src/gtk/evtloop.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/gtk/evtloop.cpp
   3 // Purpose:     implements wxEventLoop for GTK+
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     10.07.01
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2001 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   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 #ifdef __BORLANDC__
  24     #pragma hdrstop
  25 #endif
  26
  27 #include "wx/evtloop.h"
  28 #include "wx/evtloopsrc.h"
  29
  30 #ifndef WX_PRECOMP
  31     #include "wx/app.h"
  32     #include "wx/log.h"
  33 #endif // WX_PRECOMP
  34
  35 #include "wx/private/eventloopsourcesmanager.h"
  36 #include "wx/apptrait.h"
  37
  38 #include <gtk/gtk.h>
  39 #include <glib.h>
  40
  41 // ============================================================================
  42 // wxEventLoop implementation
  43 // ============================================================================
  44
  45 extern GtkWidget *wxGetRootWindow();
  46
  47 // ----------------------------------------------------------------------------
  48 // wxEventLoop running and exiting
  49 // ----------------------------------------------------------------------------
  50
  51 wxGUIEventLoop::wxGUIEventLoop()
  52 {
  53     m_exitcode = 0;
  54 }
  55
  56 int wxGUIEventLoop::DoRun()
  57 {
  58     guint loopLevel = gtk_main_level();
  59
  60     // This is placed inside of a loop to take into account nested
  61     // event loops.  For example, inside this event loop, we may receive
  62     // Exit() for a different event loop (which we are currently inside of)
  63     // That Exit() will cause this gtk_main() to exit so we need to re-enter it.
  64     while ( !m_shouldExit )
  65     {
  66         gtk_main();
  67     }
  68
  69     // Force the enclosing event loop to also exit to see if it is done in case
  70     // that event loop had Exit() called inside of the just ended loop. If it
  71     // is not time yet for that event loop to exit, it will be executed again
  72     // due to the while() loop on m_shouldExit().
  73     //
  74     // This is unnecessary if we are the top level loop, i.e. loop of level 0.
  75     if ( loopLevel )
  76     {
  77         gtk_main_quit();
  78     }
  79
  80     OnExit();
  81
  82     return m_exitcode;
  83 }
  84
  85 void wxGUIEventLoop::ScheduleExit(int rc)
  86 {
  87     wxCHECK_RET( IsInsideRun(), wxT("can't call ScheduleExit() if not started") );
  88
  89     m_exitcode = rc;
  90
  91     m_shouldExit = true;
  92
  93     gtk_main_quit();
  94 }
  95
  96 void wxGUIEventLoop::WakeUp()
  97 {
  98     // TODO: idle events handling should really be done by wxEventLoop itself
  99     //       but for now it's completely in gtk/app.cpp so just call there when
 100     //       we have wxTheApp and hope that it doesn't matter that we do
 101     //       nothing when we don't...
