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