Introduce parent and child entries for MemEntryImpl...

net/disk_cache/mem_backend_impl.h

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2006-2009 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.
 
 // See net/disk_cache/disk_cache.h for the public interface of the cache.
 
 #ifndef NET_DISK_CACHE_MEM_BACKEND_IMPL_H__
 #define NET_DISK_CACHE_MEM_BACKEND_IMPL_H__
 
 #include "base/hash_tables.h"
 
 #include "net/disk_cache/disk_cache.h"
 #include "net/disk_cache/mem_rankings.h"
 
 namespace disk_cache {
 
 class MemEntryImpl;
 
 // This class implements the Backend interface. An object of this class handles
-// the operations of the cache without writting to disk.
+// the operations of the cache without writing to disk.
 class MemBackendImpl : public Backend {
  public:
   MemBackendImpl() : max_size_(0), current_size_(0) {}
   ~MemBackendImpl();
 
   // Performs general initialization for this current instance of the cache.
   bool Init();
 
   // Backend interface.
   virtual int32 GetEntryCount() const;
@@ skipping 17 matching lines @@
 
   // Updates the ranking information for an entry.
   void UpdateRank(MemEntryImpl* node);
 
   // A user data block is being created, extended or truncated.
   void ModifyStorageSize(int32 old_size, int32 new_size);
 
   // Returns the maximum size for a file to reside on the cache.
   int MaxFileSize() const;
 
+  // Insert an MemEntryImpl into the ranking list. This method is only called
+  // from MemEntryImpl to insert child entries. The reference can be removed
+  // by calling RemoveFromRankingList(|entry|).
+  void InsertIntoRankingList(MemEntryImpl* entry);
+
+  // Remove |entry| from ranking list. This method is only called from
+  // MemEntryImpl to remove a child entry from the ranking list.
+  void RemoveFromRankingList(MemEntryImpl* entry);
+
  private:
   // Deletes entries from the cache until the current size is below the limit.
   // If empty is true, the whole cache will be trimmed, regardless of being in
   // use.
   void TrimCache(bool empty);
 
   // Handles the used storage count.
   void AddStorageSize(int32 bytes);
   void SubstractStorageSize(int32 bytes);
 
   typedef base::hash_map<std::string, MemEntryImpl*> EntryMap;
 
   EntryMap entries_;
   MemRankings rankings_;  // Rankings to be able to trim the cache.
   int32 max_size_;        // Maximum data size for this instance.
   int32 current_size_;
 
   DISALLOW_EVIL_CONSTRUCTORS(MemBackendImpl);
 };
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_MEM_BACKEND_IMPL_H__