class/System.Runtime.Remoting/System.Runtime.Remoting.Channels.Tcp/TcpMessageIO.cs

   1 // System.Runtime.Remoting.Channels.Tcp.TcpMessageIO.cs
   2 //
   3 // Author: Lluis Sanchez Gual (lluis@ideary.com)
   4 //
   5 // (C) 2002 Lluis Sanchez Gual
   6
   7 //
   8 // Permission is hereby granted, free of charge, to any person obtaining
   9 // a copy of this software and associated documentation files (the
  10 // "Software"), to deal in the Software without restriction, including
  11 // without limitation the rights to use, copy, modify, merge, publish,
  12 // distribute, sublicense, and/or sell copies of the Software, and to
  13 // permit persons to whom the Software is furnished to do so, subject to
  14 // the following conditions:
  15 //
  16 // The above copyright notice and this permission notice shall be
  17 // included in all copies or substantial portions of the Software.
  18 //
  19 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  20 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  21 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  22 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  23 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  24 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  25 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  26 //
  27
  28 using System;
  29 using System.Runtime.Serialization;
  30 using System.Runtime.Serialization.Formatters.Binary;
  31 using System.Collections;
  32 using System.IO;
  33 using System.Text;
  34 using System.Net.Sockets;
  35
  36 namespace System.Runtime.Remoting.Channels.Tcp
  37 {
  38         enum MessageStatus { MethodMessage = 0, CancelSignal = 1, Unknown = 10}
  39
  40         internal class TcpMessageIO
  41         {
  42                 static byte[][] _msgHeaders =
  43                           {
  44                                   new byte[] { (byte)'.', (byte)'N', (byte)'E', (byte)'T', 1, 0 },
  45                                   new byte[] { 255, 255, 255, 255, 255, 255 }
  46                           };
  47
  48                 public static int DefaultStreamBufferSize = 1000;
  49
  50                 // Identifies an incoming message
  51                 public static MessageStatus ReceiveMessageStatus (Stream networkStream, byte[] buffer)
  52                 {
  53                         try {
  54                                 StreamRead (networkStream, buffer, 6);
  55                         } catch (Exception ex) {
  56                                 throw new RemotingException ("Tcp transport error.", ex);
  57                         }
  58
  59                         try
  60                         {
  61                                 bool[] isOnTrack = new bool[_msgHeaders.Length];
  62                                 bool atLeastOneOnTrack = true;
  63                                 int i = 0;
  64
  65                                 while (atLeastOneOnTrack)
  66                                 {
  67                                         atLeastOneOnTrack = false;
  68                                         byte c = buffer [i];
  69                                         for (int n = 0; n<_msgHeaders.Length; n++)
  70                                         {
  71                                                 if (i > 0 && !isOnTrack[n]) continue;
  72
  73                                                 isOnTrack[n] = (c == _msgHeaders[n][i]);
  74                                                 if (isOnTrack[n] && (i == _msgHeaders[n].Length-1)) return (MessageStatus) n;
  75                                                 atLeastOneOnTrack = atLeastOneOnTrack || isOnTrack[n];
  76                                         }
  77                                         i++;
  78                                 }
  79                                 return MessageStatus.Unknown;
  80                         }
  81                         catch (Exception ex) {
  82                                 throw new RemotingException ("Tcp transport error.", ex);
  83                         }
  84                 }
  85
  86                 static bool StreamRead (Stream networkStream, byte[] buffer, int count)
  87                 {
  88                         int nr = 0;
  89                         do {
  90                                 int pr = networkStream.Read (buffer, nr, count - nr);
  91                                 if (pr == 0)
  92                                         throw new RemotingException ("Connection closed");
  93                                 nr += pr;
  94                         } while (nr < count);
  95                         return true;
  96                 }
  97
  98                 public static void SendMessageStream (Stream networkStream, Stream data, ITransportHeaders requestHeaders, byte[] buffer)
  99                 {
 100                         SendMessageStream (networkStream, data, requestHeaders, buffer, false);
 101                 }
 102
 103                 public static void SendMessageStream (Stream networkStream, Stream data, ITransportHeaders requestHeaders, byte[] buffer, bool isOneWay)
 104                 {
 105                         if (buffer == null) buffer = new byte[DefaultStreamBufferSize];
 106
 107                         // Writes the message start header
 108                         byte[] dotnetHeader = _msgHeaders[(int) MessageStatus.MethodMessage];
 109                         networkStream.Write(dotnetHeader, 0, dotnetHeader.Length);
 110
 111                         // Writes the header tag
 112                         // 0x0000 - request stream
 113                         // 0x0001 - OneWay request stream
 114                         // 0x0002 - response stream
 115                         if(requestHeaders[CommonTransportKeys.RequestUri]!=null) {
 116                                 buffer [0] = isOneWay ? (byte) 1 : (byte) 0;
 117                         }
 118                         else {
 119                                 buffer[0] = (byte) 2;
 120                         }
 121                         buffer [1] = (byte) 0 ;
 122
 123                         // Writes ID
 124                         buffer [2] = (byte) 0;
 125
 126                         // Writes assemblyID????
