Add type cast definitions for CPDF_Array.

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 AsString();
       break;
     case PDFOBJ_NAME:
       delete AsName();
       break;
     case PDFOBJ_ARRAY:
-      delete (CPDF_Array*)this;
+      delete AsArray();
       break;
     case PDFOBJ_DICTIONARY:
       delete AsDictionary();
       break;
     case PDFOBJ_STREAM:
       delete (CPDF_Stream*)this;
       break;
     default:
       delete this;
   }
@@ skipping 115 matching lines @@
       if (!pObj || (pObj == this))
         return nullptr;
       return pObj->GetDict();
     }
     default:
       return nullptr;
   }
 }
 
 CPDF_Array* CPDF_Object::GetArray() const {
-  if (m_Type == PDFOBJ_ARRAY)
-    return (CPDF_Array*)this;
-
-  return NULL;
+  // The method should be made non-const if we want to not be const.
+  // See bug #234.
+  return const_cast<CPDF_Array*>(AsArray());
 }
 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;
@@ skipping 32 matching lines @@
   switch (m_Type) {
     case PDFOBJ_BOOLEAN:
       return AsBoolean()->Identical(pOther->AsBoolean());
     case PDFOBJ_NUMBER:
       return AsNumber()->Identical(pOther->AsNumber());
     case PDFOBJ_STRING:
       return AsString()->Identical(pOther->AsString());
     case PDFOBJ_NAME:
       return AsName()->Identical(pOther->AsName());
     case PDFOBJ_ARRAY:
-      return (((CPDF_Array*)this)->Identical((CPDF_Array*)pOther));
+      return AsArray()->Identical(pOther->AsArray());
     case PDFOBJ_DICTIONARY:
       return AsDictionary()->Identical(pOther->AsDictionary());
     case PDFOBJ_NULL:
       return TRUE;
     case PDFOBJ_STREAM:
       return (((CPDF_Stream*)this)->Identical((CPDF_Stream*)pOther));
     case PDFOBJ_REFERENCE:
       return (((CPDF_Reference*)this)->Identical((CPDF_Reference*)pOther));
   }
   return FALSE;
@@ skipping 23 matching lines @@
                                                : pThis->m_Float);
     }
     case PDFOBJ_STRING: {
       const CPDF_String* pString = AsString();
       return new CPDF_String(pString->m_String, pString->IsHex());
     }
     case PDFOBJ_NAME:
       return new CPDF_Name(AsName()->m_Name);
     case PDFOBJ_ARRAY: {
       CPDF_Array* pCopy = new CPDF_Array();
-      CPDF_Array* pThis = (CPDF_Array*)this;
+      const CPDF_Array* pThis = AsArray();
       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));
       }
       return pCopy;
     }
     case PDFOBJ_DICTIONARY: {
       CPDF_Dictionary* pCopy = new CPDF_Dictionary();
       const CPDF_Dictionary* pThis = AsDictionary();
@@ skipping 59 matching lines @@
 void CPDF_Object::SetUnicodeText(const FX_WCHAR* pUnicodes, int len) {
   if (CPDF_String* pString = AsString()) {
     pString->m_String = PDF_EncodeText(pUnicodes, len);
   } 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_Array* CPDF_Object::AsArray() {
+  return IsArray() ? static_cast<CPDF_Array*>(this) : nullptr;
+}
+
+const CPDF_Array* CPDF_Object::AsArray() const {
+  return IsArray() ? static_cast<const CPDF_Array*>(this) : nullptr;
+}
+
 CPDF_Boolean* CPDF_Object::AsBoolean() {
   return IsBoolean() ? static_cast<CPDF_Boolean*>(this) : nullptr;
 }
 
 const CPDF_Boolean* CPDF_Object::AsBoolean() const {
   return IsBoolean() ? static_cast<const CPDF_Boolean*>(this) : nullptr;
 }
 
