src/inetfile/chttpget.cpp

   1 /*
   2  * Copyright (C) Volition, Inc. 1999.  All rights reserved.
   3  *
   4  * All source code herein is the property of Volition, Inc. You may not sell
   5  * or otherwise commercially exploit the source or things you created based on
   6  * the source.
   7  */
   8
   9 /*
  10 * $Logfile: /Freespace2/code/Inetfile/Chttpget.cpp $
  11 * $Revision$
  12 * $Date$
  13 * $Author$
  14 *
  15 * HTTP Client class (get only)
  16 *
  17 * $Log$
  18 * Revision 1.8  2002/06/21 03:04:12  relnev
  19 * nothing important
  20 *
  21 * Revision 1.7  2002/06/17 06:33:09  relnev
  22 * ryan's struct patch for gcc 2.95
  23 *
  24 * Revision 1.6  2002/06/09 04:41:21  relnev
  25 * added copyright header
  26 *
  27 * Revision 1.5  2002/06/02 04:26:34  relnev
  28 * warning cleanup
  29 *
  30 * Revision 1.4  2002/05/26 20:32:24  theoddone33
  31 * Fix some minor stuff
  32 *
  33 * Revision 1.3  2002/05/26 20:20:54  relnev
  34 * unix.h: updated
  35 *
  36 * inetfile/: complete
  37 *
  38 * Revision 1.2  2002/05/07 03:16:45  theoddone33
  39 * The Great Newline Fix
  40 *
  41 * Revision 1.1.1.1  2002/05/03 03:28:09  root
  42 * Initial import.
  43 *
  44  *
  45  * 5     8/24/99 1:49a Dave
  46  * Fixed client-side afterburner stuttering. Added checkbox for no version
  47  * checking on PXO join. Made button info passing more friendly between
  48  * client and server.
  49  *
  50  * 4     8/22/99 1:19p Dave
  51  * Fixed up http proxy code. Cleaned up scoring code. Reverse the order in
  52  * which d3d cards are detected.
  53  *
  54  * 21    8/21/99 6:33p Kevin
  55  * Fixed Proxy Stuff
  56  *
  57  * 20    8/21/99 6:48a Jeff
  58  * Linux port
  59  *
  60  * 19    8/20/99 3:01p Kevin
  61  * Added support for Proxies (I hope!)
  62  *
  63  * 18    8/15/99 6:38p Jeff
  64  * fixed compile error
  65  *
  66  * 17    8/15/99 6:26p Kevin
  67  *
  68  * 16    4/14/99 1:20a Jeff
  69  * fixed case mismatched #includes
  70  *
  71  * 15    3/03/99 12:28a Nate
  72  * sped up something or other when the connection is done
  73  *
  74  * 14    2/03/99 4:20p Kevin
  75  * Got multiplayer working with .mn3 files, and setup autodownloading
  76  *
  77  * 13    1/27/99 5:49p Kevin
  78  *
  79  * 12    1/27/99 5:38p Kevin
  80  *
  81  * 11    12/30/98 12:15p Kevin
  82  * Auto Mission Download system
  83  *
  84  * 10    10/12/98 4:59p Kevin
  85  * Added delay to thread when cancelled...
  86  *
  87  * 9     10/12/98 4:49p Nate
  88  * More fixes
  89  *
  90  * 8     10/12/98 1:54p Nate
  91  * Fixed bug
  92  *
  93  * 7     10/12/98 11:30a Kevin
  94  * More memory stuff
  95  *
  96  * 6     10/08/98 12:59p Nate
  97  * fixed cancel
  98  *
  99  * 5     10/08/98 9:57a Kevin
 100  * made transfer cancellable
 101  *
 102  * 4     7/31/98 12:19p Nate
 103  * Fixed http abort problem.