 102     if ( wxTheApp )
 103         wxTheApp->WakeUpIdle();
 104 }
 105
 106 // ----------------------------------------------------------------------------
 107 // wxEventLoop adding & removing sources
 108 // ----------------------------------------------------------------------------
 109
 110 #if wxUSE_EVENTLOOP_SOURCE
 111
 112 extern "C"
 113 {
 114 static gboolean wx_on_channel_event(GIOChannel *channel,
 115                                     GIOCondition condition,
 116                                     gpointer data)
 117 {
 118     wxUnusedVar(channel); // Unused if !wxUSE_LOG || !wxDEBUG_LEVEL
 119
 120     wxLogTrace(wxTRACE_EVT_SOURCE,
 121                "wx_on_channel_event, fd=%d, condition=%08x",
 122                g_io_channel_unix_get_fd(channel), condition);
 123
 124     wxEventLoopSourceHandler * const
 125         handler = static_cast<wxEventLoopSourceHandler *>(data);
 126
 127     if (condition & G_IO_IN || condition & G_IO_PRI)
 128         handler->OnReadWaiting();
 129     if (condition & G_IO_OUT)
 130         handler->OnWriteWaiting();
 131     else if (condition & G_IO_ERR || condition & G_IO_NVAL)
 132         handler->OnExceptionWaiting();
 133
 134     // we never want to remove source here, so always return true
 135     return TRUE;
 136 }
 137 }
 138
 139 class wxGUIEventLoopSourcesManager : public wxEventLoopSourcesManagerBase
 140 {
 141 public:
 142     virtual wxEventLoopSource*
 143     AddSourceForFD(int fd, wxEventLoopSourceHandler *handler, int flags)
 144     {
 145         wxCHECK_MSG( fd != -1, NULL, "can't monitor invalid fd" );
 146
 147         int condition = 0;
 148         if ( flags & wxEVENT_SOURCE_INPUT )
 149             condition |= G_IO_IN | G_IO_PRI | G_IO_HUP;
 150         if ( flags & wxEVENT_SOURCE_OUTPUT )
 151             condition |= G_IO_OUT;
 152         if ( flags & wxEVENT_SOURCE_EXCEPTION )
 153             condition |= G_IO_ERR | G_IO_NVAL;
 154
 155         GIOChannel* channel = g_io_channel_unix_new(fd);
 156         const unsigned sourceId  = g_io_add_watch
 157                                    (
 158                                     channel,
 159                                     (GIOCondition)condition,
 160                                     &wx_on_channel_event,
 161                                     handler
 162                                    );
 163         // it was ref'd by g_io_add_watch() so we can unref it here
 164         g_io_channel_unref(channel);
 165
 166         if ( !sourceId )
 167             return NULL;
 168
 169         wxLogTrace(wxTRACE_EVT_SOURCE,
 170                    "Adding event loop source for fd=%d with GTK id=%u",
 171                    fd, sourceId);
 172
 173
 174         return new wxGTKEventLoopSource(sourceId, handler, flags);
 175     }
 176 };
 177
 178 wxEventLoopSourcesManagerBase* wxGUIAppTraits::GetEventLoopSourcesManager()
 179 {
 180     static wxGUIEventLoopSourcesManager s_eventLoopSourcesManager;
 181
 182     return &s_eventLoopSourcesManager;
 183 }
 184
 185 wxGTKEventLoopSource::~wxGTKEventLoopSource()
 186 {
 187     wxLogTrace(wxTRACE_EVT_SOURCE,
 188                "Removing event loop source with GTK id=%u", m_sourceId);
 189
 190     g_source_remove(m_sourceId);
 191 }
 192
 193 #endif // wxUSE_EVENTLOOP_SOURCE
 194
 195 // ----------------------------------------------------------------------------
 196 // wxEventLoop message processing dispatching
 197 // ----------------------------------------------------------------------------
 198
 199 bool wxGUIEventLoop::Pending() const
 200 {
 201     if ( wxTheApp )
 202     {
 203         // this avoids false positives from our idle source
 204         return wxTheApp->EventsPending();
 205     }
 206
 207     return gtk_events_pending() != 0;
 208 }
 209
 210 bool wxGUIEventLoop::Dispatch()
 211 {
 212     wxCHECK_MSG( IsRunning(), false, wxT("can't call Dispatch() if not running") );
 213
 214     // gtk_main_iteration() returns TRUE only if gtk_main_quit() was called
 215     return !gtk_main_iteration();
 216 }
 217
 218 extern "C" {
 219 static gboolean wx_event_loop_timeout(void* data)
 220 {
 221     bool* expired = static_cast<bool*>(data);
 222     *expired = true;
 223
 224     // return FALSE to remove this timeout
 225     return FALSE;
 226 }
 227 }
 228
 229 int wxGUIEventLoop::DispatchTimeout(unsigned long timeout)
 230 {
 231     bool expired = false;
 232     const unsigned id = g_timeout_add(timeout, wx_event_loop_timeout, &expired);
 233     bool quit = gtk_main_iteration() != 0;
 234
 235     if ( expired )
 236         return -1;
 237
 238     g_source_remove(id);
 239
 240     return !quit;
 241 }
 242
 243 //-----------------------------------------------------------------------------
 244 // YieldFor
 245 //-----------------------------------------------------------------------------
 246
 247 extern "C" {
 248 static void wxgtk_main_do_event(GdkEvent* event, void* data)
 249 {
 250     // categorize the GDK event according to wxEventCategory.
