Add type cast definitions for CPDF_String.

core/src/fpdfapi/fpdf_parser/fpdf_parser_objects.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 "../../../include/fpdfapi/fpdf_parser.h"
 #include "../../../include/fxcrt/fx_string.h"
 
 // static
 int CPDF_Object::s_nCurRefDepth = 0;
 
 void CPDF_Object::Release() {
   if (m_ObjNum) {
     return;
   }
   Destroy();
 }
 void CPDF_Object::Destroy() {
   switch (m_Type) {
     case PDFOBJ_STRING:
-      delete (CPDF_String*)this;
+      delete AsString();
       break;
     case PDFOBJ_NAME:
       delete (CPDF_Name*)this;
       break;
     case PDFOBJ_ARRAY:
       delete (CPDF_Array*)this;
       break;
     case PDFOBJ_DICTIONARY:
       delete AsDictionary();
       break;
     case PDFOBJ_STREAM:
       delete (CPDF_Stream*)this;
       break;
     default:
       delete this;
   }
 }
 CFX_ByteString CPDF_Object::GetString() const {
   switch (m_Type) {
     case PDFOBJ_BOOLEAN:
       return AsBoolean()->m_bValue ? "true" : "false";
     case PDFOBJ_NUMBER:
       return AsNumber()->GetString();
     case PDFOBJ_STRING:
-      return ((CPDF_String*)this)->m_String;
+      return AsString()->m_String;
     case PDFOBJ_NAME:
       return ((CPDF_Name*)this)->m_Name;
     case PDFOBJ_REFERENCE: {
       CPDF_Reference* pRef = (CPDF_Reference*)(void*)this;
       if (pRef->m_pObjList == NULL) {
         break;
       }
       CPDF_Object* pObj =
           pRef->m_pObjList->GetIndirectObject(pRef->GetRefObjNum());
       if (pObj == NULL) {
         return CFX_ByteString();
       }
       return pObj->GetString();
     }
   }
   return CFX_ByteString();
 }
 CFX_ByteStringC CPDF_Object::GetConstString() const {
   switch (m_Type) {
-    case PDFOBJ_STRING:
-      return CFX_ByteStringC((const uint8_t*)((CPDF_String*)this)->m_String,
-                             ((CPDF_String*)this)->m_String.GetLength());
+    case PDFOBJ_STRING: {
+      const CPDF_String* pString = AsString();

[Lei Zhang, 2015/10/21 16:55:56]

Maybe do AsString()->m_String here, instead of twice on the next 2 lines.

[dsinclair, 2015/10/21 17:08:05]

Done.

Good catch, missed the m_String duplication.

+      return CFX_ByteStringC((const uint8_t*)pString->m_String,
+                             pString->m_String.GetLength());
+    }
     case PDFOBJ_NAME:
       return CFX_ByteStringC((const uint8_t*)((CPDF_Name*)this)->m_Name,
                              ((CPDF_Name*)this)->m_Name.GetLength());
     case PDFOBJ_REFERENCE: {
       CPDF_Reference* pRef = (CPDF_Reference*)(void*)this;
       if (pRef->m_pObjList == NULL) {
         break;
       }
       CPDF_Object* pObj =
           pRef->m_pObjList->GetIndirectObject(pRef->GetRefObjNum());
@@ skipping 87 matching lines @@
 void CPDF_Object::SetString(const CFX_ByteString& str) {
   ASSERT(this != NULL);
   switch (m_Type) {
     case PDFOBJ_BOOLEAN:
       AsBoolean()->m_bValue = (str == FX_BSTRC("true"));
       return;
     case PDFOBJ_NUMBER:
       AsNumber()->SetString(str);
       return;
     case PDFOBJ_STRING:
-      ((CPDF_String*)this)->m_String = str;
+      AsString()->m_String = str;

[Tom Sepez, 2015/10/21 17:12:50]

nit: pity we don't have a SetString method as for numbers.

[dsinclair, 2015/10/21 17:40:01]

https://code.google.com/p/pdfium/issues/detail?id=240

       return;
     case PDFOBJ_NAME:
       ((CPDF_Name*)this)->m_Name = str;
       return;
   }
   ASSERT(FALSE);
 }
 int CPDF_Object::GetDirectType() const {
   if (m_Type != PDFOBJ_REFERENCE) {
     return m_Type;
@@ skipping 16 matching lines @@
       return IsIdentical(pOther->GetDirect());
     }
     return FALSE;
   }
   switch (m_Type) {
     case PDFOBJ_BOOLEAN:
       return AsBoolean()->Identical(pOther->AsBoolean());
     case PDFOBJ_NUMBER:
       return AsNumber()->Identical(pOther->AsNumber());
     case PDFOBJ_STRING:
-      return (((CPDF_String*)this)->Identical((CPDF_String*)pOther));
+      return AsString()->Identical(pOther->AsString());

[Tom Sepez, 2015/10/21 17:12:50]

Ok, I guess we checked for null above.

