System.Data.SqlClient.TdsParser.WriteSessionRecoveryFeatureRequest C# (CSharp) Method

        internal int WriteSessionRecoveryFeatureRequest(SessionData reconnectData, bool write /* if false just calculates the length */)
        {
            int len = 1;
            if (write)
            {
                _physicalStateObj.WriteByte(TdsEnums.FEATUREEXT_SRECOVERY);
            }
            if (reconnectData == null)
            {
                if (write)
                {
                    WriteInt(0, _physicalStateObj);
                }
                len += 4;
            }
            else
            {
                Debug.Assert(reconnectData._unrecoverableStatesCount == 0, "Unrecoverable state count should be 0");
                int initialLength = 0; // sizeof(DWORD) - length itself
                initialLength += 1 + 2 * TdsParserStaticMethods.NullAwareStringLength(reconnectData._initialDatabase);
                initialLength += 1 + 2 * TdsParserStaticMethods.NullAwareStringLength(reconnectData._initialLanguage);
                initialLength += (reconnectData._initialCollation == null) ? 1 : 6;
                for (int i = 0; i < SessionData._maxNumberOfSessionStates; i++)
                {
                    if (reconnectData._initialState[i] != null)
                    {
                        initialLength += 1 /* StateId*/ + StateValueLength(reconnectData._initialState[i].Length);
                    }
                }
                int currentLength = 0; // sizeof(DWORD) - length itself                
                currentLength += 1 + 2 * (reconnectData._initialDatabase == reconnectData._database ? 0 : TdsParserStaticMethods.NullAwareStringLength(reconnectData._database));
                currentLength += 1 + 2 * (reconnectData._initialLanguage == reconnectData._language ? 0 : TdsParserStaticMethods.NullAwareStringLength(reconnectData._language));
                currentLength += (reconnectData._collation != null && !SqlCollation.AreSame(reconnectData._collation, reconnectData._initialCollation)) ? 6 : 1;
                bool[] writeState = new bool[SessionData._maxNumberOfSessionStates];
                for (int i = 0; i < SessionData._maxNumberOfSessionStates; i++)
                {
                    if (reconnectData._delta[i] != null)
                    {
                        Debug.Assert(reconnectData._delta[i]._recoverable, "State should be recoverable");
                        writeState[i] = true;
                        if (reconnectData._initialState[i] != null && reconnectData._initialState[i].Length == reconnectData._delta[i]._dataLength)
                        {
                            writeState[i] = false;
                            for (int j = 0; j < reconnectData._delta[i]._dataLength; j++)
                            {
                                if (reconnectData._initialState[i][j] != reconnectData._delta[i]._data[j])
                                {
                                    writeState[i] = true;
                                    break;
                                }
                            }
                        }
                        if (writeState[i])
                        {
                            currentLength += 1 /* StateId*/ + StateValueLength(reconnectData._delta[i]._dataLength);
                        }
                    }
                }
                if (write)
                {
                    WriteInt(8 + initialLength + currentLength, _physicalStateObj); // length of data w/o total length (initial + current + 2 * sizeof(DWORD))
                    WriteInt(initialLength, _physicalStateObj);
                    WriteIdentifier(reconnectData._initialDatabase, _physicalStateObj);
                    WriteCollation(reconnectData._initialCollation, _physicalStateObj);
                    WriteIdentifier(reconnectData._initialLanguage, _physicalStateObj);
                    for (int i = 0; i < SessionData._maxNumberOfSessionStates; i++)
                    {
                        if (reconnectData._initialState[i] != null)
                        {
                            _physicalStateObj.WriteByte((byte)i);
                            if (reconnectData._initialState[i].Length < 0xFF)
                            {
                                _physicalStateObj.WriteByte((byte)reconnectData._initialState[i].Length);
                            }
                            else
                            {
                                _physicalStateObj.WriteByte(0xFF);
                                WriteInt(reconnectData._initialState[i].Length, _physicalStateObj);
                            }
                            _physicalStateObj.WriteByteArray(reconnectData._initialState[i], reconnectData._initialState[i].Length, 0);
                        }
                    }
                    WriteInt(currentLength, _physicalStateObj);
                    WriteIdentifier(reconnectData._database != reconnectData._initialDatabase ? reconnectData._database : null, _physicalStateObj);
                    WriteCollation(SqlCollation.AreSame(reconnectData._initialCollation, reconnectData._collation) ? null : reconnectData._collation, _physicalStateObj);
                    WriteIdentifier(reconnectData._language != reconnectData._initialLanguage ? reconnectData._language : null, _physicalStateObj);
                    for (int i = 0; i < SessionData._maxNumberOfSessionStates; i++)
                    {
                        if (writeState[i])
                        {
                            _physicalStateObj.WriteByte((byte)i);
                            if (reconnectData._delta[i]._dataLength < 0xFF)
                            {
                                _physicalStateObj.WriteByte((byte)reconnectData._delta[i]._dataLength);
                            }
                            else
                            {
                                _physicalStateObj.WriteByte(0xFF);
                                WriteInt(reconnectData._delta[i]._dataLength, _physicalStateObj);
                            }
                            _physicalStateObj.WriteByteArray(reconnectData._delta[i]._data, reconnectData._delta[i]._dataLength, 0);
                        }
                    }
                }
                len += initialLength + currentLength + 12 /* length fields (initial, current, total) */;
            }
            return len;
        }