Disk cache v3 ref2

net/disk_cache/v3/block_bitmaps.h

 // Copyright (c) 2012 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.
 
 #ifndef NET_DISK_CACHE_V3_BLOCK_BITMAPS_H_
 #define NET_DISK_CACHE_V3_BLOCK_BITMAPS_H_
 
 #include "base/files/file_path.h"
+#include "base/gtest_prod_util.h"
+#include "base/memory/scoped_ptr.h"
 #include "net/base/net_export.h"
 #include "net/disk_cache/addr.h"
 #include "net/disk_cache/block_files.h"
+#include "net/disk_cache/mapped_file.h"
 
 namespace disk_cache {
 
 class BackendImplV3;
 
 // This class is the interface in the v3 disk cache to the set of files holding
 // cached data that is small enough to not be efficiently stored in a dedicated
 // file (i.e. < kMaxBlockSize). It is primarily used to allocate and free
 // regions in those files used to store data.
 class NET_EXPORT_PRIVATE BlockBitmaps {
  public:
-  BlockBitmaps();
+  explicit BlockBitmaps(BackendImplV3* backend);
   ~BlockBitmaps();
 
   void Init(const BlockFilesBitmaps& bitmaps);
 
   // Creates a new entry on a block file. block_type indicates the size of block
   // to be used (as defined on cache_addr.h), block_count is the number of
   // blocks to allocate, and block_address is the address of the new entry.
   bool CreateBlock(FileType block_type, int block_count, Addr* block_address);
 
   // Removes an entry from the block files.
   void DeleteBlock(Addr address);
 
   // Releases the internal bitmaps. The cache is being purged.
   void Clear();
 
   // Sends UMA stats.
   void ReportStats();
 
   // Returns true if the blocks pointed by a given address are currently used.
   // This method is only intended for debugging.
   bool IsValid(Addr address);
 
  private:
   // Returns the header number that stores a given address.
   int GetHeaderNumber(Addr address);
 
+  // Returns the number of entry blocks for the given file type.
+  int EmptyBlocksForType(int first_file);
+
   // Returns the appropriate header to use for a new block.
   int HeaderNumberForNewBlock(FileType block_type, int block_count);
 
   // Retrieves stats for the given file index.
   void GetFileStats(int index, int* used_count, int* load);
 
   BlockFilesBitmaps bitmaps_;
+  BackendImplV3* backend_;
+  int empty_counts_[kFirstAdditionalBlockFileV3];
 
   DISALLOW_COPY_AND_ASSIGN(BlockBitmaps);
 };
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_V3_BLOCK_BITMAPS_H_