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 stream_length; // -1 when CL not present
  48                 int contentLength;
  49                 int totalRead;
  50                 internal long totalWritten;
  51                 bool nextReadCalled;
  52                 int pendingReads;
  53                 int pendingWrites;
  54                 ManualResetEvent pending;
  55                 bool allowBuffering;
  56                 bool sendChunked;
  57                 MemoryStream writeBuffer;
  58                 bool requestWritten;
  59                 byte [] headers;
  60                 bool disposed;
  61                 bool headersSent;
  62                 object locker = new object ();
  63                 bool initRead;
  64                 bool read_eof;
  65                 bool complete_request_written;
  66                 int read_timeout;
  67                 int write_timeout;
  68                 AsyncCallback cb_wrapper; // Calls to ReadCallbackWrapper or WriteCallbacWrapper
  69                 internal bool IgnoreIOErrors;
  70
  71                 public WebConnectionStream (WebConnection cnc, WebConnectionData data)
  72                 {
  73                         if (data == null)
  74                                 throw new InvalidOperationException ("data was not initialized");
  75                         if (data.Headers == null)
  76                                 throw new InvalidOperationException ("data.Headers was not initialized");
  77                         if (data.request == null)
  78                                 throw new InvalidOperationException ("data.request was not initialized");
  79                         isRead = true;
  80                         cb_wrapper = new AsyncCallback (ReadCallbackWrapper);
  81                         pending = new ManualResetEvent (true);
  82                         this.request = data.request;
  83                         read_timeout = request.ReadWriteTimeout;
  84                         write_timeout = read_timeout;
  85                         this.cnc = cnc;
  86                         string contentType = data.Headers ["Transfer-Encoding"];
  87                         bool chunkedRead = (contentType != null && contentType.IndexOf ("chunked", StringComparison.OrdinalIgnoreCase) != -1);
  88                         string clength = data.Headers ["Content-Length"];
  89                         if (!chunkedRead && clength != null && clength != "") {
  90                                 try {
  91                                         contentLength = Int32.Parse (clength);
  92                                         if (contentLength == 0 && !IsNtlmAuth ()) {
  93                                                 ReadAll ();
  94                                         }
  95                                 } catch {
  96                                         contentLength = Int32.MaxValue;
  97                                 }
  98                         } else {
  99                                 contentLength = Int32.MaxValue;
 100                         }
 101
 102                         // Negative numbers?
 103                         if (!Int32.TryParse (clength, out stream_length))
 104                                 stream_length = -1;
 105                 }
 106
 107                 public WebConnectionStream (WebConnection cnc, HttpWebRequest request)
 108                 {
 109                         read_timeout = request.ReadWriteTimeout;
 110                         write_timeout = read_timeout;
 111                         isRead = false;
 112                         cb_wrapper = new AsyncCallback (WriteCallbackWrapper);
 113                         this.cnc = cnc;
 114                         this.request = request;
 115                         allowBuffering = request.InternalAllowBuffering;
 116                         sendChunked = request.SendChunked;
 117                         if (sendChunked)
 118                                 pending = new ManualResetEvent (true);
 119                         else if (allowBuffering)
 120                                 writeBuffer = new MemoryStream ();
 121                 }
 122
 123                 bool IsNtlmAuth ()
 124                 {
 125                         bool isProxy = (request.Proxy != null && !request.Proxy.IsBypassed (request.Address));
 126                         string header_name = (isProxy) ? "Proxy-Authenticate" : "WWW-Authenticate";
 127                         string authHeader = cnc.Data.Headers [header_name];
 128                         return (authHeader != null && authHeader.IndexOf ("NTLM", StringComparison.Ordinal) != -1);
 129                 }
 130
 131                 internal void CheckResponseInBuffer ()
 132                 {
 133                         if (contentLength > 0 && (readBufferSize - readBufferOffset) >= contentLength) {
 134                                 if (!IsNtlmAuth ())
 135                                         ReadAll ();
 136                         }
 137                 }
 138
 139                 internal HttpWebRequest Request {
 140                         get { return request; }
 141                 }
 142
 143                 internal WebConnection Connection {
 144                         get { return cnc; }
 145                 }
 146                 public override bool CanTimeout {
 147                         get { return true; }
 148                 }
 149
 150                 public override int ReadTimeout {
 151                         get {
 152                                 return read_timeout;
 153                         }
 154
 155                         set {
 156                                 if (value < -1)
 157                                         throw new ArgumentOutOfRangeException ("value");