 251     // See http://library.gnome.org/devel/gdk/unstable/gdk-Events.html#GdkEventType
 252     // for more info.
 253
 254     // NOTE: GDK_* constants which were not present in the GDK2.0 can be tested for
 255     //       only at compile-time; when running the program (compiled with a recent GDK)
 256     //       on a system with an older GDK lib we can be sure there won't be problems
 257     //       because event->type will never assume those values corresponding to
 258     //       new event types (since new event types are always added in GDK with non
 259     //       conflicting values for ABI compatibility).
 260
 261     // Some events (currently only a single one) may be used for more than one
 262     // category, so we need 2 variables. The second one will remain "unknown"
 263     // in most cases.
 264     wxEventCategory cat = wxEVT_CATEGORY_UNKNOWN,
 265                     cat2 = wxEVT_CATEGORY_UNKNOWN;
 266     switch (event->type)
 267     {
 268     case GDK_SELECTION_REQUEST:
 269     case GDK_SELECTION_NOTIFY:
 270     case GDK_SELECTION_CLEAR:
 271     case GDK_OWNER_CHANGE:
 272         cat = wxEVT_CATEGORY_CLIPBOARD;
 273         break;
 274
 275     case GDK_KEY_PRESS:
 276     case GDK_KEY_RELEASE:
 277     case GDK_BUTTON_PRESS:
 278     case GDK_2BUTTON_PRESS:
 279     case GDK_3BUTTON_PRESS:
 280     case GDK_BUTTON_RELEASE:
 281     case GDK_SCROLL:        // generated from mouse buttons
 282     case GDK_CLIENT_EVENT:
 283         cat = wxEVT_CATEGORY_USER_INPUT;
 284         break;
 285
 286     case GDK_PROPERTY_NOTIFY:
 287         // This one is special: it can be used for UI purposes but also for
 288         // clipboard operations, so allow it in both cases (we probably could
 289         // examine the event itself to distinguish between the two cases but
 290         // this would be unnecessarily complicated).
 291         cat2 = wxEVT_CATEGORY_CLIPBOARD;
 292         // Fall through.
 293
 294     case GDK_PROXIMITY_IN:
 295     case GDK_PROXIMITY_OUT:
 296
 297     case GDK_MOTION_NOTIFY:
 298     case GDK_ENTER_NOTIFY:
 299     case GDK_LEAVE_NOTIFY:
 300     case GDK_VISIBILITY_NOTIFY:
 301
 302     case GDK_FOCUS_CHANGE:
 303     case GDK_CONFIGURE:
 304     case GDK_WINDOW_STATE:
 305     case GDK_SETTING:
 306     case GDK_DELETE:
 307     case GDK_DESTROY:
 308
 309     case GDK_EXPOSE:
 310 #ifndef __WXGTK3__
 311     case GDK_NO_EXPOSE:
 312 #endif
 313     case GDK_MAP:
 314     case GDK_UNMAP:
 315
 316     case GDK_DRAG_ENTER:
 317     case GDK_DRAG_LEAVE:
 318     case GDK_DRAG_MOTION:
 319     case GDK_DRAG_STATUS:
 320     case GDK_DROP_START:
 321     case GDK_DROP_FINISHED:
 322 #if GTK_CHECK_VERSION(2,8,0)
 323     case GDK_GRAB_BROKEN:
 324 #endif
 325 #if GTK_CHECK_VERSION(2,14,0)
 326     case GDK_DAMAGE:
 327 #endif
 328         cat = wxEVT_CATEGORY_UI;
 329         break;
 330
 331     default:
 332         cat = wxEVT_CATEGORY_UNKNOWN;
 333         break;
 334     }
 335
 336     wxGUIEventLoop* evtloop = static_cast<wxGUIEventLoop*>(data);
 337
 338     // is this event allowed now?
