1 // Copyright 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_LOCAL_FILE_SYNC_STATUS_H_ 6 #define CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_LOCAL_FILE_SYNC_STATUS_H_ 7 8 #include <map> 9 #include <set> 10 11 #include "base/basictypes.h" 12 #include "base/compiler_specific.h" 13 #include "base/gtest_prod_util.h" 14 #include "base/observer_list.h" 15 #include "base/threading/non_thread_safe.h" 16 #include "webkit/browser/fileapi/file_system_url.h" 17 18 namespace fileapi { 19 class FileSystemURL; 20 } 21 22 namespace sync_file_system { 23 24 // Represents local file sync status. 25 // This class is supposed to run only on IO thread. 26 // 27 // This class manages two important synchronization flags: writing (counter) 28 // and syncing (flag). Writing counter keeps track of which URL is in 29 // writing and syncing flag indicates which URL is in syncing. 30 // 31 // An entry can have multiple writers but sync is exclusive and cannot overwrap 32 // with any writes or syncs. 33 class LocalFileSyncStatus 34 : public base::NonThreadSafe { 35 public: 36 typedef std::pair<GURL, fileapi::FileSystemType> OriginAndType; 37 38 class Observer { 39 public: Observer()40 Observer() {} ~Observer()41 virtual ~Observer() {} 42 virtual void OnSyncEnabled(const fileapi::FileSystemURL& url) = 0; 43 virtual void OnWriteEnabled(const fileapi::FileSystemURL& url) = 0; 44 private: 45 DISALLOW_COPY_AND_ASSIGN(Observer); 46 }; 47 48 LocalFileSyncStatus(); 49 ~LocalFileSyncStatus(); 50 51 // Increment writing counter for |url|. 52 // This should not be called if the |url| is not writable. 53 void StartWriting(const fileapi::FileSystemURL& url); 54 55 // Decrement writing counter for |url|. 56 void EndWriting(const fileapi::FileSystemURL& url); 57 58 // Start syncing for |url| and disable writing. 59 // This should not be called if |url| is in syncing or in writing. 60 void StartSyncing(const fileapi::FileSystemURL& url); 61 62 // Clears the syncing flag for |url| and enable writing. 63 void EndSyncing(const fileapi::FileSystemURL& url); 64 65 // Returns true if the |url| or its parent or child is in writing. 66 bool IsWriting(const fileapi::FileSystemURL& url) const; 67 68 // Returns true if the |url| is enabled for writing (i.e. not in syncing). 69 bool IsWritable(const fileapi::FileSystemURL& url) const; 70 71 // Returns true if the |url| is enabled for syncing (i.e. neither in 72 // syncing nor writing). 73 bool IsSyncable(const fileapi::FileSystemURL& url) const; 74 75 void AddObserver(Observer* observer); 76 void RemoveObserver(Observer* observer); 77 78 private: 79 FRIEND_TEST_ALL_PREFIXES(LocalFileSyncStatusTest, WritingOnPathsWithPeriod); 80 FRIEND_TEST_ALL_PREFIXES(LocalFileSyncStatusTest, SyncingOnPathsWithPeriod); 81 82 typedef std::set<base::FilePath> PathSet; 83 typedef std::map<OriginAndType, PathSet> URLSet; 84 85 typedef std::map<base::FilePath, int64> PathBucket; 86 typedef std::map<OriginAndType, PathBucket> URLBucket; 87 88 bool IsChildOrParentWriting(const fileapi::FileSystemURL& url) const; 89 bool IsChildOrParentSyncing(const fileapi::FileSystemURL& url) const; 90 91 // If this count is non-zero positive there're ongoing write operations. 92 URLBucket writing_; 93 94 // If this flag is set sync process is running on the file. 95 URLSet syncing_; 96 97 ObserverList<Observer> observer_list_; 98 99 DISALLOW_COPY_AND_ASSIGN(LocalFileSyncStatus); 100 }; 101 102 } // namespace sync_file_system 103 104 #endif // CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_LOCAL_FILE_SYNC_STATUS_H_ 105