExport* pExport = IXFA_PacketExport::Create(m_pDocument);
   if (!pExport) {
     return FALSE;
   }
   FX_DWORD packetHash =
       FX_HashCode_String_GetW(wsPackage.GetPtr(), wsPackage.GetLength());
   CXFA_Node* pNode = NULL;
   if (packetHash == XFA_HASHCODE_Xfa) {
     pNode = m_pDocument->GetRoot();
   } else {
-    CXFA_Object* pObject = m_pDocument->GetXFAObject(packetHash);
-    pNode = (pObject && pObject->IsNode()) ? (CXFA_Node*)pObject : NULL;
+    pNode = ToNode(m_pDocument->GetXFAObject(packetHash));
   }
   FX_BOOL bFlags = FALSE;
   if (pNode) {
     CFX_ByteString bsChecksum;
     if (pCSContext) {
       pCSContext->GetChecksum(bsChecksum);
     }
     bFlags = pExport->Export(pFile, pNode, 0, bsChecksum.GetLength()
                                                   ? (const FX_CHAR*)bsChecksum
                                                   : NULL);
   } else {
     bFlags = pExport->Export(pFile);
   }
   pExport->Release();
   return bFlags;
 }
 FX_BOOL CXFA_FFDoc::ImportData(IFX_FileRead* pStream, FX_BOOL bXDP) {
   FX_BOOL bRet = FALSE;
   IXFA_PacketImport* pImport = IXFA_PacketImport::Create(m_pDocument);
   if (pImport) {
     bRet = pImport->ImportData(pStream);
     pImport->Release();
   }
   return bRet;
 }