Isolated FS for media devices.

webkit/fileapi/media/mtp_device_interface_impl_linux.h

+// Copyright (c) 2012 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 WEBKIT_FILEAPI_MEDIA_MTP_DEVICE_INTERFACE_IMPL_LINUX_H_
+#define WEBKIT_FILEAPI_MEDIA_MTP_DEVICE_INTERFACE_IMPL_LINUX_H_
+
+#include "base/file_path.h"
+#include "base/memory/ref_counted.h"
+#include "base/platform_file.h"
+#include "base/sequenced_task_runner_helpers.h"
+#include "base/timer.h"
+#include "webkit/fileapi/file_system_file_util.h"
+#include "webkit/fileapi/media/media_device_interface.h"
+
+namespace base {
+struct PlatformFileInfo;
+class SequencedTaskRunner;
+class Time;
+}
+
+namespace fileapi {
+
+using base::PlatformFileError;
+using base::PlatformFileInfo;
+using base::RefCountedThreadSafe;
+using base::Time;
+using base::SequencedTaskRunner;

[kinuko, 2012/07/31 05:35:44]

nit: Some other fileapi header file does the same but in general I think using
'using' in .h file is discouraged unless they are in functions or classes.

http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml#Namespaces
"You may use a using-declaration anywhere in a .cc file, and in functions,
methods or classes in .h files."

[kmadhusu, 2012/07/31 19:47:24]

sure. Done.

+
+struct DefaultMtpDeviceInterfaceImplDeleter;
+
+// Helper class to support MTP device isolated file system operations. This
+// class contains platform specific code to communicate with the attached
+// MTP device. We instantiate this class per MTP device. MTP device is
+// opened for communication during initialization and closed during
+// destruction.
+class MtpDeviceInterfaceImplLinux :
+    public MediaDeviceInterface,
+    public RefCountedThreadSafe<MtpDeviceInterfaceImplLinux,
+                                DefaultMtpDeviceInterfaceImplDeleter> {
+ public:
+  MtpDeviceInterfaceImplLinux(const FilePath::StringType& device_id,
+                              SequencedTaskRunner* media_task_runner) OVERRIDE;
+
+  // MediaDeviceInterface methods.
+  virtual PlatformFileError GetFileInfo(const FilePath& file_path,
+                                        PlatformFileInfo* file_info) OVERRIDE;
+
+  virtual FileSystemFileUtil::AbstractFileEnumerator* CreateFileEnumerator(
+      const FilePath& root,
+      bool recursive) OVERRIDE;
+
+  virtual PlatformFileError Touch(const FilePath& file_path,
+                                  const Time& last_access_time,
+                                  const Time& last_modified_time) OVERRIDE;
+
+  virtual bool PathExists(const FilePath& file_path) OVERRIDE;
+  virtual bool DirectoryExists(const FilePath& file_path) OVERRIDE;
+  virtual bool IsDirectoryEmpty(const FilePath& file_path) OVERRIDE;
+  virtual PlatformFileError CreateSnapshotFile(
+      const FilePath& device_file_path,
+      const FilePath& local_path,
+      PlatformFileInfo* file_info) OVERRIDE;
+
+ private:
+  friend struct DefaultMtpDeviceInterfaceImplDeleter;
+  friend class base::DeleteHelper<MtpDeviceInterfaceImplLinux>;
+  friend class RefCountedThreadSafe<MtpDeviceInterfaceImplLinux,
+                                    DefaultMtpDeviceInterfaceImplDeleter>;
+
+  virtual ~MtpDeviceInterfaceImplLinux();
+  void DeleteOnCorrectThread() const;
+
+  // Device initialization should be done in |media_task_runner_|.
+  bool LazyInit();
+
+  // Mtp device id.
+  FilePath::StringType device_id_;
+  scoped_refptr<SequencedTaskRunner> media_task_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(MtpDeviceInterfaceImplLinux);
+};
+
+struct DefaultMtpDeviceInterfaceImplDeleter {
+  static void Destruct(const MtpDeviceInterfaceImplLinux* device_impl) {
+    device_impl->DeleteOnCorrectThread();
+  }
+};
+
+}  // namespace fileapi
+
+#endif  // WEBKIT_FILEAPI_MEDIA_MTP_DEVICE_INTERFACE_IMPL_LINUX_H_