storage/browser/quota/special_storage_policy.h

   1 // Copyright 2013 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_SPECIAL_STORAGE_POLICY_H_
   6 #define STORAGE_BROWSER_QUOTA_SPECIAL_STORAGE_POLICY_H_
   7
   8 #include <string>
   9
  10 #include "base/memory/ref_counted.h"
  11 #include "base/observer_list.h"
  12 #include "storage/browser/storage_browser_export.h"
  13
  14 class GURL;
  15
  16 namespace storage {
  17
  18 // Special rights are granted to 'extensions' and 'applications'. The
  19 // storage subsystems query this interface to determine which origins
  20 // have these rights. Chrome provides an impl that is cognizant of what
  21 // is currently installed in the extensions system.
  22 // The IsSomething() methods must be thread-safe, however Observers should
  23 // only be notified, added, and removed on the IO thead.
  24 class STORAGE_EXPORT SpecialStoragePolicy
  25     : public base::RefCountedThreadSafe<SpecialStoragePolicy> {
  26  public:
  27   typedef int StoragePolicy;
  28   enum ChangeFlags {
  29     STORAGE_PROTECTED = 1 << 0,
  30     STORAGE_UNLIMITED = 1 << 1,
  31   };
  32
  33   class STORAGE_EXPORT Observer {
  34    public:
  35     virtual void OnGranted(const GURL& origin, int change_flags) = 0;
  36     virtual void OnRevoked(const GURL& origin, int change_flags) = 0;
  37     virtual void OnCleared() = 0;
  38
  39    protected:
  40     virtual ~Observer();
  41   };
  42
  43   SpecialStoragePolicy();
  44
  45   // Protected storage is not subject to removal by the browsing data remover.
  46   virtual bool IsStorageProtected(const GURL& origin) = 0;
  47
  48   // Unlimited storage is not subject to quota or storage pressure eviction.
  49   virtual bool IsStorageUnlimited(const GURL& origin) = 0;
  50
  51   // Durable storage is not subject to storage pressure eviction.
  52   virtual bool IsStorageDurable(const GURL& origin) = 0;
  53
  54   // Some origins (e.g. installed apps) have access to the size of the remaining
  55   // disk capacity.
  56   virtual bool CanQueryDiskSize(const GURL& origin) = 0;
  57
  58   // Checks if the origin contains per-site isolated storage.
  59   virtual bool HasIsolatedStorage(const GURL& origin) = 0;
  60
  61   // Some origins are only allowed to store session-only data which is deleted
  62   // when the session ends.
  63   virtual bool IsStorageSessionOnly(const GURL& origin) = 0;
  64
  65   // Returns true if some origins are only allowed session-only storage.
  66   virtual bool HasSessionOnlyOrigins() = 0;
  67
  68   // Adds/removes an observer, the policy does not take
  69   // ownership of the observer. Should only be called on the IO thread.
  70   void AddObserver(Observer* observer);
  71   void RemoveObserver(Observer* observer);
  72
  73  protected:
  74   friend class base::RefCountedThreadSafe<SpecialStoragePolicy>;
  75   virtual ~SpecialStoragePolicy();
  76   void NotifyGranted(const GURL& origin, int change_flags);
  77   void NotifyRevoked(const GURL& origin, int change_flags);
  78   void NotifyCleared();
  79
  80   base::ObserverList<Observer> observers_;
  81 };
  82
  83 }  // namespace storage
  84
  85 #endif  // STORAGE_BROWSER_QUOTA_SPECIAL_STORAGE_POLICY_H_