     case PDFOBJ_NAME:
       return (((CPDF_Name*)this)->Identical((CPDF_Name*)pOther));
     case PDFOBJ_ARRAY:
       return (((CPDF_Array*)this)->Identical((CPDF_Array*)pOther));
     case PDFOBJ_DICTIONARY:
       return AsDictionary()->Identical(pOther->AsDictionary());
     case PDFOBJ_NULL:
       return TRUE;
     case PDFOBJ_STREAM:
       return (((CPDF_Stream*)this)->Identical((CPDF_Stream*)pOther));
@@ skipping 19 matching lines @@
 CPDF_Object* CPDF_Object::CloneInternal(FX_BOOL bDirect,
                                         CFX_MapPtrToPtr* visited) const {
   switch (m_Type) {
     case PDFOBJ_BOOLEAN:
       return new CPDF_Boolean(AsBoolean()->m_bValue);
     case PDFOBJ_NUMBER: {
       const CPDF_Number* pThis = AsNumber();
       return new CPDF_Number(pThis->m_bInteger ? pThis->m_Integer
                                                : pThis->m_Float);
     }
-    case PDFOBJ_STRING:
-      return new CPDF_String(((CPDF_String*)this)->m_String,
-                             ((CPDF_String*)this)->IsHex());
+    case PDFOBJ_STRING: {
+      const CPDF_String* pString = AsString();
+      return new CPDF_String(pString->m_String, pString->IsHex());
+    }
     case PDFOBJ_NAME:
       return new CPDF_Name(((CPDF_Name*)this)->m_Name);
     case PDFOBJ_ARRAY: {
       CPDF_Array* pCopy = new CPDF_Array();
       CPDF_Array* pThis = (CPDF_Array*)this;
       int n = pThis->GetCount();
       for (int i = 0; i < n; i++) {
         CPDF_Object* value = (CPDF_Object*)pThis->m_Objects.GetAt(i);
         pCopy->m_Objects.Add(value->CloneInternal(bDirect, visited));
       }
@@ skipping 40 matching lines @@
   }
   return NULL;
 }
 CPDF_Object* CPDF_Object::CloneRef(CPDF_IndirectObjects* pDoc) const {
   if (m_ObjNum) {
     return new CPDF_Reference(pDoc, m_ObjNum);
   }
   return Clone();
 }
 CFX_WideString CPDF_Object::GetUnicodeText(CFX_CharMap* pCharMap) const {
-  if (m_Type == PDFOBJ_STRING) {
-    return PDF_DecodeText(((CPDF_String*)this)->m_String, pCharMap);
-  }
+  if (const CPDF_String* pString = AsString())
+    return PDF_DecodeText(pString->m_String, pCharMap);
+
   if (m_Type == PDFOBJ_STREAM) {
     CPDF_StreamAcc stream;
     stream.LoadAllData((CPDF_Stream*)this, FALSE);
     CFX_WideString result =
         PDF_DecodeText(stream.GetData(), stream.GetSize(), pCharMap);
     return result;
   }
   if (m_Type == PDFOBJ_NAME) {
     return PDF_DecodeText(((CPDF_Name*)this)->m_Name, pCharMap);
   }
   return CFX_WideString();
 }
 void CPDF_Object::SetUnicodeText(const FX_WCHAR* pUnicodes, int len) {
-  if (m_Type == PDFOBJ_STRING) {
-    ((CPDF_String*)this)->m_String = PDF_EncodeText(pUnicodes, len);
+  if (CPDF_String* pString = AsString()) {
+    pString->m_String = PDF_EncodeText(pUnicodes, len);
+

[Lei Zhang, 2015/10/21 16:55:56]

no blank line

[dsinclair, 2015/10/21 17:08:05]

Done.

   } else if (m_Type == PDFOBJ_STREAM) {
     CFX_ByteString result = PDF_EncodeText(pUnicodes, len);
     ((CPDF_Stream*)this)
         ->SetData((uint8_t*)result.c_str(), result.GetLength(), FALSE, FALSE);
   }
 }
 
 CPDF_Boolean* CPDF_Object::AsBoolean() {
   return IsBoolean() ? static_cast<CPDF_Boolean*>(this) : nullptr;
 }
@@ skipping 11 matching lines @@
 }
 
 CPDF_Number* CPDF_Object::AsNumber() {
   return IsNumber() ? static_cast<CPDF_Number*>(this) : nullptr;
 }
 
 const CPDF_Number* CPDF_Object::AsNumber() const {
   return IsNumber() ? static_cast<const CPDF_Number*>(this) : nullptr;
 }
 
+CPDF_String* CPDF_Object::AsString() {
+  return IsString() ? static_cast<CPDF_String*>(this) : nullptr;
+}
+
+const CPDF_String* CPDF_Object::AsString() const {
+  return IsString() ? static_cast<const CPDF_String*>(this) : nullptr;
+}
+
 CPDF_Number::CPDF_Number(int value)
     : CPDF_Object(PDFOBJ_NUMBER), m_bInteger(TRUE), m_Integer(value) {}
 
 CPDF_Number::CPDF_Number(FX_FLOAT value)
     : CPDF_Object(PDFOBJ_NUMBER), m_bInteger(FALSE), m_Float(value) {}
 
 CPDF_Number::CPDF_Number(const CFX_ByteStringC& str)
     : CPDF_Object(PDFOBJ_NUMBER) {
   FX_atonum(str, m_bInteger, &m_Integer);
 }
@@ skipping 844 matching lines @@
   }
   pObj->m_ObjNum = objnum;
   m_IndirectObjs.SetAt((void*)(uintptr_t)objnum, pObj);
   if (m_LastObjNum < objnum) {
     m_LastObjNum = objnum;
   }
 }
 FX_DWORD CPDF_IndirectObjects::GetLastObjNum() const {
   return m_LastObjNum;
 }