 127                         buffer [3] = (byte) 0;
 128
 129                         // Writes the length of the stream being sent (not including the headers)
 130                         int num = (int)data.Length;
 131                         buffer [4] = (byte) num;
 132                         buffer [5] = (byte) (num >> 8);
 133                         buffer [6] = (byte) (num >> 16);
 134                         buffer [7] = (byte) (num >> 24);
 135                         networkStream.Write(buffer, 0, 8);
 136
 137                         // Writes the message headers
 138                         SendHeaders (networkStream, requestHeaders, buffer);
 139
 140                         if (data.Length == 0)
 141                                 return;
 142
 143                         // Writes the stream
 144                         if (data is MemoryStream)
 145                         {
 146                                 // The copy of the stream can be optimized. The internal
 147                                 // buffer of MemoryStream can be used.
 148                                 MemoryStream memStream = (MemoryStream)data;
 149                                 networkStream.Write (memStream.GetBuffer(), 0, (int)memStream.Length);
 150                         }
 151                         else
 152                         {
 153                                 int nread = data.Read (buffer, 0, buffer.Length);
 154                                 while (nread > 0)
 155                                 {
 156                                         networkStream.Write (buffer, 0, nread);
 157                                         nread = data.Read (buffer, 0, buffer.Length);
 158                                 }
 159                         }
 160                 }
 161
 162                 static byte[] msgUriTransportKey = new byte[] { 4, 0, 1, 1 };
 163                 static byte[] msgContentTypeTransportKey = new byte[] { 6, 0, 1, 1 };
 164                 static byte[] msgDefaultTransportKey = new byte[] { 1, 0, 1 };
 165                 static byte[] msgHeaderTerminator = new byte[] { 0, 0 };
 166
 167                 private static void SendHeaders(Stream networkStream, ITransportHeaders requestHeaders, byte[] buffer)
 168                 {
 169                         // Writes the headers as a sequence of strings
 170                         if (networkStream != null)
 171                         {
 172                                 IEnumerator e = requestHeaders.GetEnumerator();
 173                                 while (e.MoveNext())
 174                                 {
 175                                         DictionaryEntry hdr = (DictionaryEntry)e.Current;
 176                                         switch (hdr.Key.ToString())
 177                                         {
 178                                                 case CommonTransportKeys.RequestUri:
 179                                                         networkStream.Write (msgUriTransportKey, 0, 4);
 180                                                         break;
 181                                                 case "Content-Type":
 182                                                         networkStream.Write (msgContentTypeTransportKey, 0, 4);
 183                                                         break;
 184                                                 default:
 185                                                         networkStream.Write (msgDefaultTransportKey, 0, 3);
 186                                                         SendString (networkStream, hdr.Key.ToString(), buffer);
 187                                                         networkStream.WriteByte (1);
 188                                                         break;
 189                                         }
 190                                         SendString (networkStream, hdr.Value.ToString(), buffer);
 191                                 }
 192                         }
 193                         networkStream.Write (msgHeaderTerminator, 0, 2);        // End of headers
 194                 }
 195
 196                 public static ITransportHeaders ReceiveHeaders (Stream networkStream, byte[] buffer)
 197                 {
 198                         StreamRead (networkStream, buffer, 2);
 199
 200                         byte headerType = buffer [0];
 201                         TransportHeaders headers = new TransportHeaders ();
 202
 203                         while (headerType != 0)
 204                         {
 205                                 string key;
