src/common/filename.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/filename.cpp
   3 // Purpose:     wxFileName - encapsulates a file path
   4 // Author:      Robert Roebling, Vadim Zeitlin
   5 // Modified by:
   6 // Created:     28.12.2000
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2000 Robert Roebling
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "filename.h"
  22 #endif
  23
  24 // For compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #ifdef __BORLANDC__
  28   #pragma hdrstop
  29 #endif
  30
  31 #ifndef WX_PRECOMP
  32     #include "wx/intl.h"
  33     #include "wx/log.h"
  34 #endif
  35
  36 #include "wx/filename.h"
  37 #include "wx/tokenzr.h"
  38 #include "wx/config.h"          // for wxExpandEnvVars
  39 #include "wx/utils.h"
  40
  41 #if wxUSE_DYNLIB_CLASS
  42 #include "wx/dynlib.h"
  43 #endif
  44
  45 // For GetShort/LongPathName
  46 #ifdef __WIN32__
  47 #include <windows.h>
  48 #include "wx/msw/winundef.h"
  49 #endif
  50
  51 // at least some of these are required for file mod time
  52 #ifdef __WXGTK__
  53 #include <sys/types.h>
  54 #include <sys/stat.h>
  55 #include <dirent.h>
  56 #include <pwd.h>
  57 #ifndef __VMS
  58 # include <grp.h>
  59 #endif
  60 # include <time.h>
  61 #include <unistd.h>
  62 #endif
  63
  64 // ============================================================================
  65 // implementation
  66 // ============================================================================
  67
  68 // ----------------------------------------------------------------------------
  69 // wxFileName construction
  70 // ----------------------------------------------------------------------------
  71
  72 void wxFileName::Assign( const wxFileName &filepath )
  73 {
  74     m_ext = filepath.GetExt();
  75     m_name = filepath.GetName();
  76     m_dirs = filepath.GetDirs();
  77 }
  78
  79 void wxFileName::Assign( const wxString& path,
  80                          const wxString& name,
  81                          const wxString& ext,
  82                          wxPathFormat format )
  83 {
  84     wxStringTokenizer tn(path, GetPathSeparators(format),
  85                          wxTOKEN_RET_EMPTY_ALL);
  86     bool first = TRUE;
  87     m_dirs.Clear();
  88     while ( tn.HasMoreTokens() )
  89     {
  90         wxString token = tn.GetNextToken();
  91
  92         // If the path starts with a slash, we need the first
  93         // dir entry to be an empty for later reassembly.
  94         if (first || !token.IsEmpty())
  95             m_dirs.Add( token );
  96
  97         first = FALSE;
  98     }
  99
 100     m_ext = ext;
 101     m_name = name;
 102 }
 103
 104 void wxFileName::Assign(const wxString& fullpath,
 105                         wxPathFormat format)
 106 {
 107     wxString path, name, ext;
 108     SplitPath(fullpath, &path, &name, &ext, format);
 109
 110     Assign(path, name, ext, format);
 111 }
 112
 113 void wxFileName::Assign(const wxString& path,
 114                         const wxString& fullname,
 115                         wxPathFormat format)
 116 {
 117     wxString name, ext;
 118     SplitPath(fullname, NULL /* no path */, &name, &ext, format);
 119
 120     Assign(path, name, ext, format);
 121 }
 122
 123 void wxFileName::Clear()
 124 {
 125     m_dirs.Clear();
 126     m_name =
 127     m_ext = wxEmptyString;
 128 }
 129
 130 /* static */
 131 wxFileName wxFileName::FileName(const wxString& file)
 132 {
 133     return wxFileName(file);
 134 }
 135
 136 /* static */
