net/disk_cache/blockfile/file_block.h

   1 // Copyright (c) 2006-2008 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 of the cache.
   6
   7 #ifndef NET_DISK_CACHE_BLOCKFILE_FILE_BLOCK_H_
   8 #define NET_DISK_CACHE_BLOCKFILE_FILE_BLOCK_H_
   9
  10 namespace disk_cache {
  11
  12 // This interface exposes common functionality for a single block of data
  13 // stored on a file-block, regardless of the real type or size of the block.
  14 // Used to simplify loading / storing the block from disk.
  15 class FileBlock {
  16  public:
  17   virtual ~FileBlock() {}
  18
  19   // Returns a pointer to the actual data.
  20   virtual void* buffer() const = 0;
  21
  22   // Returns the size of the block;
  23   virtual size_t size() const = 0;
  24
  25   // Returns the file offset of this block.
  26   virtual int offset() const = 0;
  27 };
  28
  29 }  // namespace disk_cache
  30
  31 #endif  // NET_DISK_CACHE_BLOCKFILE_FILE_BLOCK_H_