src/common/appbase.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        common/base/appbase.cpp
   3 // Purpose:     implements wxAppConsole class
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     19.06.2003 (extracted from common/appcmn.cpp)
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2003 Vadim Zeitlin <vadim@wxwindows.org>
   9 // License:     wxWindows license
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 // for compilers that support precompilation, includes "wx.h".
  21 #include "wx/wxprec.h"
  22
  23 #ifdef __BORLANDC__
  24     #pragma hdrstop
  25 #endif
  26
  27 #ifndef WX_PRECOMP
  28     #include "wx/app.h"
  29     #include "wx/intl.h"
  30     #include "wx/list.h"
  31     #include "wx/log.h"
  32 #endif //WX_PRECOMP
  33
  34 #include "wx/utils.h"
  35 #include "wx/apptrait.h"
  36 #include "wx/cmdline.h"
  37 #include "wx/confbase.h"
  38 #include "wx/filename.h"
  39 #include "wx/msgout.h"
  40 #include "wx/tokenzr.h"
  41
  42 #if !defined(__WXMSW__) || defined(__WXMICROWIN__)
  43   #include  <signal.h>      // for SIGTRAP used by wxTrap()
  44 #endif  //Win/Unix
  45
  46 #if defined(__WXMSW__)
  47   #include  "wx/msw/wrapwin.h"  // includes windows.h for MessageBox()
  48 #endif
  49
  50 #if wxUSE_FONTMAP
  51     #include "wx/fontmap.h"
  52 #endif // wxUSE_FONTMAP
  53
  54 #if defined(__DARWIN__) && defined(_MSL_USING_MW_C_HEADERS) && _MSL_USING_MW_C_HEADERS
  55     // For MacTypes.h for Debugger function
  56     #include <CoreFoundation/CFBase.h>
  57 #endif
  58
  59 #if defined(__WXMAC__)
  60     #ifdef __DARWIN__
  61         #include  <CoreServices/CoreServices.h>
  62     #else
  63         #include  "wx/mac/private.h"  // includes mac headers
  64     #endif
  65 #endif // __WXMAC__
  66
  67 #ifdef __WXDEBUG__
  68     #if wxUSE_STACKWALKER
  69         #include "wx/stackwalk.h"
  70         #ifdef __WXMSW__
  71             #include "wx/msw/debughlp.h"
  72         #endif
  73     #endif // wxUSE_STACKWALKER
  74 #endif // __WXDEBUG__
  75
  76 // wxABI_VERSION can be defined when compiling applications but it should be
  77 // left undefined when compiling the library itself, it is then set to its
  78 // default value in version.h
  79 #if wxABI_VERSION != wxMAJOR_VERSION * 10000 + wxMINOR_VERSION * 100 + 99
  80 #error "wxABI_VERSION should not be defined when compiling the library"
  81 #endif
  82
  83 // ----------------------------------------------------------------------------
  84 // private functions prototypes
  85 // ----------------------------------------------------------------------------
  86
  87 #ifdef __WXDEBUG__
  88     // really just show the assert dialog
  89     static bool DoShowAssertDialog(const wxString& msg);
  90
  91     // prepare for showing the assert dialog, use the given traits or
  92     // DoShowAssertDialog() as last fallback to really show it
  93     static
  94     void ShowAssertDialog(const wxChar *szFile,
  95                           int nLine,
  96                           const wxChar *szCond,
  97                           const wxChar *szMsg,
  98                           wxAppTraits *traits = NULL);
  99
 100     // turn on the trace masks specified in the env variable WXTRACE
 101     static void LINKAGEMODE SetTraceMasks();
 102 #endif // __WXDEBUG__
 103
 104 // ----------------------------------------------------------------------------
 105 // global vars
 106 // ----------------------------------------------------------------------------
 107
 108 wxAppConsole *wxAppConsole::ms_appInstance = NULL;
 109
 110 wxAppInitializerFunction wxAppConsole::ms_appInitFn = NULL;
 111
 112 // ============================================================================
 113 // wxAppConsole implementation
 114 // ============================================================================
 115
 116 // ----------------------------------------------------------------------------
 117 // ctor/dtor
 118 // ----------------------------------------------------------------------------
 119
 120 wxAppConsole::wxAppConsole()
 121 {
 122     m_traits = NULL;
 123
 124     ms_appInstance = this;
 125
 126 #ifdef __WXDEBUG__
 127     SetTraceMasks();
 128 #if wxUSE_UNICODE
 129     // In unicode mode the SetTraceMasks call can cause an apptraits to be
 130     // created, but since we are still in the constructor the wrong kind will
 131     // be created for GUI apps.  Destroy it so it can be created again later.
