chrome/browser/media_galleries/linux/mtp_device_task_helper.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 CHROME_BROWSER_MEDIA_GALLERIES_LINUX_MTP_DEVICE_TASK_HELPER_H_
   6 #define CHROME_BROWSER_MEDIA_GALLERIES_LINUX_MTP_DEVICE_TASK_HELPER_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/callback.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "base/platform_file.h"
  15 #include "chrome/browser/media_galleries/fileapi/mtp_device_async_delegate.h"
  16 #include "device/media_transfer_protocol/mtp_file_entry.pb.h"
  17 #include "webkit/browser/fileapi/async_file_util.h"
  18
  19 class MTPReadFileWorker;
  20 struct SnapshotRequestInfo;
  21
  22 // MTPDeviceTaskHelper dispatches the media transfer protocol (MTP) device
  23 // operation requests (such as GetFileInfo, ReadDirectory, CreateSnapshotFile,
  24 // OpenStorage and CloseStorage) to the MediaTransferProtocolManager.
  25 // MTPDeviceTaskHelper lives on the UI thread. MTPDeviceTaskHelperMapService
  26 // owns the MTPDeviceTaskHelper objects. MTPDeviceTaskHelper is instantiated per
  27 // MTP device storage.
  28 class MTPDeviceTaskHelper {
  29  public:
  30   typedef base::Callback<void(bool succeeded)> OpenStorageCallback;
  31
  32   typedef MTPDeviceAsyncDelegate::GetFileInfoSuccessCallback
  33       GetFileInfoSuccessCallback;
  34
  35   typedef base::Callback<void(const fileapi::AsyncFileUtil::EntryList&)>
  36       ReadDirectorySuccessCallback;
  37
  38   typedef MTPDeviceAsyncDelegate::ErrorCallback ErrorCallback;
  39
  40   MTPDeviceTaskHelper();
  41   ~MTPDeviceTaskHelper();
  42
  43   // Dispatches the request to the MediaTransferProtocolManager to open the MTP
  44   // storage for communication.
  45   //
  46   // |storage_name| specifies the name of the storage device.
  47   // |callback| is called when the OpenStorage request completes. |callback|
  48   // runs on the IO thread.
  49   void OpenStorage(const std::string& storage_name,
  50                    const OpenStorageCallback& callback);
  51
  52   // Dispatches the GetFileInfoByPath request to the
  53   // MediaTransferProtocolManager.
  54   //
  55   // |file_path| specifies the relative of the file whose details are requested.
  56   //
  57   // If the file details are fetched successfully, |success_callback| is invoked
  58   // on the IO thread to notify the caller about the file details.
  59   //
  60   // If there is an error, |error_callback| is invoked on the IO thread to
  61   // notify the caller about the file error.
  62   void GetFileInfoByPath(
  63       const std::string& file_path,
  64       const GetFileInfoSuccessCallback& success_callback,
  65       const ErrorCallback& error_callback);
  66
  67   // Dispatches the read directory request to the MediaTransferProtocolManager.
  68   //
  69   // |dir_path| specifies the directory file path.
  70   //
  71   // If the directory file entries are enumerated successfully,
  72   // |success_callback| is invoked on the IO thread to notify the caller about
  73   // the directory file entries.
  74   //
  75   // If there is an error, |error_callback| is invoked on the IO thread to
  76   // notify the caller about the file error.
  77   void ReadDirectoryByPath(const std::string& dir_path,
  78                            const ReadDirectorySuccessCallback& success_callback,
  79                            const ErrorCallback& error_callback);
  80
  81   // Forwards the WriteDataIntoSnapshotFile request to the MTPReadFileWorker
  82   // object.
  83   //
  84   // |request_info| specifies the snapshot file request params.
  85   // |snapshot_file_info| specifies the metadata of the snapshot file.
