make transaction attributes contains more bytes; try to fix LevelDBEx…

…ception "Corruption: unknown WriteBatch tag"; fix bug of changing password;

src/AntShares/Core/TransactionAttribute.cs

@@ -27,6 +27,8 @@ public int Size
             {
                 if (Usage == TransactionAttributeUsage.ContractHash || Usage == TransactionAttributeUsage.ECDH02 || Usage == TransactionAttributeUsage.ECDH03 || Usage == TransactionAttributeUsage.Vote || (Usage >= TransactionAttributeUsage.Hash1 && Usage <= TransactionAttributeUsage.Hash15))
                     return sizeof(TransactionAttributeUsage) + 32;
+                else if (Usage == TransactionAttributeUsage.CertUrl || Usage == TransactionAttributeUsage.DescriptionUrl)
+                    return sizeof(TransactionAttributeUsage) + sizeof(byte) + Data.Length;
                 else
                     return sizeof(TransactionAttributeUsage) + Data.Length.GetVarSize() + Data.Length;
             }
@@ -42,9 +44,9 @@ void ISerializable.Deserialize(BinaryReader reader)
             else if (Usage == TransactionAttributeUsage.Script)
                 Data = reader.ReadVarBytes(ushort.MaxValue);
             else if (Usage == TransactionAttributeUsage.CertUrl || Usage == TransactionAttributeUsage.DescriptionUrl)
-                Data = reader.ReadVarBytes(byte.MaxValue);
+                Data = reader.ReadBytes(reader.ReadByte());
             else if (Usage == TransactionAttributeUsage.Description || Usage >= TransactionAttributeUsage.Remark)
-                Data = reader.ReadVarBytes(byte.MaxValue);
+                Data = reader.ReadVarBytes(ushort.MaxValue);
             else
                 throw new FormatException();
         }
@@ -57,7 +59,7 @@ void ISerializable.Serialize(BinaryWriter writer)
             else if (Usage == TransactionAttributeUsage.CertUrl || Usage == TransactionAttributeUsage.DescriptionUrl)
                 writer.Write((byte)Data.Length);
             else if (Usage == TransactionAttributeUsage.Description || Usage >= TransactionAttributeUsage.Remark)
-                writer.Write((byte)Data.Length);
+                writer.WriteVarInt(Data.Length);
             if (Usage == TransactionAttributeUsage.ECDH02 || Usage == TransactionAttributeUsage.ECDH03)
                 writer.Write(Data, 1, 32);
             else

src/AntShares/Implementations/Blockchains/LevelDB/LevelDBBlockchain.cs

@@ -589,7 +589,24 @@ private void Persist(Block block)
                 batch.Put(SliceBuilder.Begin(DataEntryPrefix.ST_QuantityIssued).Add(quantity.Key), (GetQuantityIssued(quantity.Key) + quantity.Value).GetData());
             }
             batch.Put(SliceBuilder.Begin(DataEntryPrefix.SYS_CurrentBlock), SliceBuilder.Begin().Add(block.Hash).Add(block.Height));
-            db.Write(WriteOptions.Default, batch);
+            // There's a bug in .Net Core.
+            // When calling DB.Write(), it will throw LevelDBException sometimes.
+            // But when you try to catch the exception, the bug disappears.
+            // We shall remove the "try...catch" clause when Microsoft fix the bug.
+            byte retry = 0;
+            while (true)
+            {
+                try
+                {
+                    db.Write(WriteOptions.Default, batch);
+                    break;
+                }
+                catch (LevelDBException ex)
+                {
+                    if (++retry >= 4) throw;
+                    File.AppendAllText("leveldb.log", ex.Message + "\r\n");
+                }
+            }
             current_block_height = block.Height;
         }
 

src/AntShares/Wallets/Wallet.cs

@@ -197,6 +197,7 @@ public bool ChangePassword(string password_old, string password_new)
             {
                 try
                 {
+                    SaveStoredData("PasswordHash", passwordKey.Sha256());
                     SaveStoredData("MasterKey", masterKey.AesEncrypt(passwordKey, iv));
                     return true;
                 }