Add type cast definitions for CPDF_Array.

core/src/fpdfapi/fpdf_parser/fpdf_parser_decode.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 <limits.h>
 #include "../../../include/fpdfapi/fpdf_parser.h"
 #include "../../../include/fpdfapi/fpdf_module.h"
 #include "../../../include/fxcodec/fx_codec.h"
@@ skipping 313 matching lines @@
                        const CPDF_Dictionary* pDict,
                        uint8_t*& dest_buf,
                        FX_DWORD& dest_size,
                        CFX_ByteString& ImageEncoding,
                        CPDF_Dictionary*& pImageParms,
                        FX_DWORD last_estimated_size,
                        FX_BOOL bImageAcc)
 
 {
   CPDF_Object* pDecoder =
-      pDict ? pDict->GetElementValue(FX_BSTRC("Filter")) : NULL;
-  if (!pDecoder || (pDecoder->GetType() != PDFOBJ_ARRAY && !pDecoder->IsName()))
+      pDict ? pDict->GetElementValue(FX_BSTRC("Filter")) : nullptr;
+  if (!pDecoder || (!pDecoder->IsArray() && !pDecoder->IsName()))
     return FALSE;
 
   CPDF_Object* pParams =
-      pDict ? pDict->GetElementValue(FX_BSTRC("DecodeParms")) : NULL;
+      pDict ? pDict->GetElementValue(FX_BSTRC("DecodeParms")) : nullptr;
   CFX_ByteStringArray DecoderList;
   CFX_PtrArray ParamList;
-  if (pDecoder->GetType() == PDFOBJ_ARRAY) {
-    if (pParams && pParams->GetType() != PDFOBJ_ARRAY) {
-      pParams = NULL;
-    }
-    CPDF_Array* pDecoders = (CPDF_Array*)pDecoder;
+  if (CPDF_Array* pDecoders = pDecoder->AsArray()) {
+    CPDF_Array* pParamsArray = ToArray(pParams);
+    if (!pParamsArray)
+      pParams = nullptr;
+
     for (FX_DWORD i = 0; i < pDecoders->GetCount(); i++) {
       CFX_ByteStringC str = pDecoders->GetConstString(i);
       DecoderList.Add(str);
-      if (pParams) {
-        ParamList.Add(((CPDF_Array*)pParams)->GetDict(i));
-      } else {
-        ParamList.Add(NULL);
-      }
+      ParamList.Add(pParams ? pParamsArray->GetDict(i) : nullptr);
     }
   } else {
     DecoderList.Add(pDecoder->GetConstString());
-    ParamList.Add(pParams ? pParams->GetDict() : NULL);
+    ParamList.Add(pParams ? pParams->GetDict() : nullptr);
   }
   uint8_t* last_buf = (uint8_t*)src_buf;
   FX_DWORD last_size = src_size;
   for (int i = 0; i < DecoderList.GetSize(); i++) {
     int estimated_size =
         i == DecoderList.GetSize() - 1 ? last_estimated_size : 0;
     CFX_ByteString decoder = DecoderList[i];
     // Use ToDictionary here because we can push NULL into the ParamList.
     CPDF_Dictionary* pParam =
         ToDictionary(static_cast<CPDF_Object*>(ParamList[i]));
@@ skipping 208 matching lines @@
                      FX_DWORD src_size,
                      uint8_t*& dest_buf,
                      FX_DWORD& dest_size) {
   CCodec_ModuleMgr* pEncoders = CPDF_ModuleMgr::Get()->GetCodecModule();
   if (pEncoders) {
     return pEncoders->GetFlateModule()->FlateOrLZWDecode(
         FALSE, src_buf, src_size, FALSE, 0, 0, 0, 0, 0, dest_buf, dest_size);
   }
   return 0;
 }