Fix memory leaks involving InsertIndirectObject()

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 "core/include/fpdfapi/fpdf_parser.h"
 
 #include "core/include/fxcrt/fx_string.h"
 
@@ skipping 1138 matching lines @@
 void CPDF_IndirectObjects::ReleaseIndirectObject(FX_DWORD objnum) {
   void* value;
   if (!m_IndirectObjs.Lookup((void*)(uintptr_t)objnum, value))
     return;
   CPDF_Object* pValue = static_cast<CPDF_Object*>(value);
   if (pValue->GetObjNum() == -1)
     return;
   pValue->Destroy();
   m_IndirectObjs.RemoveKey((void*)(uintptr_t)objnum);
 }
-void CPDF_IndirectObjects::InsertIndirectObject(FX_DWORD objnum,
-                                                CPDF_Object* pObj) {
-  if (objnum == 0 || pObj == NULL) {
-    return;
-  }
-  void* value = NULL;
-  if (m_IndirectObjs.Lookup((void*)(uintptr_t)objnum, value)) {
-    if (value) {
-      CPDF_Object* pValue = static_cast<CPDF_Object*>(value);
-      if (pObj->GetGenNum() <= pValue->GetGenNum())
-        return;
-      pValue->Destroy();
+FX_BOOL CPDF_IndirectObjects::InsertIndirectObject(FX_DWORD objnum,
+                                                   CPDF_Object* pObj) {
+  if (!objnum || !pObj)
+    return FALSE;
+  void* pExistingObj = nullptr;

[Tom Sepez, 2015/12/11 00:15:07]

I'd have kept value here, ...

[jun_fang, 2015/12/11 02:07:16]

Acknowledged.

+  if (m_IndirectObjs.Lookup((void*)(uintptr_t)objnum, pExistingObj)) {
+    if (pExistingObj) {

[Tom Sepez, 2015/12/11 00:15:07]

and declared pExistingObj here with the static cast ...

[jun_fang, 2015/12/11 02:07:16]

Acknowledged.

+      if (pObj->GetGenNum() <=
+          static_cast<CPDF_Object*>(pExistingObj)->GetGenNum()) {
+        pObj->Destroy();
+        return FALSE;
+      }
+      static_cast<CPDF_Object*>(pExistingObj)->Destroy();

[Tom Sepez, 2015/12/11 00:15:07]

which avoids having to write static_cast twice.

[jun_fang, 2015/12/11 02:07:16]

Acknowledged.

     }
   }
   pObj->m_ObjNum = objnum;
   m_IndirectObjs.SetAt((void*)(uintptr_t)objnum, pObj);
-  if (m_LastObjNum < objnum) {
+  if (m_LastObjNum < objnum)
     m_LastObjNum = objnum;
-  }
+  return TRUE;
 }
 FX_DWORD CPDF_IndirectObjects::GetLastObjNum() const {
   return m_LastObjNum;
 }