 132     delete m_traits;
 133     m_traits = NULL;
 134 #endif
 135 #endif
 136 }
 137
 138 wxAppConsole::~wxAppConsole()
 139 {
 140     delete m_traits;
 141 }
 142
 143 // ----------------------------------------------------------------------------
 144 // initilization/cleanup
 145 // ----------------------------------------------------------------------------
 146
 147 bool wxAppConsole::Initialize(int& argcOrig, wxChar **argvOrig)
 148 {
 149     // remember the command line arguments
 150     argc = argcOrig;
 151     argv = argvOrig;
 152
 153 #ifndef __WXPALMOS__
 154     if ( m_appName.empty() && argv )
 155     {
 156         // the application name is, by default, the name of its executable file
 157         wxFileName::SplitPath(argv[0], NULL, &m_appName, NULL);
 158     }
 159 #endif
 160
 161     return true;
 162 }
 163
 164 void wxAppConsole::CleanUp()
 165 {
 166 }
 167
 168 // ----------------------------------------------------------------------------
 169 // OnXXX() callbacks
 170 // ----------------------------------------------------------------------------
 171
 172 bool wxAppConsole::OnInit()
 173 {
 174 #if wxUSE_CMDLINE_PARSER
 175     wxCmdLineParser parser(argc, argv);
 176
 177     OnInitCmdLine(parser);
 178
 179     bool cont;
 180     switch ( parser.Parse(false /* don't show usage */) )
 181     {
 182         case -1:
 183             cont = OnCmdLineHelp(parser);
 184             break;
 185
 186         case 0:
 187             cont = OnCmdLineParsed(parser);
 188             break;
 189
 190         default:
 191             cont = OnCmdLineError(parser);
 192             break;
 193     }
 194
 195     if ( !cont )
 196         return false;
 197 #endif // wxUSE_CMDLINE_PARSER
 198
 199     return true;
 200 }
 201
 202 int wxAppConsole::OnExit()
 203 {
 204 #if wxUSE_CONFIG
 205     // delete the config object if any (don't use Get() here, but Set()
 206     // because Get() could create a new config object)
 207     delete wxConfigBase::Set((wxConfigBase *) NULL);
 208 #endif // wxUSE_CONFIG
 209
 210     // use Set(NULL) and not Get() to avoid creating a message output object on
 211     // demand when we just want to delete it
 212     delete wxMessageOutput::Set(NULL);
 213
 214     return 0;
 215 }
 216
 217 void wxAppConsole::Exit()
 218 {
 219     exit(-1);
 220 }
 221
 222 // ----------------------------------------------------------------------------
 223 // traits stuff
 224 // ----------------------------------------------------------------------------
 225
 226 wxAppTraits *wxAppConsole::CreateTraits()
 227 {
 228     return new wxConsoleAppTraits;
 229 }
 230
 231 wxAppTraits *wxAppConsole::GetTraits()
 232 {
 233     // FIXME-MT: protect this with a CS?
