storage/browser/fileapi/quota/quota_reservation_manager.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_FILEAPI_QUOTA_QUOTA_RESERVATION_MANAGER_H_
   6 #define STORAGE_BROWSER_FILEAPI_QUOTA_QUOTA_RESERVATION_MANAGER_H_
   7
   8 #include <map>
   9 #include <utility>
  10
  11 #include "base/basictypes.h"
  12 #include "base/callback_forward.h"
  13 #include "base/files/file.h"
  14 #include "base/memory/ref_counted.h"
  15 #include "base/memory/weak_ptr.h"
  16 #include "storage/browser/storage_browser_export.h"
  17 #include "storage/common/fileapi/file_system_types.h"
  18 #include "url/gurl.h"
  19
  20 namespace content {
  21 class QuotaReservationManagerTest;
  22 }
  23
  24 namespace storage {
  25
  26 class QuotaReservation;
  27 class QuotaReservationBuffer;
  28 class OpenFileHandle;
  29 class OpenFileHandleContext;
  30
  31 class STORAGE_EXPORT QuotaReservationManager {
  32  public:
  33   // Callback for ReserveQuota. When this callback returns false, ReserveQuota
  34   // operation should be reverted.
  35   typedef base::Callback<bool(base::File::Error error, int64 delta)>
  36       ReserveQuotaCallback;
  37
  38   // An abstraction of backing quota system.
  39   class STORAGE_EXPORT QuotaBackend {
  40    public:
  41     QuotaBackend() {}
  42     virtual ~QuotaBackend() {}
  43
  44     // Reserves or reclaims |delta| of quota for |origin| and |type| pair.
  45     // Reserved quota should be counted as usage, but it should be on-memory
  46     // and be cleared by a browser restart.
  47     // Invokes |callback| upon completion with an error code.
  48     // |callback| should return false if it can't accept the reservation, in
  49     // that case, the backend should roll back the reservation.
  50     virtual void ReserveQuota(const GURL& origin,
  51                               FileSystemType type,
  52                               int64 delta,
  53                               const ReserveQuotaCallback& callback) = 0;
  54
  55     // Reclaims |size| of quota for |origin| and |type|.
  56     virtual void ReleaseReservedQuota(const GURL& origin,
  57                                       FileSystemType type,
  58                                       int64 size) = 0;
  59
  60     // Updates disk usage of |origin| and |type|.
  61     // Invokes |callback| upon completion with an error code.
  62     virtual void CommitQuotaUsage(const GURL& origin,
  63                                   FileSystemType type,
  64                                   int64 delta) = 0;
  65
  66     virtual void IncrementDirtyCount(const GURL& origin,
  67                                     FileSystemType type) = 0;
  68     virtual void DecrementDirtyCount(const GURL& origin,
  69                                     FileSystemType type) = 0;
  70
  71    private:
  72     DISALLOW_COPY_AND_ASSIGN(QuotaBackend);
  73   };
  74
  75   explicit QuotaReservationManager(scoped_ptr<QuotaBackend> backend);
  76   ~QuotaReservationManager();
  77
  78   // The entry point of the quota reservation.  Creates new reservation object
  79   // for |origin| and |type|.
  80   scoped_refptr<QuotaReservation> CreateReservation(
  81       const GURL& origin,
  82       FileSystemType type);
  83
  84  private:
  85   typedef std::map<std::pair<GURL, FileSystemType>, QuotaReservationBuffer*>
  86       ReservationBufferByOriginAndType;
  87
  88   friend class QuotaReservation;
  89   friend class QuotaReservationBuffer;
  90   friend class content::QuotaReservationManagerTest;
  91
  92   void ReserveQuota(const GURL& origin,
  93                     FileSystemType type,
  94                     int64 delta,
  95                     const ReserveQuotaCallback& callback);
  96
  97   void ReleaseReservedQuota(const GURL& origin,
  98                             FileSystemType type,
  99                             int64 size);
 100
 101   void CommitQuotaUsage(const GURL& origin,
 102                         FileSystemType type,
 103                         int64 delta);
 104
 105   void IncrementDirtyCount(const GURL& origin, FileSystemType type);
 106   void DecrementDirtyCount(const GURL& origin, FileSystemType type);
 107
 108   scoped_refptr<QuotaReservationBuffer> GetReservationBuffer(
 109       const GURL& origin,
 110       FileSystemType type);
 111   void ReleaseReservationBuffer(QuotaReservationBuffer* reservation_pool);
 112
 113   scoped_ptr<QuotaBackend> backend_;
 114
 115   // Not owned.  The destructor of ReservationBuffer should erase itself from
 116   // |reservation_buffers_| by calling ReleaseReservationBuffer.
 117   ReservationBufferByOriginAndType reservation_buffers_;
 118
 119   base::SequenceChecker sequence_checker_;
 120   base::WeakPtrFactory<QuotaReservationManager> weak_ptr_factory_;
 121
 122   DISALLOW_COPY_AND_ASSIGN(QuotaReservationManager);
 123 };
 124
 125 }  // namespace storage
 126
 127 #endif  // STORAGE_BROWSER_FILEAPI_QUOTA_QUOTA_RESERVATION_MANAGER_H_