 104  *
 105  * 3     7/31/98 11:57a Kevin
 106  * Added new functions for getting state
 107  *
 108  * 2     6/01/98 10:10a Kevin
 109  * Added DLL connection interface and auto update DLL
 110  *
 111  * 1     5/27/98 9:52a Kevin
 112  *
 113  * 1     5/25/98 5:31p Kevin
 114  * Initial version
 115 *
 116 * $NoKeywords: $
 117 */
 118
 119
 120 #ifndef PLAT_UNIX
 121 #include <windows.h>
 122 #include <process.h>
 123 #else
 124 #include <sys/types.h>
 125 #include <sys/socket.h>
 126 #include <netinet/in.h>
 127 #include <arpa/inet.h>
 128 #include <netdb.h>
 129 #include <sys/ioctl.h>
 130 #include <errno.h>
 131 #include <sys/time.h>
 132 #include <unistd.h>
 133 #endif
 134
 135 #include <string.h>
 136 #include <stdio.h>
 137 #include <stdlib.h>
 138 #include <ctype.h>
 139
 140 #include "pstypes.h"
 141 #include "inetgetfile.h"
 142 #include "chttpget.h"
 143
 144
 145
 146 #define NW_AGHBN_CANCEL         1
 147 #define NW_AGHBN_LOOKUP         2
 148 #define NW_AGHBN_READ           3
 149
 150 int http_gethostbynameworker(void *parm);
 151
 152
 153 int http_Asyncgethostbyname(unsigned int *ip,int command, char *hostname);
 154
 155 int HTTPObjThread( void * obj )
 156 {
 157         ((ChttpGet *)obj)->WorkerThread();
 158         ((ChttpGet *)obj)->m_Aborted = true;
 159
 160         return ((ChttpGet *)obj)->GetStatus();
 161 }
 162
 163 void ChttpGet::AbortGet()
 164 {
 165         m_Aborting = true;
 166         while(!m_Aborted) SDL_Delay(50); //Wait for the thread to end
 167 }
 168
 169 ChttpGet::ChttpGet(char *URL,char *localfile,char *proxyip,unsigned short proxyport)
 170 {
 171         m_ProxyEnabled = true;
 172         m_ProxyIP = proxyip;
 173         m_ProxyPort = proxyport;
 174         GetFile(URL,localfile);
 175 }
 176
 177 ChttpGet::ChttpGet(char *URL,char *localfile)
 178 {
 179         m_ProxyEnabled = false;
 180         GetFile(URL,localfile);
 181 }
 182
 183
 184 void ChttpGet::GetFile(char *URL,char *localfile)
 185 {
 186         m_DataSock = INVALID_SOCKET;
 187         m_iBytesIn = 0;
 188         m_iBytesTotal = 0;
 189         m_State = HTTP_STATE_STARTUP;;
 190         m_Aborting = false;
 191         m_Aborted = false;
 192
 193         SDL_strlcpy(m_URL, URL, SDL_arraysize(m_URL));
 194
 195         LOCALFILE = fopen(localfile,"wb");
 196         if(NULL == LOCALFILE)
 197         {
 198                 m_State = HTTP_STATE_CANT_WRITE_FILE;
 199                 m_Aborted = true;
 200                 return;
 201         }
 202         m_DataSock = socket(AF_INET, SOCK_STREAM, 0);
 203         if(INVALID_SOCKET == m_DataSock)
 204         {
 205                 m_State = HTTP_STATE_SOCKET_ERROR;
 206                 m_Aborted = true;
 207                 return;
 208         }
 209         unsigned long arg;
 210
 211         arg = true;
 212
 213         ioctlsocket( m_DataSock, FIONBIO, &arg );
 214
 215         char *pURL = URL;
 216         if(SDL_strncasecmp(URL,"http:",5)==0)
 217         {
 218                 pURL +=5;
 219                 while(*pURL == '/')
 220                 {
 221                         pURL++;
 222                 }
 223         }
 224         //There shouldn't be any : in this string
 225         if(SDL_strchr(pURL,':'))
 226         {
 227                 m_State = HTTP_STATE_URL_PARSING_ERROR;
 228                 m_Aborted = true;
 229                 return;
 230         }
 231         //read the filename by searching backwards for a /
 232         //then keep reading until you find the first /
 233         //when you found it, you have the host and dir
 234         char *filestart = NULL;
 235         char *dirstart = NULL;
 236         for(int i = strlen(pURL);i>=0;i--)
 237         {
 238                 if(pURL[i]== '/')
 239                 {
 240                         if(!filestart)
 241                         {
 242                                 filestart = pURL+i+1;
 243                                 dirstart = pURL+i+1;
 244                                 SDL_strlcpy(m_szFilename, filestart, SDL_arraysize(m_szFilename));
 245                         }
 246                         else
 247                         {
 248                                 dirstart = pURL+i+1;
 249                         }
 250                 }
