src/common/ftp.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        ftp.cpp
   3 // Purpose:     FTP protocol
   4 // Author:      Guilhem Lavaux
   5 // Modified by: Mark Johnson, wxWindows@mj10777.de
   6 //              20000917 : RmDir, GetLastResult, GetList
   7 //              Vadim Zeitlin (numerous fixes and rewrites to all part of the
   8 //              code, support ASCII/Binary modes, better error reporting, more
   9 //              robust Abort(), support for arbitrary FTP commands, ...)
  10 // Created:     07/07/1997
  11 // RCS-ID:      $Id$
  12 // Copyright:   (c) 1997, 1998 Guilhem Lavaux
  13 // Licence:     wxWindows licence
  14 /////////////////////////////////////////////////////////////////////////////
  15
  16 // ============================================================================
  17 // declarations
  18 // ============================================================================
  19
  20 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  21   #pragma implementation "ftp.h"
  22 #endif
  23
  24 // ----------------------------------------------------------------------------
  25 // headers
  26 // ----------------------------------------------------------------------------
  27
  28 // For compilers that support precompilation, includes "wx.h".
  29 #include "wx/wxprec.h"
  30
  31 #ifdef __BORLANDC__
  32   #pragma hdrstop
  33 #endif
  34
  35 #if wxUSE_PROTOCOL_FTP
  36
  37 #ifndef WX_PRECOMP
  38     #include <stdlib.h>
  39     #include "wx/string.h"
  40     #include "wx/utils.h"
  41     #include "wx/log.h"
  42     #include "wx/intl.h"
  43 #endif // WX_PRECOMP
  44
  45 #include "wx/sckaddr.h"
  46 #include "wx/socket.h"
  47 #include "wx/url.h"
  48 #include "wx/sckstrm.h"
  49 #include "wx/protocol/protocol.h"
  50 #include "wx/protocol/ftp.h"
  51
  52 #if defined(__WXMAC__)
  53     #include "wx/mac/macsock.h"
  54 #endif
  55
  56 #ifndef __MWERKS__
  57     #include <memory.h>
  58 #endif
  59
  60 // ----------------------------------------------------------------------------
  61 // constants
  62 // ----------------------------------------------------------------------------
  63
  64 // the length of FTP status code (3 digits)
  65 static const size_t LEN_CODE = 3;
  66
  67 // ----------------------------------------------------------------------------
  68 // macros
  69 // ----------------------------------------------------------------------------
  70
  71 IMPLEMENT_DYNAMIC_CLASS(wxFTP, wxProtocol)
  72 IMPLEMENT_PROTOCOL(wxFTP, wxT("ftp"), wxT("ftp"), TRUE)
  73
  74 // ============================================================================
  75 // implementation
  76 // ============================================================================
  77
  78 // ----------------------------------------------------------------------------
  79 // wxFTP constructor and destructor
  80 // ----------------------------------------------------------------------------
  81
  82 wxFTP::wxFTP()
  83 {
  84     m_lastError = wxPROTO_NOERR;
  85     m_streaming = FALSE;
  86     m_currentTransfermode = NONE;
  87
  88     m_user = wxT("anonymous");
  89     m_passwd << wxGetUserId() << wxT('@') << wxGetFullHostName();
  90
  91     SetNotify(0);
  92     SetFlags(wxSOCKET_NONE);
  93 }
  94
  95 wxFTP::~wxFTP()
  96 {
  97     if ( m_streaming )
  98     {
  99         (void)Abort();
 100     }
 101
 102     Close();
 103 }
 104
 105 // ----------------------------------------------------------------------------
 106 // wxFTP connect and login methods
 107 // ----------------------------------------------------------------------------
 108