 158                                 read_timeout = value;
 159                         }
 160                 }
 161
 162                 public override int WriteTimeout {
 163                         get {
 164                                 return write_timeout;
 165                         }
 166
 167                         set {
 168                                 if (value < -1)
 169                                         throw new ArgumentOutOfRangeException ("value");
 170                                 write_timeout = value;
 171                         }
 172                 }
 173
 174                 internal bool CompleteRequestWritten {
 175                         get { return complete_request_written; }
 176                 }
 177
 178                 internal bool SendChunked {
 179                         set { sendChunked = value; }
 180                 }
 181
 182                 internal byte [] ReadBuffer {
 183                         set { readBuffer = value; }
 184                 }
 185
 186                 internal int ReadBufferOffset {
 187                         set { readBufferOffset = value;}
 188                 }
 189
 190                 internal int ReadBufferSize {
 191                         set { readBufferSize = value; }
 192                 }
 193
 194                 internal byte[] WriteBuffer {
 195                         get { return writeBuffer.GetBuffer (); }
 196                 }
 197
 198                 internal int WriteBufferLength {
 199                         get { return writeBuffer != null ? (int) writeBuffer.Length : (-1); }
 200                 }
 201
 202                 internal void ForceCompletion ()
 203                 {
 204                         if (!nextReadCalled) {
 205                                 if (contentLength == Int32.MaxValue)
 206                                         contentLength = 0;
 207                                 nextReadCalled = true;
 208                                 cnc.NextRead ();
 209                         }
 210                 }
 211
 212                 internal void CheckComplete ()
 213                 {
 214                         bool nrc = nextReadCalled;
 215                         if (!nrc && readBufferSize - readBufferOffset == contentLength) {
 216                                 nextReadCalled = true;
 217                                 cnc.NextRead ();
 218                         }
 219                 }
 220
 221                 internal void ReadAll ()
 222                 {
 223                         if (!isRead || read_eof || totalRead >= contentLength || nextReadCalled) {
 224                                 if (isRead && !nextReadCalled) {
 225                                         nextReadCalled = true;
 226                                         cnc.NextRead ();
 227                                 }
 228                                 return;
 229                         }
 230
 231                         pending.WaitOne ();
 232                         lock (locker) {
 233                                 if (totalRead >= contentLength)
 234                                         return;
 235
 236                                 byte [] b = null;
 237                                 int diff = readBufferSize - readBufferOffset;
 238                                 int new_size;
 239
 240                                 if (contentLength == Int32.MaxValue) {
 241                                         MemoryStream ms = new MemoryStream ();
 242                                         byte [] buffer = null;
 243                                         if (readBuffer != null && diff > 0) {
 244                                                 ms.Write (readBuffer, readBufferOffset, diff);
 245                                                 if (readBufferSize >= 8192)
 246                                                         buffer = readBuffer;
 247                                         }
 248
 249                                         if (buffer == null)
 250                                                 buffer = new byte [8192];
 251
 252                                         int read;
 253                                         while ((read = cnc.Read (request, buffer, 0, buffer.Length)) != 0)
 254                                                 ms.Write (buffer, 0, read);
 255
 256                                         b = ms.GetBuffer ();
 257                                         new_size = (int) ms.Length;
 258                                         contentLength = new_size;
 259                                 } else {
 260                                         new_size = contentLength - totalRead;
 261                                         b = new byte [new_size];
 262                                         if (readBuffer != null && diff > 0) {
 263                                                 if (diff > new_size)
 264                                                         diff = new_size;
 265
 266                                                 Buffer.BlockCopy (readBuffer, readBufferOffset, b, 0, diff);
 267                                         }
 268
 269                                         int remaining = new_size - diff;
 270                                         int r = -1;
 271                                         while (remaining > 0 && r != 0) {
 272                                                 r = cnc.Read (request, b, diff, remaining);
 273                                                 remaining -= r;
 274                                                 diff += r;
 275                                         }
 276                                 }
 277
 278                                 readBuffer = b;
 279                                 readBufferOffset = 0;
 280                                 readBufferSize = new_size;
