mcs/class/System/System.Net/WebConnectionStream.cs

   1 //
   2 // System.Net.WebConnectionStream
   3 //
   4 // Authors:
   5 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   6 //
   7 // (C) 2003 Ximian, Inc (http://www.ximian.com)
   8 // (C) 2004 Novell, Inc (http://www.novell.com)
   9 //
  10
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System.IO;
  33 using System.Text;
  34 using System.Threading;
  35
  36 namespace System.Net
  37 {
  38         class WebConnectionStream : Stream
  39         {
  40                 static byte [] crlf = new byte [] { 13, 10 };
  41                 bool isRead;
  42                 WebConnection cnc;
  43                 HttpWebRequest request;
  44                 byte [] readBuffer;
  45                 int readBufferOffset;
  46                 int readBufferSize;
  47                 int contentLength;
  48                 int totalRead;
  49                 long totalWritten;
  50                 bool nextReadCalled;
  51                 int pendingReads;
  52                 int pendingWrites;
  53                 ManualResetEvent pending;
  54                 bool allowBuffering;
  55                 bool sendChunked;
  56                 MemoryStream writeBuffer;
  57                 bool requestWritten;
  58                 byte [] headers;
  59                 bool disposed;
  60                 bool headersSent;
  61                 object locker = new object ();
  62                 bool initRead;
  63                 bool read_eof;
  64                 bool complete_request_written;
  65                 int read_timeout;
  66                 int write_timeout;
  67
  68                 public WebConnectionStream (WebConnection cnc)
  69                 {
  70                         isRead = true;
  71                         pending = new ManualResetEvent (true);
  72                         this.request = cnc.Data.request;
  73                         read_timeout = request.ReadWriteTimeout;
  74                         write_timeout = read_timeout;
  75                         this.cnc = cnc;
  76                         string contentType = cnc.Data.Headers ["Transfer-Encoding"];
  77                         bool chunkedRead = (contentType != null && contentType.ToLower ().IndexOf ("chunked") != -1);
  78                         string clength = cnc.Data.Headers ["Content-Length"];
  79                         if (!chunkedRead && clength != null && clength != "") {
  80                                 try {
  81                                         contentLength = Int32.Parse (clength);
  82                                         if (contentLength == 0 && !IsNtlmAuth ()) {
  83                                                 ReadAll ();
  84                                         }
  85                                 } catch {
  86                                         contentLength = Int32.MaxValue;
  87                                 }
  88                         } else {
  89                                 contentLength = Int32.MaxValue;
  90                         }
  91                 }
  92
  93                 public WebConnectionStream (WebConnection cnc, HttpWebRequest request)
  94                 {
  95                         read_timeout = request.ReadWriteTimeout;
  96                         write_timeout = read_timeout;
  97                         isRead = false;
  98                         this.cnc = cnc;
  99                         this.request = request;
 100                         allowBuffering = request.InternalAllowBuffering;
 101                         sendChunked = request.SendChunked;
 102                         if (sendChunked)
 103                                 pending = new ManualResetEvent (true);
 104                         else if (allowBuffering)
 105                                 writeBuffer = new MemoryStream ();
 106                 }
 107
 108                 bool IsNtlmAuth ()
 109                 {
 110                         bool isProxy = (request.Proxy != null && !request.Proxy.IsBypassed (request.Address));
 111                         string header_name = (isProxy) ? "Proxy-Authenticate" : "WWW-Authenticate";
 112                         string authHeader = cnc.Data.Headers [header_name];
 113                         return (authHeader != null && authHeader.IndexOf ("NTLM") != -1);
 114                 }
 115
 116                 internal void CheckResponseInBuffer ()
 117                 {
 118                         if (contentLength > 0 && (readBufferSize - readBufferOffset) >= contentLength) {
 119                                 if (!IsNtlmAuth ())
 120                                         ReadAll ();
 121                         }
 122                 }
 123
 124                 internal HttpWebRequest Request {
 125                         get { return request; }
 126                 }
 127
 128                 internal WebConnection Connection {
 129                         get { return cnc; }
 130                 }
 131 #if NET_2_0
 132                 public override bool CanTimeout {
 133                         get { return true; }
 134                 }
 135 #endif
 136
 137 #if NET_2_0
 138                 public override
 139 #endif
 140                 int ReadTimeout {
 141                         get {
 142                                 return read_timeout;
 143                         }
 144