 109 bool wxFTP::Connect(wxSockAddress& addr, bool WXUNUSED(wait))
 110 {
 111     if ( !wxProtocol::Connect(addr) )
 112     {
 113         m_lastError = wxPROTO_NETERR;
 114         return FALSE;
 115     }
 116
 117     if ( !m_user )
 118     {
 119         m_lastError = wxPROTO_CONNERR;
 120         return FALSE;
 121     }
 122
 123     // we should have 220 welcome message
 124     if ( !CheckResult('2') )
 125     {
 126         Close();
 127         return FALSE;
 128     }
 129
 130     wxString command;
 131     command.Printf(wxT("USER %s"), m_user.c_str());
 132     char rc = SendCommand(command);
 133     if ( rc == '2' )
 134     {
 135         // 230 return: user accepted without password
 136         return TRUE;
 137     }
 138
 139     if ( rc != '3' )
 140     {
 141         Close();
 142         return FALSE;
 143     }
 144
 145     command.Printf(wxT("PASS %s"), m_passwd.c_str());
 146     if ( !CheckCommand(command, '2') )
 147     {
 148         Close();
 149         return FALSE;
 150     }
 151
 152     return TRUE;
 153 }
 154
 155 bool wxFTP::Connect(const wxString& host)
 156 {
 157     wxIPV4address addr;
 158     addr.Hostname(host);
 159     addr.Service(wxT("ftp"));
 160
 161     return Connect(addr);
 162 }
 163
 164 bool wxFTP::Close()
 165 {
 166     if ( m_streaming )
 167     {
 168         m_lastError = wxPROTO_STREAMING;
 169         return FALSE;
 170     }
 171
 172     if ( IsConnected() )
 173     {
 174         if ( !CheckCommand(wxT("QUIT"), '2') )
 175         {
 176             wxLogDebug(_T("Failed to close connection gracefully."));
 177         }
 178     }
 179
 180     return wxSocketClient::Close();
 181 }
 182
 183 // ============================================================================
 184 // low level methods
 185 // ============================================================================
 186
 187 // ----------------------------------------------------------------------------
 188 // Send command to FTP server
 189 // ----------------------------------------------------------------------------
 190
 191 char wxFTP::SendCommand(const wxString& command)
 192 {
 193     if ( m_streaming )
 194     {
 195         m_lastError = wxPROTO_STREAMING;
 196         return 0;
 197     }
 198
 199     wxString tmp_str = command + wxT("\r\n");
 200     const wxWX2MBbuf tmp_buf = tmp_str.mb_str();
 201     if ( Write(wxMBSTRINGCAST tmp_buf, strlen(tmp_buf)).Error())
 202     {
 203         m_lastError = wxPROTO_NETERR;
 204         return 0;
 205     }
 206
 207 #ifdef __WXDEBUG__
 208     // don't show the passwords in the logs (even in debug ones)
 209     wxString cmd, password;
 210     if ( command.Upper().StartsWith(_T("PASS "), &password) )
 211     {
 212         cmd << _T("PASS ") << wxString(_T('*'), password.length());
 213     }
 214     else
 215     {
 216         cmd = command;
 217     }
 218
 219     wxLogTrace(FTP_TRACE_MASK, _T("==> %s"), cmd.c_str());
 220 #endif // __WXDEBUG__
 221
 222     return GetResult();
 223 }
 224
 225 // ----------------------------------------------------------------------------
 226 // Recieve servers reply
 227 // ----------------------------------------------------------------------------
 228
 229 char wxFTP::GetResult()
 230 {
 231     wxString code;
 232
 233     // m_lastResult will contain the entire server response, possibly on
 234     // multiple lines
 235     m_lastResult.clear();
 236
 237     // we handle multiline replies here according to RFC 959: it says that a
 238     // reply may either be on 1 line of the form "xyz ..." or on several lines
 239     // in whuch case it looks like
 240     //      xyz-...
 241     //      ...
 242     //      xyz ...
