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_CHROMEOS_FILEAPI_FILE_SYSTEM_BACKEND_H_ 6 #define CHROME_BROWSER_CHROMEOS_FILEAPI_FILE_SYSTEM_BACKEND_H_ 7 8 #include <string> 9 #include <vector> 10 11 #include "base/compiler_specific.h" 12 #include "base/files/file_path.h" 13 #include "base/memory/scoped_ptr.h" 14 #include "storage/browser/fileapi/file_system_backend.h" 15 #include "storage/browser/fileapi/task_runner_bound_observer_list.h" 16 #include "storage/browser/quota/special_storage_policy.h" 17 #include "storage/common/fileapi/file_system_types.h" 18 19 namespace storage { 20 class CopyOrMoveFileValidatorFactory; 21 class ExternalMountPoints; 22 class FileSystemURL; 23 class WatcherManager; 24 } // namespace storage 25 26 namespace chromeos { 27 28 class FileSystemBackendDelegate; 29 class FileAccessPermissions; 30 31 // FileSystemBackend is a Chrome OS specific implementation of 32 // ExternalFileSystemBackend. This class is responsible for a 33 // number of things, including: 34 // 35 // - Add system mount points 36 // - Grant/revoke/check file access permissions 37 // - Create FileSystemOperation per file system type 38 // - Create FileStreamReader/Writer per file system type 39 // 40 // Chrome OS specific mount points: 41 // 42 // "Downloads" is a mount point for user's Downloads directory on the local 43 // disk, where downloaded files are stored by default. 44 // 45 // "archive" is a mount point for an archive file, such as a zip file. This 46 // mount point exposes contents of an archive file via cros_disks and AVFS 47 // <http://avf.sourceforge.net/>. 48 // 49 // "removable" is a mount point for removable media such as an SD card. 50 // Insertion and removal of removable media are handled by cros_disks. 51 // 52 // "oem" is a read-only mount point for a directory containing OEM data. 53 // 54 // "drive" is a mount point for Google Drive. Drive is integrated with the 55 // FileSystem API layer via drive::FileSystemProxy. This mount point is added 56 // by drive::DriveIntegrationService. 57 // 58 // These mount points are placed under the "external" namespace, and file 59 // system URLs for these mount points look like: 60 // 61 // filesystem:<origin>/external/<mount_name>/... 62 // 63 class FileSystemBackend : public storage::ExternalFileSystemBackend { 64 public: 65 using storage::FileSystemBackend::OpenFileSystemCallback; 66 67 // FileSystemBackend will take an ownership of a |mount_points| 68 // reference. On the other hand, |system_mount_points| will be kept as a raw 69 // pointer and it should outlive FileSystemBackend instance. 70 // The ownerships of |drive_delegate| and |file_system_provider_delegate| are 71 // also taken. 72 FileSystemBackend( 73 FileSystemBackendDelegate* drive_delegate, 74 FileSystemBackendDelegate* file_system_provider_delegate, 75 FileSystemBackendDelegate* mtp_delegate, 76 scoped_refptr<storage::SpecialStoragePolicy> special_storage_policy, 77 scoped_refptr<storage::ExternalMountPoints> mount_points, 78 storage::ExternalMountPoints* system_mount_points); 79 virtual ~FileSystemBackend(); 80 81 // Adds system mount points, such as "archive", and "removable". This 82 // function is no-op if these mount points are already present. 83 void AddSystemMountPoints(); 84 85 // Returns true if CrosMountpointProvider can handle |url|, i.e. its 86 // file system type matches with what this provider supports. 87 // This could be called on any threads. 88 static bool CanHandleURL(const storage::FileSystemURL& url); 89 90 // storage::FileSystemBackend overrides. 