chrome/browser/media_galleries/win/mtp_device_delegate_impl_win.h

   1 // Copyright (c) 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 CHROME_BROWSER_MEDIA_GALLERIES_WIN_MTP_DEVICE_DELEGATE_IMPL_WIN_H_
   6 #define CHROME_BROWSER_MEDIA_GALLERIES_WIN_MTP_DEVICE_DELEGATE_IMPL_WIN_H_
   7
   8 #include <queue>
   9
  10 #include "base/callback.h"
  11 #include "base/location.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "base/platform_file.h"
  15 #include "base/strings/string16.h"
  16 #include "base/win/scoped_comptr.h"
  17 #include "chrome/browser/media_galleries/fileapi/mtp_device_async_delegate.h"
  18 #include "webkit/browser/fileapi/async_file_util.h"
  19
  20 namespace base {
  21 class FilePath;
  22 class SequencedTaskRunner;
  23 }
  24
  25 class SnapshotFileDetails;
  26 struct SnapshotRequestInfo;
  27
  28 // MTPDeviceDelegateImplWin is used to communicate with the media transfer
  29 // protocol (MTP) device to complete file system operations. These operations
  30 // are performed asynchronously on a blocking pool thread since the device
  31 // access may be slow and may take a long time to complete. MTP
  32 // device can have multiple data storage partitions. MTPDeviceDelegateImplWin
  33 // is instantiated per MTP device storage partition using
  34 // CreateMTPDeviceAsyncDelegate(). MTPDeviceDelegateImplWin lives on the IO
  35 // thread.
  36 class MTPDeviceDelegateImplWin : public MTPDeviceAsyncDelegate {
  37  public:
  38   // Structure used to represent MTP device storage partition details.
  39   struct StorageDeviceInfo {
  40     StorageDeviceInfo(const base::string16& pnp_device_id,
  41                       const base::string16& registered_device_path,
  42                       const base::string16& storage_object_id);
  43
  44     // The PnP Device Id, used to open the device for communication,
  45     // e.g. "\\?\usb#vid_04a9&pid_3073#12#{6ac27878-a6fa-4155-ba85-f1d4f33}".
  46     const base::string16 pnp_device_id;
  47
  48     // The media file system root path, which is obtained during the
  49     // registration of MTP device storage partition as a file system,
  50     // e.g. "\\MTP:StorageSerial:SID-{10001,E,9823}:237483".
  51     const base::string16 registered_device_path;
  52
  53     // The MTP device storage partition object identifier, used to enumerate the
  54     // storage contents, e.g. "s10001".
  55     const base::string16 storage_object_id;
  56   };
  57
  58  private:
  59   friend void OnGetStorageInfoCreateDelegate(
  60       const base::string16& device_location,
  61       const CreateMTPDeviceAsyncDelegateCallback& callback,
  62       base::string16* pnp_device_id,
  63       base::string16* storage_object_id,
  64       bool succeeded);
  65
  66   enum InitializationState {
  67     UNINITIALIZED = 0,
  68     PENDING_INIT,
  69     INITIALIZED
  70   };
  71
  72   // Used to represent pending task details.
  73   struct PendingTaskInfo {
  74     PendingTaskInfo(const tracked_objects::Location& location,
  75                     const base::Callback<base::PlatformFileError(void)>& task,
  76                     const base::Callback<void(base::PlatformFileError)>& reply);
  77
  78     const tracked_objects::Location location;
  79     const base::Callback<base::PlatformFileError(void)> task;
  80     const base::Callback<void(base::PlatformFileError)> reply;
  81   };
  82
  83   // Defers the device initializations until the first file operation request.
  84   // Do all the initializations in EnsureInitAndRunTask() function.
  85   MTPDeviceDelegateImplWin(const base::string16& registered_device_path,
  86                            const base::string16& pnp_device_id,
  87                            const base::string16& storage_object_id);
  88
  89   // Destructed via CancelPendingTasksAndDeleteDelegate().
  90   virtual ~MTPDeviceDelegateImplWin();
  91
  92   // MTPDeviceAsyncDelegate:
  93   virtual void GetFileInfo(
  94       const base::FilePath& file_path,
  95       const GetFileInfoSuccessCallback& success_callback,
  96       const ErrorCallback& error_callback) OVERRIDE;
  97   virtual void ReadDirectory(
  98       const base::FilePath& root,
  99       const ReadDirectorySuccessCallback& success_callback,
 100       const ErrorCallback& error_callback) OVERRIDE;
 101   virtual void CreateSnapshotFile(
 102       const base::FilePath& device_file_path,
 103       const base::FilePath& local_path,
 104       const CreateSnapshotFileSuccessCallback& success_callback,
 105       const ErrorCallback& error_callback) OVERRIDE;
 106   virtual void CancelPendingTasksAndDeleteDelegate() OVERRIDE;
 107
 108   // Ensures the device is initialized for communication by doing a
 109   // call-and-reply to a blocking pool thread. |task_info.task| runs on a
 110   // blocking pool thread and |task_info.reply| runs on the IO thread.
