| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.dubbo.remoting.telnet.codec; |
| |
| import org.apache.dubbo.common.URL; |
| import org.apache.dubbo.common.logger.ErrorTypeAwareLogger; |
| import org.apache.dubbo.common.logger.LoggerFactory; |
| import org.apache.dubbo.common.utils.CollectionUtils; |
| import org.apache.dubbo.common.utils.StringUtils; |
| import org.apache.dubbo.remoting.Channel; |
| import org.apache.dubbo.remoting.RemotingException; |
| import org.apache.dubbo.remoting.buffer.ChannelBuffer; |
| import org.apache.dubbo.remoting.transport.codec.TransportCodec; |
| |
| import java.io.IOException; |
| import java.io.UnsupportedEncodingException; |
| import java.nio.charset.Charset; |
| import java.util.Arrays; |
| import java.util.LinkedList; |
| import java.util.List; |
| |
| import static org.apache.dubbo.common.constants.LoggerCodeConstants.TRANSPORT_UNSUPPORTED_CHARSET; |
| import static org.apache.dubbo.remoting.Constants.CHARSET_KEY; |
| import static org.apache.dubbo.remoting.Constants.DEFAULT_CHARSET; |
| |
| /** |
| * TelnetCodec |
| */ |
| public class TelnetCodec extends TransportCodec { |
| |
| private static final ErrorTypeAwareLogger logger = LoggerFactory.getErrorTypeAwareLogger(TelnetCodec.class); |
| |
| private static final String HISTORY_LIST_KEY = "telnet.history.list"; |
| |
| private static final String HISTORY_INDEX_KEY = "telnet.history.index"; |
| |
| private static final byte[] UP = new byte[] {27, 91, 65}; |
| |
| private static final byte[] DOWN = new byte[] {27, 91, 66}; |
| |
| private static final List<?> ENTER = |
| Arrays.asList(new byte[] {'\r', '\n'} /* Windows Enter */, new byte[] {'\n'} /* Linux Enter */); |
| |
| private static final List<?> EXIT = Arrays.asList( |
| new byte[] {3} /* Windows Ctrl+C */, |
| new byte[] {-1, -12, -1, -3, 6} /* Linux Ctrl+C */, |
| new byte[] {-1, -19, -1, -3, 6} /* Linux Pause */); |
| |
| private static Charset getCharset(Channel channel) { |
| if (channel != null) { |
| Object attribute = channel.getAttribute(CHARSET_KEY); |
| if (attribute instanceof String) { |
| try { |
| return Charset.forName((String) attribute); |
| } catch (Throwable t) { |
| logger.warn(TRANSPORT_UNSUPPORTED_CHARSET, "", "", t.getMessage(), t); |
| } |
| } else if (attribute instanceof Charset) { |
| return (Charset) attribute; |
| } |
| URL url = channel.getUrl(); |
| if (url != null) { |
| String parameter = url.getParameter(CHARSET_KEY); |
| if (StringUtils.isNotEmpty(parameter)) { |
| try { |
| return Charset.forName(parameter); |
| } catch (Throwable t) { |
| logger.warn(TRANSPORT_UNSUPPORTED_CHARSET, "", "", t.getMessage(), t); |
| } |
| } |
| } |
| } |
| try { |
| return Charset.forName(DEFAULT_CHARSET); |
| } catch (Throwable t) { |
| logger.warn(TRANSPORT_UNSUPPORTED_CHARSET, "", "", t.getMessage(), t); |
| } |
| return Charset.defaultCharset(); |
| } |
| |
| private static String toString(byte[] message, Charset charset) throws UnsupportedEncodingException { |
| byte[] copy = new byte[message.length]; |
| int index = 0; |
| for (int i = 0; i < message.length; i++) { |
| byte b = message[i]; |
| if (b == '\b') { // backspace |
| if (index > 0) { |
| index--; |
| } |
| if (i > 2 && message[i - 2] < 0) { // double byte char |
| if (index > 0) { |
| index--; |
| } |
| } |
| } else if (b == 27) { // escape |
| if (i < message.length - 4 && message[i + 4] == 126) { |
| i = i + 4; |
| } else if (i < message.length - 3 && message[i + 3] == 126) { |
| i = i + 3; |
| } else if (i < message.length - 2) { |
| i = i + 2; |
| } |
| } else if (b == -1 |
| && i < message.length - 2 |
| && (message[i + 1] == -3 || message[i + 1] == -5)) { // handshake |
| i = i + 2; |
| } else { |
| copy[index++] = message[i]; |
| } |
| } |
| if (index == 0) { |
| return ""; |
| } |
| return new String(copy, 0, index, charset.name()).trim(); |
| } |
| |
| private static boolean isEquals(byte[] message, byte[] command) throws IOException { |
| return message.length == command.length && endsWith(message, command); |
| } |
| |
| private static boolean endsWith(byte[] message, byte[] command) throws IOException { |
| if (message.length < command.length) { |
| return false; |
| } |
| int offset = message.length - command.length; |
| for (int i = command.length - 1; i >= 0; i--) { |
| if (message[offset + i] != command[i]) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| @Override |
| public void encode(Channel channel, ChannelBuffer buffer, Object message) throws IOException { |
| if (message instanceof String) { |
| if (isClientSide(channel)) { |
