| // Copyright 2013 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_CHROMEOS_FILE_MANAGER_FILE_WATCHER_H_ |
| #define CHROME_BROWSER_CHROMEOS_FILE_MANAGER_FILE_WATCHER_H_ |
| |
| #include <map> |
| #include <string> |
| |
| #include "base/callback_forward.h" |
| #include "base/files/file_path.h" |
| #include "base/files/file_path_watcher.h" |
| #include "base/memory/weak_ptr.h" |
| #include "base/sequenced_task_runner.h" |
| |
| namespace file_manager { |
| |
| // This class is used to watch changes in the given virtual path, remember |
| // what extensions are watching the path. |
| // |
| // For local files, the class maintains a FilePathWatcher instance and |
| // remembers what extensions are watching the path. |
| // |
| // For remote files (ex. files on Drive), the class just remembers what |
| // extensions are watching the path. The actual file watching for remote |
| // files is handled differently in EventRouter. |
| class FileWatcher { |
| public: |
| typedef base::Callback<void(bool success)> BoolCallback; |
| |
| // Creates a FileWatcher associated with the virtual path. |
| explicit FileWatcher(const base::FilePath& virtual_path); |
| |
| ~FileWatcher(); |
| |
| // Remembers that the extension of |extension_id| is watching the virtual |
| // path. |
| // |
| // If this function is called more than once with the same extension ID, |
| // the class increments the counter internally, and RemoveExtension() |
| // decrements the counter, and forgets the extension when the counter |
| // becomes zero. |
| void AddExtension(const std::string& extension_id); |
| |
| // Forgets that the extension of |extension_id| is watching the virtual path, |
| // or just decrements the internal counter for the extension ID. See the |
| // comment at AddExtension() for details. |
| void RemoveExtension(const std::string& extension_id); |
| |
| // Returns IDs of the extensions watching virtual_path. The returned list |
| // is sorted in the alphabetical order and contains no duplicates. |
| std::vector<std::string> GetExtensionIds() const; |
| |
| // Returns the virtual path associated with the FileWatcher. |
| const base::FilePath& virtual_path() const { return virtual_path_; } |
| |
| // Starts watching a local file at |local_path|. |file_watcher_callback| |
| // will be called when changes are notified. |
| // |
| // |callback| will be called with true, if the file watch is started |
| // successfully, or false if failed. |callback| must not be null. |
| void WatchLocalFile( |
| const base::FilePath& local_path, |
| const base::FilePathWatcher::Callback& file_watcher_callback, |
| const BoolCallback& callback); |
| |
| private: |
| // Called when a FilePathWatcher is created and started. |
| // |file_path_watcher| is NULL, if the watcher wasn't started successfully. |
| void OnWatcherStarted(const BoolCallback& callback, |
| base::FilePathWatcher* file_path_watcher); |
| |
| scoped_refptr<base::SequencedTaskRunner> sequenced_task_runner_; |
| base::FilePathWatcher* local_file_watcher_; |
| base::FilePath virtual_path_; |
| // Map of extension-id to counter. See the comment at AddExtension() for |
| // why we need to count. |
| typedef std::map<std::string, int> ExtensionCountMap; |
| ExtensionCountMap extensions_; |
| |
| // Note: This should remain the last member so it'll be destroyed and |
| // invalidate the weak pointers before any other members are destroyed. |
| base::WeakPtrFactory<FileWatcher> weak_ptr_factory_; |
| }; |
| |
| } // namespace file_manager |
| |
| #endif // CHROME_BROWSER_CHROMEOS_FILE_MANAGER_FILE_WATCHER_H_ |