1// Copyright (c) 2010 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// See net/disk_cache/disk_cache.h for the public interface.
6
7#ifndef NET_DISK_CACHE_MEMORY_MEM_RANKINGS_H_
8#define NET_DISK_CACHE_MEMORY_MEM_RANKINGS_H_
9
10#include "base/basictypes.h"
11
12namespace disk_cache {
13
14class MemEntryImpl;
15
16// This class handles the ranking information for the memory-only cache.
17class MemRankings {
18 public:
19  MemRankings() : head_(NULL), tail_(NULL) {}
20  ~MemRankings();
21
22  // Inserts a given entry at the head of the queue.
23  void Insert(MemEntryImpl* node);
24
25  // Removes a given entry from the LRU list.
26  void Remove(MemEntryImpl* node);
27
28  // Moves a given entry to the head.
29  void UpdateRank(MemEntryImpl* node);
30
31  // Iterates through the list.
32  MemEntryImpl* GetNext(MemEntryImpl* node);
33  MemEntryImpl* GetPrev(MemEntryImpl* node);
34
35 private:
36  MemEntryImpl* head_;
37  MemEntryImpl* tail_;
38
39  DISALLOW_COPY_AND_ASSIGN(MemRankings);
40};
41
42}  // namespace disk_cache
43
44#endif  // NET_DISK_CACHE_MEMORY_MEM_RANKINGS_H_
45