Make NativeMediaFileUtil an AsyncFileUtil

chrome/browser/media_galleries/fileapi/native_media_file_util.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 CHROME_BROWSER_MEDIA_GALLERIES_FILEAPI_NATIVE_MEDIA_FILE_UTIL_H_
 #define CHROME_BROWSER_MEDIA_GALLERIES_FILEAPI_NATIVE_MEDIA_FILE_UTIL_H_
 
 #include "base/memory/scoped_ptr.h"
-#include "webkit/browser/fileapi/isolated_file_util.h"
+#include "base/memory/weak_ptr.h"
+#include "webkit/browser/fileapi/async_file_util.h"
 
 namespace chrome {
 
-// This class handles native file system operations with media type filtering
-// which is passed to each method via fileapi::FileSystemOperationContext as
-// MediaPathFilter.
-class NativeMediaFileUtil : public fileapi::IsolatedFileUtil {
+// This class handles native file system operations with media type filtering.
+// To support virtual file systems it implements the AsyncFileUtil interface
+// from scratch and provides synchronous override points.
+class NativeMediaFileUtil : public fileapi::AsyncFileUtil {
  public:
   NativeMediaFileUtil();
+  virtual ~NativeMediaFileUtil();
 
-  virtual base::PlatformFileError CreateOrOpen(
+  // AsyncFileUtil overrides.
+  virtual bool CreateOrOpen(
       fileapi::FileSystemOperationContext* context,
       const fileapi::FileSystemURL& url,
       int file_flags,
-      base::PlatformFile* file_handle,
-      bool* created) OVERRIDE;
-  virtual base::PlatformFileError EnsureFileExists(
+      const CreateOrOpenCallback& callback) OVERRIDE;
+  virtual bool EnsureFileExists(
       fileapi::FileSystemOperationContext* context,
-      const fileapi::FileSystemURL& url, bool* created) OVERRIDE;
-  virtual scoped_ptr<AbstractFileEnumerator> CreateFileEnumerator(
+      const fileapi::FileSystemURL& url,
+      const EnsureFileExistsCallback& callback) OVERRIDE;
+  virtual bool CreateDirectory(
       fileapi::FileSystemOperationContext* context,
-      const fileapi::FileSystemURL& root_url) OVERRIDE;
-  virtual base::PlatformFileError Touch(
+      const fileapi::FileSystemURL& url,
+      bool exclusive,
+      bool recursive,
+      const StatusCallback& callback) OVERRIDE;
+  virtual bool GetFileInfo(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      const GetFileInfoCallback& callback) OVERRIDE;
+  virtual bool ReadDirectory(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      const ReadDirectoryCallback& callback) OVERRIDE;
+  virtual bool Touch(
       fileapi::FileSystemOperationContext* context,
       const fileapi::FileSystemURL& url,
       const base::Time& last_access_time,
-      const base::Time& last_modified_time) OVERRIDE;
-  virtual base::PlatformFileError Truncate(
+      const base::Time& last_modified_time,
+      const StatusCallback& callback) OVERRIDE;
+  virtual bool Truncate(
       fileapi::FileSystemOperationContext* context,
       const fileapi::FileSystemURL& url,
-      int64 length) OVERRIDE;
-  virtual base::PlatformFileError CopyOrMoveFile(
+      int64 length,
+      const StatusCallback& callback) OVERRIDE;
+  virtual bool CopyFileLocal(
       fileapi::FileSystemOperationContext* context,
       const fileapi::FileSystemURL& src_url,
       const fileapi::FileSystemURL& dest_url,
-      bool copy) OVERRIDE;
-  virtual base::PlatformFileError CopyInForeignFile(
-        fileapi::FileSystemOperationContext* context,
-        const base::FilePath& src_file_path,
-        const fileapi::FileSystemURL& dest_url) OVERRIDE;
-  virtual base::PlatformFileError DeleteFile(
+      const StatusCallback& callback) OVERRIDE;
+  virtual bool MoveFileLocal(
       fileapi::FileSystemOperationContext* context,
-      const fileapi::FileSystemURL& url) OVERRIDE;
-  virtual base::PlatformFileError GetFileInfo(
+      const fileapi::FileSystemURL& src_url,
+      const fileapi::FileSystemURL& dest_url,
+      const StatusCallback& callback) OVERRIDE;
+  virtual bool CopyInForeignFile(
+      fileapi::FileSystemOperationContext* context,
+      const base::FilePath& src_file_path,
+      const fileapi::FileSystemURL& dest_url,
+      const StatusCallback& callback) OVERRIDE;
+  virtual bool DeleteFile(
       fileapi::FileSystemOperationContext* context,
       const fileapi::FileSystemURL& url,
-      base::PlatformFileInfo* file_info,
-      base::FilePath* platform_path) OVERRIDE;
-  virtual webkit_blob::ScopedFile CreateSnapshotFile(
+      const StatusCallback& callback) OVERRIDE;
+  virtual bool DeleteDirectory(
       fileapi::FileSystemOperationContext* context,
       const fileapi::FileSystemURL& url,
-      base::PlatformFileError* error,
-      base::PlatformFileInfo* file_info,
-      base::FilePath* platform_path) OVERRIDE;
+      const StatusCallback& callback) OVERRIDE;
+  virtual bool CreateSnapshotFile(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      const CreateSnapshotFileCallback& callback) OVERRIDE;
 
