Support linearized loading

core/src/fpdfapi/fpdf_parser/parser_int.h

+// 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
+
+#ifndef CORE_SRC_FPDFAPI_FPDF_PARSER_PARSER_INT_H_
+#define CORE_SRC_FPDFAPI_FPDF_PARSER_PARSER_INT_H_
+
+class CPDF_DataAvail;
+
+class CPDF_HintTables {
+ public:
+  CPDF_HintTables(CPDF_DataAvail* pDataAvail, CPDF_Dictionary* pLinearized)
+      : m_pLinearizedDict(pLinearized),
+        m_pHintStream(nullptr),
+        m_pDataAvail(pDataAvail),
+        m_nFirstPageSharedObjs(0),
+        m_szFirstPageObjOffset(0) {}
+  ~CPDF_HintTables();
+  FX_BOOL GetPagePos(int index,
+                     FX_FILESIZE& szPageStartPos,
+                     FX_FILESIZE& szPageLength,
+                     FX_DWORD& dwObjNum);
+  FX_BOOL CheckPage(int index, IFX_DownloadHints* pHints);
+  FX_BOOL LoadHintStream(CPDF_Stream* pHintStream);
+
+ protected:
+  FX_BOOL ReadPageHintTable(CFX_BitStream* hStream);
+  FX_BOOL ReadSharedObjHintTable(CFX_BitStream* hStream);
+  FX_DWORD GetItemLength(int index, const CFX_FileSizeArray& szArray);
+
+ private:
+  int ReadPrimaryHintStreamOffset() const;
+  int ReadPrimaryHintStreamLength() const;
+
+  CPDF_Dictionary* m_pLinearizedDict;
+  CPDF_Stream* m_pHintStream;
+  CPDF_DataAvail* m_pDataAvail;
+  FX_DWORD m_nFirstPageSharedObjs;
+  FX_FILESIZE m_szFirstPageObjOffset;
+  CFX_DWordArray m_dwDeltaNObjsArray;
+  CFX_DWordArray m_dwNSharedObjsArray;
+  CFX_DWordArray m_dwSharedObjNumArray;
+  CFX_DWordArray m_dwIdentifierArray;
+  CFX_FileSizeArray m_szPageOffsetArray;
+  CFX_FileSizeArray m_szSharedObjOffsetArray;
+};
+#endif  // CORE_SRC_FPDFAPI_FPDF_PARSER_PARSER_INT_H_