 CPDF_Dictionary* CPDF_Object::AsDictionary() {
   return IsDictionary() ? static_cast<CPDF_Dictionary*>(this) : nullptr;
@@ skipping 59 matching lines @@
 CPDF_Array::~CPDF_Array() {
   int size = m_Objects.GetSize();
   CPDF_Object** pList = (CPDF_Object**)m_Objects.GetData();
   for (int i = 0; i < size; i++) {
     if (pList[i])
       pList[i]->Release();
   }
 }
 CFX_FloatRect CPDF_Array::GetRect() {
   CFX_FloatRect rect;
-  if (m_Type != PDFOBJ_ARRAY || m_Objects.GetSize() != 4) {
+  if (!IsArray() || m_Objects.GetSize() != 4)
     return rect;
-  }
+
   rect.left = GetNumber(0);
   rect.bottom = GetNumber(1);
   rect.right = GetNumber(2);
   rect.top = GetNumber(3);
   return rect;
 }
 CFX_AffineMatrix CPDF_Array::GetMatrix() {
   CFX_AffineMatrix matrix;
-  if (m_Type != PDFOBJ_ARRAY || m_Objects.GetSize() != 6) {
+  if (!IsArray() || m_Objects.GetSize() != 6)
     return matrix;
-  }
+
   matrix.Set(GetNumber(0), GetNumber(1), GetNumber(2), GetNumber(3),
              GetNumber(4), GetNumber(5));
   return matrix;
 }
 CPDF_Object* CPDF_Array::GetElement(FX_DWORD i) const {
   if (i >= (FX_DWORD)m_Objects.GetSize()) {
     return NULL;
   }
   return (CPDF_Object*)m_Objects.GetAt(i);
 }
@@ skipping 45 matching lines @@
   return NULL;
 }
 CPDF_Stream* CPDF_Array::GetStream(FX_DWORD i) const {
   CPDF_Object* p = GetElementValue(i);
   if (p == NULL || p->GetType() != PDFOBJ_STREAM) {
     return NULL;
   }
   return (CPDF_Stream*)p;
 }
 CPDF_Array* CPDF_Array::GetArray(FX_DWORD i) const {
-  CPDF_Object* p = GetElementValue(i);
-  if (p == NULL || p->GetType() != PDFOBJ_ARRAY) {
-    return NULL;
-  }
-  return (CPDF_Array*)p;
+  return ToArray(GetElementValue(i));
 }
 void CPDF_Array::RemoveAt(FX_DWORD i) {
-  ASSERT(m_Type == PDFOBJ_ARRAY);
+  ASSERT(IsArray());
   if (i >= (FX_DWORD)m_Objects.GetSize()) {
     return;
   }
   CPDF_Object* p = (CPDF_Object*)m_Objects.GetAt(i);
   if (p)
     p->Release();
   m_Objects.RemoveAt(i);
 }
 void CPDF_Array::SetAt(FX_DWORD i,
                        CPDF_Object* pObj,
                        CPDF_IndirectObjects* pObjs) {
-  ASSERT(m_Type == PDFOBJ_ARRAY);
+  ASSERT(IsArray());
   ASSERT(i < (FX_DWORD)m_Objects.GetSize());
   if (i >= (FX_DWORD)m_Objects.GetSize()) {
     return;
   }
   CPDF_Object* pOld = (CPDF_Object*)m_Objects.GetAt(i);
   if (pOld)
     pOld->Release();
   if (pObj->GetObjNum()) {
     ASSERT(pObjs != NULL);
     pObj = new CPDF_Reference(pObjs, pObj->GetObjNum());
@@ skipping 12 matching lines @@
 }
 void CPDF_Array::Add(CPDF_Object* pObj, CPDF_IndirectObjects* pObjs) {
   ASSERT(pObj != NULL);
   if (pObj->GetObjNum()) {
     ASSERT(pObjs != NULL);
     pObj = new CPDF_Reference(pObjs, pObj->GetObjNum());
   }
   m_Objects.Add(pObj);
 }
 void CPDF_Array::AddName(const CFX_ByteString& str) {
-  ASSERT(m_Type == PDFOBJ_ARRAY);
+  ASSERT(IsArray());
   Add(new CPDF_Name(str));
 }
 void CPDF_Array::AddString(const CFX_ByteString& str) {
-  ASSERT(m_Type == PDFOBJ_ARRAY);
+  ASSERT(IsArray());
   Add(new CPDF_String(str));
 }
 void CPDF_Array::AddInteger(int i) {
-  ASSERT(m_Type == PDFOBJ_ARRAY);
+  ASSERT(IsArray());
   Add(new CPDF_Number(i));
 }
 void CPDF_Array::AddNumber(FX_FLOAT f) {
-  ASSERT(m_Type == PDFOBJ_ARRAY);
+  ASSERT(IsArray());
   CPDF_Number* pNumber = new CPDF_Number;
   pNumber->SetNumber(f);
   Add(pNumber);
 }
 void CPDF_Array::AddReference(CPDF_IndirectObjects* pDoc, FX_DWORD objnum) {
-  ASSERT(m_Type == PDFOBJ_ARRAY);
+  ASSERT(IsArray());
   Add(new CPDF_Reference(pDoc, objnum));
 }
 FX_BOOL CPDF_Array::Identical(CPDF_Array* pOther) const {
   if (m_Objects.GetSize() != pOther->m_Objects.GetSize()) {
     return FALSE;
   }
   for (int i = 0; i < m_Objects.GetSize(); i++)
     if (!((CPDF_Object*)m_Objects[i])
              ->IsIdentical((CPDF_Object*)pOther->m_Objects[i])) {
       return FALSE;
@@ skipping 122 matching lines @@
   }
   if (CPDF_Dictionary* pDict = p->AsDictionary()) {
     return pDict;
   }
   if (p->GetType() == PDFOBJ_STREAM) {
     return ((CPDF_Stream*)p)->GetDict();
   }
   return nullptr;
 }
 CPDF_Array* CPDF_Dictionary::GetArray(const CFX_ByteStringC& key) const {
-  CPDF_Object* p = GetElementValue(key);
-  if (p == NULL || p->GetType() != PDFOBJ_ARRAY) {
-    return NULL;
-  }
-  return (CPDF_Array*)p;
+  return ToArray(GetElementValue(key));
 }
 CPDF_Stream* CPDF_Dictionary::GetStream(const CFX_ByteStringC& key) const {
   CPDF_Object* p = GetElementValue(key);
   if (p == NULL || p->GetType() != PDFOBJ_STREAM) {
     return NULL;
   }
   return (CPDF_Stream*)p;
 }
 CFX_FloatRect CPDF_Dictionary::GetRect(const CFX_ByteStringC& key) const {
   CFX_FloatRect rect;
@@ skipping 508 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;
 }