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