Move SmartPointer to base.

src/smart-pointers.h

-// Copyright 2011 the V8 project authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef V8_SMART_POINTERS_H_
-#define V8_SMART_POINTERS_H_
-
-namespace v8 {
-namespace internal {
-
-
-template<typename Deallocator, typename T>
-class SmartPointerBase {
- public:
-  // Default constructor. Constructs an empty scoped pointer.
-  SmartPointerBase() : p_(NULL) {}
-
-  // Constructs a scoped pointer from a plain one.
-  explicit SmartPointerBase(T* ptr) : p_(ptr) {}
-
-  // Copy constructor removes the pointer from the original to avoid double
-  // freeing.
-  SmartPointerBase(const SmartPointerBase<Deallocator, T>& rhs)
-      : p_(rhs.p_) {
-    const_cast<SmartPointerBase<Deallocator, T>&>(rhs).p_ = NULL;
-  }
-
-  T* operator->() const { return p_; }
-
-  T& operator*() const { return *p_; }
-
-  T* get() const { return p_; }
-
-  // You can use [n] to index as if it was a plain pointer.
-  T& operator[](size_t i) {
-    return p_[i];
-  }
-
-  // You can use [n] to index as if it was a plain pointer.
-  const T& operator[](size_t i) const {
-    return p_[i];
-  }
-
-  // We don't have implicit conversion to a T* since that hinders migration:
-  // You would not be able to change a method from returning a T* to
-  // returning an SmartArrayPointer<T> and then get errors wherever it is used.
-
-
-  // If you want to take out the plain pointer and don't want it automatically
-  // deleted then call Detach().  Afterwards, the smart pointer is empty
-  // (NULL).
-  T* Detach() {
-    T* temp = p_;
-    p_ = NULL;
-    return temp;
-  }
-
-  void Reset(T* new_value) {
-    DCHECK(p_ == NULL || p_ != new_value);
-    if (p_) Deallocator::Delete(p_);
-    p_ = new_value;
-  }
-
-  // Assignment requires an empty (NULL) SmartArrayPointer as the receiver. Like
-  // the copy constructor it removes the pointer in the original to avoid
-  // double freeing.
-  SmartPointerBase<Deallocator, T>& operator=(
-      const SmartPointerBase<Deallocator, T>& rhs) {
-    DCHECK(is_empty());
-    T* tmp = rhs.p_;  // swap to handle self-assignment
-    const_cast<SmartPointerBase<Deallocator, T>&>(rhs).p_ = NULL;
-    p_ = tmp;
-    return *this;
-  }
-
-  bool is_empty() const { return p_ == NULL; }
-
- protected:
-  // When the destructor of the scoped pointer is executed the plain pointer
-  // is deleted using DeleteArray.  This implies that you must allocate with
-  // NewArray.
-  ~SmartPointerBase() { if (p_) Deallocator::Delete(p_); }
-
- private:
-  T* p_;
-};
-
-// A 'scoped array pointer' that calls DeleteArray on its pointer when the
-// destructor is called.
-
-template<typename T>
-struct ArrayDeallocator {
-  static void Delete(T* array) {
-    DeleteArray(array);
-  }
-};
-
-
-template<typename T>
-class SmartArrayPointer: public SmartPointerBase<ArrayDeallocator<T>, T> {
- public:
-  SmartArrayPointer() { }
-  explicit SmartArrayPointer(T* ptr)
-      : SmartPointerBase<ArrayDeallocator<T>, T>(ptr) { }
-  SmartArrayPointer(const SmartArrayPointer<T>& rhs)
-      : SmartPointerBase<ArrayDeallocator<T>, T>(rhs) { }
-};
-
-
-template<typename T>
-struct ObjectDeallocator {
-  static void Delete(T* object) {
-    delete object;
-  }
-};
-
-
-template<typename T>
-class SmartPointer: public SmartPointerBase<ObjectDeallocator<T>, T> {
- public:
-  SmartPointer() { }
-  explicit SmartPointer(T* ptr)
-      : SmartPointerBase<ObjectDeallocator<T>, T>(ptr) { }
-  SmartPointer(const SmartPointer<T>& rhs)
-      : SmartPointerBase<ObjectDeallocator<T>, T>(rhs) { }
-};
-
-} }  // namespace v8::internal
-
-#endif  // V8_SMART_POINTERS_H_