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                 long contentLength;
  49                 long 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 = Int64.MaxValue;
  97                                 }
  98                         } else {
  99                                 contentLength = Int64.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 CheckAuthHeader (string headerName)
 124                 {
 125                         var authHeader = cnc.Data.Headers [headerName];
 126                         return (authHeader != null && authHeader.IndexOf ("NTLM", StringComparison.Ordinal) != -1);
 127                 }
 128
 129                 bool IsNtlmAuth ()
 130                 {
 131                         bool isProxy = (request.Proxy != null && !request.Proxy.IsBypassed (request.Address));
 132                         if (isProxy && CheckAuthHeader ("Proxy-Authenticate"))
 133                                 return true;
 134                         return CheckAuthHeader ("WWW-Authenticate");
 135                 }
 136
 137                 internal void CheckResponseInBuffer ()
 138                 {
 139                         if (contentLength > 0 && (readBufferSize - readBufferOffset) >= contentLength) {
 140                                 if (!IsNtlmAuth ())
 141                                         ReadAll ();
 142                         }
 143                 }
 144
 145                 internal HttpWebRequest Request {
 146                         get { return request; }
 147                 }
 148
 149                 internal WebConnection Connection {
 150                         get { return cnc; }
 151                 }
 152                 public override bool CanTimeout {
 153                         get { return true; }
 154                 }
 155
 156                 public override int ReadTimeout {
 157                         get {
 158                                 return read_timeout;
 159                         }
 160
 161                         set {
 162                                 if (value < -1)
 163                                         throw new ArgumentOutOfRangeException ("value");
 164                                 read_timeout = value;
 165                         }
 166                 }
 167
 168                 public override int WriteTimeout {
 169                         get {
 170                                 return write_timeout;
 171                         }
 172
 173                         set {
 174                                 if (value < -1)
 175                                         throw new ArgumentOutOfRangeException ("value");
 176                                 write_timeout = value;
 177                         }
 178                 }
 179
 180                 internal bool CompleteRequestWritten {
 181                         get { return complete_request_written; }
 182                 }
 183
 184                 internal bool SendChunked {
 185                         set { sendChunked = value; }
 186                 }
 187
 188                 internal byte [] ReadBuffer {
 189                         set { readBuffer = value; }
 190                 }
 191
 192                 internal int ReadBufferOffset {
 193                         set { readBufferOffset = value; }
 194                 }
 195
 196                 internal int ReadBufferSize {
 197                         set { readBufferSize = value; }
 198                 }
 199
 200                 internal byte[] WriteBuffer {
 201                         get { return writeBuffer.GetBuffer (); }
 202                 }
 203
 204                 internal int WriteBufferLength {
 205                         get { return writeBuffer != null ? (int) writeBuffer.Length : (-1); }
 206                 }
 207
 208                 internal void ForceCompletion ()
 209                 {
 210                         if (!nextReadCalled) {
 211                                 if (contentLength == Int64.MaxValue)
 212                                         contentLength = 0;
 213                                 nextReadCalled = true;
 214                                 cnc.NextRead ();
 215                         }
 216                 }
 217
 218                 internal void CheckComplete ()
 219                 {
 220                         bool nrc = nextReadCalled;
 221                         if (!nrc && readBufferSize - readBufferOffset == contentLength) {
 222                                 nextReadCalled = true;
 223                                 cnc.NextRead ();
 224                         }
 225                 }
 226
 227                 internal void ReadAll ()
 228                 {
 229                         if (!isRead || read_eof || totalRead >= contentLength || nextReadCalled) {
 230                                 if (isRead && !nextReadCalled) {
 231                                         nextReadCalled = true;
 232                                         cnc.NextRead ();
 233                                 }
 234                                 return;
 235                         }
 236
 237                         if (!pending.WaitOne (ReadTimeout))
 238                                 throw new WebException ("The operation has timed out.", WebExceptionStatus.Timeout);
 239                         lock (locker) {
 240                                 if (totalRead >= contentLength)
 241                                         return;
 242
 243                                 byte [] b = null;
 244                                 int diff = readBufferSize - readBufferOffset;
 245                                 int new_size;
 246
 247                                 if (contentLength == Int64.MaxValue) {
 248                                         MemoryStream ms = new MemoryStream ();
 249                                         byte [] buffer = null;
 250                                         if (readBuffer != null && diff > 0) {
 251                                                 ms.Write (readBuffer, readBufferOffset, diff);
