src/motif/evtloop.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        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 license
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "evtloop.h"
  22 #endif
  23
  24 #ifdef __VMS
  25 #define XtParent XTPARENT
  26 #define XtDisplay XTDISPLAY
  27 #endif
  28
  29 // For compilers that support precompilation, includes "wx.h".
  30 #include "wx/wxprec.h"
  31
  32 #ifndef WX_PRECOMP
  33 #endif //WX_PRECOMP
  34
  35 #include "wx/evtloop.h"
  36 #include "wx/event.h"
  37 #include "wx/app.h"
  38
  39 #ifdef __VMS__
  40 #pragma message disable nosimpint
  41 #endif
  42 #include <Xm/Xm.h>
  43 #include <X11/Xlib.h>
  44 #ifdef __VMS__
  45 #pragma message enable nosimpint
  46 #endif
  47
  48 #include "wx/motif/private.h"
  49
  50 static bool CheckForKeyUp(XEvent* event);
  51 static bool CheckForKeyDown(XEvent* event);
  52 static bool CheckForAccelerator(XEvent* event);
  53 static void ProcessXEvent(XEvent* event);
  54 static void wxBreakDispatch();
  55
  56 // ----------------------------------------------------------------------------
  57 // wxEventLoopImpl
  58 // ----------------------------------------------------------------------------
  59
  60 class WXDLLEXPORT wxEventLoopImpl
  61 {
  62 public:
  63     // ctor
  64     wxEventLoopImpl() { SetExitCode(0); }
  65
  66     // set/get the exit code
  67     void SetExitCode(int exitcode) { m_exitcode = exitcode; }
  68     int GetExitCode() const { return m_exitcode; }
  69
  70     bool SendIdleMessage();
  71     bool GetKeepGoing() const { return m_keepGoing; }
  72     void SetKeepGoing(bool keepGoing) { m_keepGoing = keepGoing; }
  73 private:
  74     // the exit code of the event loop
  75     int  m_exitcode;
  76     bool m_keepGoing;
  77 };
  78
  79 // ----------------------------------------------------------------------------
  80 // wxEventLoopImpl idle event processing
  81 // ----------------------------------------------------------------------------
  82
  83 static bool SendIdleMessage()
  84 {
  85     wxIdleEvent event;
  86
  87     return wxTheApp->ProcessEvent(event) && event.MoreRequested();
  88 }
  89
  90 bool wxEventLoopImpl::SendIdleMessage()
  91 {
  92     return ::SendIdleMessage();
  93 }
  94
  95 // ============================================================================
  96 // wxEventLoop implementation
  97 // ============================================================================
  98
  99 // ----------------------------------------------------------------------------
 100 // wxEventLoop running and exiting
 101 // ----------------------------------------------------------------------------
 102
 103 wxEventLoop *wxEventLoop::ms_activeLoop = NULL;
 104
 105 wxEventLoop::~wxEventLoop()
 106 {
 107     wxASSERT_MSG( !m_impl, _T("should have been deleted in Run()") );
 108 }
 109
 110 bool wxEventLoop::IsRunning() const
 111 {
 112     return m_impl != NULL;
 113 }
 114
 115 int wxEventLoop::Run()
 116 {
 117     // event loops are not recursive, you need to create another loop!
 118     wxCHECK_MSG( !IsRunning(), -1, _T("can't reenter a message loop") );
 119
 120     wxEventLoop *oldLoop = ms_activeLoop;
 121     ms_activeLoop = this;
 122
 123     m_impl = new wxEventLoopImpl;
 124     m_impl->SetKeepGoing( true );
 125
 126     for( ;; )
 127     {
 128         if( !wxDoEventLoopIteration( *this ) )
 129             break;
 130     }
 131
 132     int exitcode = m_impl->GetExitCode();
 133     delete m_impl;
 134     m_impl = NULL;
 135
 136     ms_activeLoop = oldLoop;
 137
 138     return exitcode;
 139 }
 140
 141 void wxEventLoop::Exit(int rc)
 142 {
 143     wxCHECK_RET( IsRunning(), _T("can't call Exit() if not running") );
 144
 145     m_impl->SetExitCode(rc);
 146     m_impl->SetKeepGoing( false );
 147
 148     ::wxBreakDispatch();
 149 }
 150
 151 // ----------------------------------------------------------------------------
 152 // wxEventLoop message processing dispatching
 153 // ----------------------------------------------------------------------------
 154
 155 bool wxEventLoop::Pending() const
 156 {
 157     return XtAppPending( (XtAppContext)wxTheApp->GetAppContext() ) != 0;
 158 }
 159
 160 bool wxEventLoop::Dispatch()
 161 {
 162     XEvent event;
 163     XtAppContext context = (XtAppContext)wxTheApp->GetAppContext();
 164
 165     if( XtAppPeekEvent( context, &event ) != 0 )
 166     {
 167         XtAppNextEvent( context, &event );
 168         ProcessXEvent( &event );
 169     }
 170     else
 171         XtAppProcessEvent( context, XtIMTimer|XtIMAlternateInput|XtIMSignal );
 172
 173     return m_impl ? m_impl->GetKeepGoing() : true;
 174 }
 175
 176 // ----------------------------------------------------------------------------
 177 // Static functions (originally in app.cpp)
 178 // ----------------------------------------------------------------------------
 179
 180 void ProcessXEvent(XEvent* event)
 181 {
 182     if (event->type == KeyPress)
 183     {
 184         if (CheckForAccelerator(event))
 185         {
 186             // Do nothing! We intercepted and processed the event as an
 187             // accelerator.