 234     if ( !m_traits )
 235     {
 236         m_traits = CreateTraits();
 237
 238         wxASSERT_MSG( m_traits, _T("wxApp::CreateTraits() failed?") );
 239     }
 240
 241     return m_traits;
 242 }
 243
 244 // we must implement CreateXXX() in wxApp itself for backwards compatibility
 245 #if WXWIN_COMPATIBILITY_2_4
 246
 247 #if wxUSE_LOG
 248
 249 wxLog *wxAppConsole::CreateLogTarget()
 250 {
 251     wxAppTraits *traits = GetTraits();
 252     return traits ? traits->CreateLogTarget() : NULL;
 253 }
 254
 255 #endif // wxUSE_LOG
 256
 257 wxMessageOutput *wxAppConsole::CreateMessageOutput()
 258 {
 259     wxAppTraits *traits = GetTraits();
 260     return traits ? traits->CreateMessageOutput() : NULL;
 261 }
 262
 263 #endif // WXWIN_COMPATIBILITY_2_4
 264
 265 // ----------------------------------------------------------------------------
 266 // event processing
 267 // ----------------------------------------------------------------------------
 268
 269 void wxAppConsole::ProcessPendingEvents()
 270 {
 271 #if wxUSE_THREADS
 272     if ( !wxPendingEventsLocker )
 273         return;
 274 #endif
 275
 276     // ensure that we're the only thread to modify the pending events list
 277     wxENTER_CRIT_SECT( *wxPendingEventsLocker );
 278
 279     if ( !wxPendingEvents )
 280     {
 281         wxLEAVE_CRIT_SECT( *wxPendingEventsLocker );
 282         return;
 283     }
 284
 285     // iterate until the list becomes empty
 286     wxList::compatibility_iterator node = wxPendingEvents->GetFirst();
 287     while (node)
 288     {
 289         wxEvtHandler *handler = (wxEvtHandler *)node->GetData();
 290         wxPendingEvents->Erase(node);
 291
 292         // In ProcessPendingEvents(), new handlers might be add
 293         // and we can safely leave the critical section here.
 294         wxLEAVE_CRIT_SECT( *wxPendingEventsLocker );
 295
 296         handler->ProcessPendingEvents();
 297
 298         wxENTER_CRIT_SECT( *wxPendingEventsLocker );
 299
 300         node = wxPendingEvents->GetFirst();
 301     }
 302
 303     wxLEAVE_CRIT_SECT( *wxPendingEventsLocker );
 304 }
 305
 306 int wxAppConsole::FilterEvent(wxEvent& WXUNUSED(event))
 307 {
 308     // process the events normally by default
 309     return -1;
 310 }
 311
 312 // ----------------------------------------------------------------------------
 313 // exception handling
 314 // ----------------------------------------------------------------------------
 315
 316 #if wxUSE_EXCEPTIONS
 317
 318 void
 319 wxAppConsole::HandleEvent(wxEvtHandler *handler,
 320                           wxEventFunction func,
 321                           wxEvent& event) const
 322 {
 323     // by default, simply call the handler
 324     (handler->*func)(event);
 325 }
 326
 327 bool
 328 wxAppConsole::OnExceptionInMainLoop()
 329 {
 330     throw;
 331
 332     // some compilers are too stupid to know that we never return after throw
 333 #if defined(__DMC__) || (defined(_MSC_VER) && _MSC_VER < 1200)
 334     return false;
 335 #endif
 336 }
 337
 338 #endif // wxUSE_EXCEPTIONS
 339
 340 // ----------------------------------------------------------------------------
 341 // cmd line parsing