| message = message + "\r\n"; |
| } |
| byte[] msgData = ((String) message).getBytes(getCharset(channel).name()); |
| buffer.writeBytes(msgData); |
| } else { |
| super.encode(channel, buffer, message); |
| } |
| } |
| |
| @Override |
| public Object decode(Channel channel, ChannelBuffer buffer) throws IOException { |
| int readable = buffer.readableBytes(); |
| byte[] message = new byte[readable]; |
| buffer.readBytes(message); |
| return decode(channel, buffer, readable, message); |
| } |
| |
| @SuppressWarnings("unchecked") |
| protected Object decode(Channel channel, ChannelBuffer buffer, int readable, byte[] message) throws IOException { |
| if (isClientSide(channel)) { |
| return toString(message, getCharset(channel)); |
| } |
| checkPayload(channel, readable); |
| if (message == null || message.length == 0) { |
| return DecodeResult.NEED_MORE_INPUT; |
| } |
| |
| if (message[message.length - 1] == '\b') { // Windows backspace echo |
| try { |
| boolean isDoubleChar = message.length >= 3 && message[message.length - 3] < 0; // double byte char |
| channel.send(new String( |
| isDoubleChar ? new byte[] {32, 32, 8, 8} : new byte[] {32, 8}, |
| getCharset(channel).name())); |
| } catch (RemotingException e) { |
| throw new IOException(StringUtils.toString(e)); |
| } |
| return DecodeResult.NEED_MORE_INPUT; |
| } |
| |
| for (Object command : EXIT) { |
| if (isEquals(message, (byte[]) command)) { |
| if (logger.isInfoEnabled()) { |
| logger.info(new Exception( |
| "Close channel " + channel + " on exit command: " + Arrays.toString((byte[]) command))); |
| } |
| channel.close(); |
| return null; |
| } |
| } |
| |
| boolean up = endsWith(message, UP); |
| boolean down = endsWith(message, DOWN); |
| if (up || down) { |
| LinkedList<String> history = (LinkedList<String>) channel.getAttribute(HISTORY_LIST_KEY); |
| if (CollectionUtils.isEmpty(history)) { |
| return DecodeResult.NEED_MORE_INPUT; |
| } |
| Integer index = (Integer) channel.getAttribute(HISTORY_INDEX_KEY); |
| Integer old = index; |
| if (index == null) { |
| index = history.size() - 1; |
| } else { |
| if (up) { |
| index = index - 1; |
| if (index < 0) { |
| index = history.size() - 1; |
| } |
| } else { |
| index = index + 1; |
| if (index > history.size() - 1) { |
| index = 0; |
| } |
| } |
| } |
| if (old == null || !old.equals(index)) { |
| channel.setAttribute(HISTORY_INDEX_KEY, index); |
| String value = history.get(index); |
| if (old != null && old >= 0 && old < history.size()) { |
| String ov = history.get(old); |
| StringBuilder buf = new StringBuilder(); |
| for (int i = 0; i < ov.length(); i++) { |
| buf.append('\b'); |
| } |
| for (int i = 0; i < ov.length(); i++) { |
| buf.append(' '); |
| } |
| for (int i = 0; i < ov.length(); i++) { |
| buf.append('\b'); |
| } |
| value = buf + value; |
| } |
| try { |
| channel.send(value); |
| } catch (RemotingException e) { |
| throw new IOException(StringUtils.toString(e)); |
| } |
| } |
| return DecodeResult.NEED_MORE_INPUT; |
| } |
| for (Object command : EXIT) { |
| if (isEquals(message, (byte[]) command)) { |
| if (logger.isInfoEnabled()) { |
| logger.info(new Exception("Close channel " + channel + " on exit command " + command)); |
| } |
| channel.close(); |
| return null; |
| } |
| } |
| byte[] enter = null; |
| for (Object command : ENTER) { |
| if (endsWith(message, (byte[]) command)) { |
| enter = (byte[]) command; |
| break; |
| } |
| } |
| if (enter == null) { |
| return DecodeResult.NEED_MORE_INPUT; |
| } |
| LinkedList<String> history = (LinkedList<String>) channel.getAttribute(HISTORY_LIST_KEY); |
| Integer index = (Integer) channel.getAttribute(HISTORY_INDEX_KEY); |
| channel.removeAttribute(HISTORY_INDEX_KEY); |
| if (CollectionUtils.isNotEmpty(history) && index != null && index >= 0 && index < history.size()) { |
| String value = history.get(index); |
| if (value != null) { |
| byte[] b1 = value.getBytes(); |
| byte[] b2 = new byte[b1.length + message.length]; |
| System.arraycopy(b1, 0, b2, 0, b1.length); |
| System.arraycopy(message, 0, b2, b1.length, message.length); |
| message = b2; |
| } |
| } |
| String result = toString(message, getCharset(channel)); |
| if (result.trim().length() > 0) { |
| if (history == null) { |
| history = new LinkedList<>(); |
| channel.setAttribute(HISTORY_LIST_KEY, history); |
| } |
| if (history.isEmpty()) { |
| history.addLast(result); |
| } else if (!result.equals(history.getLast())) { |
| history.remove(result); |
| history.addLast(result); |
| if (history.size() > 10) { |
| history.removeFirst(); |
| } |
| } |
| } |
| return result; |
| } |
| } |