 188             return;
 189         }
 190         // It seemed before that this hack was redundant and
 191         // key down events were being generated by wxCanvasInputEvent.
 192         // But no longer - why ???
 193         //
 194         else if (CheckForKeyDown(event))
 195         {
 196             // We intercepted and processed the key down event
 197             return;
 198         }
 199         else
 200         {
 201             XtDispatchEvent(event);
 202             return;
 203         }
 204     }
 205     else if (event->type == KeyRelease)
 206     {
 207         // TODO: work out why we still need this !  -michael
 208         //
 209         if (::CheckForKeyUp(event))
 210         {
 211             // We intercepted and processed the key up event
 212             return;
 213         }
 214         else
 215         {
 216             XtDispatchEvent(event);
 217             return;
 218         }
 219     }
 220     else if (event->type == PropertyNotify)
 221     {
 222         wxTheApp->HandlePropertyChange(event);
 223         return;
 224     }
 225     else if (event->type == ResizeRequest)
 226     {
 227         /* Terry Gitnick <terryg@scientech.com> - 1/21/98
 228          * If resize event, don't resize until the last resize event for this
 229          * window is recieved. Prevents flicker as windows are resized.
 230          */
 231
 232         Display *disp = XtDisplay((Widget) wxTheApp->GetTopLevelWidget());
 233         Window win = event->xany.window;
 234         XEvent report;
 235
 236         //  to avoid flicker
 237         report = * event;
 238         while( XCheckTypedWindowEvent (disp, win, ResizeRequest, &report));
 239
 240         // TODO: when implementing refresh optimization, we can use
 241         // XtAddExposureToRegion to expand the window's paint region.
 242
 243         XtDispatchEvent(event);
 244     }
 245     else
 246     {
 247         XtDispatchEvent(event);
 248     }
 249 }
 250
 251 // Returns true if an accelerator has been processed
 252 bool CheckForAccelerator(XEvent* event)
 253 {
 254     if (event->xany.type == KeyPress)
 255     {
 256         // Find a wxWindow for this window
 257         // TODO: should get display for the window, not the current display
 258         Widget widget = XtWindowToWidget((Display*) wxGetDisplay(),
 259                                          event->xany.window);
 260         wxWindow* win = NULL;
 261
 262         // Find the first wxWindow that corresponds to this event window
 263         while (widget && !(win = wxGetWindowFromTable(widget)))
 264             widget = XtParent(widget);
 265
 266         if (!widget || !win)
 267             return false;
 268
 269         wxKeyEvent keyEvent(wxEVT_CHAR);
 270         wxTranslateKeyEvent(keyEvent, win, (Widget) 0, event);
 271
 272         // Now we have a wxKeyEvent and we have a wxWindow.
 273         // Go up the hierarchy until we find a matching accelerator,
 274         // or we get to the top.
