Add database recovery for FileSystemOriginDatabase

webkit/fileapi/file_system_directory_database.h

 // Copyright (c) 2011 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>
 
 #include "base/file_path.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time.h"
 #include "third_party/leveldatabase/src/include/leveldb/db.h"
 
 namespace tracked_objects {
 class Location;
 }
 
 namespace leveldb {
+class Status;

[jsbell, 2012/03/10 00:54:50]

This can be removed from the .h now.

[tzik, 2012/03/13 06:40:29]

Done.

 class WriteBatch;
 }
 
 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;
+  enum RecoveringOption {

[ericu, 2012/03/12 19:46:01]

I'd prefer RecoveryOption to RecoveringOption, and I think that
DELETE_ON_CORRUPTION is better than REBUILD_ON_CORRUPTION, since it makes it
clear that there is data loss.  And how about FAIL_ON_CORRUPTION instead of
LEAVE_ON_CORRUPTION?

[tzik, 2012/03/13 06:40:29]

Done.

+    REBUILD_ON_CORRUPTION,
+    LEAVE_ON_CORRUPTION,
+  };
 
   struct FileInfo {
     FileInfo();
     ~FileInfo();
 
     bool is_directory() const {
       return data_path.empty();
     }
 
     FileId parent_id;
@@ skipping 30 matching lines @@
   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);
 
   static bool DestroyDatabase(const FilePath& path);
 
  private:
-  bool Init();
+  bool Init(RecoveringOption recovering_option);
   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,
                    leveldb::Status status);
 
   std::string path_;
   scoped_ptr<leveldb::DB> db_;
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_FILE_SYSTEM_DIRECTORY_DATABASE_H_