 145                         set {
 146                                 if (value < -1)
 147                                         throw new ArgumentOutOfRangeException ("value");
 148                                 read_timeout = value;
 149                         }
 150                 }
 151
 152 #if NET_2_0
 153                 public override
 154 #endif
 155                 int WriteTimeout {
 156                         get {
 157                                 return write_timeout;
 158                         }
 159
 160                         set {
 161                                 if (value < -1)
 162                                         throw new ArgumentOutOfRangeException ("value");
 163                                 write_timeout = value;
 164                         }
 165                 }
 166
 167                 internal bool CompleteRequestWritten {
 168                         get { return complete_request_written; }
 169                 }
 170
 171                 internal bool SendChunked {
 172                         set { sendChunked = value; }
 173                 }
 174
 175                 internal byte [] ReadBuffer {
 176                         set { readBuffer = value; }
 177                 }
 178
 179                 internal int ReadBufferOffset {
 180                         set { readBufferOffset = value;}
 181                 }
 182
 183                 internal int ReadBufferSize {
 184                         set { readBufferSize = value; }
 185                 }
 186
 187                 internal byte[] WriteBuffer {
 188                         get { return writeBuffer.GetBuffer (); }
 189                 }
 190
 191                 internal int WriteBufferLength {
 192                         get { return writeBuffer != null ? (int) writeBuffer.Length : (-1); }
 193                 }
 194
 195                 internal void ForceCompletion ()
 196                 {
 197                         if (!nextReadCalled) {
 198                                 if (contentLength == Int32.MaxValue)
 199                                         contentLength = 0;
 200                                 nextReadCalled = true;
 201                                 cnc.NextRead ();
 202                         }
 203                 }
 204
 205                 internal void CheckComplete ()
 206                 {
 207                         bool nrc = nextReadCalled;
 208                         if (!nrc && readBufferSize - readBufferOffset == contentLength) {
 209                                 nextReadCalled = true;
 210                                 cnc.NextRead ();
 211                         }
 212                 }
 213
 214                 internal void ReadAll ()
 215                 {
 216                         if (!isRead || read_eof || totalRead >= contentLength || nextReadCalled) {
 217                                 if (isRead && !nextReadCalled) {
 218                                         nextReadCalled = true;
 219                                         cnc.NextRead ();
 220                                 }
 221                                 return;
 222                         }
 223
 224                         pending.WaitOne ();
 225                         lock (locker) {
 226                                 if (totalRead >= contentLength)
 227                                         return;
 228
 229                                 byte [] b = null;
 230                                 int diff = readBufferSize - readBufferOffset;
 231                                 int new_size;
 232
 233                                 if (contentLength == Int32.MaxValue) {
 234                                         MemoryStream ms = new MemoryStream ();
 235                                         byte [] buffer = null;
 236                                         if (readBuffer != null && diff > 0) {
 237                                                 ms.Write (readBuffer, readBufferOffset, diff);
 238                                                 if (readBufferSize >= 8192)
 239                                                         buffer = readBuffer;
 240                                         }
 241
 242                                         if (buffer == null)
 243                                                 buffer = new byte [8192];
 244
 245                                         int read;
 246                                         while ((read = cnc.Read (request, buffer, 0, buffer.Length)) != 0)
 247                                                 ms.Write (buffer, 0, read);
 248
 249                                         b = ms.GetBuffer ();
 250                                         new_size = (int) ms.Length;
 251                                         contentLength = new_size;
 252                                 } else {
 253                                         new_size = contentLength - totalRead;
 254                                         b = new byte [new_size];
 255                                         if (readBuffer != null && diff > 0) {
 256                                                 if (diff > new_size)
 257                                                         diff = new_size;
 258
 259                                                 Buffer.BlockCopy (readBuffer, readBufferOffset, b, 0, diff);
 260                                         }
 261
