Make CPDF_Object::GetString() a virtual method.

core/include/fpdfapi/fpdf_objects.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_INCLUDE_FPDFAPI_FPDF_OBJECTS_H_
 #define CORE_INCLUDE_FPDFAPI_FPDF_OBJECTS_H_
 
 #include "../fxcrt/fx_coordinates.h"
@@ skipping 23 matching lines @@
 #define PDFOBJ_ARRAY            5
 #define PDFOBJ_DICTIONARY       6
 #define PDFOBJ_STREAM           7
 #define PDFOBJ_NULL                     8
 #define PDFOBJ_REFERENCE        9
 
 typedef IFX_FileStream* (*FPDF_LPFCloneStreamCallback)(CPDF_Stream *pStream, void* pUserData);
 class CPDF_Object
 {
 public:
-
     int                                 GetType() const
     {
         return m_Type;
     }
 
     FX_DWORD                            GetObjNum() const
     {
         return m_ObjNum;
     }
 
     FX_DWORD                            GetGenNum() const
     {
         return m_GenNum;
     }
 
     FX_BOOL                             IsIdentical(CPDF_Object* pObj) const;
 
     CPDF_Object*                        Clone(FX_BOOL bDirect = FALSE) const;
 
     CPDF_Object*                        CloneRef(CPDF_IndirectObjects* pObjs) const;
 
     CPDF_Object*                        GetDirect() const;
 
     void                                Release();
 
-    CFX_ByteString                      GetString() const;
+    virtual CFX_ByteString GetString() const;
 
     CFX_ByteStringC                     GetConstString() const;
 
     CFX_WideString                      GetUnicodeText(CFX_CharMap* pCharMap = NULL) const;
     FX_FLOAT                            GetNumber() const;

[Tom Sepez, 2015/07/16 20:24:46]

There are a whole bunch of these that need to be virtualized.  Are you sure you
want to jump off this cliff right now?

 
     FX_FLOAT                            GetNumber16() const;
 
     int                                 GetInteger() const;
 
     CPDF_Dictionary*                    GetDict() const;
 
     CPDF_Array*                         GetArray() const;
 
     void                                SetString(const CFX_ByteString& str);
 
     void                                SetUnicodeText(const FX_WCHAR* pUnicodes, int len = -1);
 
     int                                 GetDirectType() const;
 
     FX_BOOL                             IsModified() const
     {
         return FALSE;
     }
 protected:
     CPDF_Object(FX_DWORD type) : m_Type(type), m_ObjNum(0), m_GenNum(0) { }
-    ~CPDF_Object() { }
+    virtual ~CPDF_Object() {}

[Tom Sepez, 2015/07/16 20:24:46]

Right, now that we are paying the price for a vtable this is OK, but why is it
still protected?

     void                                Destroy();

[Tom Sepez, 2015/07/16 20:24:46]

Remove Destroy() now that we have virtual destructors and update its callers.

 
     static const int                    OBJECT_REF_MAX_DEPTH = 128;
     static int                          s_nCurRefDepth;
     FX_DWORD                            m_Type;
     FX_DWORD                            m_ObjNum;
     FX_DWORD                            m_GenNum;
 
     friend class                        CPDF_IndirectObjects;
     friend class                        CPDF_Parser;
     friend class                        CPDF_SyntaxParser;
 private:
     CPDF_Object(const CPDF_Object& src) {}
     CPDF_Object* CloneInternal(FX_BOOL bDirect, CFX_MapPtrToPtr* visited) const;
 };
+
 class CPDF_Boolean : public CPDF_Object
 {
 public:
 
     static CPDF_Boolean*        Create(FX_BOOL value)
     {
         return new CPDF_Boolean(value);
     }
 
     CPDF_Boolean() : CPDF_Object(PDFOBJ_BOOLEAN), m_bValue(false) { }
     CPDF_Boolean(FX_BOOL value) : CPDF_Object(PDFOBJ_BOOLEAN), m_bValue(value) { }
+    ~CPDF_Boolean() override {}
 
     FX_BOOL                                     Identical(CPDF_Boolean* pOther) const
     {
         return m_bValue == pOther->m_bValue;
     }
 protected:
+    CFX_ByteString GetString() const override;
 
     FX_BOOL                                     m_bValue;
     friend class                        CPDF_Object;
 };
+
 class CPDF_Number : public CPDF_Object
 {
 public:
 
     static CPDF_Number*         Create(int value)
     {
         return new CPDF_Number(value);
     }
 
     static CPDF_Number*         Create(FX_FLOAT value)
@@ skipping 14 matching lines @@
     CPDF_Number() : CPDF_Object(PDFOBJ_NUMBER), m_bInteger(false), m_Integer(0) { }
 
