net/disk_cache/v3/eviction_v3.h

   1 // Copyright (c) 2012 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 #ifndef NET_DISK_CACHE_EVICTION_H_
   6 #define NET_DISK_CACHE_EVICTION_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/weak_ptr.h"
  10 #include "net/disk_cache/disk_format.h"
  11 #include "net/disk_cache/rankings.h"
  12
  13 namespace disk_cache {
  14
  15 class BackendImpl;
  16 class EntryImpl;
  17
  18 // This class implements the eviction algorithm for the cache and it is tightly
  19 // integrated with BackendImpl.
  20 class Eviction {
  21  public:
  22   Eviction();
  23   ~Eviction();
  24
  25   void Init(BackendImpl* backend);
  26   void Stop();
  27
  28   // Deletes entries from the cache until the current size is below the limit.
  29   // If empty is true, the whole cache will be trimmed, regardless of being in
  30   // use.
  31   void TrimCache(bool empty);
  32
  33   // Notifications of interesting events for a given entry.
  34   void OnOpenEntry(EntryImpl* entry);
  35   void OnCreateEntry(EntryImpl* entry);
  36
  37   // Testing interface.
  38   void SetTestMode();
  39   void TrimDeletedList(bool empty);
  40
  41  private:
  42   void PostDelayedTrim();
  43   void DelayedTrim();
  44   bool ShouldTrim();
  45   bool ShouldTrimDeleted();
  46   bool EvictEntry(CacheRankingsBlock* node, bool empty, Rankings::List list);
  47
  48   void TrimCacheV2(bool empty);
  49   void TrimDeleted(bool empty);
  50
  51   bool NodeIsOldEnough(CacheRankingsBlock* node, int list);
  52   int SelectListByLength(Rankings::ScopedRankingsBlock* next);
  53   void ReportListStats();
  54
  55   BackendImpl* backend_;
  56   Rankings* rankings_;
  57   IndexHeader* header_;
  58   int max_size_;
  59   int trim_delays_;
  60   int index_size_;
  61   bool new_eviction_;
  62   bool first_trim_;
  63   bool trimming_;
  64   bool delay_trim_;
  65   bool init_;
  66   bool test_mode_;
  67   base::WeakPtrFactory<Eviction> ptr_factory_;
  68
  69   DISALLOW_COPY_AND_ASSIGN(Eviction);
  70 };
  71
  72 }  // namespace disk_cache
  73
  74 #endif  // NET_DISK_CACHE_EVICTION_H_