 262                                         int remaining = new_size - diff;
 263                                         int r = -1;
 264                                         while (remaining > 0 && r != 0) {
 265                                                 r = cnc.Read (request, b, diff, remaining);
 266                                                 remaining -= r;
 267                                                 diff += r;
 268                                         }
 269                                 }
 270
 271                                 readBuffer = b;
 272                                 readBufferOffset = 0;
 273                                 readBufferSize = new_size;
 274                                 totalRead = 0;
 275                                 nextReadCalled = true;
 276                         }
 277
 278                         cnc.NextRead ();
 279                 }
 280
 281                 void WriteCallbackWrapper (IAsyncResult r)
 282                 {
 283                         WebAsyncResult result = r as WebAsyncResult;
 284                         if (result != null && result.AsyncWriteAll)
 285                                 return;
 286
 287                         if (r.AsyncState != null) {
 288                                 result = (WebAsyncResult) r.AsyncState;
 289                                 result.InnerAsyncResult = r;
 290                                 result.DoCallback ();
 291                         } else {
 292                                 EndWrite (r);
 293                         }
 294                 }
 295
 296                 void ReadCallbackWrapper (IAsyncResult r)
 297                 {
 298                         WebAsyncResult result;
 299                         if (r.AsyncState != null) {
 300                                 result = (WebAsyncResult) r.AsyncState;
 301                                 result.InnerAsyncResult = r;
 302                                 result.DoCallback ();
 303                         } else {
 304                                 EndRead (r);
 305                         }
 306                 }
 307
 308                 public override int Read (byte [] buffer, int offset, int size)
 309                 {
 310                         if (!isRead)
 311                                 throw new NotSupportedException ("this stream does not allow reading");
 312
 313                         if (totalRead >= contentLength)
 314                                 return 0;
 315
 316                         AsyncCallback cb = new AsyncCallback (ReadCallbackWrapper);
 317                         WebAsyncResult res = (WebAsyncResult) BeginRead (buffer, offset, size, cb, null);
 318                         if (!res.IsCompleted && !res.WaitUntilComplete (ReadTimeout, false)) {
 319                                 nextReadCalled = true;
 320                                 cnc.Close (true);
 321                                 throw new WebException ("The operation has timed out.", WebExceptionStatus.Timeout);
 322                         }
 323
 324                         return EndRead (res);
 325                 }
 326
 327                 public override IAsyncResult BeginRead (byte [] buffer, int offset, int size,
 328                                                         AsyncCallback cb, object state)
 329                 {
 330                         if (!isRead)
 331                                 throw new NotSupportedException ("this stream does not allow reading");
 332
 333                         if (buffer == null)
 334                                 throw new ArgumentNullException ("buffer");
 335
 336                         int length = buffer.Length;
 337                         if (size < 0 || offset < 0 || length < offset || length - offset < size)
 338                                 throw new ArgumentOutOfRangeException ();
 339
 340                         lock (locker) {
 341                                 pendingReads++;
 342                                 pending.Reset ();
 343                         }
 344
 345                         WebAsyncResult result = new WebAsyncResult (cb, state, buffer, offset, size);
 346                         if (totalRead >= contentLength) {
 347                                 result.SetCompleted (true, -1);
 348                                 result.DoCallback ();
 349                                 return result;
 350                         }
 351
 352                         int remaining = readBufferSize - readBufferOffset;
 353                         if (remaining > 0) {
 354                                 int copy = (remaining > size) ? size : remaining;
 355                                 Buffer.BlockCopy (readBuffer, readBufferOffset, buffer, offset, copy);
 356                                 readBufferOffset += copy;
 357                                 offset += copy;
 358                                 size -= copy;
 359                                 totalRead += copy;
 360                                 if (size == 0 || totalRead >= contentLength) {
 361                                         result.SetCompleted (true, copy);
 362                                         result.DoCallback ();
 363                                         return result;
 364                                 }
 365                                 result.NBytes = copy;
 366                         }