 137 wxFileName wxFileName::DirName(const wxString& dir)
 138 {
 139     wxFileName fn;
 140     fn.AssignDir(dir);
 141     return fn;
 142 }
 143
 144 // ----------------------------------------------------------------------------
 145 // existence tests
 146 // ----------------------------------------------------------------------------
 147
 148 bool wxFileName::FileExists()
 149 {
 150     return wxFileName::FileExists( GetFullPath() );
 151 }
 152
 153 bool wxFileName::FileExists( const wxString &file )
 154 {
 155     return ::wxFileExists( file );
 156 }
 157
 158 bool wxFileName::DirExists()
 159 {
 160     return wxFileName::DirExists( GetFullPath() );
 161 }
 162
 163 bool wxFileName::DirExists( const wxString &dir )
 164 {
 165     return ::wxDirExists( dir );
 166 }
 167
 168 wxDateTime wxFileName::GetModificationTime()
 169 {
 170 #ifdef __WXGTK__
 171     struct stat buff;
 172     stat( GetFullName().fn_str(), &buff );
 173
 174 #if !defined( __EMX__ ) && !defined(__VMS)
 175     struct stat lbuff;
 176     lstat( GetFullName().fn_str(), &lbuff );
 177     struct tm *t = localtime( &lbuff.st_mtime );
 178 #else
 179     struct tm *t = localtime( &buff.st_mtime );
 180 #endif
 181
 182     wxDateTime ret( t->tm_mday, (wxDateTime::Month)t->tm_mon, t->tm_year+1900, t->tm_hour, t->tm_min, t->tm_sec );
 183 #else
 184
 185     wxDateTime ret = wxDateTime::Now();
 186
 187 #endif
 188     return ret;
 189 }
 190
 191 // ----------------------------------------------------------------------------
 192 // CWD and HOME stuff
 193 // ----------------------------------------------------------------------------
 194
 195 void wxFileName::AssignCwd()
 196 {
 197     AssignDir(wxFileName::GetCwd());
 198 }
 199
 200 /* static */
 201 wxString wxFileName::GetCwd()
 202 {
 203     return ::wxGetCwd();
 204 }
 205
 206 bool wxFileName::SetCwd()
 207 {
 208     return wxFileName::SetCwd( GetFullPath() );
 209 }
 210
 211 bool wxFileName::SetCwd( const wxString &cwd )
 212 {
 213     return ::wxSetWorkingDirectory( cwd );
 214 }
 215
 216 void wxFileName::AssignHomeDir()
 217 {
 218     AssignDir(wxFileName::GetHomeDir());
 219 }
 220
 221 wxString wxFileName::GetHomeDir()
 222 {
 223     return ::wxGetHomeDir();
 224 }
 225
 226 void wxFileName::AssignTempFileName( const wxString &prefix )
 227 {
 228     wxString fullname;
 229     if ( wxGetTempFileName(prefix, fullname) )
 230     {
 231         Assign(fullname);
 232     }
 233     else // error
 234     {
 235         Clear();
 236     }
 237 }
 238
 239 // ----------------------------------------------------------------------------
 240 // directory operations
 241 // ----------------------------------------------------------------------------
 242
 243 bool wxFileName::Mkdir( int perm, bool full )
 244 {
 245     return wxFileName::Mkdir( GetFullPath(), perm, full );
 246 }
 247
 248 bool wxFileName::Mkdir( const wxString &dir, int perm, bool full )
 249 {
 250     if (full)
 251     {
 252         wxFileName filename(dir);
 253         wxArrayString dirs = filename.GetDirs();
 254         dirs.Add(filename.GetName());
 255
 256         size_t count = dirs.GetCount();
 257         size_t i;
 258         wxString currPath;
 259         int noErrors = 0;
 260         for ( i = 0; i < count; i++ )
 261         {
 262             currPath += dirs[i];
 263
 264             if (currPath.Last() == wxT(':'))
 265             {
 266                 // Can't create a root directory so continue to next dir
 267                 currPath += wxFILE_SEP_PATH;
 268                 continue;
