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/files/file.h"
  12 #include "base/location.h"
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/memory/weak_ptr.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::File::Error(void)>& task,
  76                     const base::Callback<void(base::File::Error)>& reply);
  77
  78     const tracked_objects::Location location;
  79     const base::Callback<base::File::Error(void)> task;
  80     const base::Callback<void(base::File::Error)> 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 bool IsStreaming() OVERRIDE;
 107   virtual void ReadBytes(
 108       const base::FilePath& device_file_path,
 109       net::IOBuffer* buf, int64 offset, int buf_len,
 110       const ReadBytesSuccessCallback& success_callback,
 111       const ErrorCallback& error_callback) OVERRIDE;
 112   virtual void CancelPendingTasksAndDeleteDelegate() OVERRIDE;
 113
 114   // Ensures the device is initialized for communication by doing a
 115   // call-and-reply to a blocking pool thread. |task_info.task| runs on a
 116   // blocking pool thread and |task_info.reply| runs on the IO thread.
 117   //
 118   // If the device is already initialized, post the |task_info.task|
 119   // immediately on a blocking pool thread.
 120   //
 121   // If the device is uninitialized, store the |task_info| in a pending task
 122   // list and then runs all the pending tasks once the device is successfully
 123   // initialized.
 124   void EnsureInitAndRunTask(const PendingTaskInfo& task_info);
 125
 126   // Writes data chunk from the device to the snapshot file path based on the
 127   // parameters in |current_snapshot_details_| by doing a call-and-reply to a
 128   // blocking pool thread.
 129   void WriteDataChunkIntoSnapshotFile();
 130
 131   // Processes the next pending request.
 132   void ProcessNextPendingRequest();
 133
 134   // Handles the event that the device is initialized. |succeeded| indicates
 135   // whether device initialization succeeded or not. If the device is
 136   // successfully initialized, runs the next pending task.
 137   void OnInitCompleted(bool succeeded);
 138
 139   // Called when GetFileInfo() completes. |file_info| specifies the requested
 140   // file details. |error| specifies the platform file error code.
 141   //
 142   // If the GetFileInfo() succeeds, |success_callback| is invoked to notify the
 143   // caller about the |file_info| details.
 144   //
 145   // If the GetFileInfo() fails, |file_info| is not set and |error_callback| is
 146   // invoked to notify the caller about the platform file |error|.
 147   void OnGetFileInfo(const GetFileInfoSuccessCallback& success_callback,
 148                      const ErrorCallback& error_callback,
 149                      base::File::Info* file_info,
 150                      base::File::Error error);
 151
 152   // Called when ReadDirectory() completes. |file_list| contains the directory
 153   // file entries information. |error| specifies the platform file error code.
 154   //
 155   // If the ReadDirectory() succeeds, |success_callback| is invoked to notify
 156   // the caller about the directory file entries.
 157   //
 158   // If the ReadDirectory() fails, |file_list| is not set and |error_callback|
 159   // is invoked to notify the caller about the platform file |error|.
 160   void OnDidReadDirectory(const ReadDirectorySuccessCallback& success_callback,
 161                           const ErrorCallback& error_callback,
 162                           fileapi::AsyncFileUtil::EntryList* file_list,
 163                           base::File::Error error);
 164
 165   // Called when the get file stream request completes.
 166   // |file_details.request_info| contains the CreateSnapshot request param
 167   // details. |error| specifies the platform file error code.
 168   //
 169   // If the file stream of the device file is successfully
 170   // fetched, |file_details| will contain the required details for the creation
 171   // of the snapshot file.
 172   //
 173   // If the get file stream request fails, |error| is set accordingly.
 174   void OnGetFileStream(scoped_ptr<SnapshotFileDetails> file_details,
 175                        base::File::Error error);
 176
 177   // Called when WriteDataChunkIntoSnapshotFile() completes.
 178   // |bytes_written| specifies the number of bytes written into the
 179   // |snapshot_file_path| during the last write operation.
 180   //
 181   // If the write operation succeeds, |bytes_written| is set to a non-zero
 182   // value.
 183   //
 184   // If the write operation fails, |bytes_written| is set to zero.
 185   void OnWroteDataChunkIntoSnapshotFile(
 186       const base::FilePath& snapshot_file_path,
 187       DWORD bytes_written);
 188
 189   // Portable device initialization state.
 190   InitializationState init_state_;
 191
 192   // The task runner where the device operation tasks runs.
 193   scoped_refptr<base::SequencedTaskRunner> media_task_runner_;
 194
 195   // Device storage partition details
 196   // (e.g. device path, PnP device id and storage object id).
 197   StorageDeviceInfo storage_device_info_;
 198
 199   // Used to track the current state of the snapshot file (e.g how many bytes
 200   // written to the snapshot file, optimal data transfer size, source file
 201   // stream, etc).
 202   //
 203   // A snapshot file is created incrementally. CreateSnapshotFile request reads
 204   // and writes the snapshot file data in chunks. In order to retain the order
 205   // of the snapshot file requests, make sure there is only one active snapshot
 206   // file request at any time.
 207   scoped_ptr<SnapshotFileDetails> current_snapshot_details_;
 208
 209   // A list of pending tasks that needs to be run when the device is
 210   // initialized or when the current task in progress is complete.
 211   std::queue<PendingTaskInfo> pending_tasks_;
 212
 213   // Used to make sure only one task is in progress at any time.
 214   bool task_in_progress_;
 215
 216   // For callbacks that may run after destruction.
 217   base::WeakPtrFactory<MTPDeviceDelegateImplWin> weak_ptr_factory_;
 218
 219   DISALLOW_COPY_AND_ASSIGN(MTPDeviceDelegateImplWin);
 220 };
 221
 222 #endif  // CHROME_BROWSER_MEDIA_GALLERIES_WIN_MTP_DEVICE_DELEGATE_IMPL_WIN_H_