 367
 368                         if (cb != null)
 369                                 cb = new AsyncCallback (ReadCallbackWrapper);
 370
 371                         if (contentLength != Int32.MaxValue && contentLength - totalRead < size)
 372                                 size = contentLength - totalRead;
 373
 374                         if (!read_eof) {
 375                                 result.InnerAsyncResult = cnc.BeginRead (request, buffer, offset, size, cb, result);
 376                         } else {
 377                                 result.SetCompleted (true, result.NBytes);
 378                                 result.DoCallback ();
 379                         }
 380                         return result;
 381                 }
 382
 383                 public override int EndRead (IAsyncResult r)
 384                 {
 385                         WebAsyncResult result = (WebAsyncResult) r;
 386                         if (result.EndCalled) {
 387                                 int xx = result.NBytes;
 388                                 return (xx >= 0) ? xx : 0;
 389                         }
 390
 391                         result.EndCalled = true;
 392
 393                         if (!result.IsCompleted) {
 394                                 int nbytes = -1;
 395                                 try {
 396                                         nbytes = cnc.EndRead (request, result);
 397                                 } catch (Exception exc) {
 398                                         lock (locker) {
 399                                                 pendingReads--;
 400                                                 if (pendingReads == 0)
 401                                                         pending.Set ();
 402                                         }
 403
 404                                         nextReadCalled = true;
 405                                         cnc.Close (true);
 406                                         result.SetCompleted (false, exc);
 407                                         throw;
 408                                 }
 409
 410                                 if (nbytes < 0) {
 411                                         nbytes = 0;
 412                                         read_eof = true;
 413                                 }
 414
 415                                 totalRead += nbytes;
 416                                 result.SetCompleted (false, nbytes + result.NBytes);
 417                                 result.DoCallback ();
 418                                 if (nbytes == 0)
 419                                         contentLength = totalRead;
 420                         }
 421
 422                         lock (locker) {
 423                                 pendingReads--;
 424                                 if (pendingReads == 0)
 425                                         pending.Set ();
 426                         }
 427
 428                         if (totalRead >= contentLength && !nextReadCalled)
 429                                 ReadAll ();
 430
 431                         int nb = result.NBytes;
 432                         return (nb >= 0) ? nb : 0;
 433                 }
 434
 435                 void WriteRequestAsyncCB (IAsyncResult r)
 436                 {
 437                         WebAsyncResult result = (WebAsyncResult) r.AsyncState;
 438                         try {
 439                                 cnc.EndWrite2 (request, r);
 440                                 result.SetCompleted (false, 0);
 441                                 if (!initRead) {
 442                                         initRead = true;
 443                                         WebConnection.InitRead (cnc);
 444                                 }
 445                         } catch (Exception e) {
 446                                 KillBuffer ();
 447                                 nextReadCalled = true;
 448                                 cnc.Close (true);
 449                                 if (e is System.Net.Sockets.SocketException)
 450                                         e = new IOException ("Error writing request", e);
 451                                 result.SetCompleted (false, e);
 452                         }
 453                         complete_request_written = true;
 454                         result.DoCallback ();
 455                 }
 456
 457                 public override IAsyncResult BeginWrite (byte [] buffer, int offset, int size,
 458                                                         AsyncCallback cb, object state)
 459                 {
 460                         if (request.Aborted)
 461                                 throw new WebException ("The request was canceled.", null, WebExceptionStatus.RequestCanceled);
 462
 463                         if (isRead)
 464                                 throw new NotSupportedException ("this stream does not allow writing");
 465
 466                         if (buffer == null)
 467                                 throw new ArgumentNullException ("buffer");
 468
 469                         int length = buffer.Length;
 470                         if (size < 0 || offset < 0 || length < offset || length - offset < size)
 471                                 throw new ArgumentOutOfRangeException ();
 472
 473                         if (sendChunked) {