 251         }
 252         if((dirstart==NULL) || (filestart==NULL))
 253         {
 254                 m_State = HTTP_STATE_URL_PARSING_ERROR;
 255                 m_Aborted = true;
 256                 return;
 257         }
 258         else
 259         {
 260                 SDL_strlcpy(m_szDir, dirstart, SDL_arraysize(m_szDir));//,(filestart-dirstart));
 261                 int len = min((dirstart-pURL), (int)SDL_arraysize(m_szHost));
 262                 SDL_strlcpy(m_szHost, pURL, len);
 263
 264         SDL_Thread *thread = SDL_CreateThread(HTTPObjThread, "HTTPObjThread", this);
 265
 266         if(thread == NULL)
 267                 m_Aborted = true;
 268         else
 269         {
 270                 int ret_val = 0;
 271                 SDL_WaitThread(thread, &ret_val);
 272         }
 273 }
 274
 275
 276 ChttpGet::~ChttpGet()
 277 {
 278         if(m_DataSock != INVALID_SOCKET)
 279         {
 280                 shutdown(m_DataSock,2);
 281                 closesocket(m_DataSock);
 282         }
 283
 284         if(LOCALFILE != NULL)
 285         {
 286                 fclose(LOCALFILE);
 287         }
 288 }
 289
 290 int ChttpGet::GetStatus()
 291 {
 292         return m_State;
 293 }
 294
 295 unsigned int ChttpGet::GetBytesIn()
 296 {
 297         return m_iBytesIn;
 298 }
 299
 300 unsigned int ChttpGet::GetTotalBytes()
 301 {
 302         return m_iBytesTotal;
 303 }
 304
 305
 306 void ChttpGet::WorkerThread()
 307 {
 308         char szCommand[1000];
 309         char *p;
 310         int irsp = 0;
 311         ConnectSocket();
 312         if(m_Aborting)
 313         {
 314                 fclose(LOCALFILE);
 315                 LOCALFILE = NULL;
 316                 return;
 317         }
 318         if(m_State != HTTP_STATE_CONNECTED)
 319         {
 320                 fclose(LOCALFILE);
 321                 LOCALFILE = NULL;
 322                 return;
 323         }
 324         SDL_snprintf(szCommand,SDL_arraysize(szCommand),"GET %s%s HTTP/1.1\nAccept: */*\nAccept-Encoding: deflate\nHost: %s\n\n\n",m_ProxyEnabled?"":"/",m_ProxyEnabled?m_URL:m_szDir,m_szHost);
 325         send(m_DataSock,szCommand,strlen(szCommand),0);
 326         p = GetHTTPLine();
 327         if(SDL_strncasecmp("HTTP/",p,5)==0)
 328         {
 329                 char *pcode;
 330                 pcode = SDL_strchr(p,' ')+1;
 331                 if(!pcode)
 332                 {
 333                         m_State = HTTP_STATE_UNKNOWN_ERROR;
 334                         fclose(LOCALFILE);
 335                         LOCALFILE = NULL;
 336                         return;
 337
 338                 }
 339                 pcode[3] = '\0';
 340                 irsp = atoi(pcode);
 341
 342                 if(irsp == 0)
 343                 {
 344                         m_State = HTTP_STATE_UNKNOWN_ERROR;
 345                         fclose(LOCALFILE);
 346                         LOCALFILE = NULL;
 347                         return;
 348                 }
 349                 if(irsp==200)
 350                 {
 351                         int idataready=0;
 352                         do
 353                         {
 354                                 p = GetHTTPLine();
 355                                 if(p==NULL)
 356                                 {
 357                                         m_State = HTTP_STATE_UNKNOWN_ERROR;
 358                                         fclose(LOCALFILE);
 359                                         LOCALFILE = NULL;
 360                                         return;
 361                                 }
 362                                 if(*p=='\0')
 363                                 {
 364                                         idataready = 1;
 365                                         break;
 366                                 }
 367                                 if(SDL_strncasecmp(p,"Content-Length:",strlen("Content-Length:"))==0)
 368                                 {
 369                                         char *s = SDL_strchr(p,' ')+1;
 370                                         p = s;
 371                                         if(s)
 372                                         {
 373                                                 while(*s)