 269             }
 270
 271             if (!DirExists(currPath))
 272                 if (!wxMkdir(currPath, perm))
 273                     noErrors ++;
 274
 275             if ( (i < (count-1)) )
 276                 currPath += wxFILE_SEP_PATH;
 277         }
 278
 279         return (noErrors == 0);
 280
 281     }
 282     else
 283         return ::wxMkdir( dir, perm );
 284 }
 285
 286 bool wxFileName::Rmdir()
 287 {
 288     return wxFileName::Rmdir( GetFullPath() );
 289 }
 290
 291 bool wxFileName::Rmdir( const wxString &dir )
 292 {
 293     return ::wxRmdir( dir );
 294 }
 295
 296 // ----------------------------------------------------------------------------
 297 // path normalization
 298 // ----------------------------------------------------------------------------
 299
 300 bool wxFileName::Normalize(wxPathNormalize flags,
 301                            const wxString& cwd,
 302                            wxPathFormat format)
 303 {
 304     // the existing path components
 305     wxArrayString dirs = GetDirs();
 306
 307     // the path to prepend in front to make the path absolute
 308     wxFileName curDir;
 309
 310     format = GetFormat(format);
 311
 312     // make the path absolute
 313     if ( (flags & wxPATH_NORM_ABSOLUTE) && !IsAbsolute() )
 314     {
 315         if ( cwd.empty() )
 316             curDir.AssignCwd();
 317         else
 318             curDir.AssignDir(cwd);
 319     }
 320
 321     // handle ~ stuff under Unix only
 322     if ( (format == wxPATH_UNIX) && (flags & wxPATH_NORM_TILDE) )
 323     {
 324         if ( !dirs.IsEmpty() )
 325         {
 326             wxString dir = dirs[0u];
 327             if ( !dir.empty() && dir[0u] == _T('~') )
 328             {
 329                 curDir.AssignDir(wxGetUserHome(dir.c_str() + 1));
 330
 331                 dirs.RemoveAt(0u);
 332             }
 333         }
 334     }
 335
 336     if ( curDir.IsOk() )
 337     {
 338         wxArrayString dirsNew = curDir.GetDirs();
 339         size_t count = dirs.GetCount();
 340         for ( size_t n = 0; n < count; n++ )
 341         {
 342             dirsNew.Add(dirs[n]);
 343         }
 344
 345         dirs = dirsNew;
 346     }
 347
 348     // now deal with ".", ".." and the rest
 349     m_dirs.Empty();
 350     size_t count = dirs.GetCount();
 351     for ( size_t n = 0; n < count; n++ )
 352     {
 353         wxString dir = dirs[n];
 354
 355         if ( flags && wxPATH_NORM_DOTS )
 356         {
 357             if ( dir == wxT(".") )
 358             {
 359                 // just ignore
 360                 continue;
 361             }
 362
 363             if ( dir == wxT("..") )
 364             {
 365                 if ( m_dirs.IsEmpty() )
 366                 {
 367                     wxLogError(_("The path '%s' contains too many \"..\"!"),
 368                                GetFullPath().c_str());
 369                     return FALSE;
 370                 }
 371
 372                 m_dirs.Remove(m_dirs.GetCount() - 1);
 373                 continue;
 374             }
 375         }
 376
 377         if ( flags & wxPATH_NORM_ENV_VARS )
 378         {
 379             dir = wxExpandEnvVars(dir);
 380         }
 381
 382         if ( (flags & wxPATH_NORM_CASE) && !IsCaseSensitive(format) )
 383         {
 384             dir.MakeLower();
 385         }
 386
 387         m_dirs.Add(dir);
 388     }
 389
 390     if ( (flags & wxPATH_NORM_CASE) && !IsCaseSensitive(format) )
 391     {
 392         // VZ: expand env vars here too?
 393
 394         m_name.MakeLower();
 395         m_ext.MakeLower();
 396     }
 397
 398 #if defined(__WXMSW__) && defined(__WIN32__)
 399     if (flags & wxPATH_NORM_LONG)
 400     {
 401         Assign(GetLongPath());
 402     }
 403 #endif
 404
 405     return TRUE;
 406 }
 407
 408 // ----------------------------------------------------------------------------
 409 // filename kind tests
 410 // ----------------------------------------------------------------------------
 411
 412 bool wxFileName::SameAs( const wxFileName &filepath, wxPathFormat format)
 413 {
 414     wxFileName fn1 = *this,
 415                fn2 = filepath;
 416
 417     // get cwd only once - small time saving
 418     wxString cwd = wxGetCwd();
 419     fn1.Normalize(wxPATH_NORM_ALL, cwd, format);
 420     fn2.Normalize(wxPATH_NORM_ALL, cwd, format);
 421
 422     if ( fn1.GetFullPath() == fn2.GetFullPath() )
 423         return TRUE;
 424
 425     // TODO: compare inodes for Unix, this works even when filenames are
 426     //       different but files are the same (symlinks) (VZ)
 427
 428     return FALSE;
 429 }
 430
 431 /* static */
 432 bool wxFileName::IsCaseSensitive( wxPathFormat format )
 433 {
 434     // only DOS filenames are case-sensitive
 435     return GetFormat(format) != wxPATH_DOS;
 436 }
 437
 438 bool wxFileName::IsRelative( wxPathFormat format )
 439 {
 440     return !IsAbsolute(format);
 441 }
 442
 443 bool wxFileName::IsAbsolute( wxPathFormat format )
 444 {
 445     wxChar ch = m_dirs.IsEmpty() ? _T('\0') : m_dirs[0u][0u];
 446
 447     // Hack to cope with e.g. c:\thing - need something better
 448     wxChar driveSep = _T('\0');
 449     if (!m_dirs.IsEmpty() && m_dirs[0].Length() > 1)
 450         driveSep = m_dirs[0u][1u];
 451
 452     // the path is absolute if it starts with a path separator or, only for
 453     // Unix filenames, with "~" or "~user"
 454     return IsPathSeparator(ch, format) ||
 455            driveSep == _T(':') ||
 456            (GetFormat(format) == wxPATH_UNIX && ch == _T('~') );
 457 }
 458
 459 /* static */
 460 wxString wxFileName::GetPathSeparators(wxPathFormat format)
 461 {
 462     wxString seps;
 463     switch ( GetFormat(format) )
 464     {
 465         case wxPATH_DOS:
 466             // accept both as native APIs do
 467             seps << wxFILE_SEP_PATH_UNIX << wxFILE_SEP_PATH_DOS;
 468             break;
 469
 470         default:
 471             wxFAIL_MSG( _T("unknown wxPATH_XXX style") );
 472             // fall through
 473
 474         case wxPATH_UNIX:
 475             seps = wxFILE_SEP_PATH_UNIX;
 476             break;
 477
 478         case wxPATH_MAC:
 479             seps = wxFILE_SEP_PATH_MAC;
 480             break;
 481     }
 482
 483     return seps;
 484 }
 485
 486 /* static */
 487 bool wxFileName::IsPathSeparator(wxChar ch, wxPathFormat format)
 488 {
 489     return GetPathSeparators(format).Find(ch) != wxNOT_FOUND;
 490 }
 491
 492 bool wxFileName::IsWild( wxPathFormat format )
 493 {
 494     // FIXME: this is probably false for Mac and this is surely wrong for most
 495     //        of Unix shells (think about "[...]")
 496     return m_name.find_first_of(_T("*?")) != wxString::npos;
 497 }
 498
 499 // ----------------------------------------------------------------------------
 500 // path components manipulation
 501 // ----------------------------------------------------------------------------
 502
 503 void wxFileName::AppendDir( const wxString &dir )
 504 {
 505     m_dirs.Add( dir );
 506 }
 507
 508 void wxFileName::PrependDir( const wxString &dir )
 509 {
 510     m_dirs.Insert( dir, 0 );
 511 }
 512
 513 void wxFileName::InsertDir( int before, const wxString &dir )
 514 {
 515     m_dirs.Insert( dir, before );
 516 }
 517
 518 void wxFileName::RemoveDir( int pos )
 519 {
 520     m_dirs.Remove( (size_t)pos );
 521 }
 522
 523 // ----------------------------------------------------------------------------
 524 // accessors
 525 // ----------------------------------------------------------------------------