 243     // and the intermeidate lines may start with xyz or not
 244     bool badReply = FALSE;
 245     bool firstLine = TRUE;
 246     bool endOfReply = FALSE;
 247     while ( !endOfReply && !badReply )
 248     {
 249         wxString line;
 250         m_lastError = ReadLine(line);
 251         if ( m_lastError )
 252             return 0;
 253
 254         if ( !m_lastResult.empty() )
 255         {
 256             // separate from last line
 257             m_lastResult += _T('\n');
 258         }
 259
 260         m_lastResult += line;
 261
 262         // unless this is an intermediate line of a multiline reply, it must
 263         // contain the code in the beginning and '-' or ' ' following it
 264         if ( line.Len() < LEN_CODE + 1 )
 265         {
 266             if ( firstLine )
 267             {
 268                 badReply = TRUE;
 269             }
 270             else
 271             {
 272                 wxLogTrace(FTP_TRACE_MASK, _T("<== %s %s"),
 273                            code.c_str(), line.c_str());
 274             }
 275         }
 276         else // line has at least 4 chars
 277         {
 278             // this is the char which tells us what we're dealing with
 279             wxChar chMarker = line.GetChar(LEN_CODE);
 280
 281             if ( firstLine )
 282             {
 283                 code = wxString(line, LEN_CODE);
 284                 wxLogTrace(FTP_TRACE_MASK, _T("<== %s %s"),
 285                            code.c_str(), line.c_str() + LEN_CODE + 1);
 286
 287                 switch ( chMarker )
 288                 {
 289                     case _T(' '):
 290                         endOfReply = TRUE;
 291                         break;
 292
 293                     case _T('-'):
 294                         firstLine = FALSE;
 295                         break;
 296
 297                     default:
 298                         // unexpected
 299                         badReply = TRUE;
 300                 }
 301             }
 302             else // subsequent line of multiline reply
 303             {
 304                 if ( wxStrncmp(line, code, LEN_CODE) == 0 )
 305                 {
 306                     if ( chMarker == _T(' ') )
 307                     {
 308                         endOfReply = TRUE;
 309                     }
 310
 311                     wxLogTrace(FTP_TRACE_MASK, _T("<== %s %s"),
 312                                code.c_str(), line.c_str() + LEN_CODE + 1);
 313                 }
 314                 else
 315                 {
 316                     // just part of reply
 317                     wxLogTrace(FTP_TRACE_MASK, _T("<== %s %s"),
 318                                code.c_str(), line.c_str());
 319                 }
 320             }
 321         }
 322     }
 323
 324     if ( badReply )
 325     {
 326         wxLogDebug(_T("Broken FTP server: '%s' is not a valid reply."),
 327                    m_lastResult.c_str());
 328
 329         m_lastError = wxPROTO_PROTERR;
 330
 331         return 0;
 332     }
 333
 334     // if we got here we must have a non empty code string
 335     return code[0u];
 336 }
 337
 338 // ----------------------------------------------------------------------------
 339 // wxFTP simple commands
 340 // ----------------------------------------------------------------------------
 341
 342 bool wxFTP::SetTransferMode(TransferMode transferMode)
 343 {
 344     if ( transferMode == m_currentTransfermode )
 345     {
 346         // nothing to do
 347         return TRUE;
 348     }
 349
 350     wxString mode;
 351     switch ( transferMode )
 352     {
 353         default:
 354             wxFAIL_MSG(_T("unknown FTP transfer mode"));
 355             // fall through
 356
 357         case BINARY:
 358             mode = _T('I');
 359             break;
 360
 361         case ASCII:
 362             mode = _T('A');
 363             break;
 364     }
 365
 366     if ( !DoSimpleCommand(_T("TYPE"), mode) )
 367     {
 368         wxLogError(_("Failed to set FTP transfer mode to %s."), (const wxChar*)
 369                    (transferMode == ASCII ? _("ASCII") : _("binary")));
 370
 371         return FALSE;
 372     }
 373
 374     // If we get here the operation has been succesfully completed
 375     // Set the status-member
 376     m_currentTransfermode = transferMode;
 377
 378     return TRUE;
 379 }
 380
 381 bool wxFTP::DoSimpleCommand(const wxChar *command, const wxString& arg)
 382 {
 383     wxString fullcmd = command;
 384     if ( !arg.empty() )
 385     {
 386         fullcmd << _T(' ') << arg;
 387     }
 388
 389     if ( !CheckCommand(fullcmd, '2') )
 390     {
 391         wxLogDebug(_T("FTP command '%s' failed."), fullcmd.c_str());
 392
 393         return FALSE;
 394     }
 395
 396     return TRUE;
 397 }
 398
 399 bool wxFTP::ChDir(const wxString& dir)
 400 {
 401     // some servers might not understand ".." if they use different directory
 402     // tree conventions, but they always understand CDUP - should we use it if
 403     // dir == ".."? OTOH, do such servers (still) exist?