   // Uses the MIME sniffer code, which actually looks into the file,
   // to determine if it is really a media file (to avoid exposing
   // non-media files with a media file extension.)
   static base::PlatformFileError IsMediaFile(const base::FilePath& path);
 
+ protected:
+  // The following methods should only be called on the task runner thread.
+
+  // Necessary for copy/move to succeed.
+  virtual base::PlatformFileError CreateDirectorySync(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      bool exclusive,
+      bool recursive);
+  virtual base::PlatformFileError CopyOrMoveFileSync(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& src_url,
+      const fileapi::FileSystemURL& dest_url,
+      bool copy);
+  virtual base::PlatformFileError CopyInForeignFileSync(
+      fileapi::FileSystemOperationContext* context,
+      const base::FilePath& src_file_path,
+      const fileapi::FileSystemURL& dest_url);
+  virtual base::PlatformFileError GetFileInfoSync(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      base::PlatformFileInfo* file_info,
+      base::FilePath* platform_path);
+  // Called by GetFileInfoSync. Meant to be overridden by subclasses that
+  // have special mappings from URLs to platform paths (virtual filesystems).
+  virtual base::PlatformFileError GetLocalFilePath(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& file_system_url,
+      base::FilePath* local_file_path);
+  virtual base::PlatformFileError ReadDirectorySync(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      EntryList* file_list);
+  // Necessary for move to succeed.
+  virtual base::PlatformFileError DeleteDirectorySync(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url);
+  virtual base::PlatformFileError CreateSnapshotFileSync(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      base::PlatformFileInfo* file_info,
+      base::FilePath* platform_path,
+      scoped_refptr<webkit_blob::ShareableFileReference>* file_ref);
+
  private:
   // Like GetLocalFilePath(), but always take media_path_filter() into
   // consideration. If the media_path_filter() check fails, return
   // PLATFORM_FILE_ERROR_SECURITY. |local_file_path| does not have to exist.
   base::PlatformFileError GetFilteredLocalFilePath(
       fileapi::FileSystemOperationContext* context,
       const fileapi::FileSystemURL& file_system_url,
       base::FilePath* local_file_path);
 
   // Like GetLocalFilePath(), but if the file does not exist, then return
   // |failure_error|.
   // If |local_file_path| is a file, then take media_path_filter() into
   // consideration.
   // If the media_path_filter() check fails, return |failure_error|.
   // If |local_file_path| is a directory, return PLATFORM_FILE_OK.
   base::PlatformFileError GetFilteredLocalFilePathForExistingFileOrDirectory(
       fileapi::FileSystemOperationContext* context,
       const fileapi::FileSystemURL& file_system_url,
       base::PlatformFileError failure_error,
       base::FilePath* local_file_path);
 
+  virtual void CreateDirectoryOnTaskRunnerThread(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      bool exclusive,
+      bool recursive,
+      const StatusCallback& callback);
+  virtual void GetFileInfoOnTaskRunnerThread(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      const GetFileInfoCallback& callback);
+  virtual void ReadDirectoryOnTaskRunnerThread(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      const ReadDirectoryCallback& callback);
+  virtual void CopyOrMoveFileLocalOnTaskRunnerThread(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& src_url,
+      const fileapi::FileSystemURL& dest_url,
+      bool copy,
+      const StatusCallback& callback);
+  virtual void CopyInForeignFileOnTaskRunnerThread(
+      fileapi::FileSystemOperationContext* context,
+      const base::FilePath& src_file_path,
+      const fileapi::FileSystemURL& dest_url,
+      const StatusCallback& callback);
+  virtual void DeleteDirectoryOnTaskRunnerThread(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      const StatusCallback& callback);
+  virtual void CreateSnapshotFileOnTaskRunnerThread(
+      fileapi::FileSystemOperationContext* context,
+      const fileapi::FileSystemURL& url,
+      const CreateSnapshotFileCallback& callback);
+
+  base::WeakPtrFactory<NativeMediaFileUtil> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(NativeMediaFileUtil);
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_MEDIA_GALLERIES_FILEAPI_NATIVE_MEDIA_FILE_UTIL_H_