src/main/java/net/pterodactylus/fcp/FcpConnectionHandler.java

   1 /*
   2  * jFCPlib - FcpConnectionHandler.java - Copyright © 2008 David Roden
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17  */
  18
  19 package net.pterodactylus.fcp;
  20
  21 import java.io.EOFException;
  22 import java.io.IOException;
  23 import java.io.InputStream;
  24 import java.nio.ByteBuffer;
  25 import java.nio.charset.Charset;
  26 import java.util.logging.Level;
  27 import java.util.logging.Logger;
  28
  29 /**
  30  * Handles an FCP connection to a node.
  31  *
  32  * @author David ‘Bombe’ Roden &lt;bombe@freenetproject.org&gt;
  33  */
  34 class FcpConnectionHandler implements Runnable {
  35
  36         /** The logger. */
  37         private static final Logger logger = Logger.getLogger(FcpConnectionHandler.class.getName());
  38
  39         /** The underlying connection. */
  40         private final FcpConnection fcpConnection;
  41
  42         /** The input stream from the node. */
  43         private final InputStream remoteInputStream;
  44
  45         /** Whether to stop the connection handler. */
  46         private boolean shouldStop;
  47
  48         /** Whether the next read line feed should be ignored. */
  49         private boolean ignoreNextLinefeed;
  50
  51         /**
  52          * Creates a new connection handler that operates on the given connection
  53          * and input stream.
  54          *
  55          * @param fcpConnection
  56          *            The underlying FCP connection
  57          * @param remoteInputStream
  58          *            The input stream from the node
  59          */
  60         public FcpConnectionHandler(FcpConnection fcpConnection, InputStream remoteInputStream) {
  61                 this.fcpConnection = fcpConnection;
  62                 this.remoteInputStream = remoteInputStream;
  63         }
  64
  65         /**
  66          * {@inheritDoc}
  67          */
  68         @Override
  69         public void run() {
  70                 FcpMessage fcpMessage = null;
  71                 Throwable throwable = null;
  72                 while (true) {
  73                         synchronized (this) {
  74                                 if (shouldStop) {
  75                                         break;
  76                                 }
  77                         }
  78                         try {
  79                                 String line = readLine();
  80                                 logger.log(Level.FINEST, String.format("read line: %1$s", line));
  81                                 if (line == null) {
  82                                         throwable = new EOFException();
  83                                         break;
  84                                 }
  85                                 if (line.length() == 0) {
  86                                         continue;
  87                                 }
  88                                 line = line.trim();
  89                                 if (fcpMessage == null) {
  90                                         fcpMessage = new FcpMessage(line);
  91                                         continue;
  92                                 }
  93                                 if ("EndMessage".equalsIgnoreCase(line) || "Data".equalsIgnoreCase(line)) {
  94                                         fcpConnection.handleMessage(fcpMessage);
  95                                         fcpMessage = null;
  96                                 }
  97                                 int equalSign = line.indexOf('=');
  98                                 if (equalSign == -1) {
  99                                         /* something's fishy! */
 100                                         continue;
 101                                 }
 102                                 String field = line.substring(0, equalSign);
 103                                 String value = line.substring(equalSign + 1);
 104                                 assert fcpMessage != null: "fcp message is null";
 105                                 fcpMessage.setField(field, value);
 106                         } catch (IOException ioe1) {
 107                                 throwable = ioe1;
 108                                 break;
 109                         }
 110                 }
 111                 fcpConnection.handleDisconnect(throwable);
 112         }
 113
 114         /**
 115          * Stops the connection handler.
 116          */
 117         public void stop() {
 118                 synchronized (this) {
 119                         shouldStop = true;
 120                 }
 121         }
 122
 123         //
 124         // PRIVATE METHODS
 125         //
 126
 127         /**
 128          * Reads bytes from {@link #remoteInputStream} until ‘\r’ or ‘\n’ are
 129          * encountered and decodes the read bytes using UTF-8.
 130          *
 131          * @return The decoded line
 132          * @throws IOException
 133          *             if an I/O error occurs
 134          */
 135         private String readLine() throws IOException {
 136                 byte[] readBytes = new byte[512];
 137                 int readIndex = 0;
 138                 while (true) {
 139                         int nextByte = remoteInputStream.read();
 140                         if (nextByte == -1) {
 141                                 if (readIndex == 0) {
 142                                         return null;
 143                                 }
 144                                 break;
 145                         }
 146                         if (nextByte == 10) {
 147                                 if (!ignoreNextLinefeed) {
 148                                         break;
 149                                 }
 150                         }
 151                         ignoreNextLinefeed = false;
 152                         if (nextByte == 13) {
 153                                 ignoreNextLinefeed = true;
 154                                 break;
 155                         }
 156                         if (readIndex == readBytes.length) {
 157                                 /* recopy & enlarge array */
 158                                 byte[] newReadBytes = new byte[readBytes.length * 2];
 159                                 System.arraycopy(readBytes, 0, newReadBytes, 0, readBytes.length);
 160                                 readBytes = newReadBytes;
 161                         }
 162                         readBytes[readIndex++] = (byte) nextByte;
 163                 }
 164                 ByteBuffer byteBuffer = ByteBuffer.wrap(readBytes, 0, readIndex);
 165                 return Charset.forName("UTF-8").decode(byteBuffer).toString();
 166         }
 167
 168 }