 342 // ----------------------------------------------------------------------------
 343
 344 #if wxUSE_CMDLINE_PARSER
 345
 346 #define OPTION_VERBOSE _T("verbose")
 347
 348 void wxAppConsole::OnInitCmdLine(wxCmdLineParser& parser)
 349 {
 350     // the standard command line options
 351     static const wxCmdLineEntryDesc cmdLineDesc[] =
 352     {
 353         {
 354             wxCMD_LINE_SWITCH,
 355             _T("h"),
 356             _T("help"),
 357             gettext_noop("show this help message"),
 358             wxCMD_LINE_VAL_NONE,
 359             wxCMD_LINE_OPTION_HELP
 360         },
 361
 362 #if wxUSE_LOG
 363         {
 364             wxCMD_LINE_SWITCH,
 365             wxEmptyString,
 366             OPTION_VERBOSE,
 367             gettext_noop("generate verbose log messages"),
 368             wxCMD_LINE_VAL_NONE,
 369             0x0
 370         },
 371 #endif // wxUSE_LOG
 372
 373         // terminator
 374         {
 375             wxCMD_LINE_NONE,
 376             wxEmptyString,
 377             wxEmptyString,
 378             wxEmptyString,
 379             wxCMD_LINE_VAL_NONE,
 380             0x0
 381         }
 382     };
 383
 384     parser.SetDesc(cmdLineDesc);
 385 }
 386
 387 bool wxAppConsole::OnCmdLineParsed(wxCmdLineParser& parser)
 388 {
 389 #if wxUSE_LOG
 390     if ( parser.Found(OPTION_VERBOSE) )
 391     {
 392         wxLog::SetVerbose(true);
 393     }
 394 #else
 395     wxUnusedVar(parser);
 396 #endif // wxUSE_LOG
 397
 398     return true;
 399 }
 400
 401 bool wxAppConsole::OnCmdLineHelp(wxCmdLineParser& parser)
 402 {
 403     parser.Usage();
 404
 405     return false;
 406 }
 407
 408 bool wxAppConsole::OnCmdLineError(wxCmdLineParser& parser)
 409 {
 410     parser.Usage();
 411
 412     return false;
 413 }
 414
 415 #endif // wxUSE_CMDLINE_PARSER
 416
 417 // ----------------------------------------------------------------------------
 418 // debugging support
 419 // ----------------------------------------------------------------------------
 420
 421 /* static */
 422 bool wxAppConsole::CheckBuildOptions(const char *optionsSignature,
 423                                      const char *componentName)
 424 {
 425 #if 0 // can't use wxLogTrace, not up and running yet
 426     printf("checking build options object '%s' (ptr %p) in '%s'\n",
 427              optionsSignature, optionsSignature, componentName);
 428 #endif
 429
 430     if ( strcmp(optionsSignature, WX_BUILD_OPTIONS_SIGNATURE) != 0 )
 431     {
 432         wxString lib = wxString::FromAscii(WX_BUILD_OPTIONS_SIGNATURE);
 433         wxString prog = wxString::FromAscii(optionsSignature);
 434         wxString progName = wxString::FromAscii(componentName);
 435         wxString msg;
 436
 437         msg.Printf(_T("Mismatch between the program and library build versions detected.\nThe library used %s,\nand %s used %s."),
 438                    lib.c_str(), progName.c_str(), prog.c_str());
 439
 440         wxLogFatalError(msg.c_str());
 441
 442         // normally wxLogFatalError doesn't return
 443         return false;
 444     }
 445 #undef wxCMP
 446
 447     return true;
 448 }
 449
 450 #ifdef __WXDEBUG__
 451
 452 void wxAppConsole::OnAssert(const wxChar *file,
 453                             int line,
