content/browser/renderer_host/pepper/quota_reservation.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 CONTENT_BROWSER_RENDERER_HOST_PEPPER_QUOTA_RESERVATION_H_
   6 #define CONTENT_BROWSER_RENDERER_HOST_PEPPER_QUOTA_RESERVATION_H_
   7
   8 #include <map>
   9
  10 #include "base/basictypes.h"
  11 #include "base/callback.h"
  12 #include "base/platform_file.h"
  13 #include "content/common/content_export.h"
  14 #include "ppapi/c/pp_stdint.h"  // For int64_t on Windows.
  15 #include "url/gurl.h"
  16 #include "webkit/browser/fileapi/file_system_context.h"
  17
  18 namespace base {
  19 class FilePath;
  20 }
  21
  22 namespace fileapi {
  23 class OpenFileHandle;
  24 class QuotaReservation;
  25 }
  26
  27 namespace content {
  28
  29 struct QuotaReservationDeleter;
  30
  31 // This class holds a QuotaReservation and manages OpenFileHandles for checking
  32 // quota. It should be created, used, and destroyed on a FileSystemContext's
  33 // default_file_task_runner() instance. This is a RefCountedThreadSafe object
  34 // because it needs to be passed to the file thread and kept alive during
  35 // potentially long-running quota operations.
  36 class CONTENT_EXPORT QuotaReservation
  37     : public base::RefCountedThreadSafe<QuotaReservation,
  38                                         QuotaReservationDeleter> {
  39  public:
  40   // Static method to facilitate construction on the file task runner.
  41   static scoped_refptr<QuotaReservation> Create(
  42       scoped_refptr<fileapi::FileSystemContext> file_system_context,
  43       const GURL& origin_url,
  44       fileapi::FileSystemType file_system_type);
  45
  46   // Opens a file with the given id and path and returns its current size.
  47   int64_t OpenFile(int32_t id, const base::FilePath& file_path);
  48   // Closes the file opened by OpenFile with the given id.
  49   void CloseFile(int32_t id, int64_t max_written_offset);
  50   // Refreshes the quota reservation to a new amount. A map that associates file
  51   // ids with maximum written offsets is provided as input. The callback will
  52   // receive a similar map with the updated file sizes.
  53   typedef std::map<int32_t, int64_t> OffsetMap;
  54   typedef base::Callback<void(int64_t, const OffsetMap&)> ReserveQuotaCallback;
  55   void ReserveQuota(int64_t amount,
  56                     const OffsetMap& max_written_offsets,
  57                     const ReserveQuotaCallback& callback);
  58
  59   // Notifies underlying QuotaReservation that the associated client crashed,
  60   // and that the reserved quota is no longer traceable.
  61   void OnClientCrash();
  62
  63  private:
  64   friend class base::RefCountedThreadSafe<QuotaReservation,
  65                                           QuotaReservationDeleter>;
  66   friend class base::DeleteHelper<QuotaReservation>;
  67   friend struct QuotaReservationDeleter;
  68   friend class QuotaReservationTest;
  69
  70   QuotaReservation(
  71       scoped_refptr<fileapi::FileSystemContext> file_system_context,
  72       const GURL& origin_url,
  73       fileapi::FileSystemType file_system_type);
  74
  75   // For unit testing only. A QuotaReservation intended for unit testing will
  76   // have file_system_context_ == NULL.
  77   QuotaReservation(
  78       scoped_refptr<fileapi::QuotaReservation> quota_reservation,
  79       const GURL& origin_url,
  80       fileapi::FileSystemType file_system_type);
  81
  82   ~QuotaReservation();
  83
  84   void GotReservedQuota(const ReserveQuotaCallback& callback,
  85                         base::PlatformFileError error);
  86
  87   void DeleteOnCorrectThread() const;
  88
  89   scoped_refptr<fileapi::FileSystemContext> file_system_context_;
  90   scoped_refptr<fileapi::QuotaReservation> quota_reservation_;
  91   typedef std::map<int32_t, fileapi::OpenFileHandle*> FileMap;
  92   FileMap files_;
  93
  94   DISALLOW_COPY_AND_ASSIGN(QuotaReservation);
  95 };
  96
  97 struct QuotaReservationDeleter {
  98   static void Destruct(const QuotaReservation* quota_reservation) {
  99     quota_reservation->DeleteOnCorrectThread();
 100   }
 101 };
 102
 103 }  // namespace content
 104
 105 #endif  // CONTENT_BROWSER_RENDERER_HOST_PEPPER_QUOTA_RESERVATION_H_