Revert 274735 "Use FSEvents for recursive file watch on Mac"

trunk/src/base/files/file_path_watcher_fsevents.h

-// Copyright 2014 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 BASE_FILES_FILE_PATH_WATCHER_FSEVENTS_H_
-#define BASE_FILES_FILE_PATH_WATCHER_FSEVENTS_H_
-
-#include <CoreServices/CoreServices.h>
-
-#include <vector>
-
-#include "base/files/file_path.h"
-#include "base/files/file_path_watcher.h"
-
-namespace base {
-
-// Mac-specific file watcher implementation based on FSEvents.
-// There are trade-offs between the FSEvents implementation and a kqueue
-// implementation. The biggest issues are that FSEvents on 10.6 sometimes drops
-// events and kqueue does not trigger for modifications to a file in a watched
-// directory. See file_path_watcher_mac.cc for the code that decides when to
-// use which one.
-class FilePathWatcherFSEvents : public FilePathWatcher::PlatformDelegate {
- public:
-  FilePathWatcherFSEvents();
-
-  // Called from the FSEvents callback whenever there is a change to the paths.
-  void OnFilePathsChanged(const std::vector<FilePath>& paths);
-
-  // (Re-)Initialize the event stream to start reporting events from
-  // |start_event|.
-  void UpdateEventStream(FSEventStreamEventId start_event);
-
-  // Returns true if resolving the target path got a different result than
-  // last time it was done.
-  bool ResolveTargetPath();
-
-  // FilePathWatcher::PlatformDelegate overrides.
-  virtual bool Watch(const FilePath& path,
-                     bool recursive,
-                     const FilePathWatcher::Callback& callback) OVERRIDE;
-  virtual void Cancel() OVERRIDE;
-
- private:
-  virtual ~FilePathWatcherFSEvents();
-
-  // Destroy the event stream.
-  void DestroyEventStream();
-
-  // Start watching the FSEventStream.
-  void StartEventStream(FSEventStreamEventId start_event);
-
-  // Cleans up and stops the event stream.
-  virtual void CancelOnMessageLoopThread() OVERRIDE;
-
-  // Callback to notify upon changes.
-  FilePathWatcher::Callback callback_;
-
-  // Target path to watch (passed to callback).
-  FilePath target_;
-
-  // Target path with all symbolic links resolved.
-  FilePath resolved_target_;
-
-  // Backend stream we receive event callbacks from (strong reference).
-  FSEventStreamRef fsevent_stream_;
-
-  DISALLOW_COPY_AND_ASSIGN(FilePathWatcherFSEvents);
-};
-
-}  // namespace base
-
-#endif  // BASE_FILES_FILE_PATH_WATCHER_FSEVENTS_H_