 404
 405     return DoSimpleCommand(_T("CWD"), dir);
 406 }
 407
 408 bool wxFTP::MkDir(const wxString& dir)
 409 {
 410     return DoSimpleCommand(_T("MKD"), dir);
 411 }
 412
 413 bool wxFTP::RmDir(const wxString& dir)
 414 {
 415     return DoSimpleCommand(_T("RMD"), dir);
 416 }
 417
 418 wxString wxFTP::Pwd()
 419 {
 420     wxString path;
 421
 422     if ( CheckCommand(wxT("PWD"), '2') )
 423     {
 424         // the result is at least that long if CheckCommand() succeeded
 425         const wxChar *p = m_lastResult.c_str() + LEN_CODE + 1;
 426         if ( *p != _T('"') )
 427         {
 428             wxLogDebug(_T("Missing starting quote in reply for PWD: %s"), p);
 429         }
 430         else
 431         {
 432             for ( p++; *p; p++ )
 433             {
 434                 if ( *p == _T('"') )
 435                 {
 436                     // check if the quote is doubled
 437                     p++;
 438                     if ( !*p || *p != _T('"') )
 439                     {
 440                         // no, this is the end
 441                         break;
 442                     }
 443                     //else: yes, it is: this is an embedded quote in the
 444                     //      filename, treat as normal char
 445                 }
 446
 447                 path += *p;
 448             }
 449
 450             if ( !*p )
 451             {
 452                 wxLogDebug(_T("Missing ending quote in reply for PWD: %s"),
 453                            m_lastResult.c_str() + LEN_CODE + 1);
 454             }
 455         }
 456     }
 457     else
 458     {
 459         wxLogDebug(_T("FTP PWD command failed."));
 460     }
 461
 462     return path;
 463 }
 464
 465 bool wxFTP::Rename(const wxString& src, const wxString& dst)
 466 {
 467     wxString str;
 468
 469     str = wxT("RNFR ") + src;
 470     if ( !CheckCommand(str, '3') )
 471         return FALSE;
 472
 473     str = wxT("RNTO ") + dst;
 474
 475     return CheckCommand(str, '2');
 476 }
 477
 478 bool wxFTP::RmFile(const wxString& path)
 479 {
 480     wxString str;
 481     str = wxT("DELE ") + path;
 482
 483     return CheckCommand(str, '2');
 484 }
 485
 486 // ----------------------------------------------------------------------------
 487 // wxFTP download and upload
 488 // ----------------------------------------------------------------------------
 489
 490 class wxInputFTPStream : public wxSocketInputStream
 491 {
 492 public:
 493     wxInputFTPStream(wxFTP *ftp, wxSocketBase *sock)
 494         : wxSocketInputStream(*sock)
 495     {
 496         m_ftp = ftp;
 497
 498         // FIXME make the timeout configurable
 499
 500         // set a shorter than default timeout
 501         m_i_socket->SetTimeout(60); // 1 minute
 502     }
 503
 504     size_t GetSize() const { return m_ftpsize; }
 505
 506     virtual ~wxInputFTPStream()
 507     {
 508         delete m_i_socket;
 509
 510         if ( IsOk() )
 511         {
 512             // wait for "226 transfer completed"
 513             m_ftp->CheckResult('2');
 514
 515             m_ftp->m_streaming = FALSE;
 516         }
 517         else
 518         {
 519             m_ftp->Abort();
 520         }
 521
 522         // delete m_i_socket; // moved to top of destructor to accomodate wu-FTPd >= 2.6.0
 523     }
 524
 525     wxFTP *m_ftp;
 526     size_t m_ftpsize;
 527
 528     DECLARE_NO_COPY_CLASS(wxInputFTPStream)
 529 };
 530
 531 class wxOutputFTPStream : public wxSocketOutputStream