 252                                                 if (readBufferSize >= 8192)
 253                                                         buffer = readBuffer;
 254                                         }
 255
 256                                         if (buffer == null)
 257                                                 buffer = new byte [8192];
 258
 259                                         int read;
 260                                         while ((read = cnc.Read (request, buffer, 0, buffer.Length)) != 0)
 261                                                 ms.Write (buffer, 0, read);
 262
 263                                         b = ms.GetBuffer ();
 264                                         new_size = (int) ms.Length;
 265                                         contentLength = new_size;
 266                                 } else {
 267                                         new_size = (int) (contentLength - totalRead);
 268                                         b = new byte [new_size];
 269                                         if (readBuffer != null && diff > 0) {
 270                                                 if (diff > new_size)
 271                                                         diff = new_size;
 272
 273                                                 Buffer.BlockCopy (readBuffer, readBufferOffset, b, 0, diff);
 274                                         }
 275
 276                                         int remaining = new_size - diff;
 277                                         int r = -1;
 278                                         while (remaining > 0 && r != 0) {
 279                                                 r = cnc.Read (request, b, diff, remaining);
 280                                                 remaining -= r;
 281                                                 diff += r;
 282                                         }
 283                                 }
 284
 285                                 readBuffer = b;
 286                                 readBufferOffset = 0;
 287                                 readBufferSize = new_size;
 288                                 totalRead = 0;
 289                                 nextReadCalled = true;
 290                         }
 291
 292                         cnc.NextRead ();
 293                 }
 294
 295                 void WriteCallbackWrapper (IAsyncResult r)
 296                 {
 297                         WebAsyncResult result = r as WebAsyncResult;
 298                         if (result != null && result.AsyncWriteAll)
 299                                 return;
 300
 301                         if (r.AsyncState != null) {
 302                                 result = (WebAsyncResult) r.AsyncState;
 303                                 result.InnerAsyncResult = r;
 304                                 result.DoCallback ();
 305                         } else {
 306                                 try {
 307                                         EndWrite (r);
 308                                 } catch {
 309                                 }
 310                         }
 311                 }
 312
 313                 void ReadCallbackWrapper (IAsyncResult r)
 314                 {
 315                         WebAsyncResult result;
 316                         if (r.AsyncState != null) {
 317                                 result = (WebAsyncResult) r.AsyncState;
 318                                 result.InnerAsyncResult = r;
 319                                 result.DoCallback ();
 320                         } else {
 321                                 try {
 322                                         EndRead (r);
 323                                 } catch {
 324                                 }
 325                         }
 326                 }
 327
 328                 public override int Read (byte [] buffer, int offset, int size)
 329                 {
 330                         AsyncCallback cb = cb_wrapper;
 331                         WebAsyncResult res = (WebAsyncResult) BeginRead (buffer, offset, size, cb, null);
 332                         if (!res.IsCompleted && !res.WaitUntilComplete (ReadTimeout, false)) {
 333                                 nextReadCalled = true;
 334                                 cnc.Close (true);
 335                                 throw new WebException ("The operation has timed out.", WebExceptionStatus.Timeout);
 336                         }
 337
 338                         return EndRead (res);
 339                 }
 340
 341                 public override IAsyncResult BeginRead (byte [] buffer, int offset, int size,
 342                                                         AsyncCallback cb, object state)
 343                 {
 344                         if (!isRead)
 345                                 throw new NotSupportedException ("this stream does not allow reading");
 346
 347                         if (buffer == null)
 348                                 throw new ArgumentNullException ("buffer");
 349
 350                         int length = buffer.Length;
 351                         if (offset < 0 || length < offset)
 352                                 throw new ArgumentOutOfRangeException ("offset");
 353                         if (size < 0 || (length - offset) < size)
 354                                 throw new ArgumentOutOfRangeException ("size");
 355
 356                         lock (locker) {
 357                                 pendingReads++;
 358                                 pending.Reset ();
 359                         }
 360
 361                         WebAsyncResult result = new WebAsyncResult (cb, state, buffer, offset, size);
 362                         result.AsyncObject = request;
 363                         if (totalRead >= contentLength) {
 364                                 result.SetCompleted (true, -1);
 365                                 result.DoCallback ();
 366                                 return result;
 367                         }
 368
 369                         int remaining = readBufferSize - readBufferOffset;
