// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CHROME_BROWSER_MEDIA_GALLERIES_WIN_MTP_DEVICE_DELEGATE_IMPL_WIN_H_
#define CHROME_BROWSER_MEDIA_GALLERIES_WIN_MTP_DEVICE_DELEGATE_IMPL_WIN_H_
#include <queue>
#include "base/callback.h"
#include "base/files/file.h"
#include "base/location.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/strings/string16.h"
#include "base/win/scoped_comptr.h"
#include "chrome/browser/media_galleries/fileapi/mtp_device_async_delegate.h"
#include "webkit/browser/fileapi/async_file_util.h"
namespace base {
class FilePath;
class SequencedTaskRunner;
}
class SnapshotFileDetails;
struct SnapshotRequestInfo;
// MTPDeviceDelegateImplWin is used to communicate with the media transfer
// protocol (MTP) device to complete file system operations. These operations
// are performed asynchronously on a blocking pool thread since the device
// access may be slow and may take a long time to complete. MTP
// device can have multiple data storage partitions. MTPDeviceDelegateImplWin
// is instantiated per MTP device storage partition using
// CreateMTPDeviceAsyncDelegate(). MTPDeviceDelegateImplWin lives on the IO
// thread.
class MTPDeviceDelegateImplWin : public MTPDeviceAsyncDelegate {
public:
// Structure used to represent MTP device storage partition details.
struct StorageDeviceInfo {
StorageDeviceInfo(const base::string16& pnp_device_id,
const base::string16& registered_device_path,
const base::string16& storage_object_id);
// The PnP Device Id, used to open the device for communication,
// e.g. "\\?\usb#vid_04a9&pid_3073#12#{6ac27878-a6fa-4155-ba85-f1d4f33}".
const base::string16 pnp_device_id;
// The media file system root path, which is obtained during the
// registration of MTP device storage partition as a file system,
// e.g. "\\MTP:StorageSerial:SID-{10001,E,9823}:237483".
const base::string16 registered_device_path;
// The MTP device storage partition object identifier, used to enumerate the
// storage contents, e.g. "s10001".
const base::string16 storage_object_id;
};
private:
friend void OnGetStorageInfoCreateDelegate(
const base::string16& device_location,
const CreateMTPDeviceAsyncDelegateCallback& callback,
base::string16* pnp_device_id,
base::string16* storage_object_id,
bool succeeded);
enum InitializationState {
UNINITIALIZED = 0,
PENDING_INIT,
INITIALIZED
};
// Used to represent pending task details.
struct PendingTaskInfo {
PendingTaskInfo(const tracked_objects::Location& location,
const base::Callback<base::File::Error(void)>& task,
const base::Callback<void(base::File::Error)>& reply);
const tracked_objects::Location location;
const base::Callback<base::File::Error(void)> task;
const base::Callback<void(base::File::Error)> reply;
};
// Defers the device initializations until the first file operation request.
// Do all the initializations in EnsureInitAndRunTask() function.
MTPDeviceDelegateImplWin(const base::string16& registered_device_path,
const base::string16& pnp_device_id,
const base::string16& storage_object_id);
// Destructed via CancelPendingTasksAndDeleteDelegate().
virtual ~MTPDeviceDelegateImplWin();
// MTPDeviceAsyncDelegate:
virtual void GetFileInfo(
const base::FilePath& file_path,
const GetFileInfoSuccessCallback& success_callback,
const ErrorCallback& error_callback) OVERRIDE;
virtual void ReadDirectory(
const base::FilePath& root,
const ReadDirectorySuccessCallback& success_callback,
const ErrorCallback& error_callback) OVERRIDE;
virtual void CreateSnapshotFile(
const base::FilePath& device_file_path,
const base::FilePath& local_path,
const CreateSnapshotFileSuccessCallback& success_callback,
const ErrorCallback& error_callback) OVERRIDE;
virtual bool IsStreaming() OVERRIDE;
virtual void ReadBytes(
const base::FilePath& device_file_path,
net::IOBuffer* buf, int64 offset, int buf_len,
const ReadBytesSuccessCallback& success_callback,
const ErrorCallback& error_callback) OVERRIDE;
virtual void CancelPendingTasksAndDeleteDelegate() OVERRIDE;
// Ensures the device is initialized for communication by doing a
// call-and-reply to a blocking pool thread. |task_info.task| runs on a
// blocking pool thread and |task_info.reply| runs on the IO thread.
