1 // Copyright (c) 2012 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_CHROMEOS_DRIVE_FILE_CACHE_H_ 6 #define CHROME_BROWSER_CHROMEOS_DRIVE_FILE_CACHE_H_ 7 8 #include <set> 9 #include <string> 10 11 #include "base/files/file_path.h" 12 #include "base/memory/scoped_ptr.h" 13 #include "base/memory/weak_ptr.h" 14 #include "chrome/browser/chromeos/drive/file_errors.h" 15 #include "chrome/browser/chromeos/drive/resource_metadata_storage.h" 16 17 namespace base { 18 class SequencedTaskRunner; 19 } // namespace base 20 21 namespace drive { 22 23 class FileCacheEntry; 24 25 namespace internal { 26 27 // Interface class used for getting the free disk space. Tests can inject an 28 // implementation that reports fake free disk space. 29 class FreeDiskSpaceGetterInterface { 30 public: 31 virtual ~FreeDiskSpaceGetterInterface() {} 32 virtual int64 AmountOfFreeDiskSpace() = 0; 33 }; 34 35 // FileCache is used to maintain cache states of FileSystem. 36 // 37 // All non-static public member functions, unless mentioned otherwise (see 38 // GetCacheFilePath() for example), should be run with |blocking_task_runner|. 39 class FileCache { 40 public: 41 // Enum defining type of file operation e.g. copy or move, etc. 42 enum FileOperationType { 43 FILE_OPERATION_MOVE = 0, 44 FILE_OPERATION_COPY, 45 }; 46 47 typedef ResourceMetadataStorage::CacheEntryIterator Iterator; 48 49 // |cache_file_directory| stores cached files. 50 // 51 // |blocking_task_runner| indicates the blocking worker pool for cache 52 // operations. All operations on this FileCache must be run on this runner. 53 // Must not be null. 54 // 55 // |free_disk_space_getter| is used to inject a custom free disk space 56 // getter for testing. NULL must be passed for production code. 57 // 58 // Must be called on the UI thread. 59 FileCache(ResourceMetadataStorage* storage, 60 const base::FilePath& cache_file_directory, 61 base::SequencedTaskRunner* blocking_task_runner, 62 FreeDiskSpaceGetterInterface* free_disk_space_getter); 63 64 // Returns true if the given path is under drive cache directory, i.e. 65 // <user_profile_dir>/GCache/v1 66 // 67 // Can be called on any thread. 68 bool IsUnderFileCacheDirectory(const base::FilePath& path) const; 69 70 // Gets the cache entry for file corresponding to |id| and returns true if 71 // entry exists in cache map. 72 bool GetCacheEntry(const std::string& id, FileCacheEntry* entry); 73 74 // Returns an object to iterate over entries. 75 scoped_ptr<Iterator> GetIterator(); 76 77 // Frees up disk space to store a file with |num_bytes| size content, while 78 // keeping cryptohome::kMinFreeSpaceInBytes bytes on the disk, if needed. 79 // Returns true if we successfully manage to have enough space, otherwise 80 // false. 81 bool FreeDiskSpaceIfNeededFor(int64 num_bytes); 82 83 // Checks if file corresponding to |id| exists in cache, and returns 84 // FILE_ERROR_OK with |cache_file_path| storing the path to the file. 85 // |cache_file_path| must not be null. 86 FileError GetFile(const std::string& id, base::FilePath* cache_file_path); 87 88 // Stores |source_path| as a cache of the remote content of the file 89 // with |id| and |md5|. 90 FileError Store(const std::string& id, 91 const std::string& md5, 92 const base::FilePath& source_path, 93 FileOperationType file_operation_type); 94 95 // Pins the specified entry. 96 FileError Pin(const std::string& id); 97 98 // Unpins the specified entry. 99 FileError Unpin(const std::string& id); 100 101 // Sets the state of the cache entry corresponding to |id| as mounted. 102 FileError MarkAsMounted(const std::string& id, 103 base::FilePath* cache_file_path); 104 105 // Sets the state of the cache entry corresponding to file_path as unmounted. 106 FileError MarkAsUnmounted(const base::FilePath& file_path); 107 108 // Marks the specified entry dirty. 109 FileError MarkDirty(const std::string& id); 110 111 // Clears dirty state of the specified entry and updates its MD5. 112 FileError ClearDirty(const std::string& id, const std::string& md5); 113 114 // Removes the specified cache entry and delete cache files if available. 115 FileError Remove(const std::string& id); 116 117 // Removes all the files in the cache directory and cache entries in DB. 118 bool ClearAll(); 119 120 // Initializes the cache. Returns true on success. 121 bool Initialize(); 122 123 // Destroys this cache. This function posts a task to the blocking task 124 // runner to safely delete the object. 125 // Must be called on the UI thread. 126 void Destroy(); 127 128 // Moves files in the cache directory which are not managed by FileCache to 129 // |dest_directory|. 130 // |recovered_cache_info| should contain cache info recovered from the trashed 131 // metadata DB. It is used to ignore non-dirty files. 132 bool RecoverFilesFromCacheDirectory( 133 const base::FilePath& dest_directory, 134 const ResourceMetadataStorage::RecoveredCacheInfoMap& 135 recovered_cache_info); 136 137 private: 138 friend class FileCacheTest; 139 friend class FileCacheTestOnUIThread; 140 141 ~FileCache(); 142 143 // Returns absolute path of the file if it were cached or to be cached. 144 // 145 // Can be called on any thread. 146 base::FilePath GetCacheFilePath(const std::string& id) const; 147 148 // Checks whether the current thread is on the right sequenced worker pool 149 // with the right sequence ID. If not, DCHECK will fail. 150 void AssertOnSequencedWorkerPool(); 151 152 // Destroys the cache on the blocking pool. 153 void DestroyOnBlockingPool(); 154 155 // Returns true if we have sufficient space to store the given number of 156 // bytes, while keeping cryptohome::kMinFreeSpaceInBytes bytes on the disk. 157 bool HasEnoughSpaceFor(int64 num_bytes, const base::FilePath& path); 158 159 // Renames cache files from old "prefix:id.md5" format to the new format. 160 // TODO(hashimoto): Remove this method at some point. 161 bool RenameCacheFilesToNewFormat(); 162 163 const base::FilePath cache_file_directory_; 164 165 scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_; 166 167 ResourceMetadataStorage* storage_; 168 169 FreeDiskSpaceGetterInterface* free_disk_space_getter_; // Not owned. 170 171 // IDs of files marked mounted. 172 std::set<std::string> mounted_files_; 173 174 // Note: This should remain the last member so it'll be destroyed and 175 // invalidate its weak pointers before any other members are destroyed. 176 base::WeakPtrFactory<FileCache> weak_ptr_factory_; 177 DISALLOW_COPY_AND_ASSIGN(FileCache); 178 }; 179 180 } // namespace internal 181 } // namespace drive 182 183 #endif // CHROME_BROWSER_CHROMEOS_DRIVE_FILE_CACHE_H_ 184
