src/motif/evtloop.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/motif/evtloop.cpp
   3 // Purpose:     implements wxEventLoop for Motif
   4 // Author:      Mattia Barbon
   5 // Modified by:
   6 // Created:     01.11.02
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2002 Mattia Barbon
   9 // License:     wxWindows licence
  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 #ifndef WX_PRECOMP
  24     #include "wx/event.h"
  25     #include "wx/app.h"
  26     #include "wx/window.h"
  27     #include "wx/module.h"
  28 #endif //WX_PRECOMP
  29
  30 #include "wx/evtloop.h"
  31 #include "wx/thread.h"
  32
  33 #ifdef __VMS__
  34     #pragma message disable nosimpint
  35 #endif
  36 #include <Xm/Xm.h>
  37 #include <X11/Xlib.h>
  38 #ifdef __VMS__
  39     #pragma message enable nosimpint
  40 #endif
  41
  42 #include "wx/unix/private.h"
  43 #include "wx/motif/private.h"
  44
  45 #ifdef HAVE_SYS_SELECT_H
  46 #   include <sys/select.h>
  47 #endif
  48
  49 static bool CheckForKeyUp(XEvent* event);
  50 static bool CheckForKeyDown(XEvent* event);
  51 static bool CheckForAccelerator(XEvent* event);
  52 static void ProcessXEvent(XEvent* event);
  53 static void wxBreakDispatch();
  54
  55 // ----------------------------------------------------------------------------
  56 // wxEventLoopImpl
  57 // ----------------------------------------------------------------------------
  58
  59 class WXDLLEXPORT wxEventLoopImpl
  60 {
  61 public:
  62     // ctor
  63     wxEventLoopImpl() { SetExitCode(0); }
  64
  65     // set/get the exit code
  66     void SetExitCode(int exitcode) { m_exitcode = exitcode; }
  67     int GetExitCode() const { return m_exitcode; }
  68
  69     bool SendIdleMessage();
  70     bool GetKeepGoing() const { return m_keepGoing; }
  71     void SetKeepGoing(bool keepGoing) { m_keepGoing = keepGoing; }
  72 private:
  73     // the exit code of the event loop
  74     int  m_exitcode;
  75     bool m_keepGoing;
  76 };
  77
  78 // ----------------------------------------------------------------------------
  79 // wxEventLoopImpl idle event processing
  80 // ----------------------------------------------------------------------------
  81
  82 static bool SendIdleMessage()
  83 {
  84     return wxTheApp->ProcessIdle();
  85 }
  86
  87 bool wxEventLoopImpl::SendIdleMessage()
  88 {
  89     return ::SendIdleMessage();
  90 }
  91
  92 // ============================================================================
  93 // wxEventLoop implementation
  94 // ============================================================================
  95
  96 // ----------------------------------------------------------------------------
  97 // wxEventLoop running and exiting
  98 // ----------------------------------------------------------------------------
  99
 100 wxGUIEventLoop::~wxGUIEventLoop()
 101 {
 102     wxASSERT_MSG( !m_impl, _T("should have been deleted in Run()") );
 103 }
 104
 105 int wxGUIEventLoop::Run()
 106 {
 107     // event loops are not recursive, you need to create another loop!