 281                                 totalRead = 0;
 282                                 nextReadCalled = true;
 283                         }
 284
 285                         cnc.NextRead ();
 286                 }
 287
 288                 void WriteCallbackWrapper (IAsyncResult r)
 289                 {
 290                         WebAsyncResult result = r as WebAsyncResult;
 291                         if (result != null && result.AsyncWriteAll)
 292                                 return;
 293
 294                         if (r.AsyncState != null) {
 295                                 result = (WebAsyncResult) r.AsyncState;
 296                                 result.InnerAsyncResult = r;
 297                                 result.DoCallback ();
 298                         } else {
 299                                 try {
 300                                         EndWrite (r);
 301                                 } catch {
 302                                 }
 303                         }
 304                 }
 305
 306                 void ReadCallbackWrapper (IAsyncResult r)
 307                 {
 308                         WebAsyncResult result;
 309                         if (r.AsyncState != null) {
 310                                 result = (WebAsyncResult) r.AsyncState;
 311                                 result.InnerAsyncResult = r;
 312                                 result.DoCallback ();
 313                         } else {
 314                                 try {
 315                                         EndRead (r);
 316                                 } catch {
 317                                 }
 318                         }
 319                 }
 320
 321                 public override int Read (byte [] buffer, int offset, int size)
 322                 {
 323                         AsyncCallback cb = cb_wrapper;
 324                         WebAsyncResult res = (WebAsyncResult) BeginRead (buffer, offset, size, cb, null);
 325                         if (!res.IsCompleted && !res.WaitUntilComplete (ReadTimeout, false)) {
 326                                 nextReadCalled = true;
 327                                 cnc.Close (true);
 328                                 throw new WebException ("The operation has timed out.", WebExceptionStatus.Timeout);
 329                         }
 330
 331                         return EndRead (res);
 332                 }
 333
 334                 public override IAsyncResult BeginRead (byte [] buffer, int offset, int size,
 335                                                         AsyncCallback cb, object state)
 336                 {
 337                         if (!isRead)
 338                                 throw new NotSupportedException ("this stream does not allow reading");
 339
 340                         if (buffer == null)
 341                                 throw new ArgumentNullException ("buffer");
 342
 343                         int length = buffer.Length;
 344                         if (offset < 0 || length < offset)
 345                                 throw new ArgumentOutOfRangeException ("offset");
 346                         if (size < 0 || (length - offset) < size)
 347                                 throw new ArgumentOutOfRangeException ("size");
 348
 349                         lock (locker) {
 350                                 pendingReads++;
 351                                 pending.Reset ();
 352                         }
 353
 354                         WebAsyncResult result = new WebAsyncResult (cb, state, buffer, offset, size);
 355                         if (totalRead >= contentLength) {
 356                                 result.SetCompleted (true, -1);
 357                                 result.DoCallback ();
 358                                 return result;
 359                         }
 360
 361                         int remaining = readBufferSize - readBufferOffset;
 362                         if (remaining > 0) {
 363                                 int copy = (remaining > size) ? size : remaining;
 364                                 Buffer.BlockCopy (readBuffer, readBufferOffset, buffer, offset, copy);
 365                                 readBufferOffset += copy;
 366                                 offset += copy;
 367                                 size -= copy;
 368                                 totalRead += copy;
 369                                 if (size == 0 || totalRead >= contentLength) {
 370                                         result.SetCompleted (true, copy);
 371                                         result.DoCallback ();
 372                                         return result;
 373                                 }
 374                                 result.NBytes = copy;
 375                         }
 376
 377                         if (cb != null)
 378                                 cb = cb_wrapper;
 379
 380                         if (contentLength != Int32.MaxValue && contentLength - totalRead < size)
 381                                 size = contentLength - totalRead;
 382
 383                         if (!read_eof) {
 384                                 result.InnerAsyncResult = cnc.BeginRead (request, buffer, offset, size, cb, result);
 385                         } else {
 386                                 result.SetCompleted (true, result.NBytes);
 387                                 result.DoCallback ();
 388                         }
 389                         return result;
 390                 }
 391
 392                 public override int EndRead (IAsyncResult r)
 393                 {
 394                         WebAsyncResult result = (WebAsyncResult) r;
 395                         if (result.EndCalled) {
 396                                 int xx = result.NBytes;
