public LevelDBBlockchain(string path) { header_index.Add(GenesisBlock.Hash); Version version; Slice value; db = DB.Open(path, new Options { CreateIfMissing = true }); if (db.TryGet(ReadOptions.Default, SliceBuilder.Begin(DataEntryPrefix.SYS_Version), out value) && Version.TryParse(value.ToString(), out version) && version >= Version.Parse("1.5")) { ReadOptions options = new ReadOptions { FillCache = false }; value = db.Get(options, SliceBuilder.Begin(DataEntryPrefix.SYS_CurrentBlock)); UInt256 current_header_hash = new UInt256(value.ToArray().Take(32).ToArray()); this.current_block_height = value.ToArray().ToUInt32(32); uint current_header_height = current_block_height; if (db.TryGet(options, SliceBuilder.Begin(DataEntryPrefix.SYS_CurrentHeader), out value)) { current_header_hash = new UInt256(value.ToArray().Take(32).ToArray()); current_header_height = value.ToArray().ToUInt32(32); } foreach (UInt256 hash in db.Find(options, SliceBuilder.Begin(DataEntryPrefix.IX_HeaderHashList), (k, v) => { using (MemoryStream ms = new MemoryStream(v.ToArray(), false)) using (BinaryReader r = new BinaryReader(ms)) { return(new { Index = k.ToArray().ToUInt32(1), Hashes = r.ReadSerializableArray <UInt256>() }); } }).OrderBy(p => p.Index).SelectMany(p => p.Hashes).ToArray()) { if (!hash.Equals(GenesisBlock.Hash)) { header_index.Add(hash); } stored_header_count++; } if (stored_header_count == 0) { Header[] headers = db.Find(options, SliceBuilder.Begin(DataEntryPrefix.DATA_Block), (k, v) => Header.FromTrimmedData(v.ToArray(), sizeof(long))).OrderBy(p => p.Index).ToArray(); for (int i = 1; i < headers.Length; i++) { header_index.Add(headers[i].Hash); } } else if (current_header_height >= stored_header_count) { for (UInt256 hash = current_header_hash; hash != header_index[(int)stored_header_count - 1];) { Header header = Header.FromTrimmedData(db.Get(options, SliceBuilder.Begin(DataEntryPrefix.DATA_Block).Add(hash)).ToArray(), sizeof(long)); header_index.Insert((int)stored_header_count, hash); hash = header.PrevHash; } } } else { WriteBatch batch = new WriteBatch(); ReadOptions options = new ReadOptions { FillCache = false }; using (Iterator it = db.NewIterator(options)) { for (it.SeekToFirst(); it.Valid(); it.Next()) { batch.Delete(it.Key()); } } db.Write(WriteOptions.Default, batch); Persist(GenesisBlock); db.Put(WriteOptions.Default, SliceBuilder.Begin(DataEntryPrefix.SYS_Version), GetType().GetTypeInfo().Assembly.GetName().Version.ToString()); } thread_persistence = new Thread(PersistBlocks); thread_persistence.Name = "LevelDBBlockchain.PersistBlocks"; thread_persistence.Start(); }