 370                         if (remaining > 0) {
 371                                 int copy = (remaining > size) ? size : remaining;
 372                                 Buffer.BlockCopy (readBuffer, readBufferOffset, buffer, offset, copy);
 373                                 readBufferOffset += copy;
 374                                 offset += copy;
 375                                 size -= copy;
 376                                 totalRead += copy;
 377                                 if (size == 0 || totalRead >= contentLength) {
 378                                         result.SetCompleted (true, copy);
 379                                         result.DoCallback ();
 380                                         return result;
 381                                 }
 382                                 result.NBytes = copy;
 383                         }
 384
 385                         if (cb != null)
 386                                 cb = cb_wrapper;
 387
 388                         if (contentLength != Int64.MaxValue && contentLength - totalRead < size)
 389                                 size = (int)(contentLength - totalRead);
 390
 391                         if (!read_eof) {
 392                                 cnc.ReadAsync (request, buffer, offset, size, result);
 393                         } else {
 394                                 result.SetCompleted (true, result.NBytes);
 395                                 result.DoCallback ();
 396                         }
 397                         return result;
 398                 }
 399
 400                 public override int EndRead (IAsyncResult r)
 401                 {
 402                         WebAsyncResult result = (WebAsyncResult) r;
 403                         int nb = result.NBytes;
 404
 405                         if (result.EndCalled)
 406                                 return (nb >= 0) ? nb : 0;
 407                         result.EndCalled = true;
 408
 409                         lock (locker) {
 410                                 pendingReads--;
 411                                 if (pendingReads == 0)
 412                                         pending.Set ();
 413                         }
 414
 415                         if (result.GotException) {
 416                                 nextReadCalled = true;
 417                                 cnc.Close (true);
 418                                 throw result.Exception;
 419                         }
 420
 421                         if (nb < 0) {
 422                                 read_eof = true;
 423                         } else {
 424                                 totalRead += result.NBytes;
 425                                 if (nb == 0)
 426                                         contentLength = totalRead;
 427                         }
 428
 429                         if (totalRead >= contentLength && !nextReadCalled)
 430                                 ReadAll ();
 431
 432                         return (nb >= 0) ? nb : 0;
 433                 }
 434
 435                 void WriteAsyncCB (IAsyncResult r)
 436                 {
 437                         WebAsyncResult result = (WebAsyncResult) r.AsyncState;
 438                         result.InnerAsyncResult = null;
 439
 440                         try {
 441                                 cnc.EndWrite (request, true, r);
 442                                 result.SetCompleted (false, 0);
 443                                 if (!initRead) {
 444                                         initRead = true;
 445                                         WebConnection.InitRead (cnc);
 446                                 }
 447                         } catch (Exception e) {
 448                                 KillBuffer ();
 449                                 nextReadCalled = true;
 450                                 cnc.Close (true);
 451                                 if (e is System.Net.Sockets.SocketException)
 452                                         e = new IOException ("Error writing request", e);
 453                                 result.SetCompleted (false, e);
 454                         }
 455
 456                         if (allowBuffering && !sendChunked && request.ContentLength > 0 && totalWritten == request.ContentLength)
 457                                 complete_request_written = true;
 458
 459                         result.DoCallback ();
 460                 }
 461
 462                 public override IAsyncResult BeginWrite (byte [] buffer, int offset, int size,
 463                                                         AsyncCallback cb, object state)
 464                 {
 465                         if (request.Aborted)
 466                                 throw new WebException ("The request was canceled.", null, WebExceptionStatus.RequestCanceled);
 467
 468                         if (isRead)
 469                                 throw new NotSupportedException ("this stream does not allow writing");
 470
 471                         if (buffer == null)
 472                                 throw new ArgumentNullException ("buffer");
 473
 474                         int length = buffer.Length;
 475                         if (offset < 0 || length < offset)
 476                                 throw new ArgumentOutOfRangeException ("offset");
 477                         if (size < 0 || (length - offset) < size)
 478                                 throw new ArgumentOutOfRangeException ("size");
 479
 480                         if (sendChunked) {
 481                                 lock (locker) {
 482                                         pendingWrites++;
 483                                         pending.Reset ();
 484                                 }
 485                         }
 486
 487                         WebAsyncResult result = new WebAsyncResult (cb, state);
 488                         AsyncCallback callback = new AsyncCallback (WriteAsyncCB);
 489
 490                         if (sendChunked) {
 491                                 requestWritten = true;
 492
 493                                 string cSize = String.Format ("{0:X}\r\n", size);
 494                                 byte[] head = Encoding.ASCII.GetBytes (cSize);
 495                                 int chunkSize = 2 + size + head.Length;
 496                                 byte[] newBuffer = new byte [chunkSize];
 497                                 Buffer.BlockCopy (head, 0, newBuffer, 0, head.Length);
 498                                 Buffer.BlockCopy (buffer, offset, newBuffer, head.Length, size);
 499                                 Buffer.BlockCopy (crlf, 0, newBuffer, head.Length + size, crlf.Length);
 500
 501                                 if (allowBuffering) {
 502                                         if (writeBuffer == null)
 503                                                 writeBuffer = new MemoryStream ();
 504                                         writeBuffer.Write (buffer, offset, size);
 505                                         totalWritten += size;
 506                                 }
 507
 508                                 buffer = newBuffer;
 509                                 offset = 0;
 510                                 size = chunkSize;
 511                         } else {
 512                                 CheckWriteOverflow (request.ContentLength, totalWritten, size);
 513
 514                                 if (allowBuffering) {
 515                                         if (writeBuffer == null)
 516                                                 writeBuffer = new MemoryStream ();
 517                                         writeBuffer.Write (buffer, offset, size);
 518                                         totalWritten += size;
 519
 520                                         if (request.ContentLength <= 0 || totalWritten < request.ContentLength) {
 521                                                 result.SetCompleted (true, 0);
 522                                                 result.DoCallback ();
 523                                                 return result;
 524                                         }
 525
 526                                         result.AsyncWriteAll = true;
 527                                         requestWritten = true;
 528                                         buffer = writeBuffer.GetBuffer ();
 529                                         offset = 0;
 530                                         size = (int)totalWritten;
 531                                 }
 532                         }
 533
 534                         try {
 535                                 result.InnerAsyncResult = cnc.BeginWrite (request, buffer, offset, size, callback, result);
 536                                 if (result.InnerAsyncResult == null) {
 537                                         if (!result.IsCompleted)
 538                                                 result.SetCompleted (true, 0);
 539                                         result.DoCallback ();
 540                                 }
 541                         } catch (Exception) {
 542                                 if (!IgnoreIOErrors)
 543                                         throw;
 544                                 result.SetCompleted (true, 0);
 545                                 result.DoCallback ();
 546                         }
 547                         totalWritten += size;
 548                         return result;
 549                 }
 550
 551                 void CheckWriteOverflow (long contentLength, long totalWritten, long size)
 552                 {
 553                         if (contentLength == -1)
 554                                 return;
 555
 556                         long avail = contentLength - totalWritten;
 557                         if (size > avail) {
 558                                 KillBuffer ();
 559                                 nextReadCalled = true;
 560                                 cnc.Close (true);
 561                                 throw new ProtocolViolationException (
 562                                         "The number of bytes to be written is greater than " +
 563                                         "the specified ContentLength.");
 564                         }
 565                 }
 566
 567                 public override void EndWrite (IAsyncResult r)
 568                 {
 569                         if (r == null)
 570                                 throw new ArgumentNullException ("r");
 571
 572                         WebAsyncResult result = r as WebAsyncResult;
 573                         if (result == null)
 574                                 throw new ArgumentException ("Invalid IAsyncResult");
 575
 576                         if (result.EndCalled)
 577                                 return;
 578
 579                         if (sendChunked) {
 580                                 lock (locker) {
 581                                         pendingWrites--;
 582                                         if (pendingWrites <= 0)
 583                                                 pending.Set ();
 584                                 }
 585                         }
 586
 587                         result.EndCalled = true;
 588                         if (result.AsyncWriteAll) {
 589                                 result.WaitUntilComplete ();
 590                                 if (result.GotException)
 591                                         throw result.Exception;
 592                                 return;
 593                         }
 594
 595                         if (allowBuffering && !sendChunked)
 596                                 return;
 597
 598                         if (result.GotException)
 599                                 throw result.Exception;
 600                 }
 601
 602                 public override void Write (byte [] buffer, int offset, int size)
 603                 {
 604                         AsyncCallback cb = cb_wrapper;
 605                         WebAsyncResult res = (WebAsyncResult) BeginWrite (buffer, offset, size, cb, null);
 606                         if (!res.IsCompleted && !res.WaitUntilComplete (WriteTimeout, false)) {
 607                                 KillBuffer ();
 608                                 nextReadCalled = true;
 609                                 cnc.Close (true);
 610                                 throw new IOException ("Write timed out.");
 611                         }
 612
 613                         EndWrite (res);
 614                 }
 615
 616                 public override void Flush ()
 617                 {
 618                 }
 619
 620                 internal void SetHeadersAsync (bool setInternalLength, SimpleAsyncCallback callback)
 621                 {
 622                         SimpleAsyncResult.Run (r => SetHeadersAsync (r, setInternalLength), callback);
 623                 }
 624
 625                 bool SetHeadersAsync (SimpleAsyncResult result, bool setInternalLength)
 626                 {
 627                         if (headersSent)
 628                                 return false;
 629
 630                         string method = request.Method;
 631                         bool no_writestream = (method == "GET" || method == "CONNECT" || method == "HEAD" ||
 632                                               method == "TRACE");
 633                         bool webdav = (method == "PROPFIND" || method == "PROPPATCH" || method == "MKCOL" ||
 634                                       method == "COPY" || method == "MOVE" || method == "LOCK" ||
 635                                       method == "UNLOCK");
 636
 637                         if (setInternalLength && !no_writestream && writeBuffer != null)
 638                                 request.InternalContentLength = writeBuffer.Length;
 639
 640                         bool has_content = !no_writestream && (writeBuffer == null || request.ContentLength > -1);
 641                         if (!(sendChunked || has_content || no_writestream || webdav))
 642                                 return false;
 643
 644                         headersSent = true;
 645                         headers = request.GetRequestHeaders ();
 646
 647                         var innerResult = cnc.BeginWrite (request, headers, 0, headers.Length, r => {
 648                                 try {
 649                                         cnc.EndWrite (request, true, r);
 650                                         if (!initRead) {
 651                                                 initRead = true;
 652                                                 WebConnection.InitRead (cnc);
 653                                         }
 654                                         var cl = request.ContentLength;
 655                                         if (!sendChunked && cl == 0)
 656                                                 requestWritten = true;
 657                                         result.SetCompleted (false);
 658                                 } catch (WebException e) {
 659                                         result.SetCompleted (false, e);
 660                                 } catch (Exception e) {
 661                                         result.SetCompleted (false, new WebException ("Error writing headers", e, WebExceptionStatus.SendFailure));
 662                                 }
 663                         }, null);
 664
 665                         return innerResult != null;
 666                 }
 667
 668                 internal bool RequestWritten {
 669                         get { return requestWritten; }
 670                 }
 671
 672                 internal SimpleAsyncResult WriteRequestAsync (SimpleAsyncCallback callback)
 673                 {
 674                         var result = WriteRequestAsync (callback);
 675                         try {
 676                                 if (!WriteRequestAsync (result))
 677                                         result.SetCompleted (true);
 678                         } catch (Exception ex) {
 679                                 result.SetCompleted (true, ex);
 680                         }
 681                         return result;
 682                 }
 683
 684                 internal bool WriteRequestAsync (SimpleAsyncResult result)
 685                 {
 686                         if (requestWritten)
 687                                 return false;
 688
 689                         requestWritten = true;
 690                         if (sendChunked || !allowBuffering || writeBuffer == null)
 691                                 return false;
 692
 693                         // Keep the call for a potential side-effect of GetBuffer
 694                         var bytes = writeBuffer.GetBuffer ();
 695                         var length = (int)writeBuffer.Length;
 696                         if (request.ContentLength != -1 && request.ContentLength < length) {
 697                                 nextReadCalled = true;
 698                                 cnc.Close (true);
 699                                 throw new WebException ("Specified Content-Length is less than the number of bytes to write", null,
 700                                         WebExceptionStatus.ServerProtocolViolation, null);
 701                         }
 702
 703                         SetHeadersAsync (true, inner => {
 704                                 if (inner.GotException) {
 705                                         result.SetCompleted (inner.CompletedSynchronously, inner.Exception);
 706                                         return;
 707                                 }
 708
 709                                 if (cnc.Data.StatusCode != 0 && cnc.Data.StatusCode != 100) {
 710                                         result.SetCompleted (inner.CompletedSynchronously);
 711                                         return;
 712                                 }
 713
 714                                 if (!initRead) {
 715                                         initRead = true;
 716                                         WebConnection.InitRead (cnc);