 474                                 lock (locker) {
 475                                         pendingWrites++;
 476                                         pending.Reset ();
 477                                 }
 478                         }
 479
 480                         WebAsyncResult result = new WebAsyncResult (cb, state);
 481                         if (!sendChunked)
 482                                 CheckWriteOverflow (request.ContentLength, totalWritten, size);
 483                         if (allowBuffering && !sendChunked) {
 484                                 if (writeBuffer == null)
 485                                         writeBuffer = new MemoryStream ();
 486                                 writeBuffer.Write (buffer, offset, size);
 487                                 totalWritten += size;
 488                                 if (request.ContentLength > 0 && totalWritten == request.ContentLength) {
 489                                         try {
 490                                                 result.AsyncWriteAll = true;
 491                                                 result.InnerAsyncResult = WriteRequestAsync (new AsyncCallback (WriteRequestAsyncCB), result);
 492                                                 if (result.InnerAsyncResult == null) {
 493                                                         if (!result.IsCompleted)
 494                                                                 result.SetCompleted (true, 0);
 495                                                         result.DoCallback ();
 496                                                 }
 497                                         } catch (Exception exc) {
 498                                                 result.SetCompleted (true, exc);
 499                                                 result.DoCallback ();
 500                                         }
 501                                 } else {
 502                                         result.SetCompleted (true, 0);
 503                                         result.DoCallback ();
 504                                 }
 505                                 return result;
 506                         }
 507
 508                         AsyncCallback callback = null;
 509                         if (cb != null)
 510                                 callback = new AsyncCallback (WriteCallbackWrapper);
 511
 512                         if (sendChunked) {
 513                                 WriteRequest ();
 514
 515                                 string cSize = String.Format ("{0:X}\r\n", size);
 516                                 byte [] head = Encoding.ASCII.GetBytes (cSize);
 517                                 int chunkSize = 2 + size + head.Length;
 518                                 byte [] newBuffer = new byte [chunkSize];
 519                                 Buffer.BlockCopy (head, 0, newBuffer, 0, head.Length);
 520                                 Buffer.BlockCopy (buffer, offset, newBuffer, head.Length, size);
 521                                 Buffer.BlockCopy (crlf, 0, newBuffer, head.Length + size, crlf.Length);
 522
 523                                 buffer = newBuffer;
 524                                 offset = 0;
 525                                 size = chunkSize;
 526                         }
 527
 528                         result.InnerAsyncResult = cnc.BeginWrite (request, buffer, offset, size, callback, result);
 529                         totalWritten += size;
 530                         return result;
 531                 }
 532
 533                 void CheckWriteOverflow (long contentLength, long totalWritten, long size)
 534                 {
 535                         if (contentLength == -1)
 536                                 return;
 537
 538                         long avail = contentLength - totalWritten;
 539                         if (size > avail) {
 540                                 KillBuffer ();
 541                                 nextReadCalled = true;
 542                                 cnc.Close (true);
 543                                 throw new ProtocolViolationException (
 544                                         "The number of bytes to be written is greater than " +
 545                                         "the specified ContentLength.");
 546                         }
 547                 }
 548
 549                 public override void EndWrite (IAsyncResult r)
 550                 {
 551                         if (r == null)
 552                                 throw new ArgumentNullException ("r");
 553
 554                         WebAsyncResult result = r as WebAsyncResult;
 555                         if (result == null)
 556                                 throw new ArgumentException ("Invalid IAsyncResult");
 557
 558                         if (result.EndCalled)
 559                                 return;
 560
 561                         result.EndCalled = true;
 562                         if (result.AsyncWriteAll) {
 563                                 result.WaitUntilComplete ();
 564                                 if (result.GotException)
 565                                         throw result.Exception;
 566                                 return;
 567                         }
 568
 569                         if (allowBuffering && !sendChunked)
 570                                 return;
 571