 275         while (win)
 276         {
 277             if (win->ProcessAccelerator(keyEvent))
 278                 return true;
 279             win = win->GetParent();
 280         }
 281         return false;
 282     }
 283     return false;
 284 }
 285
 286 // bool wxApp::CheckForKeyDown(WXEvent* event) { wxFAIL; return false; }
 287
 288 bool CheckForKeyDown(XEvent* event)
 289 {
 290     if (event->xany.type == KeyPress)
 291     {
 292         Widget widget = XtWindowToWidget((Display*) wxGetDisplay(),
 293                      event->xany.window);
 294         wxWindow* win = NULL;
 295
 296         // Find the first wxWindow that corresponds to this event window
 297         while (widget && !(win = wxGetWindowFromTable(widget)))
 298             widget = XtParent(widget);
 299
 300         if (!widget || !win)
 301             return false;
 302
 303         wxKeyEvent keyEvent(wxEVT_KEY_DOWN);
 304         wxTranslateKeyEvent(keyEvent, win, (Widget) 0, event);
 305
 306         return win->ProcessEvent( keyEvent );
 307     }
 308
 309     return false;
 310 }
 311
 312 // bool wxApp::CheckForKeyUp(WXEvent* event) { wxFAIL; return false; }
 313
 314 bool CheckForKeyUp(XEvent* event)
 315 {
 316     if (event->xany.type == KeyRelease)
 317     {
 318         Widget widget = XtWindowToWidget((Display*) wxGetDisplay(),
 319                          event->xany.window);
 320         wxWindow* win = NULL;
 321
 322         // Find the first wxWindow that corresponds to this event window
 323         while (widget && !(win = wxGetWindowFromTable(widget)))
 324                 widget = XtParent(widget);
 325
 326         if (!widget || !win)
 327             return false;
 328
 329         wxKeyEvent keyEvent(wxEVT_KEY_UP);
 330         wxTranslateKeyEvent(keyEvent, win, (Widget) 0, event);
 331
 332         return win->ProcessEvent( keyEvent );
 333     }
 334
 335     return false;
 336 }
 337
 338 // ----------------------------------------------------------------------------
 339 // executes one main loop iteration (declared in include/wx/motif/private.h)
 340 // ----------------------------------------------------------------------------
 341
 342 bool wxDoEventLoopIteration( wxEventLoop& evtLoop )
 343 {
 344 #if wxUSE_THREADS
 345     // leave the main loop to give other threads a chance to
 346     // perform their GUI work
 347     wxMutexGuiLeave();
 348     wxUsleep(20);
 349     wxMutexGuiEnter();
 350 #endif
 351
 352     while ( !evtLoop.Pending() && ::SendIdleMessage() )
 353         ;
 354
 355     if( !evtLoop.Dispatch() )
 356         return false;
 357
 358     return true;
 359 }
 360
 361 // ----------------------------------------------------------------------------
 362 // ::wxWakeUpIdle implementation
 363 // ----------------------------------------------------------------------------
 364
 365 // As per Vadim's suggestion, we open a pipe, and XtAppAddInputSource it;
 366 // writing a single byte to the pipe will cause wxEventLoop::Pending
 367 // to return true, and wxEventLoop::Dispatch to dispatch an input handler
 368 // that simply removes the byte(s), and to return, which will cause
 369 // an idle event to be sent
 370
 371 // also wxEventLoop::Exit is implemented that way, so that exiting an
 372 // event loop won't require an event being in the queue
 373
 374 #include "wx/module.h"
 375
 376 #include <sys/types.h>
 377 #include <sys/time.h>
 378 #include <unistd.h>
 379
 380 static XtInputId inputId;
 381 static int idleFds[2] = { -1, -1 };
 382
 383 class wxIdlePipeModule : public wxModule
 384 {
 385 public:
 386     wxIdlePipeModule() {};
 387
 388     virtual bool OnInit()
 389     {
 390         if( pipe(idleFds) != 0 )
 391             return false;
 392
 393         return true;
 394     }
 395
 396     virtual void OnExit()
 397     {
 398         close( idleFds[0] );
 399         close( idleFds[1] );
 400     }
 401 private:
 402     DECLARE_DYNAMIC_CLASS(wxIdlePipeModule);
 403 };
 404
 405 IMPLEMENT_DYNAMIC_CLASS(wxIdlePipeModule, wxModule);
 406
 407 static void wxInputCallback( XtPointer, int* fd, XtInputId* )
 408 {
 409     char buffer[128];
 410
 411     // wxWakeUpIdle may have been called more than once
 412     for(;;)
 413     {
 414         fd_set in;
 415         struct timeval timeout;
 416
 417         timeout.tv_sec = 0;
 418         timeout.tv_usec = 0;
 419
 420         FD_ZERO( &in );
 421         FD_SET( *fd, &in );
 422
 423         if( select( *fd + 1, &in, NULL, NULL, &timeout ) <= 0 )
 424             break;
 425         if( read( *fd, buffer, sizeof(buffer) - 1 ) != sizeof(buffer) - 1 )
 426             break;
 427     }
 428 }
 429
 430 static void wxBreakDispatch()
 431 {
 432     char dummy;
 433
 434     // check if wxWakeUpIdle has already been called
 435     fd_set in;
 436     struct timeval timeout;
 437
 438     timeout.tv_sec = 0;
 439     timeout.tv_usec = 0;
 440
 441     FD_ZERO( &in );
 442     FD_SET( idleFds[0], &in );
 443
 444     if( select( idleFds[0] + 1, &in, NULL, NULL, &timeout ) > 0 )
 445         return;
 446
 447     // write a single byte
 448     write( idleFds[1], &dummy, 1 );
 449 }
 450
 451 void wxWakeUpIdle()
 452 {
 453     ::wxBreakDispatch();
 454 }
 455
 456 bool wxAddIdleCallback()
 457 {
 458     // install input handler for wxWakeUpIdle
 459     inputId = XtAppAddInput( (XtAppContext) wxTheApp->GetAppContext(),
 460                              idleFds[0],
 461                              (XtPointer)XtInputReadMask,
 462                              wxInputCallback,
 463                              NULL );
 464
 465     return true;
 466 }
 467