Make CPDF_Object::GetString() a virtual method.

core/include/fpdfapi/fpdf_objects.h

Index: core/include/fpdfapi/fpdf_objects.h
diff --git a/core/include/fpdfapi/fpdf_objects.h b/core/include/fpdfapi/fpdf_objects.h
index 570dc410c208c0a14559a6602286498b54f5eadc..81bb3ff3ecc65ab0a12761ea2af8ee0e66503a63 100644
--- a/core/include/fpdfapi/fpdf_objects.h
+++ b/core/include/fpdfapi/fpdf_objects.h
@@ -41,7 +41,6 @@ typedef IFX_FileStream* (*FPDF_LPFCloneStreamCallback)(CPDF_Stream *pStream, voi
 class CPDF_Object
 {
 public:
-
     int                                 GetType() const
     {
         return m_Type;
@@ -67,7 +66,7 @@ public:
 
     void                                Release();
 
-    CFX_ByteString                      GetString() const;
+    virtual CFX_ByteString GetString() const;
 
     CFX_ByteStringC                     GetConstString() const;
 
@@ -94,7 +93,7 @@ public:
     }
 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;
@@ -110,6 +109,7 @@ private:
     CPDF_Object(const CPDF_Object& src) {}
     CPDF_Object* CloneInternal(FX_BOOL bDirect, CFX_MapPtrToPtr* visited) const;
 };
+
 class CPDF_Boolean : public CPDF_Object
 {
 public:
@@ -121,16 +121,19 @@ public:
 
     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:
@@ -165,9 +168,9 @@ public:
 
     CPDF_Number(const CFX_ByteStringC& str);
 
-    FX_BOOL					Identical(CPDF_Number* pOther) const;
+    ~CPDF_Number() override {}
 
-    CFX_ByteString			GetString() const;
+    FX_BOOL					Identical(CPDF_Number* pOther) const;
 
     void					SetString(const CFX_ByteStringC& str);
 
@@ -198,6 +201,7 @@ public:
         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;
 
@@ -209,6 +213,7 @@ protected:
     };
     friend class			CPDF_Object;
 };
+
 class CPDF_String : public CPDF_Object
 {
 public:
@@ -231,10 +236,7 @@ public:
 
     CPDF_String(const CFX_WideString& str);
 
-    CFX_ByteString&			GetString()
-    {
-        return m_String;
-    }
+    ~CPDF_String() override {}
 
     FX_BOOL					Identical(CPDF_String* pOther) const
     {
@@ -246,12 +248,14 @@ public:
         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:
@@ -274,6 +278,7 @@ public:
     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()
     {
@@ -285,10 +290,12 @@ public:
         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:
@@ -318,7 +325,7 @@ public:
 
 
 
-    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;
 
@@ -380,12 +387,12 @@ public:
 
     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:
@@ -401,15 +408,12 @@ public:
 
     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;
 
@@ -496,13 +500,13 @@ public:
 
     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:
@@ -546,8 +550,7 @@ public:
 
     CPDF_Stream*			Clone(FX_BOOL bDirect, FPDF_LPFCloneStreamCallback lpfCallback, void* pUserData) const;
 protected:
-
-    ~CPDF_Stream();
+    ~CPDF_Stream() override;
 
     CPDF_Dictionary*		m_pDict;
 
@@ -571,6 +574,7 @@ protected:
     friend class			CPDF_StreamAcc;
     friend class			CPDF_AttachmentAcc;
 };
+
 class CPDF_StreamAcc
 {
 public:
@@ -623,6 +627,7 @@ protected:
 
     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
@@ -661,6 +666,7 @@ protected:
     uint8_t				m_SrcBuffer[FPDF_FILTER_BUFFER_SIZE];
     friend class CPDF_Stream;
 };
+
 class CPDF_Null : public CPDF_Object
 {
 public:
@@ -671,7 +677,9 @@ public:
     }
 
     CPDF_Null() : CPDF_Object(PDFOBJ_NULL) { }
+    ~CPDF_Null() override {}
 };
+
 class CPDF_Reference : public CPDF_Object
 {
 public:
@@ -684,6 +692,7 @@ public:
     CPDF_Reference(CPDF_IndirectObjects* pDoc, int objnum)
         : CPDF_Object(PDFOBJ_REFERENCE), m_pObjList(pDoc), m_RefObjNum(objnum) {
     }
+    ~CPDF_Reference() override {}
 
     CPDF_IndirectObjects*	GetObjList() const
     {
@@ -702,12 +711,14 @@ public:
         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: