src/inspsocket.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2007 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "socket.h"
  15 #include "configreader.h"
  16 #include "inspstring.h"
  17 #include "socketengine.h"
  18 #include "inspircd.h"
  19
  20 using irc::sockets::OpenTCPSocket;
  21 using irc::sockets::insp_inaddr;
  22 using irc::sockets::insp_sockaddr;
  23
  24 bool InspSocket::Readable()
  25 {
  26         return ((this->state != I_CONNECTING) && (this->WaitingForWriteEvent == false));
  27 }
  28
  29 InspSocket::InspSocket(InspIRCd* SI)
  30 {
  31         this->Timeout = NULL;
  32         this->state = I_DISCONNECTED;
  33         this->fd = -1;
  34         this->WaitingForWriteEvent = false;
  35         this->Instance = SI;
  36         this->IsIOHooked = false;
  37 }
  38
  39 InspSocket::InspSocket(InspIRCd* SI, int newfd, const char* ip)
  40 {
  41         this->Timeout = NULL;
  42         this->fd = newfd;
  43         this->state = I_CONNECTED;
  44         strlcpy(this->IP,ip,MAXBUF);
  45         this->WaitingForWriteEvent = false;
  46         this->Instance = SI;
  47         this->IsIOHooked = false;
  48         if (this->fd > -1)
  49                 this->Instance->SE->AddFd(this);
  50 }
  51
  52 InspSocket::InspSocket(InspIRCd* SI, const std::string &ipaddr, int aport, bool listening, unsigned long maxtime, const std::string &connectbindip)
  53 {
  54         this->cbindip = connectbindip;
  55         this->fd = -1;
  56         this->Instance = SI;
  57         strlcpy(host,ipaddr.c_str(),MAXBUF);
  58         this->WaitingForWriteEvent = false;
  59         this->IsIOHooked = false;
  60         this->Timeout = NULL;
  61         if (listening)
  62         {
  63                 if ((this->fd = OpenTCPSocket(host)) == ERROR)
  64                 {
  65                         this->fd = -1;
  66                         this->state = I_ERROR;
  67                         this->OnError(I_ERR_SOCKET);
  68                         return;
  69                 }
  70                 else
  71                 {
  72                         if (!SI->BindSocket(this->fd,aport,(char*)ipaddr.c_str()))
  73                         {
  74                                 this->Close();
  75                                 this->fd = -1;
  76                                 this->state = I_ERROR;
  77                                 this->OnError(I_ERR_BIND);
  78                                 this->ClosePending = true;
  79                                 return;
  80                         }
  81                         else
  82                         {
  83                                 this->state = I_LISTENING;
  84                                 if (this->fd > -1)
  85                                 {
  86                                         if (!this->Instance->SE->AddFd(this))
  87                                         {
  88                                                 this->Close();
  89                                                 this->state = I_ERROR;
  90                                                 this->OnError(I_ERR_NOMOREFDS);
  91                                         }
  92                                 }
  93                                 return;
  94                         }
  95                 }
  96         }
  97         else
  98         {
  99                 strlcpy(this->host,ipaddr.c_str(),MAXBUF);
 100                 this->port = aport;
 101
 102                 bool ipvalid = true;
 103 #ifdef IPV6
 104                 if (strchr(host,':'))
 105                 {
 106                         in6_addr n;
 107                         if (inet_pton(AF_INET6, host, &n) < 1)
 108                                 ipvalid = false;
 109                 }
 110                 else
 111                 {
 112                         in_addr n;
 113                         if (inet_aton(host,&n) < 1)
 114                                 ipvalid = false;
 115                 }
 116 #else
 117                 in_addr n;
 118                 if (inet_aton(host,&n) < 1)
 119                         ipvalid = false;
 120 #endif
 121                 if (!ipvalid)
 122                 {
 123                         this->Instance->Log(DEBUG,"BUG: Hostname passed to InspSocket, rather than an IP address!");
 124                         this->Close();
 125                         this->fd = -1;
 126                         this->state = I_ERROR;
 127                         this->OnError(I_ERR_RESOLVE);
 128                         return;
 129                 }
 130                 else
 131                 {
 132                         strlcpy(this->IP,host,MAXBUF);
 133                         timeout_val = maxtime;
 134                         this->DoConnect();
 135                 }
 136         }
 137 }
 138
 139 void InspSocket::WantWrite()
 140 {
 141         this->Instance->SE->WantWrite(this);
 142         this->WaitingForWriteEvent = true;
 143 }
 144
 145 void InspSocket::SetQueues(int nfd)
 146 {
 147         // attempt to increase socket sendq and recvq as high as its possible
 148         int sendbuf = 32768;
 149         int recvbuf = 32768;
 150         setsockopt(nfd,SOL_SOCKET,SO_SNDBUF,(const void *)&sendbuf,sizeof(sendbuf));
 151         setsockopt(nfd,SOL_SOCKET,SO_RCVBUF,(const void *)&recvbuf,sizeof(sendbuf));
 152 }
 153
 154 /* Most irc servers require you to specify the ip you want to bind to.
 155  * If you dont specify an IP, they rather dumbly bind to the first IP
 156  * of the box (e.g. INADDR_ANY). In InspIRCd, we scan thought the IP
 157  * addresses we've bound server ports to, and we try and bind our outbound
 158  * connections to the first usable non-loopback and non-any IP we find.
 159  * This is easier to configure when you have a lot of links and a lot
 160  * of servers to configure.
 161  */
 162 bool InspSocket::BindAddr(const std::string &ip)
 163 {
 164         ConfigReader Conf(this->Instance);
 165         bool bindfail = false;
 166         socklen_t size = sizeof(sockaddr_in);
 167 #ifdef IPV6
 168         bool v6 = false;
 169         /* Are we looking for a binding to fit an ipv6 host? */
 170         if ((!*this->host) || strchr(this->host, ':'))
 171                 v6 = true;
 172 #endif
 173         int j = 0;
 174         while ((j < Conf.Enumerate("bind")) && (!ip.empty()))
 175         {
 176                 std::string IP = ip.empty() ? Conf.ReadValue("bind","address",j) : ip;
 177                 if (!ip.empty() || Conf.ReadValue("bind","type",j) == "servers")
 178                 {
 179                         if (!ip.empty() || ((IP != "*") && (IP != "127.0.0.1") && (IP != "") && (IP != "::1")))
 180                         {
 181                                 sockaddr* s = new sockaddr[2];
 182 #ifdef IPV6
 183                                 if (v6)
 184                                 {
 185                                         in6_addr n;
 186                                         if (inet_pton(AF_INET6, IP.c_str(), &n) > 0)
 187                                         {
 188                                                 memcpy(&((sockaddr_in6*)s)->sin6_addr, &n, sizeof(n));
 189                                                 ((sockaddr_in6*)s)->sin6_family = AF_INET6;
 190                                                 size = sizeof(sockaddr_in6);
 191                                         }
 192                                         else
 193                                                 bindfail = true;
 194                                 }
 195                                 else
 196                                 {
 197                                         in_addr n;
 198                                         if (inet_aton(IP.c_str(), &n) > 0)
 199                                         {
 200                                                 ((sockaddr_in*)s)->sin_addr = n;
 201                                                 ((sockaddr_in*)s)->sin_family = AF_INET;
 202                                         }
 203                                         else
 204                                                 bindfail = true;
 205                                 }
 206 #else
 207                                 in_addr n;
 208                                 if (insp_aton(IP.c_str(), &n) > 0)
 209                                 {
 210                                         ((sockaddr_in*)s)->sin_addr = n;
 211                                         ((sockaddr_in*)s)->sin_family = AF_INET;
 212                                 }
 213                                 else
 214                                         bindfail = true;
 215 #endif
 216                                 if (bindfail)
 217                                 {
 218                                         delete[] s;
 219                                         return false;
 220                                 }
 221
 222                                 if (bind(this->fd, s, size) < 0)
 223                                 {
 224                                         this->state = I_ERROR;
 225                                         this->OnError(I_ERR_BIND);
 226                                         this->fd = -1;
 227                                         delete[] s;
 228                                         return false;
 229                                 }
 230
 231                                 delete[] s;
 232                                 return true;
 233                         }
 234                 }
 235                 j++;
 236         }
 237         return true;
 238 }
 239
 240 bool InspSocket::DoConnect()
 241 {
 242         sockaddr* addr = new sockaddr[2];
 243         socklen_t size = sizeof(sockaddr_in);
 244 #ifdef IPV6
 245         bool v6 = false;
 246         if ((!*this->host) || strchr(this->host, ':'))
 247                 v6 = true;
 248
 249         if (v6)
 250         {
 251                 this->fd = socket(AF_INET6, SOCK_STREAM, 0);
 252                 if ((this->fd > -1) && ((strstr(this->IP,"::ffff:") != (char*)&this->IP) && (strstr(this->IP,"::FFFF:") != (char*)&this->IP)))
 253                 {
 254                         if (!this->BindAddr(this->cbindip))
 255                         {
 256                                 delete[] addr;
 257                                 return false;
 258                         }
 259                 }
 260         }
 261         else
 262         {
 263                 this->fd = socket(AF_INET, SOCK_STREAM, 0);
 264         }
 265 #else
 266         this->fd = socket(AF_INET, SOCK_STREAM, 0);
 267 #endif
 268
 269         if (this->fd == -1)
 270         {
 271                 this->state = I_ERROR;
 272                 this->OnError(I_ERR_SOCKET);
 273                 delete[] addr;
 274                 return false;
 275         }
 276
 277 #ifdef IPV6
 278         if (v6)
 279         {
 280                 in6_addr addy;
 281                 if (inet_pton(AF_INET6, this->host, &addy) > 0)
 282                 {
 283                         ((sockaddr_in6*)addr)->sin6_family = AF_INET6;
 284                         memcpy(&((sockaddr_in6*)addr)->sin6_addr, &addy, sizeof(addy));
 285                         ((sockaddr_in6*)addr)->sin6_port = htons(this->port);
 286                         size = sizeof(sockaddr_in6);
 287                 }
 288         }
 289         else
 290         {
 291                 in_addr addy;
 292                 if (inet_aton(this->host, &addy) > 0)
 293                 {
 294                         ((sockaddr_in*)addr)->sin_family = AF_INET;
 295                         ((sockaddr_in*)addr)->sin_addr = addy;
 296                         ((sockaddr_in*)addr)->sin_port = htons(this->port);
 297                 }
 298         }
 299 #else
 300         in_addr addy;
 301         if (inet_aton(this->host, &addy) > 0)
 302         {
 303                 ((sockaddr_in*)addr)->sin_family = AF_INET;
 304                 ((sockaddr_in*)addr)->sin_addr = addy;
 305                 ((sockaddr_in*)addr)->sin_port = htons(this->port);
 306         }
 307 #endif
 308
 309         int flags = fcntl(this->fd, F_GETFL, 0);
 310         fcntl(this->fd, F_SETFL, flags | O_NONBLOCK);
 311
 312         if (connect(this->fd, (sockaddr*)addr, size) == -1)
 313         {
 314                 if (errno != EINPROGRESS)
 315                 {
 316                         this->OnError(I_ERR_CONNECT);
 317                         this->Close();
 318                         this->state = I_ERROR;
 319                         return false;
 320                 }
 321
 322                 this->Timeout = new SocketTimeout(this->GetFd(), this->Instance, this, timeout_val, this->Instance->Time());
 323                 this->Instance->Timers->AddTimer(this->Timeout);
 324         }
 325         this->state = I_CONNECTING;
 326         if (this->fd > -1)
 327         {
 328                 if (!this->Instance->SE->AddFd(this))
 329                 {
 330                         this->OnError(I_ERR_NOMOREFDS);
 331                         this->Close();
 332                         this->state = I_ERROR;
 333                         return false;
 334                 }
 335                 this->SetQueues(this->fd);
 336         }
 337         return true;
 338 }
 339
 340
 341 void InspSocket::Close()
 342 {
 343         /* Save this, so we dont lose it,
 344          * otherise on failure, error messages
 345          * might be inaccurate.
 346          */
 347         int save = errno;
 348         if (this->fd > -1)
 349         {
 350                 if (this->IsIOHooked && Instance->Config->GetIOHook(this))
 351                 {
 352                         try
 353                         {
 354                                 Instance->Config->GetIOHook(this)->OnRawSocketClose(this->fd);
 355                         }
 356                         catch (CoreException& modexcept)
 357                         {
 358                                 Instance->Log(DEFAULT,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
 359                         }
 360                 }
 361                 this->OnClose();
 362                 shutdown(this->fd,2);
 363                 close(this->fd);
 364         }
 365         errno = save;
 366 }
 367
 368 std::string InspSocket::GetIP()
 369 {
 370         return this->IP;
 371 }
 372
 373 char* InspSocket::Read()
 374 {
 375         if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 376                 return NULL;
 377
 378         int n = 0;
 379
 380         if (this->IsIOHooked)
 381         {
 382                 int result2 = 0;
 383                 int MOD_RESULT = 0;
 384                 try
 385                 {
 386                         MOD_RESULT = Instance->Config->GetIOHook(this)->OnRawSocketRead(this->fd,this->ibuf,sizeof(this->ibuf),result2);
 387                 }
 388                 catch (CoreException& modexcept)
 389                 {
 390                         Instance->Log(DEFAULT,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
 391                 }
 392                 if (MOD_RESULT < 0)
 393                 {
 394                         n = -1;
 395                         errno = EAGAIN;
 396                 }
 397                 else
 398                 {
 399                         n = result2;
 400                 }
 401         }
 402         else
 403         {
 404                 n = recv(this->fd,this->ibuf,sizeof(this->ibuf),0);
 405         }
 406
 407         if ((n > 0) && (n <= (int)sizeof(this->ibuf)))
 408         {
 409                 ibuf[n] = 0;
 410                 return ibuf;
 411         }
 412         else
 413         {
 414                 int err = errno;
 415                 if (err == EAGAIN)
 416                         return "";
 417                 else
 418                         return NULL;
 419         }
 420 }
 421
 422 void InspSocket::MarkAsClosed()
 423 {
 424 }
 425
 426 // There are two possible outcomes to this function.
 427 // It will either write all of the data, or an undefined amount.
 428 // If an undefined amount is written the connection has failed
 429 // and should be aborted.
 430 int InspSocket::Write(const std::string &data)
 431 {
 432         /* Try and append the data to the back of the queue, and send it on its way
 433          */
 434         outbuffer.push_back(data);
 435         this->Instance->SE->WantWrite(this);
 436         return (!this->FlushWriteBuffer());
 437 }
 438
 439 bool InspSocket::FlushWriteBuffer()
 440 {
 441         errno = 0;
 442         if ((this->fd > -1) && (this->state == I_CONNECTED))
 443         {
 444                 if (this->IsIOHooked)
 445                 {
 446                         while (outbuffer.size() && (errno != EAGAIN))
 447                         {
 448                                 try
 449                                 {
 450                                         int result = Instance->Config->GetIOHook(this)->OnRawSocketWrite(this->fd, outbuffer[0].c_str(), outbuffer[0].length());
 451                                         if (result > 0)
 452                                         {
 453                                                 if ((unsigned int)result == outbuffer[0].length())
 454                                                 {
 455                                                         outbuffer.pop_front();
 456                                                 }
 457                                                 else
 458                                                 {
 459                                                         std::string temp = outbuffer[0].substr(result);
 460                                                         outbuffer[0] = temp;
 461                                                         errno = EAGAIN;
 462                                                 }
 463                                         }
 464                                         else if (((result == -1) && (errno != EAGAIN)) || (result == 0))
 465                                         {
 466                                                 this->OnError(I_ERR_WRITE);
 467                                                 this->state = I_ERROR;
 468                                                 this->Instance->SE->DelFd(this);
 469                                                 this->Close();
 470                                                 return true;
 471                                         }
 472                                 }
 473                                 catch (CoreException& modexcept)
 474                                 {
 475                                         Instance->Log(DEBUG,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
 476                                         return true;
 477                                 }
 478                         }
 479                 }
 480                 else
 481                 {
 482                         /* If we have multiple lines, try to send them all,
 483                          * not just the first one -- Brain
 484                          */
 485                         while (outbuffer.size() && (errno != EAGAIN))
 486                         {
 487                                 /* Send a line */
 488                                 int result = write(this->fd,outbuffer[0].c_str(),outbuffer[0].length());
 489                                 if (result > 0)
 490                                 {
 491                                         if ((unsigned int)result == outbuffer[0].length())
 492                                         {
 493                                                 /* The whole block was written (usually a line)
 494                                                  * Pop the block off the front of the queue,
 495                                                  * dont set errno, because we are clear of errors
 496                                                  * and want to try and write the next block too.
 497                                                  */
 498                                                 outbuffer.pop_front();
 499                                         }
 500                                         else
 501                                         {
 502                                                 std::string temp = outbuffer[0].substr(result);
 503                                                 outbuffer[0] = temp;
 504                                                 /* We didnt get the whole line out. arses.
 505                                                  * Try again next time, i guess. Set errno,
 506                                                  * because we shouldnt be writing any more now,
 507                                                  * until the socketengine says its safe to do so.
 508                                                  */
 509                                                 errno = EAGAIN;
 510                                         }
 511                                 }
 512                                 else if ((result == -1) && (errno != EAGAIN))
 513                                 {
 514                                         this->OnError(I_ERR_WRITE);
 515                                         this->state = I_ERROR;
 516                                         this->Instance->SE->DelFd(this);
 517                                         this->Close();
 518                                         return true;
 519                                 }
 520                         }
 521                 }
 522         }
 523
 524         if ((errno == EAGAIN) && (fd > -1))
 525         {
 526                 this->Instance->SE->WantWrite(this);
 527         }
 528
 529         return (fd < 0);
 530 }
 531
 532 void SocketTimeout::Tick(time_t now)
 533 {
 534         if (ServerInstance->SE->GetRef(this->sfd) != this->sock)
 535                 return;
 536
 537         if (this->sock->state == I_CONNECTING)
 538         {
 539                 // for non-listening sockets, the timeout can occur
 540                 // which causes termination of the connection after
 541                 // the given number of seconds without a successful
 542                 // connection.
 543                 this->sock->OnTimeout();
 544                 this->sock->OnError(I_ERR_TIMEOUT);
 545                 this->sock->timeout = true;
 546                 ServerInstance->SE->DelFd(this->sock);
 547                 /* NOTE: We must set this AFTER DelFd, as we added
 548                  * this socket whilst writeable. This means that we
 549                  * must DELETE the socket whilst writeable too!
 550                  */
 551                 this->sock->state = I_ERROR;
 552                 this->sock->Close();
 553                 delete this->sock;
 554                 return;
 555         }
 556         else
 557         {
 558                 this->sock->Timeout = NULL;
 559         }
 560 }
 561
 562 bool InspSocket::Poll()
 563 {
 564         if (this->Instance->SE->GetRef(this->fd) != this)
 565                 return false;
 566
 567         int incoming = -1;
 568
 569         if ((fd < 0) || (fd > MAX_DESCRIPTORS))
 570                 return false;
 571
 572         switch (this->state)
 573         {
 574                 case I_CONNECTING:
 575                         /* Our socket was in write-state, so delete it and re-add it
 576                          * in read-state.
 577                          */
 578                         if (this->fd > -1)
 579                         {
 580                                 this->Instance->SE->DelFd(this);
 581                                 this->SetState(I_CONNECTED);
 582                                 if (!this->Instance->SE->AddFd(this))
 583                                         return false;
 584                         }
 585                         if (Instance->Config->GetIOHook(this))
 586                         {
 587                                 try
 588                                 {
 589                                         Instance->Config->GetIOHook(this)->OnRawSocketConnect(this->fd);
 590                                 }
 591                                 catch (CoreException& modexcept)
 592                                 {
 593                                         Instance->Log(DEBUG,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
 594                                 }
 595                         }
 596                         return this->OnConnected();
 597                 break;
 598                 case I_LISTENING:
 599                 {
 600                         sockaddr* client = new sockaddr[2];
 601                         length = sizeof (sockaddr_in);
 602                         std::string recvip;
 603 #ifdef IPV6
 604                         if ((!*this->host) || strchr(this->host, ':'))
 605                                 length = sizeof(sockaddr_in6);
 606 #endif
 607                         incoming = accept (this->fd, client, &length);
 608 #ifdef IPV6
 609                         if ((!*this->host) || strchr(this->host, ':'))
 610                         {
 611                                 char buf[1024];
 612                                 recvip = inet_ntop(AF_INET6, &((sockaddr_in6*)client)->sin6_addr, buf, sizeof(buf));
 613                         }
 614                         else
 615                         {
 616                                 recvip = inet_ntoa(((sockaddr_in*)client)->sin_addr);
 617                         }
 618 #else
 619                         recvip = inet_ntoa(((sockaddr_in*)client)->sin_addr);
 620 #endif
 621                         this->OnIncomingConnection(incoming, (char*)recvip.c_str());
 622
 623                         if (this->IsIOHooked)
 624                         {
 625                                 try
 626                                 {
 627                                         Instance->Config->GetIOHook(this)->OnRawSocketAccept(incoming, recvip.c_str(), this->port);
 628                                 }
 629                                 catch (CoreException& modexcept)
 630                                 {
 631                                         Instance->Log(DEBUG,"%s threw an exception: %s", modexcept.GetSource(), modexcept.GetReason());
 632                                 }
 633                         }
 634
 635                         this->SetQueues(incoming);
 636
 637                         delete[] client;
 638                         return true;
 639                 }
 640                 break;
 641                 case I_CONNECTED:
 642                         /* Process the read event */
 643                         return this->OnDataReady();
 644                 break;
 645                 default:
 646                 break;
 647         }
 648         return true;
 649 }
 650
 651 void InspSocket::SetState(InspSocketState s)
 652 {
 653         this->state = s;
 654 }
 655
 656 InspSocketState InspSocket::GetState()
 657 {
 658         return this->state;
 659 }
 660
 661 int InspSocket::GetFd()
 662 {
 663         return this->fd;
 664 }
 665
 666 bool InspSocket::OnConnected() { return true; }
 667 void InspSocket::OnError(InspSocketError e) { return; }
 668 int InspSocket::OnDisconnect() { return 0; }
 669 int InspSocket::OnIncomingConnection(int newfd, char* ip) { return 0; }
 670 bool InspSocket::OnDataReady() { return true; }
 671 bool InspSocket::OnWriteReady() { return true; }
 672 void InspSocket::OnTimeout() { return; }
 673 void InspSocket::OnClose() { return; }
 674
 675 InspSocket::~InspSocket()
 676 {
 677         this->Close();
 678         if (Timeout)
 679         {
 680                 Instance->Timers->DelTimer(Timeout);
 681                 Timeout = NULL;
 682         }
 683 }
 684
 685 void InspSocket::HandleEvent(EventType et, int errornum)
 686 {
 687         switch (et)
 688         {
 689                 case EVENT_ERROR:
 690                         this->Instance->SE->DelFd(this);
 691                         this->Close();
 692                         delete this;
 693                         return;
 694                 break;
 695                 case EVENT_READ:
 696                         if (!this->Poll())
 697                         {
 698                                 this->Instance->SE->DelFd(this);
 699                                 this->Close();
 700                                 delete this;
 701                                 return;
 702                         }
 703                 break;
 704                 case EVENT_WRITE:
 705                         if (this->WaitingForWriteEvent)
 706                         {
 707                                 this->WaitingForWriteEvent = false;
 708                                 if (!this->OnWriteReady())
 709                                 {
 710                                         this->Instance->SE->DelFd(this);
 711                                         this->Close();
 712                                         delete this;
 713                                         return;
 714                                 }
 715                         }
 716                         if (this->state == I_CONNECTING)
 717                         {
 718                                 /* This might look wrong as if we should be actually calling
 719                                  * with EVENT_WRITE, but trust me it is correct. There are some
 720                                  * writeability-state things in the read code, because of how
 721                                  * InspSocket used to work regarding write buffering in previous
 722                                  * versions of InspIRCd. - Brain
 723                                  */
 724                                 this->HandleEvent(EVENT_READ);
 725                                 return;
 726                         }
 727                         else
 728                         {
 729                                 if (this->FlushWriteBuffer())
 730                                 {
 731                                         this->Instance->SE->DelFd(this);
 732                                         this->Close();
 733                                         delete this;
 734                                         return;
 735                                 }
 736                         }
 737                 break;
 738         }
 739 }
 740