Fix stack overflow in object Clone() functions

core/fpdfapi/fpdf_parser/include/cpdf_object.h

Index: core/fpdfapi/fpdf_parser/include/cpdf_object.h
diff --git a/core/fpdfapi/fpdf_parser/include/cpdf_object.h b/core/fpdfapi/fpdf_parser/include/cpdf_object.h
index 86f3879ce1fffa3243c01cf6c59f04512d72c198..57fdb3abeaf40510b69ef9c9ccd63dbf814dce5f 100644
--- a/core/fpdfapi/fpdf_parser/include/cpdf_object.h
+++ b/core/fpdfapi/fpdf_parser/include/cpdf_object.h
@@ -7,6 +7,8 @@
 #ifndef CORE_FPDFAPI_FPDF_PARSER_INCLUDE_CPDF_OBJECT_H_
 #define CORE_FPDFAPI_FPDF_PARSER_INCLUDE_CPDF_OBJECT_H_
 
+#include <set>
+
 #include "core/fxcrt/include/fx_string.h"
 #include "core/fxcrt/include/fx_system.h"
 
@@ -39,7 +41,13 @@ class CPDF_Object {
   uint32_t GetObjNum() const { return m_ObjNum; }
   uint32_t GetGenNum() const { return m_GenNum; }
 
-  virtual CPDF_Object* Clone(FX_BOOL bDirect = FALSE) const = 0;
+  virtual CPDF_Object* Clone() const = 0;

[Lei Zhang, 2016/08/18 15:16:44]

It would be good to document what the different Clone methods do.

[Wei Li, 2016/08/18 22:02:30]

Done.

+  virtual CPDF_Object* CloneDeRef(bool bDirect) const;

[Lei Zhang, 2016/08/18 15:16:44]

Does anyone override this?

[Wei Li, 2016/08/18 22:02:30]

Not now, but it could be.

+  // Complex objects should implement their own CloneWithCheck()
+  // function to properly check for possible loop.
+  virtual CPDF_Object* CloneWithCheck(
+      bool bDirect,
+      std::set<const CPDF_Object*>* pVisited) const;
   virtual CPDF_Object* GetDirect() const;
 
   void Release();