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