  86   void WriteDataIntoSnapshotFile(
  87       const SnapshotRequestInfo& request_info,
  88       const base::File::Info& snapshot_file_info);
  89
  90   // Dispatches the read bytes request to the MediaTransferProtocolManager.
  91   //
  92   // |request| contains details about the byte request including the file path,
  93   // byte range, and the callbacks. The callbacks specified within |request| are
  94   // called on the IO thread to notify the caller about success or failure.
  95   void ReadBytes(const MTPDeviceAsyncDelegate::ReadBytesRequest& request);
  96
  97   // Dispatches the CloseStorage request to the MediaTransferProtocolManager.
  98   void CloseStorage() const;
  99
 100  private:
 101   // Query callback for OpenStorage() to run |callback| on the IO thread.
 102   //
 103   // If OpenStorage request succeeds, |error| is set to false and
 104   // |device_handle| contains the handle to communicate with the MTP device.
 105   //
 106   // If OpenStorage request fails, |error| is set to true and |device_handle| is
 107   // set to an empty string.
 108   void OnDidOpenStorage(const OpenStorageCallback& callback,
 109                         const std::string& device_handle,
 110                         bool error);
 111
 112   // Query callback for GetFileInfo().
 113   //
 114   // If there is no error, |file_entry| will contain the
 115   // requested media device file details and |error| is set to false.
 116   // |success_callback| is invoked on the IO thread to notify the caller.
 117   //
 118   // If there is an error, |file_entry| is invalid and |error| is
 119   // set to true. |error_callback| is invoked on the IO thread to notify the
 120   // caller.
 121   void OnGetFileInfo(const GetFileInfoSuccessCallback& success_callback,
 122                      const ErrorCallback& error_callback,
 123                      const MtpFileEntry& file_entry,
 124                      bool error) const;
 125
 126   // Query callback for ReadDirectoryByPath().
 127   //
 128   // If there is no error, |error| is set to false, |file_entries| has the
 129   // directory file entries and |success_callback| is invoked on the IO thread
 130   // to notify the caller.
 131   //
 132   // If there is an error, |error| is set to true, |file_entries| is empty
 133   // and |error_callback| is invoked on the IO thread to notify the caller.
 134   void OnDidReadDirectoryByPath(
 135       const ReadDirectorySuccessCallback& success_callback,
 136       const ErrorCallback& error_callback,
 137       const std::vector<MtpFileEntry>& file_entries,
 138       bool error) const;
 139
 140   // Query callback for ReadBytes();
 141   //
 142   // If there is no error, |error| is set to false, the buffer within |request|
 143   // is written to, and the success callback within |request| is invoked on the
 144   // IO thread to notify the caller.
 145   //
 146   // If there is an error, |error| is set to true, the buffer within |request|
 147   // is untouched, and the error callback within |request| is invoked on the
 148   // IO thread to notify the caller.
 149   void OnDidReadBytes(
 150       const MTPDeviceAsyncDelegate::ReadBytesRequest& request,
 151       const std::string& data,
 152       bool error) const;
 153
 154   // Called when the device is uninitialized.
 155   //
 156   // Runs |error_callback| on the IO thread to notify the caller about the
 157   // device |error|.
 158   void HandleDeviceError(const ErrorCallback& error_callback,
 159                          base::File::Error error) const;
 160
 161   // Handle to communicate with the MTP device.
 162   std::string device_handle_;
 163
 164   // Used to handle WriteDataInfoSnapshotFile request.
 165   scoped_ptr<MTPReadFileWorker> read_file_worker_;
 166
 167   // For callbacks that may run after destruction.
 168   base::WeakPtrFactory<MTPDeviceTaskHelper> weak_ptr_factory_;
 169
 170   DISALLOW_COPY_AND_ASSIGN(MTPDeviceTaskHelper);
 171 };
 172
 173 #endif  // CHROME_BROWSER_MEDIA_GALLERIES_LINUX_MTP_DEVICE_TASK_HELPER_H_