 397                                 return (xx >= 0) ? xx : 0;
 398                         }
 399
 400                         result.EndCalled = true;
 401
 402                         if (!result.IsCompleted) {
 403                                 int nbytes = -1;
 404                                 try {
 405                                         nbytes = cnc.EndRead (request, result);
 406                                 } catch (Exception exc) {
 407                                         lock (locker) {
 408                                                 pendingReads--;
 409                                                 if (pendingReads == 0)
 410                                                         pending.Set ();
 411                                         }
 412
 413                                         nextReadCalled = true;
 414                                         cnc.Close (true);
 415                                         result.SetCompleted (false, exc);
 416                                         result.DoCallback ();
 417                                         throw;
 418                                 }
 419
 420                                 if (nbytes < 0) {
 421                                         nbytes = 0;
 422                                         read_eof = true;
 423                                 }
 424
 425                                 totalRead += nbytes;
 426                                 result.SetCompleted (false, nbytes + result.NBytes);
 427                                 result.DoCallback ();
 428                                 if (nbytes == 0)
 429                                         contentLength = totalRead;
 430                         }
 431
 432                         lock (locker) {
 433                                 pendingReads--;
 434                                 if (pendingReads == 0)
 435                                         pending.Set ();
 436                         }
 437
 438                         if (totalRead >= contentLength && !nextReadCalled)
 439                                 ReadAll ();
 440
 441                         int nb = result.NBytes;
 442                         return (nb >= 0) ? nb : 0;
 443                 }
 444
 445                 void WriteRequestAsyncCB (IAsyncResult r)
 446                 {
 447                         WebAsyncResult result = (WebAsyncResult) r.AsyncState;
 448                         try {
 449                                 cnc.EndWrite2 (request, r);
 450                                 result.SetCompleted (false, 0);
 451                                 if (!initRead) {
 452                                         initRead = true;
 453                                         WebConnection.InitRead (cnc);
 454                                 }
 455                         } catch (Exception e) {
 456                                 KillBuffer ();
 457                                 nextReadCalled = true;
 458                                 cnc.Close (true);
 459                                 if (e is System.Net.Sockets.SocketException)
 460                                         e = new IOException ("Error writing request", e);
 461                                 result.SetCompleted (false, e);
 462                         }
 463                         complete_request_written = true;
 464                         result.DoCallback ();
 465                 }
 466
 467                 public override IAsyncResult BeginWrite (byte [] buffer, int offset, int size,
 468                                                         AsyncCallback cb, object state)
 469                 {
 470                         if (request.Aborted)
 471                                 throw new WebException ("The request was canceled.", null, WebExceptionStatus.RequestCanceled);
 472
 473                         if (isRead)
 474                                 throw new NotSupportedException ("this stream does not allow writing");
 475
 476                         if (buffer == null)
 477                                 throw new ArgumentNullException ("buffer");
 478
 479                         int length = buffer.Length;
 480                         if (offset < 0 || length < offset)
 481                                 throw new ArgumentOutOfRangeException ("offset");
 482                         if (size < 0 || (length - offset) < size)
 483                                 throw new ArgumentOutOfRangeException ("size");
 484
 485                         if (sendChunked) {
 486                                 lock (locker) {
 487                                         pendingWrites++;
 488                                         pending.Reset ();
 489                                 }
 490                         }
 491
 492                         WebAsyncResult result = new WebAsyncResult (cb, state);
 493                         if (!sendChunked)
 494                                 CheckWriteOverflow (request.ContentLength, totalWritten, size);
 495                         if (allowBuffering && !sendChunked) {
 496                                 if (writeBuffer == null)
 497                                         writeBuffer = new MemoryStream ();
 498                                 writeBuffer.Write (buffer, offset, size);
 499                                 totalWritten += size;
 500                                 if (request.ContentLength > 0 && totalWritten == request.ContentLength) {
 501                                         try {
 502                                                 result.AsyncWriteAll = true;
 503                                                 result.InnerAsyncResult = WriteRequestAsync (new AsyncCallback (WriteRequestAsyncCB), result);
 504                                                 if (result.InnerAsyncResult == null) {