 454                             const wxChar *cond,
 455                             const wxChar *msg)
 456 {
 457     ShowAssertDialog(file, line, cond, msg, GetTraits());
 458 }
 459
 460 #endif // __WXDEBUG__
 461
 462 #if WXWIN_COMPATIBILITY_2_4
 463
 464 bool wxAppConsole::CheckBuildOptions(const wxBuildOptions& buildOptions)
 465 {
 466     return CheckBuildOptions(buildOptions.m_signature, "your program");
 467 }
 468
 469 #endif
 470
 471 // ============================================================================
 472 // other classes implementations
 473 // ============================================================================
 474
 475 // ----------------------------------------------------------------------------
 476 // wxConsoleAppTraitsBase
 477 // ----------------------------------------------------------------------------
 478
 479 #if wxUSE_LOG
 480
 481 wxLog *wxConsoleAppTraitsBase::CreateLogTarget()
 482 {
 483     return new wxLogStderr;
 484 }
 485
 486 #endif // wxUSE_LOG
 487
 488 wxMessageOutput *wxConsoleAppTraitsBase::CreateMessageOutput()
 489 {
 490     return new wxMessageOutputStderr;
 491 }
 492
 493 #if wxUSE_FONTMAP
 494
 495 wxFontMapper *wxConsoleAppTraitsBase::CreateFontMapper()
 496 {
 497     return (wxFontMapper *)new wxFontMapperBase;
 498 }
 499
 500 #endif // wxUSE_FONTMAP
 501
 502 wxRendererNative *wxConsoleAppTraitsBase::CreateRenderer()
 503 {
 504     // console applications don't use renderers
 505     return NULL;
 506 }
 507
 508 #ifdef __WXDEBUG__
 509 bool wxConsoleAppTraitsBase::ShowAssertDialog(const wxString& msg)
 510 {
 511     return wxAppTraitsBase::ShowAssertDialog(msg);
 512 }
 513 #endif
 514
 515 bool wxConsoleAppTraitsBase::HasStderr()
 516 {
 517     // console applications always have stderr, even under Mac/Windows
 518     return true;
 519 }
 520
 521 void wxConsoleAppTraitsBase::ScheduleForDestroy(wxObject *object)
 522 {
 523     delete object;
 524 }
 525
 526 void wxConsoleAppTraitsBase::RemoveFromPendingDelete(wxObject * WXUNUSED(object))
 527 {
 528     // nothing to do
 529 }
 530
 531 #if wxUSE_SOCKETS
 532 GSocketGUIFunctionsTable* wxConsoleAppTraitsBase::GetSocketGUIFunctionsTable()
 533 {
 534     return NULL;
 535 }
 536 #endif
 537
 538 // ----------------------------------------------------------------------------
 539 // wxAppTraits
 540 // ----------------------------------------------------------------------------
 541
 542 #ifdef __WXDEBUG__
 543
 544 bool wxAppTraitsBase::ShowAssertDialog(const wxString& msg)
 545 {
 546     return DoShowAssertDialog(msg);
 547 }
 548
 549 #endif // __WXDEBUG__
 550
 551 // ============================================================================
 552 // global functions implementation
 553 // ============================================================================
 554
 555 void wxExit()
 556 {
 557     if ( wxTheApp )
 558     {
 559         wxTheApp->Exit();
 560     }
 561     else
 562     {
 563         // what else can we do?
 564         exit(-1);
 565     }
 566 }
 567
 568 void wxWakeUpIdle()
 569 {
 570     if ( wxTheApp )
 571     {
 572         wxTheApp->WakeUpIdle();
 573     }
 574     //else: do nothing, what can we do?
