storage/browser/quota/storage_observer.h

   1 // Copyright 2014 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 STORAGE_BROWSER_QUOTA_STORAGE_OBSERVER_H_
   6 #define STORAGE_BROWSER_QUOTA_STORAGE_OBSERVER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/time/time.h"
  10 #include "storage/browser/quota/quota_client.h"
  11 #include "storage/common/quota/quota_types.h"
  12 #include "url/gurl.h"
  13
  14 namespace storage {
  15
  16 // This interface is implemented by observers that wish to monitor storage
  17 // events, such as changes in quota or usage.
  18 class STORAGE_EXPORT StorageObserver {
  19  public:
  20   struct STORAGE_EXPORT Filter {
  21     // The storage type to monitor. This must not be kStorageTypeUnknown or
  22     // kStorageTypeQuotaNotManaged.
  23     StorageType storage_type;
  24
  25     // The origin to monitor usage for. Must be specified.
  26     GURL origin;
  27
  28     Filter();
  29     Filter(StorageType storage_type, const GURL& origin);
  30     bool operator==(const Filter& other) const;
  31   };
  32
  33   struct STORAGE_EXPORT MonitorParams {
  34     // Storage type and origin to monitor.
  35     Filter filter;
  36
  37     // The rate at which storage events will be fired. Events will be fired at
  38     // approximately this rate, or when a storage status change has been
  39     // detected, whichever is the least frequent.
  40     base::TimeDelta rate;
  41
  42     // If set to true, the observer will be dispatched an event when added.
  43     bool dispatch_initial_state;
  44
  45     MonitorParams();
  46     MonitorParams(StorageType storage_type,
  47                   const GURL& origin,
  48                   const base::TimeDelta& rate,
  49                   bool get_initial_state);
  50     MonitorParams(const Filter& filter,
  51                   const base::TimeDelta& rate,
  52                   bool get_initial_state);
  53   };
  54
  55   struct STORAGE_EXPORT Event {
  56     // The storage type and origin monitored.
  57     Filter filter;
  58
  59     // The current usage corresponding to the filter.
  60     int64 usage;
  61
  62     // The quota corresponding to the filter.
  63     int64 quota;
  64
  65     Event();
  66     Event(const Filter& filter, int64 usage, int64 quota);
  67     bool operator==(const Event& other) const;
  68   };
  69
  70   // Will be called on the IO thread when a storage event occurs.
  71   virtual void OnStorageEvent(const Event& event) = 0;
  72
  73  protected:
  74   virtual ~StorageObserver() {}
  75 };
  76
  77 }  // namespace storage
  78
  79 #endif  // STORAGE_BROWSER_QUOTA_STORAGE_OBSERVER_H_