 206                                 StreamRead (networkStream, buffer, 1);  // byte 1
 207                                 switch (headerType)
 208                                 {
 209                                         case 4: key = CommonTransportKeys.RequestUri; break;
 210                                         case 6: key = "Content-Type"; break;
 211                                         case 1: key = ReceiveString (networkStream, buffer); break;
 212                                         default: throw new NotSupportedException ("Unknown header code: " + headerType);
 213                                 }
 214                                 StreamRead (networkStream, buffer, 1);  // byte 1
 215                                 headers[key] = ReceiveString (networkStream, buffer);
 216
 217                                 StreamRead (networkStream, buffer, 2);
 218                                 headerType = buffer [0];
 219                         }
 220
 221                         return headers;
 222                 }
 223
 224                 public static Stream ReceiveMessageStream (Stream networkStream, out ITransportHeaders headers, byte[] buffer)
 225                 {
 226                         headers = null;
 227
 228                         if (buffer == null) buffer = new byte[DefaultStreamBufferSize];
 229
 230                         // Reads header tag:  0 -> Stream with headers or 2 -> Response Stream
 231                         // +
 232                         // Gets the length of the data stream
 233                         StreamRead (networkStream, buffer, 8);
 234
 235                         int byteCount = (buffer [4] | (buffer [5] << 8) |
 236                                 (buffer [6] << 16) | (buffer [7] << 24));
 237
 238                         // Reads the headers
 239                         headers = ReceiveHeaders (networkStream, buffer);
 240
 241                         if (byteCount > 0) {
 242                                 byte[] resultBuffer = new byte[byteCount];
 243                                 StreamRead (networkStream, resultBuffer, byteCount);
 244                                 return new MemoryStream (resultBuffer);
 245                         } else {
 246                                 return new MemoryStream ();
 247                         }
 248                 }
 249
 250                 private static void SendString (Stream networkStream, string str, byte[] buffer)
 251                 {
 252                         // Allocates a buffer. Use the internal buffer if it is
 253                         // big enough. If not, create a new one.
 254
 255                         int maxBytes = Encoding.UTF8.GetMaxByteCount(str.Length)+4;     //+4 bytes for storing the string length
 256                         if (maxBytes > buffer.Length)
 257                                 buffer = new byte[maxBytes];
 258
 259                         int num = Encoding.UTF8.GetBytes (str, 0, str.Length, buffer, 4);
 260
 261                         // store number of bytes (not number of chars!)
 262
 263                         buffer [0] = (byte) num;
 264                         buffer [1] = (byte) (num >> 8);
 265                         buffer [2] = (byte) (num >> 16);
 266                         buffer [3] = (byte) (num >> 24);
 267
 268                         // Write the string bytes
 269                         networkStream.Write (buffer, 0, num + 4);
 270                 }
 271
 272                 private static string ReceiveString (Stream networkStream, byte[] buffer)
 273                 {
 274                         StreamRead (networkStream, buffer, 4);
 275
 276                         // Reads the number of bytes (not chars!)
 277
 278                         int byteCount = (buffer [0] | (buffer [1] << 8) |
 279                                 (buffer [2] << 16) | (buffer [3] << 24));
 280
 281                         if (byteCount == 0) return string.Empty;
 282
 283                         // Allocates a buffer of the correct size. Use the
 284                         // internal buffer if it is big enough
 285
 286                         if (byteCount > buffer.Length)
 287                                 buffer = new byte[byteCount];
 288
 289                         // Reads the string
 290
 291                         StreamRead (networkStream, buffer, byteCount);
 292                         char[] chars = Encoding.UTF8.GetChars (buffer, 0, byteCount);
 293
 294                         return new string (chars);
 295                 }
 296
 297         }
 298 }