 111   //
 112   // If the device is already initialized, post the |task_info.task|
 113   // immediately on a blocking pool thread.
 114   //
 115   // If the device is uninitialized, store the |task_info| in a pending task
 116   // list and then runs all the pending tasks once the device is successfully
 117   // initialized.
 118   void EnsureInitAndRunTask(const PendingTaskInfo& task_info);
 119
 120   // Writes data chunk from the device to the snapshot file path based on the
 121   // parameters in |current_snapshot_details_| by doing a call-and-reply to a
 122   // blocking pool thread.
 123   void WriteDataChunkIntoSnapshotFile();
 124
 125   // Processes the next pending request.
 126   void ProcessNextPendingRequest();
 127
 128   // Handles the event that the device is initialized. |succeeded| indicates
 129   // whether device initialization succeeded or not. If the device is
 130   // successfully initialized, runs the next pending task.
 131   void OnInitCompleted(bool succeeded);
 132
 133   // Called when GetFileInfo() completes. |file_info| specifies the requested
 134   // file details. |error| specifies the platform file error code.
 135   //
 136   // If the GetFileInfo() succeeds, |success_callback| is invoked to notify the
 137   // caller about the |file_info| details.
 138   //
 139   // If the GetFileInfo() fails, |file_info| is not set and |error_callback| is
 140   // invoked to notify the caller about the platform file |error|.
 141   void OnGetFileInfo(const GetFileInfoSuccessCallback& success_callback,
 142                      const ErrorCallback& error_callback,
 143                      base::PlatformFileInfo* file_info,
 144                      base::PlatformFileError error);
 145
 146   // Called when ReadDirectory() completes. |file_list| contains the directory
 147   // file entries information. |error| specifies the platform file error code.
 148   //
 149   // If the ReadDirectory() succeeds, |success_callback| is invoked to notify
 150   // the caller about the directory file entries.
 151   //
 152   // If the ReadDirectory() fails, |file_list| is not set and |error_callback|
 153   // is invoked to notify the caller about the platform file |error|.
 154   void OnDidReadDirectory(const ReadDirectorySuccessCallback& success_callback,
 155                           const ErrorCallback& error_callback,
 156                           fileapi::AsyncFileUtil::EntryList* file_list,
 157                           base::PlatformFileError error);
 158
 159   // Called when the get file stream request completes.
 160   // |file_details.request_info| contains the CreateSnapshot request param
 161   // details. |error| specifies the platform file error code.
 162   //
 163   // If the file stream of the device file is successfully
 164   // fetched, |file_details| will contain the required details for the creation
 165   // of the snapshot file.
 166   //
 167   // If the get file stream request fails, |error| is set accordingly.
 168   void OnGetFileStream(scoped_ptr<SnapshotFileDetails> file_details,
 169                        base::PlatformFileError error);
 170
 171   // Called when WriteDataChunkIntoSnapshotFile() completes.
 172   // |bytes_written| specifies the number of bytes written into the
 173   // |snapshot_file_path| during the last write operation.
 174   //
 175   // If the write operation succeeds, |bytes_written| is set to a non-zero
 176   // value.
 177   //
 178   // If the write operation fails, |bytes_written| is set to zero.
 179   void OnWroteDataChunkIntoSnapshotFile(
 180       const base::FilePath& snapshot_file_path,
 181       DWORD bytes_written);
 182
 183   // Portable device initialization state.
 184   InitializationState init_state_;
 185
 186   // The task runner where the device operation tasks runs.
 187   scoped_refptr<base::SequencedTaskRunner> media_task_runner_;
 188
 189   // Device storage partition details
 190   // (e.g. device path, PnP device id and storage object id).
 191   StorageDeviceInfo storage_device_info_;
 192
 193   // Used to track the current state of the snapshot file (e.g how many bytes
 194   // written to the snapshot file, optimal data transfer size, source file
 195   // stream, etc).
 196   //
 197   // A snapshot file is created incrementally. CreateSnapshotFile request reads
 198   // and writes the snapshot file data in chunks. In order to retain the order
 199   // of the snapshot file requests, make sure there is only one active snapshot
 200   // file request at any time.
 201   scoped_ptr<SnapshotFileDetails> current_snapshot_details_;
 202
 203   // A list of pending tasks that needs to be run when the device is
 204   // initialized or when the current task in progress is complete.
 205   std::queue<PendingTaskInfo> pending_tasks_;
 206
 207   // Used to make sure only one task is in progress at any time.
 208   bool task_in_progress_;
 209
 210   // For callbacks that may run after destruction.
 211   base::WeakPtrFactory<MTPDeviceDelegateImplWin> weak_ptr_factory_;
 212
 213   DISALLOW_COPY_AND_ASSIGN(MTPDeviceDelegateImplWin);
 214 };
 215
 216 #endif  // CHROME_BROWSER_MEDIA_GALLERIES_WIN_MTP_DEVICE_DELEGATE_IMPL_WIN_H_