 108     wxCHECK_MSG( !IsRunning(), -1, _T("can't reenter a message loop") );
 109
 110     wxEventLoopActivator activate(this);
 111
 112     m_impl = new wxEventLoopImpl;
 113     m_impl->SetKeepGoing( true );
 114
 115     for( ;; )
 116     {
 117         if( !wxDoEventLoopIteration( *this ) )
 118             break;
 119     }
 120
 121     OnExit();
 122
 123     int exitcode = m_impl->GetExitCode();
 124     delete m_impl;
 125     m_impl = NULL;
 126
 127     return exitcode;
 128 }
 129
 130 void wxGUIEventLoop::Exit(int rc)
 131 {
 132     wxCHECK_RET( IsRunning(), _T("can't call Exit() if not running") );
 133
 134     m_impl->SetExitCode(rc);
 135     m_impl->SetKeepGoing( false );
 136
 137     ::wxBreakDispatch();
 138 }
 139
 140 bool wxGUIEventLoop::YieldFor(long eventsToProcess)
 141 {
 142     m_isInsideYield = true;
 143     m_eventsToProcessInsideYield = eventsToProcess;
 144
 145     while (wxTheApp && wxTheApp->Pending())
 146         // TODO: implement event filtering using the eventsToProcess mask
 147         wxTheApp->Dispatch();
 148
 149     m_isInsideYield = false;
 150
 151     return true;
 152 }
 153
 154 // ----------------------------------------------------------------------------
 155 // wxEventLoop message processing dispatching
 156 // ----------------------------------------------------------------------------
 157
 158 bool wxGUIEventLoop::Pending() const
 159 {
 160     return XtAppPending( (XtAppContext)wxTheApp->GetAppContext() ) != 0;
 161 }
 162
 163 bool wxGUIEventLoop::Dispatch()
 164 {
 165     XEvent event;
 166     XtAppContext context = (XtAppContext)wxTheApp->GetAppContext();
 167
 168     if( XtAppPeekEvent( context, &event ) != 0 )
 169     {
 170         XtAppNextEvent( context, &event );
 171         ProcessXEvent( &event );
 172     }
 173     else
 174     {
 175         XtAppProcessEvent( context, XtIMTimer | XtIMAlternateInput
 176 #ifdef XtIMSignal
 177                            | XtIMSignal
 178 #endif
 179                          );
 180     }
 181
 182     return m_impl ? m_impl->GetKeepGoing() : true;
 183 }
 184
 185 // ----------------------------------------------------------------------------
 186 // Static functions (originally in app.cpp)
 187 // ----------------------------------------------------------------------------
 188
 189 void ProcessXEvent(XEvent* event)
 190 {
 191     if (event->type == KeyPress)
 192     {
 193         if (CheckForAccelerator(event))
 194         {
 195             // Do nothing! We intercepted and processed the event as an
 196             // accelerator.
 197             return;
 198         }
 199         // It seemed before that this hack was redundant and
 200         // key down events were being generated by wxCanvasInputEvent.
 201         // But no longer - why ???
 202         //
 203         else if (CheckForKeyDown(event))
 204         {
 205             // We intercepted and processed the key down event
 206             return;
 207         }
 208         else
 209         {
 210             XtDispatchEvent(event);
 211             return;
 212         }
 213     }
 214     else if (event->type == KeyRelease)
 215     {
 216         // TODO: work out why we still need this !  -michael
 217         //
 218         if (::CheckForKeyUp(event))
 219         {
 220             // We intercepted and processed the key up event
 221             return;
 222         }
 223         else
 224         {
 225             XtDispatchEvent(event);
 226             return;
 227         }
 228     }
 229     else if (event->type == PropertyNotify)
 230     {
 231         wxTheApp->HandlePropertyChange(event);
 232         return;
 233     }
 234     else if (event->type == ResizeRequest)
 235     {
 236         /* Terry Gitnick <terryg@scientech.com> - 1/21/98
 237          * If resize event, don't resize until the last resize event for this
 238          * window is recieved. Prevents flicker as windows are resized.
 239          */
 240
 241         Display *disp = event->xany.display;
 242         Window win = event->xany.window;
 243         XEvent report;
 244
 245         //  to avoid flicker
 246         report = * event;
 247         while( XCheckTypedWindowEvent (disp, win, ResizeRequest, &report));
 248
 249         // TODO: when implementing refresh optimization, we can use
 250         // XtAddExposureToRegion to expand the window's paint region.