     CPDF_Number(FX_BOOL bInteger, void* pData);
 
     CPDF_Number(int value);
 
     CPDF_Number(FX_FLOAT value);
 
     CPDF_Number(const CFX_ByteStringC& str);
 
+    ~CPDF_Number() override {}
+
     FX_BOOL                                     Identical(CPDF_Number* pOther) const;
 
-    CFX_ByteString                      GetString() const;
-
     void                                        SetString(const CFX_ByteStringC& str);
 
     FX_BOOL                                     IsInteger() const
     {
         return m_bInteger;
     }
 
     int                                         GetInteger() const
     {
         return m_bInteger ? m_Integer : (int)m_Float;
     }
 
     FX_FLOAT                            GetNumber() const
     {
         return m_bInteger ? (FX_FLOAT)m_Integer : m_Float;
     }
 
     void                                        SetNumber(FX_FLOAT value);
 
     FX_FLOAT                    GetNumber16() const
     {
         return GetNumber();
     }
 
     FX_FLOAT                            GetFloat() const
     {
         return m_bInteger ? (FX_FLOAT)m_Integer : m_Float;
     }
 protected:
+    CFX_ByteString GetString() const override;

[Tom Sepez, 2015/07/16 20:24:46]

not sure why this needs to be protected, either.

 
     FX_BOOL                                     m_bInteger;
 
     union {
 
         int                                     m_Integer;
 
         FX_FLOAT                        m_Float;
     };
     friend class                        CPDF_Object;
 };
+
 class CPDF_String : public CPDF_Object
 {
 public:
 
     static CPDF_String*         Create(const CFX_ByteString& str, FX_BOOL bHex = FALSE)
     {
         return new CPDF_String(str, bHex);
     }
 
     static CPDF_String*         Create(const CFX_WideString& str)
     {
         return new CPDF_String(str);
     }
 
     CPDF_String() : CPDF_Object(PDFOBJ_STRING), m_bHex(FALSE) { }
 
     CPDF_String(const CFX_ByteString& str, FX_BOOL bHex = FALSE)
         : CPDF_Object(PDFOBJ_STRING), m_String(str), m_bHex(bHex) {
     }
 
     CPDF_String(const CFX_WideString& str);
 
-    CFX_ByteString&                     GetString()
-    {
-        return m_String;
-    }
+    ~CPDF_String() override {}
 
     FX_BOOL                                     Identical(CPDF_String* pOther) const
     {
         return m_String == pOther->m_String;
     }
 
     FX_BOOL                                     IsHex() const
     {
         return m_bHex;
     }
 protected:
+    CFX_ByteString GetString() const override;

[Tom Sepez, 2015/07/16 20:24:46]

ditto

 
     CFX_ByteString                      m_String;
 
     FX_BOOL                                     m_bHex;
     friend class                        CPDF_Object;
 };
+
 class CPDF_Name : public CPDF_Object
 {
 public:
 
     static CPDF_Name*           Create(const CFX_ByteString& str)
     {
         return new CPDF_Name(str);
     }
 
     static CPDF_Name*           Create(const CFX_ByteStringC& str)
     {
         return new CPDF_Name(str);
     }
 
     static CPDF_Name*           Create(const FX_CHAR* str)
     {
         return new CPDF_Name(str);
     }
 
     CPDF_Name(const CFX_ByteString& str) : CPDF_Object(PDFOBJ_NAME), m_Name(str) { }
     CPDF_Name(const CFX_ByteStringC& str) : CPDF_Object(PDFOBJ_NAME), m_Name(str) { }
     CPDF_Name(const FX_CHAR* str) : CPDF_Object(PDFOBJ_NAME), m_Name(str) { }
+    ~CPDF_Name() override {}
 
     CFX_ByteString&                     GetString()
     {
         return m_Name;
     }
 
     FX_BOOL                                     Identical(CPDF_Name* pOther) const
     {
         return m_Name == pOther->m_Name;
     }
 protected:
+    CFX_ByteString GetString() const override;

[Tom Sepez, 2015/07/16 20:24:46]

ditto

 
     CFX_ByteString                      m_Name;
     friend class                        CPDF_Object;
 };
+
 class CPDF_Array : public CPDF_Object
 {
 public:
 
     static CPDF_Array*          Create()
     {
         return new CPDF_Array();
     }
 