 572                         if (result.GotException)
 573                                 throw result.Exception;
 574
 575                         try {
 576                                 cnc.EndWrite (request, result.InnerAsyncResult);
 577                                 result.SetCompleted (false, 0);
 578                         } catch (Exception e) {
 579                                 result.SetCompleted (false, e);
 580                                 throw;
 581                         } finally {
 582                                 if (sendChunked) {
 583                                         lock (locker) {
 584                                                 pendingWrites--;
 585                                                 if (pendingWrites == 0)
 586                                                         pending.Set ();
 587                                         }
 588                                 }
 589                         }
 590                 }
 591
 592                 public override void Write (byte [] buffer, int offset, int size)
 593                 {
 594                         if (isRead)
 595                                 throw new NotSupportedException ("This stream does not allow writing");
 596
 597                         AsyncCallback cb = new AsyncCallback (WriteCallbackWrapper);
 598                         WebAsyncResult res = (WebAsyncResult) BeginWrite (buffer, offset, size, cb, null);
 599                         if (!res.IsCompleted && !res.WaitUntilComplete (WriteTimeout, false)) {
 600                                 KillBuffer ();
 601                                 nextReadCalled = true;
 602                                 cnc.Close (true);
 603                                 throw new IOException ("Write timed out.");
 604                         }
 605
 606                         EndWrite (res);
 607                 }
 608
 609                 public override void Flush ()
 610                 {
 611                 }
 612
 613                 internal void SetHeaders (byte [] buffer, int offset, int size)
 614                 {
 615                         if (headersSent)
 616                                 return;
 617
 618                         headers = new byte [size];
 619                         Buffer.BlockCopy (buffer, offset, headers, 0, size);
 620                         long cl = request.ContentLength;
 621                         string method = request.Method;
 622                         bool no_writestream = (method == "GET" || method == "CONNECT" || method == "HEAD" ||
 623                                                 method == "TRACE" || method == "DELETE");
 624                         if (sendChunked || cl > -1 || no_writestream) {
 625                                 WriteHeaders ();
 626                                 if (!initRead) {
 627                                         initRead = true;
 628                                         WebConnection.InitRead (cnc);
 629                                 }
 630                                 if (!sendChunked && cl == 0)
 631                                         Close ();
 632                         }
 633                 }
 634
 635                 internal bool RequestWritten {
 636                         get { return requestWritten; }
 637                 }
 638
 639                 IAsyncResult WriteRequestAsync (AsyncCallback cb, object state)
 640                 {
 641                         requestWritten = true;
 642                         byte [] bytes = writeBuffer.GetBuffer ();
 643                         int length = (int) writeBuffer.Length;
 644                         // Headers already written to the stream
 645                         return (length > 0) ? cnc.BeginWrite (request, bytes, 0, length, cb, state) : null;
 646                 }
 647
 648                 void WriteHeaders ()
 649                 {
 650                         if (headersSent)
 651                                 return;
 652
 653                         headersSent = true;
 654                         string err_msg = null;
 655                         if (!cnc.Write (request, headers, 0, headers.Length, ref err_msg))
 656                                 throw new WebException ("Error writing request: " + err_msg, null, WebExceptionStatus.SendFailure, null);
 657                 }
 658
 659                 internal void WriteRequest ()
 660                 {
 661                         if (requestWritten)
 662                                 return;
 663
 664                         if (sendChunked) {
 665                                 requestWritten = true;
 666                                 return;
 667                         }
 668
 669                         if (!allowBuffering || writeBuffer == null)
 670                                 return;
 671
 672                         byte [] bytes = writeBuffer.GetBuffer ();
 673                         int length = (int) writeBuffer.Length;
 674                         if (request.ContentLength != -1 && request.ContentLength < length) {
 675                                 nextReadCalled = true;
 676                                 cnc.Close (true);
 677                                 throw new WebException ("Specified Content-Length is less than the number of bytes to write", null,
 678                                                         WebExceptionStatus.ServerProtocolViolation, null);
