Disk cache: Reference CL for the implementation of file format version 3.

net/disk_cache/backend_impl.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 of the cache.
 
 #ifndef NET_DISK_CACHE_BACKEND_IMPL_H_
 #define NET_DISK_CACHE_BACKEND_IMPL_H_
 
 #include "base/files/file_path.h"
 #include "base/hash_tables.h"
 #include "base/timer.h"
 #include "net/disk_cache/block_files.h"
 #include "net/disk_cache/disk_cache.h"
 #include "net/disk_cache/eviction.h"
 #include "net/disk_cache/in_flight_backend_io.h"
 #include "net/disk_cache/rankings.h"
 #include "net/disk_cache/stats.h"
 #include "net/disk_cache/stress_support.h"
 #include "net/disk_cache/trace.h"
 
 namespace net {
 class NetLog;
 }  // namespace net
 
 namespace disk_cache {
 
+struct Index;
+
 enum BackendFlags {
   kNone = 0,
   kMask = 1,                    // A mask (for the index table) was specified.
   kMaxSize = 1 << 1,            // A maximum size was provided.
   kUnitTestMode = 1 << 2,       // We are modifying the behavior for testing.
   kUpgradeMode = 1 << 3,        // This is the upgrade tool (dump).
   kNewEviction = 1 << 4,        // Use of new eviction was specified.
   kNoRandom = 1 << 5,           // Don't add randomness to the behavior.
   kNoLoadProtection = 1 << 6,   // Don't act conservatively under load.
   kNoBuffering = 1 << 7         // Disable extended IO buffering.
@@ skipping 235 matching lines @@
   virtual void OnExternalCacheHit(const std::string& key) OVERRIDE;
 
  private:
   typedef base::hash_map<CacheAddr, EntryImpl*> EntriesMap;
 
   // Creates a new backing file for the cache index.
   bool CreateBackingStore(disk_cache::File* file);
   bool InitBackingStore(bool* file_created);
   void AdjustMaxCacheSize(int table_len);
 
+  bool InitStats();
+  void StoreStats();
+
   // Deletes the cache and starts again.
   void RestartCache(bool failure);
   void PrepareForRestart();
 
   // Creates a new entry object. Returns zero on success, or a disk_cache error
   // on failure.
   int NewEntry(Addr address, EntryImpl** entry);
 
   // Returns a given entry from the cache. The entry to match is determined by
   // key and hash, and the returned entry may be the matched one or it's parent
@@ skipping 93 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(BackendImpl);
 };
 
 // Returns the preferred max cache size given the available disk space.
 NET_EXPORT_PRIVATE int PreferedCacheSize(int64 available);
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_BACKEND_IMPL_H_