91 virtual bool CanHandleType(storage::FileSystemType type) const OVERRIDE; 92 virtual void Initialize(storage::FileSystemContext* context) OVERRIDE; 93 virtual void ResolveURL(const storage::FileSystemURL& url, 94 storage::OpenFileSystemMode mode, 95 const OpenFileSystemCallback& callback) OVERRIDE; 96 virtual storage::AsyncFileUtil* GetAsyncFileUtil( 97 storage::FileSystemType type) OVERRIDE; 98 virtual storage::WatcherManager* GetWatcherManager( 99 storage::FileSystemType type) OVERRIDE; 100 virtual storage::CopyOrMoveFileValidatorFactory* 101 GetCopyOrMoveFileValidatorFactory(storage::FileSystemType type, 102 base::File::Error* error_code) OVERRIDE; 103 virtual storage::FileSystemOperation* CreateFileSystemOperation( 104 const storage::FileSystemURL& url, 105 storage::FileSystemContext* context, 106 base::File::Error* error_code) const OVERRIDE; 107 virtual bool SupportsStreaming( 108 const storage::FileSystemURL& url) const OVERRIDE; 109 virtual bool HasInplaceCopyImplementation( 110 storage::FileSystemType type) const OVERRIDE; 111 virtual scoped_ptr<storage::FileStreamReader> CreateFileStreamReader( 112 const storage::FileSystemURL& path, 113 int64 offset, 114 int64 max_bytes_to_read, 115 const base::Time& expected_modification_time, 116 storage::FileSystemContext* context) const OVERRIDE; 117 virtual scoped_ptr<storage::FileStreamWriter> CreateFileStreamWriter( 118 const storage::FileSystemURL& url, 119 int64 offset, 120 storage::FileSystemContext* context) const OVERRIDE; 121 virtual storage::FileSystemQuotaUtil* GetQuotaUtil() OVERRIDE; 122 virtual const storage::UpdateObserverList* GetUpdateObservers( 123 storage::FileSystemType type) const OVERRIDE; 124 virtual const storage::ChangeObserverList* GetChangeObservers( 125 storage::FileSystemType type) const OVERRIDE; 126 virtual const storage::AccessObserverList* GetAccessObservers( 127 storage::FileSystemType type) const OVERRIDE; 128 129 // storage::ExternalFileSystemBackend overrides. 130 virtual bool IsAccessAllowed( 131 const storage::FileSystemURL& url) const OVERRIDE; 132 virtual std::vector<base::FilePath> GetRootDirectories() const OVERRIDE; 133 virtual void GrantFullAccessToExtension( 134 const std::string& extension_id) OVERRIDE; 135 virtual void GrantFileAccessToExtension( 136 const std::string& extension_id, 137 const base::FilePath& virtual_path) OVERRIDE; 138 virtual void RevokeAccessForExtension( 139 const std::string& extension_id) OVERRIDE; 140 virtual bool GetVirtualPath(const base::FilePath& filesystem_path, 141 base::FilePath* virtual_path) OVERRIDE; 142 virtual void GetRedirectURLForContents( 143 const storage::FileSystemURL& url, 144 const storage::URLCallback& callback) OVERRIDE; 145 146 private: 147 scoped_refptr<storage::SpecialStoragePolicy> special_storage_policy_; 148 scoped_ptr<FileAccessPermissions> file_access_permissions_; 149 scoped_ptr<storage::AsyncFileUtil> local_file_util_; 150 151 // The delegate instance for the drive file system related operations. 152 scoped_ptr<FileSystemBackendDelegate> drive_delegate_; 153 154 // The delegate instance for the provided file system related operations. 155 scoped_ptr<FileSystemBackendDelegate> file_system_provider_delegate_; 156 157 // The delegate instance for the MTP file system related operations. 158 scoped_ptr<FileSystemBackendDelegate> mtp_delegate_; 159 160 // Mount points specific to the owning context (i.e. per-profile mount 161 // points). 162 // 163 // It is legal to have mount points with the same name as in 164 // system_mount_points_. Also, mount point paths may overlap with mount point 165 // paths in system_mount_points_. In both cases mount points in 166 // |mount_points_| will have a priority. 167 // E.g. if |mount_points_| map 'foo1' to '/foo/foo1' and 168 // |file_system_mount_points_| map 'xxx' to '/foo/foo1/xxx', |GetVirtualPaths| 169 // will resolve '/foo/foo1/xxx/yyy' as 'foo1/xxx/yyy' (i.e. the mapping from 170 // |mount_points_| will be used). 171 scoped_refptr<storage::ExternalMountPoints> mount_points_; 172 173 // Globally visible mount points. System MountPonts instance should outlive 174 // all FileSystemBackend instances, so raw pointer is safe. 175 storage::ExternalMountPoints* system_mount_points_; 176 177 DISALLOW_COPY_AND_ASSIGN(FileSystemBackend); 178 }; 179 180 } // namespace chromeos 181 182 #endif // CHROME_BROWSER_CHROMEOS_FILEAPI_FILE_SYSTEM_BACKEND_H_ 183
