chrome/browser/media_galleries/fileapi/mtp_device_map_service.h

   1 // Copyright (c) 2012 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 CHROME_BROWSER_MEDIA_GALLERIES_FILEAPI_MTP_DEVICE_MAP_SERVICE_H_
   6 #define CHROME_BROWSER_MEDIA_GALLERIES_FILEAPI_MTP_DEVICE_MAP_SERVICE_H_
   7
   8 #include <map>
   9
  10 #include "base/files/file_path.h"
  11 #include "base/lazy_instance.h"
  12 #include "base/threading/thread_checker.h"
  13
  14 class MTPDeviceAsyncDelegate;
  15
  16 // This class provides media transfer protocol (MTP) device delegate to
  17 // complete media file system operations.
  18 // Lives on the IO thread in production.
  19 // TODO(gbillock): Make this class owned by the MediaFileSystemRegistry.
  20 class MTPDeviceMapService {
  21  public:
  22   static MTPDeviceMapService* GetInstance();
  23
  24   // Gets the media device delegate associated with |filesystem_id|.
  25   // Return NULL if the |filesystem_id| is no longer valid (e.g. because the
  26   // corresponding device is detached, etc).
  27   // Called on the IO thread.
  28   MTPDeviceAsyncDelegate* GetMTPDeviceAsyncDelegate(
  29       const std::string& filesystem_id);
  30
  31   // Register that an MTP filesystem is in use for the given |device_location|.
  32   void RegisterMTPFileSystem(
  33     const base::FilePath::StringType& device_location,
  34     const std::string& fsid);
  35
  36   // Removes the MTP entry associated with the given
  37   // |device_location|. Signals the MTPDeviceMapService to destroy the
  38   // delegate if there are no more uses of it.
  39   void RevokeMTPFileSystem(const std::string& fsid);
  40
  41  private:
  42   friend struct base::DefaultLazyInstanceTraits<MTPDeviceMapService>;
  43
  44   // Adds the MTP device delegate to the map service. |device_location|
  45   // specifies the mount location of the MTP device.
  46   // Called on the IO thread.
  47   void AddAsyncDelegate(const base::FilePath::StringType& device_location,
  48                         MTPDeviceAsyncDelegate* delegate);
  49
  50   // Removes the MTP device delegate from the map service. |device_location|
  51   // specifies the mount location of the MTP device.
  52   // Called on the IO thread.
  53   void RemoveAsyncDelegate(const base::FilePath::StringType& device_location);
  54
  55   // Mapping of device_location and MTPDeviceAsyncDelegate* object. It is safe
  56   // to store and access the raw pointer. This class operates on the IO thread.
  57   typedef std::map<base::FilePath::StringType, MTPDeviceAsyncDelegate*>
  58       AsyncDelegateMap;
  59
  60   // Map a filesystem id (fsid) to an MTP device location.
  61   typedef std::map<std::string, base::FilePath::StringType>
  62       MTPDeviceFileSystemMap;
  63
  64   // Map a MTP or PTP device location to a count of current uses of that
  65   // location.
  66   typedef std::map<const base::FilePath::StringType, int>
  67       MTPDeviceUsageMap;
  68
  69
  70   // Get access to this class using GetInstance() method.
  71   MTPDeviceMapService();
  72   ~MTPDeviceMapService();
  73
  74   // Map of attached mtp device async delegates.
  75   AsyncDelegateMap async_delegate_map_;
  76
  77   MTPDeviceFileSystemMap mtp_device_map_;
  78
  79   MTPDeviceUsageMap mtp_device_usage_map_;
  80
  81   DISALLOW_COPY_AND_ASSIGN(MTPDeviceMapService);
  82 };
  83
  84 #endif  // CHROME_BROWSER_MEDIA_GALLERIES_FILEAPI_MTP_DEVICE_MAP_SERVICE_H_