 679                         }
 680
 681                         if (!headersSent) {
 682                                 string method = request.Method;
 683                                 bool no_writestream = (method == "GET" || method == "CONNECT" || method == "HEAD" ||
 684                                                         method == "TRACE" || method == "DELETE");
 685                                 if (!no_writestream)
 686                                         request.InternalContentLength = length;
 687                                 request.SendRequestHeaders ();
 688                         }
 689                         WriteHeaders ();
 690                         if (cnc.Data.StatusCode != 0 && cnc.Data.StatusCode != 100)
 691                                 return;
 692
 693                         IAsyncResult result = null;
 694                         if (length > 0)
 695                                 result = cnc.BeginWrite (request, bytes, 0, length, null, null);
 696
 697                         if (!initRead) {
 698                                 initRead = true;
 699                                 WebConnection.InitRead (cnc);
 700                         }
 701
 702                         if (length > 0)
 703                                 complete_request_written = cnc.EndWrite (request, result);
 704                         else
 705                                 complete_request_written = true;
 706                 }
 707
 708                 internal void InternalClose ()
 709                 {
 710                         disposed = true;
 711                 }
 712
 713                 public override void Close ()
 714                 {
 715                         if (sendChunked) {
 716                                 if (disposed)
 717                                         return;
 718                                 disposed = true;
 719                                 pending.WaitOne ();
 720                                 byte [] chunk = Encoding.ASCII.GetBytes ("0\r\n\r\n");
 721                                 string err_msg = null;
 722                                 cnc.Write (request, chunk, 0, chunk.Length, ref err_msg);
 723                                 return;
 724                         }
 725
 726                         if (isRead) {
 727                                 if (!nextReadCalled) {
 728                                         CheckComplete ();
 729                                         // If we have not read all the contents
 730                                         if (!nextReadCalled) {
 731                                                 nextReadCalled = true;
 732                                                 cnc.Close (true);
 733                                         }
 734                                 }
 735                                 return;
 736                         } else if (!allowBuffering) {
 737                                 complete_request_written = true;
 738                                 if (!initRead) {
 739                                         initRead = true;
 740                                         WebConnection.InitRead (cnc);
 741                                 }
 742                                 return;
 743                         }
 744
 745                         if (disposed || requestWritten)
 746                                 return;
 747
 748                         long length = request.ContentLength;
 749
 750                         if (!sendChunked && length != -1 && totalWritten != length) {
 751                                 IOException io = new IOException ("Cannot close the stream until all bytes are written");
 752                                 nextReadCalled = true;
 753                                 cnc.Close (true);
 754                                 throw new WebException ("Request was cancelled.", io, WebExceptionStatus.RequestCanceled);
 755                         }
 756
 757                         WriteRequest ();
 758                         disposed = true;
 759                 }
 760
 761                 internal void KillBuffer ()
 762                 {
 763                         writeBuffer = null;
 764                 }
 765
 766                 public override long Seek (long a, SeekOrigin b)
 767                 {
 768                         throw new NotSupportedException ();
 769                 }
 770
 771                 public override void SetLength (long a)
 772                 {
 773                         throw new NotSupportedException ();
 774                 }
 775
 776                 public override bool CanSeek {
 777                         get { return false; }
 778                 }
 779
 780                 public override bool CanRead {
 781                         get { return isRead; }
 782                 }
 783
 784                 public override bool CanWrite {
 785                         get { return !isRead; }
 786                 }
 787
 788                 public override long Length {
 789                         get { throw new NotSupportedException (); }
 790                 }
 791
 792                 public override long Position {
 793                         get { throw new NotSupportedException (); }
 794                         set { throw new NotSupportedException (); }
 795                 }
 796         }
 797 }
 798