 505                                                         if (!result.IsCompleted)
 506                                                                 result.SetCompleted (true, 0);
 507                                                         result.DoCallback ();
 508                                                 }
 509                                         } catch (Exception exc) {
 510                                                 result.SetCompleted (true, exc);
 511                                                 result.DoCallback ();
 512                                         }
 513                                 } else {
 514                                         result.SetCompleted (true, 0);
 515                                         result.DoCallback ();
 516                                 }
 517                                 return result;
 518                         }
 519
 520                         AsyncCallback callback = null;
 521                         if (cb != null)
 522                                 callback = cb_wrapper;
 523
 524                         if (sendChunked) {
 525                                 WriteRequest ();
 526
 527                                 string cSize = String.Format ("{0:X}\r\n", size);
 528                                 byte [] head = Encoding.ASCII.GetBytes (cSize);
 529                                 int chunkSize = 2 + size + head.Length;
 530                                 byte [] newBuffer = new byte [chunkSize];
 531                                 Buffer.BlockCopy (head, 0, newBuffer, 0, head.Length);
 532                                 Buffer.BlockCopy (buffer, offset, newBuffer, head.Length, size);
 533                                 Buffer.BlockCopy (crlf, 0, newBuffer, head.Length + size, crlf.Length);
 534
 535                                 buffer = newBuffer;
 536                                 offset = 0;
 537                                 size = chunkSize;
 538                         }
 539
 540                         try {
 541                                 result.InnerAsyncResult = cnc.BeginWrite (request, buffer, offset, size, callback, result);
 542                         } catch (Exception) {
 543                                 if (!IgnoreIOErrors)
 544                                         throw;
 545                                 result.SetCompleted (true, 0);
 546                                 result.DoCallback ();
 547                         }
 548                         totalWritten += size;
 549                         return result;
 550                 }
 551
 552                 void CheckWriteOverflow (long contentLength, long totalWritten, long size)
 553                 {
 554                         if (contentLength == -1)
 555                                 return;
 556
 557                         long avail = contentLength - totalWritten;
 558                         if (size > avail) {
 559                                 KillBuffer ();
 560                                 nextReadCalled = true;
 561                                 cnc.Close (true);
 562                                 throw new ProtocolViolationException (
 563                                         "The number of bytes to be written is greater than " +
 564                                         "the specified ContentLength.");
 565                         }
 566                 }
 567
 568                 public override void EndWrite (IAsyncResult r)
 569                 {
 570                         if (r == null)
 571                                 throw new ArgumentNullException ("r");
 572
 573                         WebAsyncResult result = r as WebAsyncResult;
 574                         if (result == null)
 575                                 throw new ArgumentException ("Invalid IAsyncResult");
 576
 577                         if (result.EndCalled)
 578                                 return;
 579
 580                         result.EndCalled = true;
 581                         if (result.AsyncWriteAll) {
 582                                 result.WaitUntilComplete ();
 583                                 if (result.GotException)
 584                                         throw result.Exception;
 585                                 return;
 586                         }
 587
 588                         if (allowBuffering && !sendChunked)
 589                                 return;
 590
 591                         if (result.GotException)
 592                                 throw result.Exception;
 593
 594                         try {
 595                                 cnc.EndWrite2 (request, result.InnerAsyncResult);
 596                                 result.SetCompleted (false, 0);
 597                                 result.DoCallback ();
 598                         } catch (Exception e) {
 599                                 if (IgnoreIOErrors)
 600                                         result.SetCompleted (false, 0);
 601                                 else
 602                                         result.SetCompleted (false, e);
 603                                 result.DoCallback ();
 604                                 if (!IgnoreIOErrors)
 605                                         throw;
 606                         } finally {
 607                                 if (sendChunked) {
 608                                         lock (locker) {
 609                                                 pendingWrites--;
 610                                                 if (pendingWrites == 0)
 611                                                         pending.Set ();
 612                                         }
 613                                 }
 614                         }
 615                 }
 616
 617                 public override void Write (byte [] buffer, int offset, int size)
