[IndexedDB] Integrating failures and corruption with transaction

content/browser/indexed_db/indexed_db_backing_store.h

 // Copyright (c) 2013 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 CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_BACKING_STORE_H_
 #define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_BACKING_STORE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 300 matching lines @@
     bool Continue(const IndexedDBKey* key,
                   IteratorState state,
                   leveldb::Status* s) {
       return Continue(key, NULL, state, s);
     }
     bool Continue(const IndexedDBKey* key,
                   const IndexedDBKey* primary_key,
                   IteratorState state,
                   leveldb::Status*);
     bool Advance(uint32_t count, leveldb::Status*);
+    // Returns true when no error and we haven't reached the end of the data.
     bool FirstSeek(leveldb::Status*);
 
     virtual std::unique_ptr<Cursor> Clone() const = 0;
     virtual const IndexedDBKey& primary_key() const;
     virtual IndexedDBValue* value() = 0;
     virtual const RecordIdentifier& record_identifier() const;
     virtual bool LoadCurrentRow(leveldb::Status* s) = 0;
 
    protected:
     Cursor(scoped_refptr<IndexedDBBackingStore> backing_store,
@@ skipping 12 matching lines @@
     IndexedDBBackingStore* backing_store_;
     Transaction* transaction_;
     int64_t database_id_;
     const CursorOptions cursor_options_;
     std::unique_ptr<LevelDBIterator> iterator_;
     std::unique_ptr<IndexedDBKey> current_key_;
     IndexedDBBackingStore::RecordIdentifier record_identifier_;
 
    private:
     // For cursors with direction Next or NextNoDuplicate.
+    // Returns true when no error and we haven't reached the end of the data.

[cmumford, 2016/11/21 18:29:22]

Do you think it would be clearer if this instead returned an enumeration? Maybe
something like: ERROR, SUCCESS, LAST_KEY (names are crappy, but you get the
idea).

[dmurph, 2016/11/22 23:33:10]

mmmm this is a large change, as I'll want to change all of the Advance/Continue
calls above. Effects lots of files. I'll change the private ones here only for
now.

[cmumford, 2016/11/28 20:48:25]

Acknowledged.

     bool ContinueNext(const IndexedDBKey* key,
                       const IndexedDBKey* primary_key,
                       IteratorState state,
                       leveldb::Status*);
     // For cursors with direction Prev or PrevNoDuplicate. The PrevNoDuplicate
     // case has additional complexity of not being symmetric with
     // NextNoDuplicate.
+    // Returns true when no error and we haven't reached the end of the data.
     bool ContinuePrevious(const IndexedDBKey* key,
                           const IndexedDBKey* primary_key,
                           IteratorState state,
                           leveldb::Status*);
 
     DISALLOW_COPY_AND_ASSIGN(Cursor);
   };
 
   const url::Origin& origin() const { return origin_; }
   IndexedDBFactory* factory() const { return indexed_db_factory_; }
@@ skipping 39 matching lines @@
   // Compact is public for testing.
   virtual void Compact();
   virtual std::vector<base::string16> GetDatabaseNames(leveldb::Status*);
   virtual leveldb::Status GetIDBDatabaseMetaData(
       const base::string16& name,
       IndexedDBDatabaseMetadata* metadata,
       bool* success) WARN_UNUSED_RESULT;
   virtual leveldb::Status CreateIDBDatabaseMetaData(const base::string16& name,
                                                     int64_t version,
                                                     int64_t* row_id);
-  virtual bool UpdateIDBDatabaseIntVersion(
+  virtual void UpdateIDBDatabaseIntVersion(
       IndexedDBBackingStore::Transaction* transaction,
       int64_t row_id,
       int64_t version);
   virtual leveldb::Status DeleteDatabase(const base::string16& name);
 
   // Assumes caller has already closed the backing store.
   static leveldb::Status DestroyBackingStore(const base::FilePath& path_base,
                                              const url::Origin& origin);
   static bool RecordCorruptionInfo(const base::FilePath& path_base,
                                    const url::Origin& origin,
@@ skipping 255 matching lines @@
   // complete. While > 0, temporary journal entries may exist so out-of-band
   // journal cleaning must be deferred.
   size_t committing_transaction_count_;
 
   DISALLOW_COPY_AND_ASSIGN(IndexedDBBackingStore);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_BACKING_STORE_H_