[ew] Add basic classes.

webkit/browser/fileapi/file_system_backend.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_BROWSER_FILEAPI_FILE_SYSTEM_BACKEND_H_
 #define WEBKIT_BROWSER_FILEAPI_FILE_SYSTEM_BACKEND_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 15 matching lines @@
 namespace storage {
 
 class AsyncFileUtil;
 class CopyOrMoveFileValidatorFactory;
 class FileSystemURL;
 class FileStreamWriter;
 class FileSystemContext;
 class FileSystemFileUtil;
 class FileSystemOperation;
 class FileSystemQuotaUtil;
+class WatcherManager;
 
 // An interface for defining a file system backend.
 //
 // NOTE: when you implement a new FileSystemBackend for your own
 // FileSystem module, please contact to kinuko@chromium.org.
 //
 class STORAGE_EXPORT FileSystemBackend {
  public:
   // Callback for InitializeFileSystem.
   typedef base::Callback<void(const GURL& root_url,
@@ skipping 17 matching lines @@
   // If |mode| is CREATE_IF_NONEXISTENT calling this may also create the root
   // directory (and/or related database entries etc) for the filesystem if it
   // doesn't exist.
   virtual void ResolveURL(const FileSystemURL& url,
                           OpenFileSystemMode mode,
                           const OpenFileSystemCallback& callback) = 0;
 
   // Returns the specialized AsyncFileUtil for this backend.
   virtual AsyncFileUtil* GetAsyncFileUtil(FileSystemType type) = 0;
 
+  // Returns the specialized WatcherManager for this backend.
+  virtual WatcherManager* GetWatcherManager(FileSystemType type) = 0;
+
   // Returns the specialized CopyOrMoveFileValidatorFactory for this backend
   // and |type|.  If |error_code| is File::FILE_OK and the result is NULL,
   // then no validator is required.
   virtual CopyOrMoveFileValidatorFactory* GetCopyOrMoveFileValidatorFactory(
       FileSystemType type, base::File::Error* error_code) = 0;
 
   // Returns a new instance of the specialized FileSystemOperation for this
   // backend based on the given triplet of |origin_url|, |file_system_type|
   // and |virtual_path|. On failure to create a file system operation, set
   // |error_code| correspondingly.
@@ skipping 15 matching lines @@
   virtual bool HasInplaceCopyImplementation(FileSystemType type) const = 0;
 
   // Creates a new file stream reader for a given filesystem URL |url| with an
   // offset |offset|. |expected_modification_time| specifies the expected last
   // modification if the value is non-null, the reader will check the underlying
   // file's actual modification time to see if the file has been modified, and
   // if it does any succeeding read operations should fail with
   // ERR_UPLOAD_FILE_CHANGED error.
   // This method itself does *not* check if the given path exists and is a
   // regular file.
+  // The |length| argument says how many bytes are going to be read using the
+  // instance of the file stream reader. If unknown, then equal to -1.
   virtual scoped_ptr<storage::FileStreamReader> CreateFileStreamReader(
       const FileSystemURL& url,
       int64 offset,
       const base::Time& expected_modification_time,
       FileSystemContext* context) const = 0;
 
   // Creates a new file stream writer for a given filesystem URL |url| with an
   // offset |offset|.
   // This method itself does *not* check if the given path exists and is a
   // regular file.
@@ skipping 31 matching lines @@
         const std::string& extension_id) = 0;
   // Gets virtual path by known filesystem path. Returns false when filesystem
   // path is not exposed by this provider.
   virtual bool GetVirtualPath(const base::FilePath& file_system_path,
                               base::FilePath* virtual_path) = 0;
 };
 
 }  // namespace storage
 
 #endif  // WEBKIT_BROWSER_FILEAPI_FILE_SYSTEM_BACKEND_H_