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