 339     if (evtloop->IsEventAllowedInsideYield(cat) ||
 340             (cat2 != wxEVT_CATEGORY_UNKNOWN &&
 341                 evtloop->IsEventAllowedInsideYield(cat2)))
 342     {
 343         // process it now
 344         gtk_main_do_event(event);
 345     }
 346     else if (event->type != GDK_NOTHING)
 347     {
 348         // process it later (but make a copy; the caller will free the event
 349         // pointer)
 350         evtloop->StoreGdkEventForLaterProcessing(gdk_event_copy(event));
 351     }
 352 }
 353 }
 354
 355 bool wxGUIEventLoop::YieldFor(long eventsToProcess)
 356 {
 357 #if wxUSE_THREADS
 358     if ( !wxThread::IsMain() )
 359     {
 360         // can't call gtk_main_iteration() from other threads like this
 361         return true;
 362     }
 363 #endif // wxUSE_THREADS
 364
 365     m_isInsideYield = true;
 366     m_eventsToProcessInsideYield = eventsToProcess;
 367
 368 #if wxUSE_LOG
 369     // disable log flushing from here because a call to wxYield() shouldn't
 370     // normally result in message boxes popping up &c
 371     wxLog::Suspend();
 372 #endif
 373
 374     // temporarily replace the global GDK event handler with our function, which
 375     // categorizes the events and using m_eventsToProcessInsideYield decides
 376     // if an event should be processed immediately or not
 377     // NOTE: this approach is better than using gdk_display_get_event() because
 378     //       gtk_main_iteration() does more than just calling gdk_display_get_event()
 379     //       and then call gtk_main_do_event()!
 380     //       In particular in this way we also process input from sources like
 381     //       GIOChannels (this is needed for e.g. wxGUIAppTraits::WaitForChild).
 382     gdk_event_handler_set(wxgtk_main_do_event, this, NULL);
 383     while (Pending())   // avoid false positives from our idle source
 384         gtk_main_iteration();
 385     gdk_event_handler_set ((GdkEventFunc)gtk_main_do_event, NULL, NULL);
 386
 387     // Process all pending events too, this is consistent with wxMSW behaviour
 388     // and the behaviour of wxGTK itself in the previous versions.
 389     if ( wxTheApp )
 390         wxTheApp->ProcessPendingEvents();
 391
 392     if (eventsToProcess != wxEVT_CATEGORY_CLIPBOARD)
 393     {
 394         // It's necessary to call ProcessIdle() to update the frames sizes which
 395         // might have been changed (it also will update other things set from
 396         // OnUpdateUI() which is a nice (and desired) side effect). But we
 397         // call ProcessIdle() only once since this is not meant for longish
 398         // background jobs (controlled by wxIdleEvent::RequestMore() and the
 399         // return value of Processidle().
 400         ProcessIdle();
 401     }
 402     //else: if we are inside ~wxClipboardSync() and we call ProcessIdle() and
 403     //      the user app contains an UI update handler which calls wxClipboard::IsSupported,
 404     //      then we fall into a never-ending loop...
 405
 406     // put all unprocessed GDK events back in the queue
 407     GdkDisplay* disp = gtk_widget_get_display(wxGetRootWindow());
 408     for (size_t i=0; i<m_arrGdkEvents.GetCount(); i++)
 409     {
 410         GdkEvent* ev = (GdkEvent*)m_arrGdkEvents[i];
 411
 412         // NOTE: gdk_display_put_event makes a copy of the event passed to it
 413         gdk_display_put_event(disp, ev);
 414         gdk_event_free(ev);
 415     }
 416
 417     m_arrGdkEvents.Clear();
 418
 419 #if wxUSE_LOG
 420     // let the logs be flashed again
 421     wxLog::Resume();
 422 #endif
 423
 424     m_isInsideYield = false;
 425
 426     return true;
 427 }