 374                                                 {
 375                                                         if(!isdigit(*s))
 376                                                         {
 377                                                                 *s='\0';
 378                                                         }
 379                                                         s++;
 380                                                 };
 381                                                 m_iBytesTotal = atoi(p);
 382                                         }
 383
 384                                 }
 385
 386                                 SDL_Delay(1);
 387                         }while(!idataready);
 388                 ReadDataChannel();
 389                 return;
 390                 }
 391                 m_State = HTTP_STATE_FILE_NOT_FOUND;
 392                 fclose(LOCALFILE);
 393                 LOCALFILE = NULL;
 394                 return;
 395         }
 396         else
 397         {
 398                 m_State = HTTP_STATE_UNKNOWN_ERROR;
 399                 fclose(LOCALFILE);
 400                 LOCALFILE = NULL;
 401                 return;
 402         }
 403 }
 404
 405 int ChttpGet::ConnectSocket()
 406 {
 407         unsigned int ip;
 408         struct servent *se;
 409         struct sockaddr_in hostaddr;
 410         if(m_Aborting){
 411                 return 0;
 412         }
 413
 414         ip = inet_addr((const char *)m_szHost);
 415
 416         int rcode = 0;
 417         if(ip==INADDR_NONE)
 418         {
 419                 http_Asyncgethostbyname(&ip,NW_AGHBN_LOOKUP,m_szHost);
 420                 do
 421                 {
 422                         if(m_Aborting)
 423                         {
 424                                 http_Asyncgethostbyname(&ip,NW_AGHBN_CANCEL,m_szHost);
 425                                 return 0;
 426                         }
 427                         rcode = http_Asyncgethostbyname(&ip,NW_AGHBN_READ,m_szHost);
 428
 429                         SDL_Delay(1);
 430                 }while(rcode==0);
 431         }
 432
 433         if(rcode == -1)
 434         {
 435                 m_State = HTTP_STATE_HOST_NOT_FOUND;
 436                 return 0;
 437         }
 438         //m_ControlSock
 439         if(m_Aborting)
 440                 return 0;
 441         se = getservbyname("http", NULL);
 442         if(m_Aborting)
 443                 return 0;
 444         if(se == NULL)
 445         {
 446                 hostaddr.sin_port = htons(80);
 447         }
 448         else
 449         {
 450                 hostaddr.sin_port = se->s_port;
 451         }
 452         hostaddr.sin_family = AF_INET;
 453         //ip = htonl(ip);
 454         memcpy(&hostaddr.sin_addr,&ip,4);
 455
 456         if(m_ProxyEnabled)
 457         {
 458                 //This is on a proxy, so we need to make sure to connect to the proxy machine
 459                 ip = inet_addr((const char *)m_ProxyIP);
 460
 461                 if(ip==INADDR_NONE)
 462                 {
 463                         http_Asyncgethostbyname(&ip,NW_AGHBN_LOOKUP,m_ProxyIP);
 464                         rcode = 0;
 465                         do
 466                         {
 467                                 if(m_Aborting)
 468                                 {
 469                                         http_Asyncgethostbyname(&ip,NW_AGHBN_CANCEL,m_ProxyIP);
 470                                         return 0;
 471                                 }
 472                                 rcode = http_Asyncgethostbyname(&ip,NW_AGHBN_READ,m_ProxyIP);
 473
 474                                 SDL_Delay(1);
 475                         }while(rcode==0);
 476
 477
 478                         if(rcode == -1)
 479                         {
 480                                 m_State = HTTP_STATE_HOST_NOT_FOUND;
 481                                 return 0;
 482                         }
 483
 484                 }
 485                 //Use either the proxy port or 80 if none specified
 486                 hostaddr.sin_port = htons((ushort)(m_ProxyPort ? m_ProxyPort : 80));
 487                 //Copy the proxy address...