//
// If the device is already initialized, post the |task_info.task|
// immediately on a blocking pool thread.
//
// If the device is uninitialized, store the |task_info| in a pending task
// list and then runs all the pending tasks once the device is successfully
// initialized.
void EnsureInitAndRunTask(const PendingTaskInfo& task_info);
// Writes data chunk from the device to the snapshot file path based on the
// parameters in |current_snapshot_details_| by doing a call-and-reply to a
// blocking pool thread.
void WriteDataChunkIntoSnapshotFile();
// Processes the next pending request.
void ProcessNextPendingRequest();
// Handles the event that the device is initialized. |succeeded| indicates
// whether device initialization succeeded or not. If the device is
// successfully initialized, runs the next pending task.
void OnInitCompleted(bool succeeded);
// Called when GetFileInfo() completes. |file_info| specifies the requested
// file details. |error| specifies the platform file error code.
//
// If the GetFileInfo() succeeds, |success_callback| is invoked to notify the
// caller about the |file_info| details.
//
// If the GetFileInfo() fails, |file_info| is not set and |error_callback| is
// invoked to notify the caller about the platform file |error|.
void OnGetFileInfo(const GetFileInfoSuccessCallback& success_callback,
const ErrorCallback& error_callback,
base::File::Info* file_info,
base::File::Error error);
// Called when ReadDirectory() completes. |file_list| contains the directory
// file entries information. |error| specifies the platform file error code.
//
// If the ReadDirectory() succeeds, |success_callback| is invoked to notify
// the caller about the directory file entries.
//
// If the ReadDirectory() fails, |file_list| is not set and |error_callback|
// is invoked to notify the caller about the platform file |error|.
void OnDidReadDirectory(const ReadDirectorySuccessCallback& success_callback,
const ErrorCallback& error_callback,
fileapi::AsyncFileUtil::EntryList* file_list,
base::File::Error error);
// Called when the get file stream request completes.
// |file_details.request_info| contains the CreateSnapshot request param
// details. |error| specifies the platform file error code.
//
// If the file stream of the device file is successfully
// fetched, |file_details| will contain the required details for the creation
// of the snapshot file.
//
// If the get file stream request fails, |error| is set accordingly.
void OnGetFileStream(scoped_ptr<SnapshotFileDetails> file_details,
base::File::Error error);
// Called when WriteDataChunkIntoSnapshotFile() completes.
// |bytes_written| specifies the number of bytes written into the
// |snapshot_file_path| during the last write operation.
//
// If the write operation succeeds, |bytes_written| is set to a non-zero
// value.
//
// If the write operation fails, |bytes_written| is set to zero.
void OnWroteDataChunkIntoSnapshotFile(
const base::FilePath& snapshot_file_path,
DWORD bytes_written);
// Portable device initialization state.
InitializationState init_state_;
// The task runner where the device operation tasks runs.
scoped_refptr<base::SequencedTaskRunner> media_task_runner_;
// Device storage partition details
// (e.g. device path, PnP device id and storage object id).
StorageDeviceInfo storage_device_info_;
// Used to track the current state of the snapshot file (e.g how many bytes
// written to the snapshot file, optimal data transfer size, source file
// stream, etc).
//
// A snapshot file is created incrementally. CreateSnapshotFile request reads
// and writes the snapshot file data in chunks. In order to retain the order
// of the snapshot file requests, make sure there is only one active snapshot
// file request at any time.
scoped_ptr<SnapshotFileDetails> current_snapshot_details_;
// A list of pending tasks that needs to be run when the device is
// initialized or when the current task in progress is complete.
std::queue<PendingTaskInfo> pending_tasks_;
// Used to make sure only one task is in progress at any time.
bool task_in_progress_;
// For callbacks that may run after destruction.
base::WeakPtrFactory<MTPDeviceDelegateImplWin> weak_ptr_factory_;
DISALLOW_COPY_AND_ASSIGN(MTPDeviceDelegateImplWin);
};
#endif // CHROME_BROWSER_MEDIA_GALLERIES_WIN_MTP_DEVICE_DELEGATE_IMPL_WIN_H_