Revert of Class for allocating a chunk of memory for RenderPass

cc/quads/list_container.h

-// Copyright 2014 The Chromium 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 CC_QUADS_LIST_CONTAINER_H_
-#define CC_QUADS_LIST_CONTAINER_H_
-
-#include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
-#include "cc/base/cc_export.h"
-
-namespace cc {
-class SharedQuadState;
-class DrawQuad;
-
-// This class is a container type that handles allocating contiguous memory for
-// new elements and traversing through elements with either iterator or reverse
-// iterator. Since this container hands out raw pointers of its elements, it is
-// very important that this container never reallocate its memory so those raw
-// pointer will continue to be valid.  This class is used to contain
-// SharedQuadState or DrawQuad. Since the size of each DrawQuad varies, to hold
-// DrawQuads, the allocations size of each element in this class is
-// kLargestDrawQuad while BaseElementType is DrawQuad.
-template <class BaseElementType>
-class CC_EXPORT ListContainer {
- public:
-  // BaseElementType is the type of raw pointers this class hands out; however,
-  // its derived classes might require different memory sizes.
-  // max_size_for_derived_class the largest memory size required for all the
-  // derived classes to use for allocation.
-  explicit ListContainer(size_t max_size_for_derived_class);
-  // This constructor omits input variable for max_size_for_derived_class. This
-  // is used when there is no derived classes from BaseElementType we need to
-  // worry about, and allocation size is just sizeof(BaseElementType).
-  ListContainer();
-  // This constructor reserves the requested memory up front so only a single
-  // allocation is needed.
-  ListContainer(size_t max_size_for_derived_class,
-                size_t num_of_elements_to_reserve_for);
-
-  ~ListContainer();
-
-  // This class deals only with char* and void*. It does allocation and passing
-  // out raw pointers, as well as memory deallocation when being destroyed.
-  class CC_EXPORT ListContainerCharAllocator;
-
-  // This class points to a certain position inside memory of
-  // ListContainerCharAllocator. It is a base class for ListContainer iterators.
-  struct CC_EXPORT PositionInListContainerCharAllocator {
-    ListContainerCharAllocator* ptr_to_container;
-    size_t vector_index;
-    char* item_iterator;
-
-    PositionInListContainerCharAllocator(
-        const PositionInListContainerCharAllocator& other);
-
-    PositionInListContainerCharAllocator(ListContainerCharAllocator* container,
-                                         size_t vector_ind,
-                                         char* item_iter);
-
-    bool operator==(const PositionInListContainerCharAllocator& other) const;
-    bool operator!=(const PositionInListContainerCharAllocator& other) const;
-
-    PositionInListContainerCharAllocator Increment();
-    PositionInListContainerCharAllocator ReverseIncrement();
-  };
-
-  // Iterator classes that can be used to access data.
-  /////////////////////////////////////////////////////////////////
-  class CC_EXPORT Iterator : public PositionInListContainerCharAllocator {
-    // This class is only defined to forward iterate through
-    // ListContainerCharAllocator.
-   public:
-    Iterator(ListContainerCharAllocator* container,
-             size_t vector_ind,
-             char* item_iter);
-    ~Iterator();
-    BaseElementType* operator->() const;
-    BaseElementType& operator*() const;
-    Iterator operator++(int unused_post_increment);
-    Iterator operator++();
-  };
-
-  class CC_EXPORT ConstIterator : public PositionInListContainerCharAllocator {
-    // This class is only defined to forward iterate through
-    // ListContainerCharAllocator.
-   public:
-    ConstIterator(ListContainerCharAllocator* container,
-                  size_t vector_ind,
-                  char* item_iter);
-    ConstIterator(const Iterator& other);  // NOLINT
-    ~ConstIterator();
-    const BaseElementType* operator->() const;
-    const BaseElementType& operator*() const;
-    ConstIterator operator++(int unused_post_increment);
-    ConstIterator operator++();
-  };
-
-  class CC_EXPORT ReverseIterator
-      : public PositionInListContainerCharAllocator {
-    // This class is only defined to reverse iterate through
-    // ListContainerCharAllocator.
-   public:
-    ReverseIterator(ListContainerCharAllocator* container,
-                    size_t vector_ind,
-                    char* item_iter);
-    ~ReverseIterator();
-    BaseElementType* operator->() const;
-    BaseElementType& operator*() const;
-    ReverseIterator operator++(int unused_post_increment);
-    ReverseIterator operator++();
-  };
-
-  class CC_EXPORT ConstReverseIterator
-      : public PositionInListContainerCharAllocator {
-    // This class is only defined to reverse iterate through
-    // ListContainerCharAllocator.
-   public:
-    ConstReverseIterator(ListContainerCharAllocator* container,
-                         size_t vector_ind,
-                         char* item_iter);
-    ConstReverseIterator(const ReverseIterator& other);  // NOLINT
-    ~ConstReverseIterator();
-    const BaseElementType* operator->() const;
-    const BaseElementType& operator*() const;
-    ConstReverseIterator operator++(int unused_post_increment);
-    ConstReverseIterator operator++();
-  };
-
-  // When called, all raw pointers that have been handed out are no longer
-  // valid. Use with caution.
-  // This function does not deallocate memory.
-  void EraseAndInvalidateAllPointers(Iterator position);
-
-  ConstReverseIterator rbegin() const;
-  ConstReverseIterator rend() const;
-  ReverseIterator rbegin();
-  ReverseIterator rend();
-  ConstIterator begin() const;
-  ConstIterator end() const;
-  Iterator begin();
-  Iterator end();
-
-  BaseElementType* front();
-  BaseElementType* back();
-  const BaseElementType* front() const;
-  const BaseElementType* back() const;
-
-  // Take in derived element type and construct it at location generated by
-  // Allocate().
-  template <typename DerivedElementType>
-  DerivedElementType* AllocateAndConstruct() {
-    DerivedElementType* result =
-        new (Allocate(sizeof(DerivedElementType))) DerivedElementType;
-    return result;
-  }
-
-  size_t size() const;
-  bool empty() const;
-  void clear();
-
-  size_t AvailableSizeWithoutAnotherAllocationForTesting() const;
-
- private:
-  // Hands out memory location for an element at the end of data structure.
-  BaseElementType* Allocate(size_t size_of_actual_element_in_bytes);
-
-  scoped_ptr<ListContainerCharAllocator> data_;
-
-  DISALLOW_COPY_AND_ASSIGN(ListContainer);
-};
-
-#if !defined(COMPILER_MSVC)
-extern template class ListContainer<SharedQuadState>;
-extern template class ListContainer<DrawQuad>;
-#endif
-}  // namespace cc
-
-#endif  // CC_QUADS_LIST_CONTAINER_H_