Add database recovery for FileSystemDirectoryDatabase.

webkit/fileapi/file_system_directory_database.h

 // Copyright (c) 2012 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 WEBKIT_FILEAPI_FILE_SYSTEM_DIRECTORY_DATABASE_H_
 #define WEBKIT_FILEAPI_FILE_SYSTEM_DIRECTORY_DATABASE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 14 matching lines @@
 namespace fileapi {
 
 // This class WILL NOT protect you against producing directory loops, giving an
 // empty directory a backing data file, giving two files the same backing file,
 // or pointing to a nonexistent backing file.  It does no file IO other than
 // that involved with talking to its underlying database.  It does not create or
 // in any way touch real files; it only creates path entries in its database.
 
 // TODO(ericu): Safe mode, which does more checks such as the above on debug
 // builds.
-// TODO(ericu): FSCK, for a full-database check [data file validation possibly
-// done elsewhere].
 // TODO(ericu): Add a method that will give a unique filename for a data file.
 class FileSystemDirectoryDatabase {
  public:
   typedef int64 FileId;
 
   struct FileInfo {
     FileInfo();
     ~FileInfo();
 
     bool is_directory() const {
@@ skipping 32 matching lines @@
   // another file [also not a directory]; we need to alter two files' info in a
   // single transaction to avoid weird backing file references in the event of a
   // partial failure.
   bool OverwritingMoveFile(FileId src_file_id, FileId dest_file_id);
 
   // This produces the series 0, 1, 2..., starting at 0 when the underlying
   // filesystem is first created, and maintaining state across
   // creation/destruction of FileSystemDirectoryDatabase objects.
   bool GetNextInteger(int64* next);
 
+  // Returns true if the database looks consistent with local filesystem.
+  bool IsFileSystemConsistent();
+
   static bool DestroyDatabase(const FilePath& path);
 
  private:
   enum RecoveryOption {
     DELETE_ON_CORRUPTION,
+    REPAIR_ON_CORRUPTION,
     FAIL_ON_CORRUPTION,
   };
 
+  friend class FileSystemDirectoryDatabaseTest;
+
   bool Init(RecoveryOption recovery_option);
+  bool RepairDatabase(const std::string& db_path);
   void ReportInitStatus(const leveldb::Status& status);
   bool StoreDefaultValues();
   bool GetLastFileId(FileId* file_id);
   bool VerifyIsDirectory(FileId file_id);
   bool AddFileInfoHelper(
       const FileInfo& info, FileId file_id, leveldb::WriteBatch* batch);
   bool RemoveFileInfoHelper(FileId file_id, leveldb::WriteBatch* batch);
   void HandleError(const tracked_objects::Location& from_here,
                    const leveldb::Status& status);
 
   FilePath filesystem_data_directory_;
   scoped_ptr<leveldb::DB> db_;
   base::Time last_reported_time_;
   DISALLOW_COPY_AND_ASSIGN(FileSystemDirectoryDatabase);
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_FILE_SYSTEM_DIRECTORY_DATABASE_H_