mcs/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)
  52                 {
  53                         byte[] buffer = new byte[6];
  54
  55                         try {
  56                                 StreamRead (networkStream, buffer, 6);
  57                         } catch {
  58                                 return MessageStatus.Unknown;
  59                         }
  60
  61                         try
  62                         {
  63                                 bool[] isOnTrack = new bool[_msgHeaders.Length];
  64                                 bool atLeastOneOnTrack = true;
  65                                 int i = 0;
  66
  67                                 while (atLeastOneOnTrack)
  68                                 {
  69                                         atLeastOneOnTrack = false;
  70                                         byte c = buffer [i];
  71                                         for (int n = 0; n<_msgHeaders.Length; n++)
  72                                         {
  73                                                 if (i > 0 && !isOnTrack[n]) continue;
  74
  75                                                 isOnTrack[n] = (c == _msgHeaders[n][i]);
  76                                                 if (isOnTrack[n] && (i == _msgHeaders[n].Length-1)) return (MessageStatus) n;
  77                                                 atLeastOneOnTrack = atLeastOneOnTrack || isOnTrack[n];
  78                                         }
  79                                         i++;
  80                                 }
  81                                 return MessageStatus.Unknown;
  82                         }
  83                         catch (IOException)
  84                         {
  85                                 // Stream closed
  86                                 return MessageStatus.CancelSignal;
  87                         }
  88                 }
  89
  90                 static bool StreamRead (Stream networkStream, byte[] buffer, int count)
  91                 {
  92                         int nr = 0;
  93                         do {
  94                                 int pr = networkStream.Read (buffer, nr, count - nr);
  95                                 if (pr == 0)
  96                                         throw new RemotingException ("Connection closed");
  97                                 nr += pr;
  98                         } while (nr < count);
  99                         return true;
 100                 }
 101
 102                 public static void SendMessageStream (Stream networkStream, Stream data, ITransportHeaders requestHeaders, byte[] buffer)
 103                 {
 104                         if (buffer == null) buffer = new byte[DefaultStreamBufferSize];
 105
 106                         // Writes the message start header
 107                         byte[] dotnetHeader = _msgHeaders[(int) MessageStatus.MethodMessage];
 108                         networkStream.Write(dotnetHeader, 0, dotnetHeader.Length);
 109
 110                         // Writes header tag (0x0000 if request stream, 0x0002 if response stream)
 111                         if(requestHeaders[CommonTransportKeys.RequestUri]!=null) buffer [0] = (byte) 0;
 112                         else buffer[0] = (byte) 2;
 113                         buffer [1] = (byte) 0 ;
 114
 115                         // Writes ID
 116                         buffer [2] = (byte) 0;
 117
 118                         // Writes assemblyID????
 119                         buffer [3] = (byte) 0;
 120
 121                         // Writes the length of the stream being sent (not including the headers)
 122                         int num = (int)data.Length;
 123                         buffer [4] = (byte) num;
 124                         buffer [5] = (byte) (num >> 8);
 125                         buffer [6] = (byte) (num >> 16);
 126                         buffer [7] = (byte) (num >> 24);
 127                         networkStream.Write(buffer, 0, 8);
 128
 129                         // Writes the message headers
 130                         SendHeaders (networkStream, requestHeaders, buffer);
 131
 132                         // Writes the stream
 133                         if (data is MemoryStream)
 134                         {
 135                                 // The copy of the stream can be optimized. The internal
 136                                 // buffer of MemoryStream can be used.