     CPDF_Array() : CPDF_Object(PDFOBJ_ARRAY) { }
 
     FX_DWORD                            GetCount() const
     {
         return m_Objects.GetSize();
     }
 
     CPDF_Object*                        GetElement(FX_DWORD index) const;
 
     CPDF_Object*                        GetElementValue(FX_DWORD index) const;
 
 
 
     CFX_AffineMatrix            GetMatrix();
 
     CFX_FloatRect                       GetRect();
 
 
 
 
-    CFX_ByteString                      GetString(FX_DWORD index) const;
+    CFX_ByteString GetStringAt(FX_DWORD index) const;

[Tom Sepez, 2015/07/16 20:24:46]

I presume this is the overriding overloaded methods gotcha?  Either way, its a
better name.

 
     CFX_ByteStringC                     GetConstString(FX_DWORD index) const;
 
     int                                         GetInteger(FX_DWORD index) const;
 
     FX_FLOAT                            GetNumber(FX_DWORD index) const;
 
     CPDF_Dictionary*            GetDict(FX_DWORD index) const;
 
     CPDF_Stream*                        GetStream(FX_DWORD index) const;
@@ skipping 41 matching lines @@
         return GetNumber(index);
     }
 
     void                                        AddNumber16(FX_FLOAT value)
     {
         AddNumber(value);
     }
 
     FX_BOOL                                     Identical(CPDF_Array* pOther) const;
 protected:
-
-    ~CPDF_Array();
+    ~CPDF_Array() override;
 
     CFX_PtrArray                        m_Objects;
     friend class                        CPDF_Object;
 };
+
 class CPDF_Dictionary : public CPDF_Object
 {
 public:
 
     static CPDF_Dictionary*     Create()
     {
         return new CPDF_Dictionary();
     }
 
     CPDF_Dictionary() : CPDF_Object(PDFOBJ_DICTIONARY) { }
 
     CPDF_Object*                        GetElement(const CFX_ByteStringC& key) const;
 
     CPDF_Object*                        GetElementValue(const CFX_ByteStringC& key) const;
 
-
-
-
-
-    CFX_ByteString                      GetString(const CFX_ByteStringC& key) const;
+    CFX_ByteString GetStringAt(const CFX_ByteStringC& key) const;
 
     CFX_ByteStringC                     GetConstString(const CFX_ByteStringC& key) const;
 
-    CFX_ByteString                      GetString(const CFX_ByteStringC& key, const CFX_ByteStringC& default_str) const;
+    CFX_ByteString GetStringAt(const CFX_ByteStringC& key,
+                               const CFX_ByteStringC& default_str) const;
 
     CFX_ByteStringC                     GetConstString(const CFX_ByteStringC& key, const CFX_ByteStringC& default_str) const;
 
     CFX_WideString                      GetUnicodeText(const CFX_ByteStringC& key, CFX_CharMap* pCharMap = NULL) const;
 
     int                                         GetInteger(const CFX_ByteStringC& key) const;
 
     int                                         GetInteger(const CFX_ByteStringC& key, int default_int) const;
 
     FX_BOOL                                     GetBoolean(const CFX_ByteStringC& key, FX_BOOL bDefault = FALSE) const;
@@ skipping 66 matching lines @@
 
     FX_BOOL                                     Identical(CPDF_Dictionary* pDict) const;
 
     int                                         GetCount() const
     {
         return m_Map.GetCount();
     }
 
     void                                        AddValue(const CFX_ByteStringC& key, CPDF_Object* pObj);
 protected:
-
-    ~CPDF_Dictionary();
+    ~CPDF_Dictionary() override;
 
     CFX_CMapByteStringToPtr     m_Map;
 
     friend class                        CPDF_Object;
 };
+
 class CPDF_Stream : public CPDF_Object
 {
 public:
 
     static CPDF_Stream*         Create(uint8_t* pData, FX_DWORD size, CPDF_Dictionary* pDict)
     {
         return new CPDF_Stream(pData, size, pDict);
     }
 
     CPDF_Stream(uint8_t* pData, FX_DWORD size, CPDF_Dictionary* pDict);
@@ skipping 23 matching lines @@
     FX_BOOL                                     ReadRawData(FX_FILESIZE start_pos, uint8_t* pBuf, FX_DWORD buf_size) const;
 
 
     FX_BOOL                                     IsMemoryBased() const
     {
         return m_GenNum == (FX_DWORD) - 1;
     }
 
