chromium/storage/browser/file_system/file_observers.h

// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef STORAGE_BROWSER_FILE_SYSTEM_FILE_OBSERVERS_H_
#define STORAGE_BROWSER_FILE_SYSTEM_FILE_OBSERVERS_H_

#include <stdint.h>

#include "base/component_export.h"

// TODO(kinuko): Split this file into per-observer multiple files.

namespace storage {

class FileSystemURL;

// An abstract interface to observe update operations.
//
// OnStartUpdate and OnEndUpdate are called once for each target url
// before and after following operations regardless of whether the operation
// is made recursively or not (i.e. StartUpdate() will be called only once
// for destination url regardless of whether it is recursive copy or not):
//  CreateFile(), CreateDirectory(),
//  Copy() (destination only),
//  Move() (both for source and destination),
//  Remove(), Write(), Truncate(), TouchFile()
//
// OnUpdate() is called each time the |url| is updated but works only for
// sandboxed files (where usage is tracked).
class COMPONENT_EXPORT(STORAGE_BROWSER) FileUpdateObserver { … };

// An abstract interface to observe file access.
// OnAccess is called whenever an operation reads file contents or metadata.
// (It is called only once per operation regardless of whether the operation
// is recursive or not)
class COMPONENT_EXPORT(STORAGE_BROWSER) FileAccessObserver { … };

// An abstract interface to observe file changes.
// Each method of this class is called once per file/directory is created,
// removed or modified.  For recursive operations each method is called for
// each subdirectory/subfile.  Currently ChangeObserver is only supported
// by the local sandbox file system.
class COMPONENT_EXPORT(STORAGE_BROWSER) FileChangeObserver { … };

}  // namespace storage

#endif  // STORAGE_BROWSER_FILE_SYSTEM_FILE_OBSERVERS_H_