 137                                 MemoryStream memStream = (MemoryStream)data;
 138                                 networkStream.Write (memStream.GetBuffer(), 0, (int)memStream.Length);
 139                         }
 140                         else
 141                         {
 142                                 int nread = data.Read (buffer, 0, buffer.Length);
 143                                 while (nread > 0)
 144                                 {
 145                                         networkStream.Write (buffer, 0, nread);
 146                                         nread = data.Read (buffer, 0, buffer.Length);
 147                                 }
 148                         }
 149                 }
 150
 151                 private static void SendHeaders(Stream networkStream, ITransportHeaders requestHeaders, byte[] buffer)
 152                 {
 153                         // Writes the headers as a sequence of strings
 154                         if (networkStream != null)
 155                         {
 156                                 IEnumerator e = requestHeaders.GetEnumerator();
 157                                 while (e.MoveNext())
 158                                 {
 159                                         DictionaryEntry hdr = (DictionaryEntry)e.Current;
 160                                         switch (hdr.Key.ToString())
 161                                         {
 162                                                 case CommonTransportKeys.RequestUri:
 163                                                         buffer[0] = 4; buffer[1] = 0; buffer[2] = 1;
 164                                                         networkStream.Write(buffer, 0, 3);
 165                                                         break;
 166                                                 case "Content-Type":
 167                                                         buffer[0] = 6; buffer[1] = 0; buffer[2] = 1;
 168                                                         networkStream.Write(buffer, 0, 3);
 169                                                         break;
 170                                                 default:
 171                                                         buffer[0] = 1; buffer[1] = 0; buffer[2] = 1;
 172                                                         networkStream.Write(buffer, 0, 3);
 173                                                         SendString (networkStream, hdr.Key.ToString(), buffer);
 174                                                         break;
 175                                         }
 176                                         networkStream.WriteByte (1);
 177                                         SendString (networkStream, hdr.Value.ToString(), buffer);
 178                                 }
 179                         }
 180                         networkStream.WriteByte (0);    // End of headers
 181                         networkStream.WriteByte (0);
 182                 }
 183
 184                 public static ITransportHeaders ReceiveHeaders (Stream networkStream, byte[] buffer)
 185                 {
 186                         StreamRead (networkStream, buffer, 2);
 187
 188                         byte headerType = buffer [0];
 189                         TransportHeaders headers = new TransportHeaders ();
 190
 191                         while (headerType != 0)
 192                         {
 193                                 string key;
 194                                 StreamRead (networkStream, buffer, 1);  // byte 1
 195                                 switch (headerType)
 196                                 {
 197                                         case 4: key = CommonTransportKeys.RequestUri; break;
 198                                         case 6: key = "Content-Type"; break;
 199                                         case 1: key = ReceiveString (networkStream, buffer); break;
 200                                         default: throw new NotSupportedException ("Unknown header code: " + headerType);
 201                                 }
 202                                 StreamRead (networkStream, buffer, 1);  // byte 1
 203                                 headers[key] = ReceiveString (networkStream, buffer);
 204
 205                                 StreamRead (networkStream, buffer, 2);
 206                                 headerType = buffer [0];
 207                         }
 208
 209                         return headers;
 210                 }
 211
 212                 public static Stream ReceiveMessageStream (Stream networkStream, out ITransportHeaders headers, byte[] buffer)
 213                 {
 214                         headers = null;
 215
 216                         if (buffer == null) buffer = new byte[DefaultStreamBufferSize];
 217
 218                         // Reads header tag:  0 -> Stream with headers or 2 -> Response Stream
 219                         // +
 220                         // Gets the length of the data stream
 221                         StreamRead (networkStream, buffer, 8);
 222
 223                         int byteCount = (buffer [4] | (buffer [5] << 8) |
 224                                 (buffer [6] << 16) | (buffer [7] << 24));
 225
 226                         // Reads the headers
 227                         headers = ReceiveHeaders (networkStream, buffer);
 228
 229                         byte[] resultBuffer = new byte[byteCount];
 230                         StreamRead (networkStream, resultBuffer, byteCount);
 231
 232                         return new MemoryStream (resultBuffer);
 233                 }
 234
 235                 private static void SendString (Stream networkStream, string str, byte[] buffer)
 236                 {
 237                         // Allocates a buffer. Use the internal buffer if it is
 238                         // big enough. If not, create a new one.
 239
 240                         int maxBytes = Encoding.UTF8.GetMaxByteCount(str.Length)+4;     //+4 bytes for storing the string length
 241                         if (maxBytes > buffer.Length)
 242                                 buffer = new byte[maxBytes];
 243
 244                         int num = Encoding.UTF8.GetBytes (str, 0, str.Length, buffer, 4);
 245
 246                         // store number of bytes (not number of chars!)
 247
 248                         buffer [0] = (byte) num;
 249                         buffer [1] = (byte) (num >> 8);
 250                         buffer [2] = (byte) (num >> 16);
 251                         buffer [3] = (byte) (num >> 24);
 252
 253                         // Write the string bytes
 254                         networkStream.Write (buffer, 0, num + 4);
 255                 }
 256
 257                 private static string ReceiveString (Stream networkStream, byte[] buffer)
 258                 {
 259                         StreamRead (networkStream, buffer, 4);
 260
 261                         // Reads the number of bytes (not chars!)
 262
 263                         int byteCount = (buffer [0] | (buffer [1] << 8) |
 264                                 (buffer [2] << 16) | (buffer [3] << 24));
 265
 266                         if (byteCount == 0) return string.Empty;
 267
 268                         // Allocates a buffer of the correct size. Use the
 269                         // internal buffer if it is big enough
 270
 271                         if (byteCount > buffer.Length)
 272                                 buffer = new byte[byteCount];
 273
 274                         // Reads the string
 275
 276                         StreamRead (networkStream, buffer, byteCount);
 277                         char[] chars = Encoding.UTF8.GetChars (buffer, 0, byteCount);
 278
 279                         return new string (chars);
 280                 }
 281
 282         }
 283 }