 251
 252         XtDispatchEvent(event);
 253     }
 254     else
 255     {
 256         XtDispatchEvent(event);
 257     }
 258 }
 259
 260 // Returns true if an accelerator has been processed
 261 bool CheckForAccelerator(XEvent* event)
 262 {
 263     if (event->xany.type == KeyPress)
 264     {
 265         // Find a wxWindow for this window
 266         // TODO: should get display for the window, not the current display
 267         Widget widget = XtWindowToWidget(event->xany.display,
 268                                          event->xany.window);
 269         wxWindow* win = NULL;
 270
 271         // Find the first wxWindow that corresponds to this event window
 272         while (widget && ((win = wxGetWindowFromTable(widget))!=NULL))
 273             widget = XtParent(widget);
 274
 275         if (!widget || !win)
 276             return false;
 277
 278         wxKeyEvent keyEvent(wxEVT_CHAR);
 279         wxTranslateKeyEvent(keyEvent, win, (Widget) 0, event);
 280
 281         // Now we have a wxKeyEvent and we have a wxWindow.
 282         // Go up the hierarchy until we find a matching accelerator,
 283         // or we get to the top.
 284         while (win)
 285         {
 286             if (win->ProcessAccelerator(keyEvent))
 287                 return true;
 288             win = win->GetParent();
 289         }
 290         return false;
 291     }
 292     return false;
 293 }
 294
 295 // bool wxApp::CheckForKeyDown(WXEvent* event) { wxFAIL; return false; }
 296
 297 bool CheckForKeyDown(XEvent* event)
 298 {
 299     if (event->xany.type == KeyPress)
 300     {
 301         Widget widget = XtWindowToWidget(event->xany.display,
 302                                          event->xany.window);
 303         wxWindow* win = NULL;
 304
 305         // Find the first wxWindow that corresponds to this event window
 306         while (widget && ((win = wxGetWindowFromTable(widget))!=NULL))
 307             widget = XtParent(widget);
 308
 309         if (!widget || !win)
 310             return false;
 311
 312         wxKeyEvent keyEvent(wxEVT_KEY_DOWN);
 313         wxTranslateKeyEvent(keyEvent, win, (Widget) 0, event);
 314
 315         return win->HandleWindowEvent( keyEvent );
 316     }
 317
 318     return false;
 319 }
 320
 321 // bool wxApp::CheckForKeyUp(WXEvent* event) { wxFAIL; return false; }
 322
 323 bool CheckForKeyUp(XEvent* event)
 324 {
 325     if (event->xany.type == KeyRelease)
 326     {
 327         Widget widget = XtWindowToWidget(event->xany.display,
 328                                          event->xany.window);
 329         wxWindow* win = NULL;
 330
 331         // Find the first wxWindow that corresponds to this event window
 332         while (widget && ((win = wxGetWindowFromTable(widget))!=NULL))
 333                 widget = XtParent(widget);
 334
 335         if (!widget || !win)
 336             return false;
 337
 338         wxKeyEvent keyEvent(wxEVT_KEY_UP);
 339         wxTranslateKeyEvent(keyEvent, win, (Widget) 0, event);
 340
 341         return win->HandleWindowEvent( keyEvent );
 342     }
 343
 344     return false;
 345 }
 346
 347 // ----------------------------------------------------------------------------
 348 // executes one main loop iteration (declared in include/wx/motif/private.h)
 349 // ----------------------------------------------------------------------------
 350
 351 bool wxDoEventLoopIteration( wxGUIEventLoop& evtLoop )
 352 {
 353     bool moreRequested, pendingEvents;
 354
 355     for(;;)
 356     {
 357         pendingEvents = evtLoop.Pending();
 358         if( pendingEvents ) break;
 359         moreRequested = ::SendIdleMessage();
