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