 575 }
 576
 577 #ifdef  __WXDEBUG__
 578
 579 // wxASSERT() helper
 580 bool wxAssertIsEqual(int x, int y)
 581 {
 582     return x == y;
 583 }
 584
 585 // break into the debugger
 586 void wxTrap()
 587 {
 588 #if defined(__WXMSW__) && !defined(__WXMICROWIN__)
 589     DebugBreak();
 590 #elif defined(__WXMAC__) && !defined(__DARWIN__)
 591     #if __powerc
 592         Debugger();
 593     #else
 594         SysBreak();
 595     #endif
 596 #elif defined(_MSL_USING_MW_C_HEADERS) && _MSL_USING_MW_C_HEADERS
 597     Debugger();
 598 #elif defined(__UNIX__)
 599     raise(SIGTRAP);
 600 #else
 601     // TODO
 602 #endif // Win/Unix
 603 }
 604
 605 void wxAssert(int cond,
 606               const wxChar *szFile,
 607               int nLine,
 608               const wxChar *szCond,
 609               const wxChar *szMsg)
 610 {
 611     if ( !cond )
 612         wxOnAssert(szFile, nLine, szCond, szMsg);
 613 }
 614
 615 // this function is called when an assert fails
 616 void wxOnAssert(const wxChar *szFile,
 617                 int nLine,
 618                 const wxChar *szCond,
 619                 const wxChar *szMsg)
 620 {
 621     // FIXME MT-unsafe
 622     static bool s_bInAssert = false;
 623
 624     if ( s_bInAssert )
 625     {
 626         // He-e-e-e-elp!! we're trapped in endless loop
 627         wxTrap();
 628
 629         s_bInAssert = false;
 630
 631         return;
 632     }
 633
 634     s_bInAssert = true;
 635
 636     if ( !wxTheApp )
 637     {
 638         // by default, show the assert dialog box -- we can't customize this
 639         // behaviour
 640         ShowAssertDialog(szFile, nLine, szCond, szMsg);
 641     }
 642     else
 643     {
 644         // let the app process it as it wants
 645         wxTheApp->OnAssert(szFile, nLine, szCond, szMsg);
 646     }
 647
 648     s_bInAssert = false;
 649 }
 650
 651 #endif // __WXDEBUG__
 652
 653 // ============================================================================
 654 // private functions implementation
 655 // ============================================================================
 656
 657 #ifdef __WXDEBUG__
 658
 659 static void LINKAGEMODE SetTraceMasks()
 660 {
 661 #if wxUSE_LOG
 662     wxString mask;
 663     if ( wxGetEnv(wxT("WXTRACE"), &mask) )
 664     {
 665         wxStringTokenizer tkn(mask, wxT(",;:"));
 666         while ( tkn.HasMoreTokens() )
 667             wxLog::AddTraceMask(tkn.GetNextToken());
 668     }
 669 #endif // wxUSE_LOG
 670 }
 671
 672 bool DoShowAssertDialog(const wxString& msg)
 673 {
 674     // under MSW we can show the dialog even in the console mode
 675 #if defined(__WXMSW__) && !defined(__WXMICROWIN__)
 676     wxString msgDlg(msg);
 677
 678     // this message is intentionally not translated -- it is for
 679     // developpers only
 680     msgDlg += wxT("\nDo you want to stop the program?\n")
 681               wxT("You can also choose [Cancel] to suppress ")
 682               wxT("further warnings.");
 683
 684     switch ( ::MessageBox(NULL, msgDlg, _T("wxWidgets Debug Alert"),
 685                           MB_YESNOCANCEL | MB_ICONSTOP ) )
 686     {
 687         case IDYES:
 688             wxTrap();
 689             break;
 690
 691         case IDCANCEL:
 692             // stop the asserts
 693             return true;
 694
 695         //case IDNO: nothing to do
 696     }
 697 #else // !__WXMSW__
 698     wxFprintf(stderr, wxT("%s\n"), msg.c_str());
 699     fflush(stderr);
 700
 701     // TODO: ask the user to enter "Y" or "N" on the console?