 717                                 }
 718
 719                                 if (length == 0) {
 720                                         complete_request_written = true;
 721                                         result.SetCompleted (inner.CompletedSynchronously);
 722                                         return;
 723                                 }
 724
 725                                 cnc.BeginWrite (request, bytes, 0, length, r => {
 726                                         try {
 727                                                 complete_request_written = cnc.EndWrite (request, false, r);
 728                                                 result.SetCompleted (false);
 729                                         } catch (Exception exc) {
 730                                                 result.SetCompleted (false, exc);
 731                                         }
 732                                 }, null);
 733                         });
 734
 735                         return true;
 736                 }
 737
 738                 internal void InternalClose ()
 739                 {
 740                         disposed = true;
 741                 }
 742
 743                 internal bool GetResponseOnClose {
 744                         get; set;
 745                 }
 746
 747                 public override void Close ()
 748                 {
 749                         if (GetResponseOnClose) {
 750                                 if (disposed)
 751                                         return;
 752                                 disposed = true;
 753                                 var response = (HttpWebResponse)request.GetResponse ();
 754                                 response.ReadAll ();
 755                                 response.Close ();
 756                                 return;
 757                         }
 758
 759                         if (sendChunked) {
 760                                 if (disposed)
 761                                         return;
 762                                 disposed = true;
 763                                 if (!pending.WaitOne (WriteTimeout)) {
 764                                         throw new WebException ("The operation has timed out.", WebExceptionStatus.Timeout);
 765                                 }
 766                                 byte [] chunk = Encoding.ASCII.GetBytes ("0\r\n\r\n");
 767                                 string err_msg = null;
 768                                 cnc.Write (request, chunk, 0, chunk.Length, ref err_msg);
 769                                 return;
 770                         }
 771
 772                         if (isRead) {
 773                                 if (!nextReadCalled) {
 774                                         CheckComplete ();
 775                                         // If we have not read all the contents
 776                                         if (!nextReadCalled) {
 777                                                 nextReadCalled = true;
 778                                                 cnc.Close (true);
 779                                         }
 780                                 }
 781                                 return;
 782                         } else if (!allowBuffering) {
 783                                 complete_request_written = true;
 784                                 if (!initRead) {
 785                                         initRead = true;
 786                                         WebConnection.InitRead (cnc);
 787                                 }
 788                                 return;
 789                         }
 790
 791                         if (disposed || requestWritten)
 792                                 return;
 793
 794                         long length = request.ContentLength;
 795
 796                         if (!sendChunked && length != -1 && totalWritten != length) {
 797                                 IOException io = new IOException ("Cannot close the stream until all bytes are written");
 798                                 nextReadCalled = true;
 799                                 cnc.Close (true);
 800                                 throw new WebException ("Request was cancelled.", io, WebExceptionStatus.RequestCanceled);
 801                         }
 802
 803                         // Commented out the next line to fix xamarin bug #1512
 804                         //WriteRequest ();
 805                         disposed = true;
 806                 }
 807
 808                 internal void KillBuffer ()
 809                 {
 810                         writeBuffer = null;
 811                 }
 812
 813                 public override long Seek (long a, SeekOrigin b)
 814                 {
 815                         throw new NotSupportedException ();
 816                 }
 817
 818                 public override void SetLength (long a)
 819                 {
 820                         throw new NotSupportedException ();
 821                 }
 822
 823                 public override bool CanSeek {
 824                         get { return false; }
 825                 }
 826
 827                 public override bool CanRead {
 828                         get { return !disposed && isRead; }
 829                 }
 830
 831                 public override bool CanWrite {
 832                         get { return !disposed && !isRead; }
 833                 }
 834
 835                 public override long Length {
 836                         get {
 837                                 if (!isRead)
 838                                         throw new NotSupportedException ();
 839                                 return stream_length;
 840                         }
 841                 }
 842
 843                 public override long Position {
 844                         get { throw new NotSupportedException (); }
 845                         set { throw new NotSupportedException (); }
 846                 }
 847         }
 848 }
 849