Make CPDF_Object subclass constructors intern strings

core/fpdfapi/parser/cpdf_array.h

 // Copyright 2016 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
 
 #ifndef CORE_FPDFAPI_PARSER_CPDF_ARRAY_H_
 #define CORE_FPDFAPI_PARSER_CPDF_ARRAY_H_
 
 #include <memory>
 #include <set>
+#include <type_traits>
 #include <vector>
 
 #include "core/fpdfapi/parser/cpdf_indirect_object_holder.h"
 #include "core/fpdfapi/parser/cpdf_object.h"
 #include "core/fxcrt/fx_basic.h"
 #include "core/fxcrt/fx_coordinates.h"
 #include "third_party/base/ptr_util.h"
 
 class CPDF_Array : public CPDF_Object {
  public:
   using const_iterator =
       std::vector<std::unique_ptr<CPDF_Object>>::const_iterator;
 
   CPDF_Array();
+  explicit CPDF_Array(const CFX_WeakPtr<CFX_ByteStringPool>& pPool);
   ~CPDF_Array() override;
 
   // CPDF_Object:
   Type GetType() const override;
   std::unique_ptr<CPDF_Object> Clone() const override;
   bool IsArray() const override;
   CPDF_Array* AsArray() override;
   const CPDF_Array* AsArray() const override;
 
   bool IsEmpty() const { return m_Objects.empty(); }
   size_t GetCount() const { return m_Objects.size(); }
   CPDF_Object* GetObjectAt(size_t index) const;
   CPDF_Object* GetDirectObjectAt(size_t index) const;
   CFX_ByteString GetStringAt(size_t index) const;
   int GetIntegerAt(size_t index) const;
   FX_FLOAT GetNumberAt(size_t index) const;
   CPDF_Dictionary* GetDictAt(size_t index) const;
   CPDF_Stream* GetStreamAt(size_t index) const;
   CPDF_Array* GetArrayAt(size_t index) const;
   FX_FLOAT GetFloatAt(size_t index) const { return GetNumberAt(index); }
   CFX_Matrix GetMatrix();
   CFX_FloatRect GetRect();
 
   // Takes ownership of |pObj|, returns unowned pointer to it.
   CPDF_Object* Add(std::unique_ptr<CPDF_Object> pObj);
   CPDF_Object* SetAt(size_t index, std::unique_ptr<CPDF_Object> pObj);
   CPDF_Object* InsertAt(size_t index, std::unique_ptr<CPDF_Object> pObj);
 
   // Creates object owned by the array, returns unowned pointer to it.
+  // We have special cases for objects that can intern strings from
+  // a ByteStringPool.
   template <typename T, typename... Args>
-  T* AddNew(Args... args) {
+  typename std::enable_if<!CanInternStrings<T>::value, T*>::type AddNew(
+      Args... args) {
     return static_cast<T*>(Add(pdfium::MakeUnique<T>(args...)));
   }
   template <typename T, typename... Args>
-  T* SetNewAt(size_t index, Args... args) {
+  typename std::enable_if<CanInternStrings<T>::value, T*>::type AddNew(
+      Args... args) {
+    return static_cast<T*>(Add(pdfium::MakeUnique<T>(m_pPool, args...)));
+  }
+  template <typename T, typename... Args>
+  typename std::enable_if<!CanInternStrings<T>::value, T*>::type SetNewAt(
+      size_t index,
+      Args... args) {
     return static_cast<T*>(SetAt(index, pdfium::MakeUnique<T>(args...)));
   }
   template <typename T, typename... Args>
-  T* InsertNewAt(size_t index, Args... args) {
+  typename std::enable_if<CanInternStrings<T>::value, T*>::type SetNewAt(
+      size_t index,
+      Args... args) {
+    return static_cast<T*>(
+        SetAt(index, pdfium::MakeUnique<T>(m_pPool, args...)));
+  }
+  template <typename T, typename... Args>
+  typename std::enable_if<!CanInternStrings<T>::value, T*>::type InsertNewAt(
+      size_t index,
+      Args... args) {
     return static_cast<T*>(InsertAt(index, pdfium::MakeUnique<T>(args...)));
   }
+  template <typename T, typename... Args>
+  typename std::enable_if<CanInternStrings<T>::value, T*>::type InsertNewAt(
+      size_t index,
+      Args... args) {
+    return static_cast<T*>(
+        InsertAt(index, pdfium::MakeUnique<T>(m_pPool, args...)));
+  }
 
   void RemoveAt(size_t index, size_t nCount = 1);
   void ConvertToIndirectObjectAt(size_t index, CPDF_IndirectObjectHolder* pDoc);
 
   const_iterator begin() const { return m_Objects.begin(); }
   const_iterator end() const { return m_Objects.end(); }
 
  protected:
   std::unique_ptr<CPDF_Object> CloneNonCyclic(
       bool bDirect,
       std::set<const CPDF_Object*>* pVisited) const override;
 
   std::vector<std::unique_ptr<CPDF_Object>> m_Objects;
+  CFX_WeakPtr<CFX_ByteStringPool> m_pPool;
 };
 
 inline CPDF_Array* ToArray(CPDF_Object* obj) {
   return obj ? obj->AsArray() : nullptr;
 }
 
 inline const CPDF_Array* ToArray(const CPDF_Object* obj) {
   return obj ? obj->AsArray() : nullptr;
 }
 
 inline std::unique_ptr<CPDF_Array> ToArray(std::unique_ptr<CPDF_Object> obj) {
   CPDF_Array* pArray = ToArray(obj.get());
   if (!pArray)
     return nullptr;
   obj.release();
   return std::unique_ptr<CPDF_Array>(pArray);
 }
 
 #endif  // CORE_FPDFAPI_PARSER_CPDF_ARRAY_H_