 488                 memcpy(&hostaddr.sin_addr,&ip,4);
 489
 490         }
 491         //Now we will connect to the host
 492         fd_set  wfds;
 493
 494         timeval timeout;
 495         timeout.tv_sec = 0;
 496         timeout.tv_usec = 0;
 497         int serr = connect(m_DataSock, (struct sockaddr *)&hostaddr, sizeof(struct sockaddr));
 498         int cerr = WSAGetLastError();
 499         if(serr)
 500         {
 501                 while((cerr==WSAEALREADY)||(cerr==WSAEINVAL)||(cerr==WSAEWOULDBLOCK))
 502                 {
 503                         FD_ZERO(&wfds);
 504                         FD_SET( m_DataSock, &wfds );
 505                         if(select(0,NULL,&wfds,NULL,&timeout))
 506                         {
 507                                 serr = 0;
 508                                 break;
 509                         }
 510                         if(m_Aborting)
 511                                 return 0;
 512                         serr = connect(m_DataSock, (struct sockaddr *)&hostaddr, sizeof(struct sockaddr));
 513                         if(serr == 0)
 514                                 break;
 515                         cerr = WSAGetLastError();
 516                         if(cerr==WSAEISCONN)
 517                         {
 518                                 serr = 0;
 519                                 break;
 520                         }
 521
 522                         SDL_Delay(1);
 523                 };
 524         }
 525         if(serr)
 526         {
 527                 m_State = HTTP_STATE_CANT_CONNECT;
 528                 return 0;
 529         }
 530         m_State = HTTP_STATE_CONNECTED;
 531         return 1;
 532 }
 533
 534 char *ChttpGet::GetHTTPLine()
 535 {
 536         int iBytesRead;
 537         char chunk[2];
 538         unsigned int igotcrlf = 0;
 539         memset(recv_buffer,0,1000);
 540         do
 541         {
 542                 chunk[0]='\0';
 543                 bool gotdata = false;
 544                 do
 545                 {
 546                         iBytesRead = recv(m_DataSock,chunk,1,0);
 547
 548                         if(SOCKET_ERROR == iBytesRead)
 549                         {
 550                                 int error = WSAGetLastError();
 551                                 if(WSAEWOULDBLOCK==error)
 552                                 {
 553                                         gotdata = false;
 554                                         continue;
 555                                 }
 556                                 else
 557                                         return NULL;
 558                         }
 559                         else
 560                         {
 561                                 gotdata = true;
 562                         }
 563
 564                         SDL_Delay(1);
 565                 }while(!gotdata);
 566
 567                 if(chunk[0]==0x0d)
 568                 {
 569                         //This should always read a 0x0a
 570                         do
 571                         {
 572                                 iBytesRead = recv(m_DataSock,chunk,1,0);
 573
 574                                 if(SOCKET_ERROR == iBytesRead)
 575                                 {
 576                                         int error = WSAGetLastError();
 577                                         if(WSAEWOULDBLOCK==error)
 578                                         {
 579                                                 gotdata = false;
 580                                                 continue;
 581                                         }
 582                                         else
 583                                                 return NULL;
 584                                 }
 585                                 else
 586                                 {
 587                                         gotdata = true;
 588                                 }
 589
 590                                 SDL_Delay(1);
 591                         }while(!gotdata);
 592                         igotcrlf = 1;
 593                 }
 594                 else
 595                 {       chunk[1] = '\0';
 596                         SDL_strlcat(recv_buffer, chunk, SDL_arraysize(recv_buffer));
 597                 }
 598
 599                 SDL_Delay(1);
 600         }while(igotcrlf==0);
 601         return recv_buffer;
 602 }
 603
 604 unsigned int ChttpGet::ReadDataChannel()
 605 {
 606         char sDataBuffer[4096];         // Data-storage buffer for the data channel
 607         int nBytesRecv = 0;                                             // Bytes received from the data channel
 608
 609         fd_set  wfds;
 610
 611         timeval timeout;
 612         timeout.tv_sec = 0;
 613         timeout.tv_usec = 500;
 614
 615         m_State = HTTP_STATE_RECEIVING;
 616    do
 617    {
 618                 FD_ZERO(&wfds);
 619                 FD_SET( m_DataSock, &wfds );
 620
 621                 if((m_iBytesTotal)&&(m_iBytesIn==m_iBytesTotal))
 622                 {
 623                         break;
 624                 }
 625                 select(0,&wfds,NULL,NULL,&timeout);
 626         if(m_Aborting)
 627                 {
 628                         fclose(LOCALFILE);
 629                         return 0;
 630                 }
 631                 nBytesRecv = recv(m_DataSock, (char *)&sDataBuffer,sizeof(sDataBuffer), 0);
 632         if(m_Aborting)
 633                 {
 634                         fclose(LOCALFILE);
 635                         return 0;
 636                 }
 637                 if(SOCKET_ERROR == nBytesRecv)
 638                 {
 639                         int error = WSAGetLastError();
 640                         if(WSAEWOULDBLOCK==error)
 641                         {
 642                                 nBytesRecv = 1;
 643                                 continue;
 644                         }
 645                 }
 646                 m_iBytesIn += nBytesRecv;
 647                 if (nBytesRecv > 0 )
 648                 {
 649                         fwrite(sDataBuffer,nBytesRecv,1,LOCALFILE);
 650                         //Write sDataBuffer, nBytesRecv
 651         }
 652
 653                 SDL_Delay(1);
 654         }while (nBytesRecv > 0);
 655         fclose(LOCALFILE);
 656         // Close the file and check for error returns.