 618                 {
 619                         AsyncCallback cb = cb_wrapper;
 620                         WebAsyncResult res = (WebAsyncResult) BeginWrite (buffer, offset, size, cb, null);
 621                         if (!res.IsCompleted && !res.WaitUntilComplete (WriteTimeout, false)) {
 622                                 KillBuffer ();
 623                                 nextReadCalled = true;
 624                                 cnc.Close (true);
 625                                 throw new IOException ("Write timed out.");
 626                         }
 627
 628                         EndWrite (res);
 629                 }
 630
 631                 public override void Flush ()
 632                 {
 633                 }
 634
 635                 internal void SetHeadersAsync (byte[] buffer, WebAsyncResult result)
 636                 {
 637                         if (headersSent)
 638                                 return;
 639
 640                         headers = buffer;
 641                         long cl = request.ContentLength;
 642                         string method = request.Method;
 643                         bool no_writestream = (method == "GET" || method == "CONNECT" || method == "HEAD" ||
 644                                                 method == "TRACE");
 645                         bool webdav = (method == "PROPFIND" || method == "PROPPATCH" || method == "MKCOL" ||
 646                                        method == "COPY" || method == "MOVE" || method == "LOCK" ||
 647                                        method == "UNLOCK");
 648                         if (sendChunked || cl > -1 || no_writestream || webdav) {
 649
 650                                 headersSent = true;
 651
 652                                 try {
 653                                         result.InnerAsyncResult = cnc.BeginWrite (request, headers, 0, headers.Length, new AsyncCallback(SetHeadersCB), result);
 654                                         if (result.InnerAsyncResult == null) {
 655                                                 // when does BeginWrite return null? Is the case when the request is aborted?
 656                                                 if (!result.IsCompleted)
 657                                                         result.SetCompleted (true, 0);
 658                                                 result.DoCallback ();
 659                                         }
 660                                 } catch (Exception exc) {
 661                                         result.SetCompleted (true, exc);
 662                                         result.DoCallback ();
 663                                 }
 664                         }
 665                 }
 666
 667                 void SetHeadersCB (IAsyncResult r)
 668                 {
 669                         WebAsyncResult result = (WebAsyncResult) r.AsyncState;
 670                         result.InnerAsyncResult = null;
 671                         try {
 672                                 cnc.EndWrite2 (request, r);
 673                                 result.SetCompleted (false, 0);
 674                                 if (!initRead) {
 675                                         initRead = true;
 676                                         WebConnection.InitRead (cnc);
 677                                 }
 678                                 long cl = request.ContentLength;
 679                                 if (!sendChunked && cl == 0)
 680                                         requestWritten = true;
 681                         } catch (WebException e) {
 682                                 result.SetCompleted (false, e);
 683                         } catch (Exception e) {
 684                                 result.SetCompleted (false, new WebException ("Error writing headers", e, WebExceptionStatus.SendFailure));
 685                         }
 686                         result.DoCallback ();
 687                 }
 688
 689                 internal bool RequestWritten {
 690                         get { return requestWritten; }
 691                 }
 692
 693                 IAsyncResult WriteRequestAsync (AsyncCallback cb, object state)
 694                 {
 695                         requestWritten = true;
 696                         byte [] bytes = writeBuffer.GetBuffer ();
 697                         int length = (int) writeBuffer.Length;
 698                         // Headers already written to the stream
 699                         return (length > 0) ? cnc.BeginWrite (request, bytes, 0, length, cb, state) : null;
 700                 }
 701
 702                 internal void WriteRequest ()
 703                 {
 704                         if (requestWritten)
 705                                 return;
 706
 707                         requestWritten = true;
 708                         if (sendChunked)
 709                                 return;
 710
 711                         if (!allowBuffering || writeBuffer == null)
 712                                 return;
 713
 714                         byte [] bytes = writeBuffer.GetBuffer ();
 715                         int length = (int) writeBuffer.Length;
 716                         if (request.ContentLength != -1 && request.ContentLength < length) {
 717                                 nextReadCalled = true;
 718                                 cnc.Close (true);
 719                                 throw new WebException ("Specified Content-Length is less than the number of bytes to write", null,
 720                                                         WebExceptionStatus.ServerProtocolViolation, null);
 721                         }
 722
 723                         if (!headersSent) {
 724                                 string method = request.Method;