 526
 527 void wxFileName::SetFullName(const wxString& fullname)
 528 {
 529     SplitPath(fullname, NULL /* no path */, &m_name, &m_ext);
 530 }
 531
 532 wxString wxFileName::GetFullName() const
 533 {
 534     wxString fullname = m_name;
 535     if ( !m_ext.empty() )
 536     {
 537         fullname << wxFILE_SEP_EXT << m_ext;
 538     }
 539
 540     return fullname;
 541 }
 542
 543 wxString wxFileName::GetPath( bool add_separator, wxPathFormat format ) const
 544 {
 545     format = GetFormat( format );
 546
 547     wxString ret;
 548     size_t count = m_dirs.GetCount();
 549     for ( size_t i = 0; i < count; i++ )
 550     {
 551         ret += m_dirs[i];
 552         if ( add_separator || (i < count) )
 553             ret += wxFILE_SEP_PATH;
 554     }
 555
 556     return ret;
 557 }
 558
 559 wxString wxFileName::GetFullPath( wxPathFormat format ) const
 560 {
 561     return GetPathWithSep() + GetFullName();
 562 }
 563
 564 // Return the short form of the path (returns identity on non-Windows platforms)
 565 wxString wxFileName::GetShortPath() const
 566 {
 567 #if defined(__WXMSW__) && defined(__WIN32__)
 568     wxString path(GetFullPath());
 569     wxString pathOut;
 570     DWORD sz = ::GetShortPathName(path, NULL, 0);
 571     bool ok = sz != 0;
 572     if ( ok )
 573     {
 574         ok = ::GetShortPathName
 575                (
 576                 path,
 577                 pathOut.GetWriteBuf(sz),
 578                 sz
 579                ) != 0;
 580         pathOut.UngetWriteBuf();
 581     }
 582     if (ok)
 583         return pathOut;
 584     else
 585         return path;
 586 #else
 587     return GetFullPath();
 588 #endif
 589 }
 590
 591 // Return the long form of the path (returns identity on non-Windows platforms)
 592 wxString wxFileName::GetLongPath() const
 593 {
 594 #if defined(__WXMSW__) && defined(__WIN32__)
 595     wxString path(GetFullPath());
 596     wxString pathOut;
 597     bool success = FALSE;
 598
 599 #if wxUSE_DYNLIB_CLASS
 600     typedef DWORD (*GET_LONG_PATH_NAME)(const wxChar *, wxChar *, DWORD);
 601
 602     static bool s_triedToLoad = FALSE;
 603     static GET_LONG_PATH_NAME s_pfnGetLongPathName = NULL;
 604
 605     if ( !s_triedToLoad )
 606     {
 607         s_triedToLoad = TRUE;
 608
 609         wxDllType dllKernel = wxDllLoader::LoadLibrary(_T("kernel32"));
 610         if ( 0 ) // dllKernel )
 611         {
 612             // may succeed or fail depending on the Windows version
 613 #ifdef _UNICODE
 614             s_pfnGetLongPathName = (GET_LONG_PATH_NAME) wxDllLoader::GetSymbol(dllKernel, _T("GetLongPathNameW"));
 615 #else
 616             s_pfnGetLongPathName = (GET_LONG_PATH_NAME) wxDllLoader::GetSymbol(dllKernel, _T("GetLongPathNameA"));
 617 #endif
 618
 619             wxDllLoader::UnloadLibrary(dllKernel);
 620
 621             if ( s_pfnGetLongPathName )
 622             {
 623                 DWORD dwSize = (*s_pfnGetLongPathName)(path, NULL, 0);
 624                 bool ok = dwSize > 0;
 625
 626                 if ( ok )
 627                 {
 628                     DWORD sz = (*s_pfnGetLongPathName)(path, NULL, 0);
 629                     ok = sz != 0;
 630                     if ( ok )
 631                     {
 632                         ok = (*s_pfnGetLongPathName)
 633                                 (
 634                                 path,
 635                                 pathOut.GetWriteBuf(sz),
 636                                 sz
 637                                 ) != 0;
 638                         pathOut.UngetWriteBuf();
 639
 640                         success = TRUE;
 641                     }
 642                 }
 643             }
 644         }
 645     }
 646     if (success)
 647         return pathOut;
 648 #endif
 649     // wxUSE_DYNLIB_CLASS
 650
 651     if (!success)
 652     {
 653         // The OS didn't support GetLongPathName, or some other error.
 654         // We need to call FindFirstFile on each component in turn.