 657         if (nBytesRecv == SOCKET_ERROR)
 658         {
 659                 //Ok, we got a socket error -- xfer aborted?
 660                 m_State = HTTP_STATE_RECV_FAILED;
 661                 return 0;
 662         }
 663         else
 664         {
 665                 //OutputDebugString("HTTP File complete!\n");
 666                 //done!
 667                 m_State = HTTP_STATE_FILE_RECEIVED;
 668                 return 1;
 669         }
 670 }
 671
 672
 673 typedef struct _async_dns_lookup
 674 {
 675         unsigned int ip;        //resolved host. Write only to worker thread.
 676         char * host;//host name to resolve. read only to worker thread
 677         bool done;      //write only to the worker thread. Signals that the operation is complete
 678         bool error; //write only to worker thread. Thread sets this if the name doesn't resolve
 679         bool abort;     //read only to worker thread. If this is set, don't fill in the struct.
 680 }async_dns_lookup;
 681
 682 async_dns_lookup httpaslu;
 683 async_dns_lookup *http_lastaslu = NULL;
 684
 685 int http_gethostbynameworker(void *parm);
 686
 687 int http_Asyncgethostbyname(unsigned int *ip,int command, char *hostname)
 688 {
 689
 690         if(command==NW_AGHBN_LOOKUP)
 691         {
 692                 if(http_lastaslu)
 693                         http_lastaslu->abort = true;
 694
 695                 async_dns_lookup *newaslu;
 696                 newaslu = (async_dns_lookup *)malloc(sizeof(async_dns_lookup));
 697                 memset(&newaslu->ip,0,sizeof(unsigned int));
 698                 newaslu->host = hostname;
 699                 newaslu->done = false;
 700                 newaslu->error = false;
 701                 newaslu->abort = false;
 702                 http_lastaslu = newaslu;
 703                 httpaslu.done = false;
 704
 705                 SDL_CreateThread(http_gethostbynameworker, "GetHostByNameWorker", newaslu);
 706
 707                 return 1;
 708         }
 709         else if(command==NW_AGHBN_CANCEL)
 710         {
 711                 if(http_lastaslu)
 712                         http_lastaslu->abort = true;
 713                 http_lastaslu = NULL;
 714         }
 715         else if(command==NW_AGHBN_READ)
 716         {
 717                 if(!http_lastaslu)
 718                         return -1;
 719                 if(httpaslu.done)
 720                 {
 721                         //free(http_lastaslu);
 722                         http_lastaslu = NULL;
 723                         memcpy(ip,&httpaslu.ip,sizeof(unsigned int));
 724                         return 1;
 725                 }
 726                 else if(httpaslu.error)
 727                 {
 728                         free(http_lastaslu);
 729                         http_lastaslu = NULL;
 730                         return -1;
 731                 }
 732                 else return 0;
 733         }
 734         return -2;
 735
 736 }
 737
 738 // This is the worker thread which does the lookup.
 739 int http_gethostbynameworker(void *parm)
 740 {
 741         async_dns_lookup *lookup = (async_dns_lookup *)parm;
 742         struct hostent *he = gethostbyname(lookup->host);
 743         if(he==NULL)
 744         {
 745                 lookup->error = true;
 746                 return 1;
 747         }
 748         else if(!lookup->abort)
 749         {
 750                 memcpy(&lookup->ip,he->h_addr_list[0],sizeof(unsigned int));
 751                 lookup->done = true;
 752                 memcpy(&httpaslu,lookup,sizeof(async_dns_lookup));
 753         }
 754         free(lookup);
 755
 756         return 0;
 757 }