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