 532 {
 533 public:
 534     wxOutputFTPStream(wxFTP *ftp_clt, wxSocketBase *sock)
 535         : wxSocketOutputStream(*sock), m_ftp(ftp_clt)
 536     {
 537     }
 538
 539     virtual ~wxOutputFTPStream(void)
 540     {
 541         if ( IsOk() )
 542         {
 543             // close data connection first, this will generate "transfer
 544             // completed" reply
 545             delete m_o_socket;
 546
 547             // read this reply
 548             m_ftp->CheckResult('2');
 549
 550             m_ftp->m_streaming = FALSE;
 551         }
 552         else
 553         {
 554             // abort data connection first
 555             m_ftp->Abort();
 556
 557             // and close it after
 558             delete m_o_socket;
 559         }
 560     }
 561
 562     wxFTP *m_ftp;
 563
 564     DECLARE_NO_COPY_CLASS(wxOutputFTPStream)
 565 };
 566
 567 wxSocketClient *wxFTP::GetPort()
 568 {
 569     int a[6];
 570
 571     if ( !DoSimpleCommand(_T("PASV")) )
 572     {
 573         wxLogError(_("The FTP server doesn't support passive mode."));
 574
 575         return NULL;
 576     }
 577
 578     const wxChar *addrStart = wxStrchr(m_lastResult, _T('('));
 579     if ( !addrStart )
 580     {
 581         m_lastError = wxPROTO_PROTERR;
 582
 583         return NULL;
 584     }
 585
 586     const wxChar *addrEnd = wxStrchr(addrStart, _T(')'));
 587     if ( !addrEnd )
 588     {
 589         m_lastError = wxPROTO_PROTERR;
 590
 591         return NULL;
 592     }
 593
 594     wxString straddr(addrStart + 1, addrEnd);
 595
 596     wxSscanf(straddr, wxT("%d,%d,%d,%d,%d,%d"),
 597              &a[2],&a[3],&a[4],&a[5],&a[0],&a[1]);
 598
 599     wxUint32 hostaddr = (wxUint16)a[2] << 24 |
 600                         (wxUint16)a[3] << 16 |
 601                         (wxUint16)a[4] << 8 |
 602                         a[5];
 603     wxUint16 port = (wxUint16)a[0] << 8 | a[1];
 604
 605     wxIPV4address addr;
 606     addr.Hostname(hostaddr);
 607     addr.Service(port);
 608
 609     wxSocketClient *client = new wxSocketClient();
 610     if ( !client->Connect(addr) )
 611     {
 612         delete client;
 613         return NULL;
 614     }
 615
 616     client->Notify(FALSE);
 617
 618     return client;
 619 }
 620
 621 bool wxFTP::Abort()
 622 {
 623     if ( !m_streaming )
 624         return TRUE;
 625
 626     m_streaming = FALSE;
 627     if ( !CheckCommand(wxT("ABOR"), '4') )
 628         return FALSE;
 629
 630     return CheckResult('2');
 631 }
 632
 633 wxInputStream *wxFTP::GetInputStream(const wxString& path)
 634 {
 635     int pos_size;
 636     wxInputFTPStream *in_stream;
 637
 638     if ( ( m_currentTransfermode == NONE ) && !SetTransferMode(BINARY) )
 639         return NULL;
 640
 641     wxSocketClient *sock = GetPort();
 642
 643     if ( !sock )
 644     {
 645         m_lastError = wxPROTO_NETERR;
 646         return NULL;
 647     }
 648
 649     wxString tmp_str = wxT("RETR ") + wxURL::ConvertFromURI(path);
 650     if ( !CheckCommand(tmp_str, '1') )
 651         return NULL;
 652
 653     m_streaming = TRUE;
 654
 655     in_stream = new wxInputFTPStream(this, sock);
 656
 657     pos_size = m_lastResult.Index(wxT('('));
 658     if ( pos_size != wxNOT_FOUND )
 659     {
 660         wxString str_size = m_lastResult(pos_size+1, m_lastResult.Index(wxT(')'))-1);
 661
 662         in_stream->m_ftpsize = wxAtoi(WXSTRINGCAST str_size);
 663     }
 664
 665     sock->SetFlags(wxSOCKET_WAITALL);
 666
 667     return in_stream;