 725                                 bool no_writestream = (method == "GET" || method == "CONNECT" || method == "HEAD" ||
 726                                                         method == "TRACE");
 727                                 if (!no_writestream)
 728                                         request.InternalContentLength = length;
 729
 730                                 byte[] requestHeaders = request.GetRequestHeaders ();
 731                                 WebAsyncResult ar = new WebAsyncResult (null, null);
 732                                 SetHeadersAsync (requestHeaders, ar);
 733                                 ar.AsyncWaitHandle.WaitOne ();
 734                                 if (ar.Exception != null)
 735                                         throw ar.Exception;
 736                         }
 737
 738                         if (cnc.Data.StatusCode != 0 && cnc.Data.StatusCode != 100)
 739                                 return;
 740
 741                         IAsyncResult result = null;
 742                         if (length > 0)
 743                                 result = cnc.BeginWrite (request, bytes, 0, length, null, null);
 744
 745                         if (!initRead) {
 746                                 initRead = true;
 747                                 WebConnection.InitRead (cnc);
 748                         }
 749
 750                         if (length > 0)
 751                                 complete_request_written = cnc.EndWrite (request, result);
 752                         else
 753                                 complete_request_written = true;
 754                 }
 755
 756                 internal void InternalClose ()
 757                 {
 758                         disposed = true;
 759                 }
 760
 761                 public override void Close ()
 762                 {
 763                         if (sendChunked) {
 764                                 if (disposed)
 765                                         return;
 766                                 disposed = true;
 767                                 pending.WaitOne ();
 768                                 byte [] chunk = Encoding.ASCII.GetBytes ("0\r\n\r\n");
 769                                 string err_msg = null;
 770                                 cnc.Write (request, chunk, 0, chunk.Length, ref err_msg);
 771                                 return;
 772                         }
 773
 774                         if (isRead) {
 775                                 if (!nextReadCalled) {
 776                                         CheckComplete ();
 777                                         // If we have not read all the contents
 778                                         if (!nextReadCalled) {
 779                                                 nextReadCalled = true;
 780                                                 cnc.Close (true);
 781                                         }
 782                                 }
 783                                 return;
 784                         } else if (!allowBuffering) {
 785                                 complete_request_written = true;
 786                                 if (!initRead) {
 787                                         initRead = true;
 788                                         WebConnection.InitRead (cnc);
 789                                 }
 790                                 return;
 791                         }
 792
 793                         if (disposed || requestWritten)
 794                                 return;
 795
 796                         long length = request.ContentLength;
 797
 798                         if (!sendChunked && length != -1 && totalWritten != length) {
 799                                 IOException io = new IOException ("Cannot close the stream until all bytes are written");
 800                                 nextReadCalled = true;
 801                                 cnc.Close (true);
 802                                 throw new WebException ("Request was cancelled.", io, WebExceptionStatus.RequestCanceled);
 803                         }
 804
 805                         // Commented out the next line to fix xamarin bug #1512
 806                         //WriteRequest ();
 807                         disposed = true;
 808                 }
 809
 810                 internal void KillBuffer ()
 811                 {
 812                         writeBuffer = null;
 813                 }
 814
 815                 public override long Seek (long a, SeekOrigin b)
 816                 {
 817                         throw new NotSupportedException ();
 818                 }
 819
 820                 public override void SetLength (long a)
 821                 {
 822                         throw new NotSupportedException ();
 823                 }
 824
 825                 public override bool CanSeek {
 826                         get { return false; }
 827                 }
 828
 829                 public override bool CanRead {
 830                         get { return !disposed && isRead; }
 831                 }
 832
 833                 public override bool CanWrite {
 834                         get { return !disposed && !isRead; }
 835                 }
 836
 837                 public override long Length {
 838                         get {
 839                                 if (!isRead)
 840                                         throw new NotSupportedException ();
 841                                 return stream_length;
 842                         }
 843                 }
 844
 845                 public override long Position {
 846                         get { throw new NotSupportedException (); }
 847                         set { throw new NotSupportedException (); }
 848                 }
 849         }
 850 }
 851