 702     wxTrap();
 703 #endif // __WXMSW__/!__WXMSW__
 704
 705     // continue with the asserts
 706     return false;
 707 }
 708
 709 #if wxUSE_STACKWALKER
 710 static wxString GetAssertStackTrace()
 711 {
 712     wxString stackTrace;
 713
 714     class StackDump : public wxStackWalker
 715     {
 716     public:
 717         StackDump() { }
 718
 719         const wxString& GetStackTrace() const { return m_stackTrace; }
 720
 721     protected:
 722         virtual void OnStackFrame(const wxStackFrame& frame)
 723         {
 724             m_stackTrace << wxString::Format
 725                             (
 726                               _T("[%02d] "),
 727                               wx_truncate_cast(int, frame.GetLevel())
 728                             );
 729
 730             wxString name = frame.GetName();
 731             if ( !name.empty() )
 732             {
 733                 m_stackTrace << wxString::Format(_T("%-40s"), name.c_str());
 734             }
 735             else
 736             {
 737                 m_stackTrace << wxString::Format(_T("0x%08p"),
 738                                                  frame.GetAddress());
 739             }
 740
 741             if ( frame.HasSourceLocation() )
 742             {
 743                 m_stackTrace << _T('\t')
 744                              << frame.GetFileName()
 745                              << _T(':')
 746                              << frame.GetLine();
 747             }
 748
 749             m_stackTrace << _T('\n');
 750         }
 751
 752     private:
 753         wxString m_stackTrace;
 754     };
 755
 756     StackDump dump;
 757     dump.Walk(5); // don't show OnAssert() call itself
 758     stackTrace = dump.GetStackTrace();
 759
 760     // don't show more than maxLines or we could get a dialog too tall to be
 761     // shown on screen: 20 should be ok everywhere as even with 15 pixel high
 762     // characters it is still only 300 pixels...
 763     static const int maxLines = 20;
 764     const int count = stackTrace.Freq(wxT('\n'));
 765     for ( int i = 0; i < count - maxLines; i++ )
 766         stackTrace = stackTrace.BeforeLast(wxT('\n'));
 767
 768     return stackTrace;
 769 }
 770 #endif // wxUSE_STACKWALKER
 771
 772 // show the assert modal dialog
 773 static
 774 void ShowAssertDialog(const wxChar *szFile,
 775                       int nLine,
 776                       const wxChar *szCond,
 777                       const wxChar *szMsg,
 778                       wxAppTraits *traits)
 779 {
 780     // this variable can be set to true to suppress "assert failure" messages
 781     static bool s_bNoAsserts = false;
 782
 783     wxString msg;
 784     msg.reserve(2048);
 785
 786     // make life easier for people using VC++ IDE by using this format: like
 787     // this, clicking on the message will take us immediately to the place of
 788     // the failed assert
 789     msg.Printf(wxT("%s(%d): assert \"%s\" failed"), szFile, nLine, szCond);
 790
 791     if ( szMsg )
 792     {
 793         msg << _T(": ") << szMsg;
 794     }
 795     else // no message given
 796     {
 797         msg << _T('.');
 798     }
 799
 800 #if wxUSE_STACKWALKER
 801     const wxString stackTrace = GetAssertStackTrace();
 802     if ( !stackTrace.empty() )
 803     {
 804         msg << _T("\n\nCall stack:\n") << stackTrace;
 805     }
 806 #endif // wxUSE_STACKWALKER
 807
 808 #if wxUSE_THREADS
 809     // if we are not in the main thread, output the assert directly and trap
 810     // since dialogs cannot be displayed
 811     if ( !wxThread::IsMain() )
 812     {
 813         msg += wxT(" [in child thread]");
 814
 815 #if defined(__WXMSW__) && !defined(__WXMICROWIN__)
 816         msg << wxT("\r\n");
 817         OutputDebugString(msg );
 818 #else
 819         // send to stderr
 820         wxFprintf(stderr, wxT("%s\n"), msg.c_str());
 821         fflush(stderr);
 822 #endif
 823         // He-e-e-e-elp!! we're asserting in a child thread
 824         wxTrap();
 825     }
 826     else
 827 #endif // wxUSE_THREADS
 828
 829     if ( !s_bNoAsserts )
 830     {
 831         // send it to the normal log destination
 832         wxLogDebug(_T("%s"), msg.c_str());
 833
 834         if ( traits )
 835         {
 836             // delegate showing assert dialog (if possible) to that class
 837             s_bNoAsserts = traits->ShowAssertDialog(msg);
 838         }
 839         else // no traits object
 840         {
 841             // fall back to the function of last resort
 842             s_bNoAsserts = DoShowAssertDialog(msg);
 843         }
 844     }
 845 }
 846
 847 #endif // __WXDEBUG__
 848