 668 }
 669
 670 wxOutputStream *wxFTP::GetOutputStream(const wxString& path)
 671 {
 672     if ( ( m_currentTransfermode == NONE ) && !SetTransferMode(BINARY) )
 673         return NULL;
 674
 675     wxSocketClient *sock = GetPort();
 676
 677     wxString tmp_str = wxT("STOR ") + path;
 678     if ( !CheckCommand(tmp_str, '1') )
 679         return NULL;
 680
 681     m_streaming = TRUE;
 682
 683     return new wxOutputFTPStream(this, sock);
 684 }
 685
 686 // ----------------------------------------------------------------------------
 687 // FTP directory listing
 688 // ----------------------------------------------------------------------------
 689
 690 bool wxFTP::GetList(wxArrayString& files,
 691                     const wxString& wildcard,
 692                     bool details)
 693 {
 694     wxSocketBase *sock = GetPort();
 695     if (!sock)
 696         return FALSE;
 697
 698     // NLST : List of Filenames (including Directory's !)
 699     // LIST : depending on BS of FTP-Server
 700     //        - Unix    : result like "ls" command
 701     //        - Windows : like "dir" command
 702     //        - others  : ?
 703     wxString line(details ? _T("LIST") : _T("NLST"));
 704     if ( !!wildcard )
 705     {
 706         line << _T(' ') << wildcard;
 707     }
 708
 709     if (!CheckCommand(line, '1'))
 710     {
 711         return FALSE;
 712     }
 713     files.Empty();
 714     while ( ReadLine(sock, line) == wxPROTO_NOERR )
 715     {
 716         files.Add(line);
 717     }
 718     delete sock;
 719
 720     // the file list should be terminated by "226 Transfer complete""
 721     if ( !CheckResult('2') )
 722         return FALSE;
 723
 724     return TRUE;
 725 }
 726
 727 bool wxFTP::FileExists(const wxString& fileName)
 728 {
 729     // This function checks if the file specified in fileName exists in the
 730     // current dir. It does so by simply doing an NLST (via GetList).
 731     // If this succeeds (and the list is not empty) the file exists.
 732
 733     bool retval = FALSE;
 734     wxArrayString fileList;
 735
 736     if ( GetList(fileList, fileName, FALSE) )
 737     {
 738         // Some ftp-servers (Ipswitch WS_FTP Server 1.0.5 does this)
 739         // displays this behaviour when queried on a non-existing file:
 740         // NLST this_file_does_not_exist
 741         // 150 Opening ASCII data connection for directory listing
 742         // (no data transferred)
 743         // 226 Transfer complete
 744         // Here wxFTP::GetList(...) will succeed but it will return an empty
 745         // list.
 746         retval = !fileList.IsEmpty();
 747     }
 748
 749     return retval;
 750 }
 751
 752 // ----------------------------------------------------------------------------
 753 // FTP GetSize
 754 // ----------------------------------------------------------------------------
 755
 756 int wxFTP::GetFileSize(const wxString& fileName)
 757 {
 758     // return the filesize of the given file if possible
 759     // return -1 otherwise (predominantly if file doesn't exist
 760     // in current dir)
 761
 762     int filesize = -1;
 763
 764     // Check for existance of file via wxFTP::FileExists(...)
 765     if ( FileExists(fileName) )
 766     {
 767         wxString command;
 768
 769         // First try "SIZE" command using BINARY(IMAGE) transfermode
 770         // Especially UNIX ftp-servers distinguish between the different
 771         // transfermodes and reports different filesizes accordingly.