 360         if( !moreRequested ) break;
 361     }
 362
 363 #if wxUSE_THREADS
 364     if( !pendingEvents && !moreRequested )
 365     {
 366         // leave the main loop to give other threads a chance to
 367         // perform their GUI work
 368         wxMutexGuiLeave();
 369         wxMilliSleep(20);
 370         wxMutexGuiEnter();
 371     }
 372 #endif
 373
 374     if( !evtLoop.Dispatch() )
 375         return false;
 376
 377     return true;
 378 }
 379
 380 // ----------------------------------------------------------------------------
 381 // ::wxWakeUpIdle implementation
 382 // ----------------------------------------------------------------------------
 383
 384 // As per Vadim's suggestion, we open a pipe, and XtAppAddInputSource it;
 385 // writing a single byte to the pipe will cause wxEventLoop::Pending
 386 // to return true, and wxEventLoop::Dispatch to dispatch an input handler
 387 // that simply removes the byte(s), and to return, which will cause
 388 // an idle event to be sent
 389
 390 // also wxEventLoop::Exit is implemented that way, so that exiting an
 391 // event loop won't require an event being in the queue
 392
 393 #include <sys/types.h>
 394 #include <sys/time.h>
 395 #include <unistd.h>
 396
 397 static int idleFds[2] = { -1, -1 };
 398
 399 class wxIdlePipeModule : public wxModule
 400 {
 401 public:
 402     wxIdlePipeModule() {};
 403
 404     virtual bool OnInit()
 405     {
 406         // Must be done before modules are initialized
 407 #if 0
 408         if( pipe(idleFds) != 0 )
 409             return false;
 410 #endif
 411         return true;
 412     }
 413
 414     virtual void OnExit()
 415     {
 416         close( idleFds[0] );
 417         close( idleFds[1] );
 418     }
 419 private:
 420     DECLARE_DYNAMIC_CLASS(wxIdlePipeModule)
 421 };
 422
 423 IMPLEMENT_DYNAMIC_CLASS(wxIdlePipeModule, wxModule)
 424
 425 static void wxInputCallback( XtPointer, int* fd, XtInputId* )
 426 {
 427     char buffer[128];
 428
 429     // wxWakeUpIdle may have been called more than once
 430     for(;;)
 431     {
 432         fd_set in;
 433         struct timeval timeout;
 434
 435         timeout.tv_sec = 0;
 436         timeout.tv_usec = 0;
 437
 438         wxFD_ZERO( &in );
 439         wxFD_SET( *fd, &in );
 440
 441         if( select( *fd + 1, &in, NULL, NULL, &timeout ) <= 0 )
 442             break;
 443         if( read( *fd, buffer, sizeof(buffer) - 1 ) != sizeof(buffer) - 1 )
 444             break;
 445     }
 446 }
 447
 448 static void wxBreakDispatch()
 449 {
 450     char dummy = 0; // for valgrind
 451
 452     // check if wxWakeUpIdle has already been called
 453     fd_set in;
 454     struct timeval timeout;
 455
 456     timeout.tv_sec = 0;
 457     timeout.tv_usec = 0;
 458
 459     wxFD_ZERO( &in );
 460     wxFD_SET( idleFds[0], &in );
 461
 462     if( select( idleFds[0] + 1, &in, NULL, NULL, &timeout ) > 0 )
 463         return;
 464
 465     // write a single byte
 466     write( idleFds[1], &dummy, 1 );
 467 }
 468
 469 void wxApp::WakeUpIdle()
 470 {
 471     ::wxBreakDispatch();
 472 }
 473
 474 bool wxInitIdleFds()
 475 {
 476     if( pipe(idleFds) != 0 )
 477         return false;
 478     return true;
 479 }
 480
 481 bool wxAddIdleCallback()
 482 {
 483     if (!wxInitIdleFds())
 484         return false;
 485
 486     // install input handler for wxWakeUpIdle
 487     XtAppAddInput((XtAppContext) wxTheApp->GetAppContext(),
 488                   idleFds[0],
 489                   (XtPointer)XtInputReadMask,
 490                   wxInputCallback,
 491                   NULL);
 492
 493     return true;
 494 }