Remove the flash specific disk cache backend.

net/disk_cache/flash/log_store.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.
-
-#ifndef NET_DISK_CACHE_FLASH_LOG_STORE_H_
-#define NET_DISK_CACHE_FLASH_LOG_STORE_H_
-
-#include <set>
-#include <vector>
-
-#include "base/basictypes.h"
-#include "base/gtest_prod_util.h"
-#include "net/base/net_export.h"
-#include "net/disk_cache/flash/storage.h"
-
-namespace disk_cache {
-
-class Segment;
-
-// This class implements a general purpose store for storing and retrieving
-// entries consisting of arbitrary binary data.  The store has log semantics,
-// i.e. it's not possible to overwrite data in place.  In order to update an
-// entry, a new version must be written.  Only one entry can be written to at
-// any given time, while concurrent reading of multiple entries is supported.
-class NET_EXPORT_PRIVATE LogStore {
- public:
-  LogStore(const base::FilePath& path, int32 size);
-  ~LogStore();
-
-  // Performs initialization.  Must be the first function called and further
-  // calls should be made only if it is successful.
-  bool Init();
-
-  // Closes the store.  Should be the last function called before destruction.
-  bool Close();
-
-  // Creates an entry of |size| bytes.  The id of the created entry is stored in
-  // |entry_id|.
-  bool CreateEntry(int32 size, int32* entry_id);
-
-  // Deletes |entry_id|; the client should keep track of |size| and provide it
-  // here.  Only inactive (i.e. not currently open or being created) entries can
-  // be deleted.
-  void DeleteEntry(int32 entry_id, int32 size);
-
-  // Appends data to the end of the last created entry.
-  bool WriteData(const void* buffer, int32 size);
-
-  // Opens an entry with id |entry_id|.
-  bool OpenEntry(int32 entry_id);
-
-  // Reads |size| bytes starting from |offset| into |buffer|, where |offset| is
-  // relative to the entry's content, from an entry identified by |entry_id|.
-  bool ReadData(int32 entry_id, void* buffer, int32 size, int32 offset) const;
-
-  // Closes an entry that was either opened with OpenEntry or created with
-  // CreateEntry.
-  void CloseEntry(int32 id);
-
- private:
-  FRIEND_TEST_ALL_PREFIXES(FlashCacheTest, LogStoreReadFromClosedSegment);
-  FRIEND_TEST_ALL_PREFIXES(FlashCacheTest, LogStoreSegmentSelectionIsFifo);
-  FRIEND_TEST_ALL_PREFIXES(FlashCacheTest, LogStoreInUseSegmentIsSkipped);
-  FRIEND_TEST_ALL_PREFIXES(FlashCacheTest, LogStoreReadFromCurrentAfterClose);
-
-  int32 GetNextSegmentIndex();
-  bool InUse(int32 segment_index) const;
-
-  Storage storage_;
-
-  int32 num_segments_;
-
-  // Currently open segments, either for reading or writing.  There can only be
-  // one segment open for writing, and multiple open for reading.
-  std::vector<Segment*> open_segments_;
-
-  // The index of the segment currently being written to.  It's an index to
-  // |open_segments_| vector.
-  int32 write_index_;
-
-  // Ids of entries currently open, either CreatEntry'ed or OpenEntry'ed.
-  std::set<int32> open_entries_;
-
-  // Id of the entry that is currently being written to, -1 if there is no entry
-  // currently being written to.
-  int32 current_entry_id_;
-
-  // Number of bytes left to be written to the entry identified by
-  // |current_entry_id_|.  Its value makes sense iff |current_entry_id_| is not
-  // -1.
-  int32 current_entry_num_bytes_left_to_write_;
-
-  bool init_;  // Init was called.
-  bool closed_;  // Close was called.
-
-  DISALLOW_COPY_AND_ASSIGN(LogStore);
-};
-
-}  // namespace disk_cache
-
-#endif  // NET_DISK_CACHE_FLASH_LOG_STORE_H_