 772         // The BINARY size is the interesting one: How much memory
 773         // will we need to hold this file?
 774         TransferMode oldTransfermode = m_currentTransfermode;
 775         SetTransferMode(BINARY);
 776         command << _T("SIZE ") << fileName;
 777
 778         bool ok = CheckCommand(command, '2');
 779
 780         if ( ok )
 781         {
 782             // The answer should be one line: "213 <filesize>\n"
 783             // 213 is File Status (STD9)
 784             // "SIZE" is not described anywhere..? It works on most servers
 785             int statuscode;
 786             if ( wxSscanf(GetLastResult().c_str(), _T("%i %i"),
 787                           &statuscode, &filesize) == 2 )
 788             {
 789                 // We've gotten a good reply.
 790                 ok = TRUE;
 791             }
 792             else
 793             {
 794                 // Something bad happened.. A "2yz" reply with no size
 795                 // Fallback
 796                 ok = FALSE;
 797             }
 798         }
 799
 800         // Set transfermode back to the original. Only the "SIZE"-command
 801         // is dependant on transfermode
 802         if ( oldTransfermode != NONE )
 803         {
 804             SetTransferMode(oldTransfermode);
 805         }
 806
 807         // this is not a direct else clause.. The size command might return an
 808         // invalid "2yz" reply
 809         if ( !ok )
 810         {
 811             // The server didn't understand the "SIZE"-command or it
 812             // returned an invalid reply.
 813             // We now try to get details for the file with a "LIST"-command
 814             // and then parse the output from there..
 815             wxArrayString fileList;
 816             if ( GetList(fileList, fileName, TRUE) )
 817             {
 818                 if ( !fileList.IsEmpty() )
 819                 {
 820                     // We _should_ only get one line in return, but just to be
 821                     // safe we run through the line(s) returned and look for a
 822                     // substring containing the name we are looking for. We
 823                     // stop the iteration at the first occurrence of the
 824                     // filename. The search is not case-sensitive.
 825                     bool foundIt = FALSE;
 826
 827                     size_t i;
 828                     for ( i = 0; !foundIt && i < fileList.Count(); i++ )
 829                     {
 830                         foundIt = fileList[i].Upper().Contains(fileName.Upper());
 831                     }
 832
 833                     if ( foundIt )
 834                     {
 835                         // The index i points to the first occurrence of
 836                         // fileName in the array Now we have to find out what
 837                         // format the LIST has returned. There are two
 838                         // "schools": Unix-like
 839                         //
 840                         // '-rw-rw-rw- owner group size month day time filename'
 841                         //
 842                         // or Windows-like
 843                         //
 844                         // 'date size filename'
 845
 846                         // check if the first character is '-'. This would
 847                         // indicate Unix-style (this also limits this function
 848                         // to searching for files, not directories)
 849                         if ( fileList[i].Mid(0, 1) == _T("-") )
 850                         {
 851
 852                             if ( wxSscanf(fileList[i].c_str(),
 853                                           _T("%*s %*s %*s %*s %i %*s %*s %*s %*s"),
 854                                           &filesize) != 9 )
 855                             {
 856                                 // Hmm... Invalid response
 857                                 wxLogTrace(FTP_TRACE_MASK,
 858                                            _T("Invalid LIST response"));
 859                             }
 860                         }
 861                         else // Windows-style response (?)
 862                         {
 863                             if ( wxSscanf(fileList[i].c_str(),
 864                                           _T("%*s %*s %i %*s"),
 865                                           &filesize) != 4 )
 866                             {
 867                                 // something bad happened..?
 868                                 wxLogTrace(FTP_TRACE_MASK,
 869                                            _T("Invalid or unknown LIST response"));
 870                             }
 871                         }
 872                     }
 873                 }
 874             }
 875         }
 876     }
 877
 878     // filesize might still be -1 when exiting
 879     return filesize;
 880 }
 881
 882 #endif // wxUSE_PROTOCOL_FTP
 883