 655
 656         WIN32_FIND_DATA findFileData;
 657         HANDLE hFind;
 658         pathOut = wxEmptyString;
 659
 660         wxArrayString dirs = GetDirs();
 661         dirs.Add(GetName());
 662
 663         size_t count = dirs.GetCount();
 664         size_t i;
 665         wxString tmpPath;
 666
 667         for ( i = 0; i < count; i++ )
 668         {
 669             // We're using pathOut to collect the long-name path,
 670             // but using a temporary for appending the last path component which may be short-name
 671             tmpPath = pathOut + dirs[i];
 672
 673             if (tmpPath.Last() == wxT(':'))
 674             {
 675                 // Can't pass a drive and root dir to FindFirstFile,
 676                 // so continue to next dir
 677                 tmpPath += wxFILE_SEP_PATH;
 678                 pathOut = tmpPath;
 679                 continue;
 680             }
 681
 682             hFind = ::FindFirstFile(tmpPath, &findFileData);
 683             if (hFind == INVALID_HANDLE_VALUE)
 684             {
 685                 // Error: return immediately with the original path
 686                 return path;
 687             }
 688             else
 689             {
 690                 pathOut += findFileData.cFileName;
 691                 if ( (i < (count-1)) )
 692                     pathOut += wxFILE_SEP_PATH;
 693
 694                 ::FindClose(hFind);
 695             }
 696         }
 697     }
 698     return pathOut;
 699 #else
 700     return GetFullPath();
 701 #endif
 702 }
 703
 704 wxPathFormat wxFileName::GetFormat( wxPathFormat format )
 705 {
 706     if (format == wxPATH_NATIVE)
 707     {
 708 #if defined(__WXMSW__) || defined(__WXPM__)
 709         format = wxPATH_DOS;
 710 #elif defined(__WXMAC__)
 711         format = wxPATH_UNIX; // that's the way the rest of wx' code works right now
 712 #else
 713         format = wxPATH_UNIX;
 714 #endif
 715     }
 716     return format;
 717 }
 718
 719 // ----------------------------------------------------------------------------
 720 // path splitting function
 721 // ----------------------------------------------------------------------------
 722
 723 void wxFileName::SplitPath(const wxString& fullpath,
 724                            wxString *pstrPath,
 725                            wxString *pstrName,
 726                            wxString *pstrExt,
 727                            wxPathFormat format)
 728 {
 729     format = GetFormat(format);
 730
 731     // find the positions of the last dot and last path separator in the path
 732     size_t posLastDot = fullpath.find_last_of(wxFILE_SEP_EXT);
 733     size_t posLastSlash = fullpath.find_last_of(GetPathSeparators(format));
 734
 735     if ( (posLastDot != wxString::npos) && (format == wxPATH_UNIX) )
 736     {
 737         if ( (posLastDot == 0) ||
 738              (fullpath[posLastDot - 1] == wxFILE_SEP_PATH_UNIX) )
 739         {
 740             // under Unix, dot may be (and commonly is) the first character of
 741             // the filename, don't treat the entire filename as extension in
 742             // this case
 743             posLastDot = wxString::npos;
 744         }
 745     }
 746
 747     // if we do have a dot and a slash, check that the dot is in the name part
 748     if ( (posLastDot != wxString::npos) &&
 749          (posLastSlash != wxString::npos) &&
 750          (posLastDot < posLastSlash) )
 751     {
 752         // the dot is part of the path, not the start of the extension
 753         posLastDot = wxString::npos;
 754     }
 755
 756     // now fill in the variables provided by user
 757     if ( pstrPath )
 758     {
 759         if ( posLastSlash == wxString::npos )
 760         {
 761             // no path at all
 762             pstrPath->Empty();
 763         }
 764         else
 765         {
 766             // take all until the separator
 767             *pstrPath = fullpath.Left(posLastSlash);
 768         }
 769     }
 770
 771     if ( pstrName )
 772     {
 773         // take all characters starting from the one after the last slash and
 774         // up to, but excluding, the last dot
 775         size_t nStart = posLastSlash == wxString::npos ? 0 : posLastSlash + 1;
 776         size_t count;
 777         if ( posLastDot == wxString::npos )
 778         {
 779             // take all until the end
 780             count = wxString::npos;
 781         }
 782         else if ( posLastSlash == wxString::npos )
 783         {
 784             count = posLastDot;
 785         }
 786         else // have both dot and slash
 787         {
 788             count = posLastDot - posLastSlash - 1;
 789         }
 790
 791         *pstrName = fullpath.Mid(nStart, count);
 792     }
 793
 794     if ( pstrExt )
 795     {
 796         if ( posLastDot == wxString::npos )
 797         {
 798             // no extension
 799             pstrExt->Empty();
 800         }
 801         else
 802         {
 803             // take everything after the dot
 804             *pstrExt = fullpath.Mid(posLastDot + 1);
 805         }
 806     }
 807 }