     CPDF_Stream*                        Clone(FX_BOOL bDirect, FPDF_LPFCloneStreamCallback lpfCallback, void* pUserData) const;
 protected:
-
-    ~CPDF_Stream();
+    ~CPDF_Stream() override;
 
     CPDF_Dictionary*            m_pDict;
 
     FX_DWORD                            m_dwSize;
 
     FX_DWORD                            m_GenNum;
 
     union {
 
         uint8_t*                        m_pDataBuf;
 
         IFX_FileRead*           m_pFile;
     };
 
     FX_FILESIZE                         m_FileOffset;
 
     CPDF_CryptoHandler*         m_pCryptoHandler;
 
     void                                        InitStream(CPDF_Dictionary* pDict);
     friend class                        CPDF_Object;
     friend class                        CPDF_StreamAcc;
     friend class                        CPDF_AttachmentAcc;
 };
+
 class CPDF_StreamAcc
 {
 public:
 
     CPDF_StreamAcc();
 
     ~CPDF_StreamAcc();
 
     void                                        LoadAllData(const CPDF_Stream* pStream, FX_BOOL bRawAccess = FALSE,
                                         FX_DWORD estimated_size = 0, FX_BOOL bImageAcc = FALSE);
@@ skipping 32 matching lines @@
     FX_BOOL                                     m_bNewBuf;
 
     CFX_ByteString                      m_ImageDecoder;
 
     CPDF_Dictionary*            m_pImageParam;
 
     const CPDF_Stream*          m_pStream;
 
     uint8_t*                            m_pSrcData;
 };
+
 CFX_DataFilter* FPDF_CreateFilter(const CFX_ByteStringC& name, const CPDF_Dictionary* pParam, int width = 0, int height = 0);
 #define FPDF_FILTER_BUFFER_SIZE         20480
 class CPDF_StreamFilter
 {
 public:
 
     ~CPDF_StreamFilter();
 
     FX_DWORD                    ReadBlock(uint8_t* buffer, FX_DWORD size);
 
@@ skipping 18 matching lines @@
 
     CFX_BinaryBuf*              m_pBuffer;
 
     FX_DWORD                    m_BufOffset;
 
     FX_DWORD                    m_SrcOffset;
 
     uint8_t                             m_SrcBuffer[FPDF_FILTER_BUFFER_SIZE];
     friend class CPDF_Stream;
 };
+
 class CPDF_Null : public CPDF_Object
 {
 public:
 
     static CPDF_Null*           Create()
     {
         return new CPDF_Null();
     }
 
     CPDF_Null() : CPDF_Object(PDFOBJ_NULL) { }
+    ~CPDF_Null() override {}
 };
+
 class CPDF_Reference : public CPDF_Object
 {
 public:
 
     static CPDF_Reference*      Create(CPDF_IndirectObjects* pDoc, int objnum)
     {
         return new CPDF_Reference(pDoc, objnum);
     }
 
     CPDF_Reference(CPDF_IndirectObjects* pDoc, int objnum)
         : CPDF_Object(PDFOBJ_REFERENCE), m_pObjList(pDoc), m_RefObjNum(objnum) {
     }
+    ~CPDF_Reference() override {}
 
     CPDF_IndirectObjects*       GetObjList() const
     {
         return m_pObjList;
     }
 
     FX_DWORD                            GetRefObjNum() const
     {
         return m_RefObjNum;
     }
 
     void                                        SetRef(CPDF_IndirectObjects* pDoc, FX_DWORD objnum);
 
     FX_BOOL                                     Identical(CPDF_Reference* pOther) const
     {
         return m_RefObjNum == pOther->m_RefObjNum;
     }
 protected:
+    CFX_ByteString GetString() const override;
 
     CPDF_IndirectObjects*       m_pObjList;
 
     FX_DWORD                            m_RefObjNum;
     friend class                        CPDF_Object;
 };
+
 class CPDF_IndirectObjects
 {
 public:
 
     CPDF_IndirectObjects(CPDF_Parser* pParser);
 
     ~CPDF_IndirectObjects();
 
     CPDF_Object*                        GetIndirectObject(FX_DWORD objnum, struct PARSE_CONTEXT* pContext = NULL);
 
@@ skipping 19 matching lines @@
 protected:
 
     CFX_MapPtrToPtr                     m_IndirectObjs;
 
     CPDF_Parser*                        m_pParser;
 
     FX_DWORD                            m_LastObjNum;
 };
 
 #endif  // CORE_INCLUDE_FPDFAPI_FPDF_OBJECTS_H_