src/unix/evtloopunix.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/unix/evtloopunix.cpp
   3 // Purpose:     wxEventLoop implementation
   4 // Author:      Lukasz Michalski (lm@zork.pl)
   5 // Created:     2007-05-07
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2006 Zork Lukasz Michalski
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 // ===========================================================================
  12 // declarations
  13 // ===========================================================================
  14
  15 // ---------------------------------------------------------------------------
  16 // headers
  17 // ---------------------------------------------------------------------------
  18
  19 // For compilers that support precompilation, includes "wx.h".
  20 #include "wx/wxprec.h"
  21
  22 #include "wx/evtloop.h"
  23
  24 #ifndef WX_PRECOMP
  25     #include "wx/app.h"
  26     #include "wx/log.h"
  27 #endif
  28
  29 #include <errno.h>
  30 #include "wx/thread.h"
  31 #include "wx/module.h"
  32 #include "wx/unix/private/epolldispatcher.h"
  33 #include "wx/private/selectdispatcher.h"
  34
  35 #if wxUSE_TIMER
  36     #include "wx/generic/private/timer.h"
  37 #endif
  38
  39 #define TRACE_EVENTS _T("events")
  40
  41 //this code should not be compiled when GUI is defined
  42 //(monolithic build issue)
  43 #if !wxUSE_GUI
  44
  45 // ===========================================================================
  46 // wxEventLoop::PipeIOHandler implementation
  47 // ===========================================================================
  48
  49 // ----------------------------------------------------------------------------
  50 // initialization
  51 // ----------------------------------------------------------------------------
  52
  53 bool wxConsoleEventLoop::PipeIOHandler::Create()
  54 {
  55     if ( !m_pipe.Create() )
  56     {
  57         wxLogError(_("Failed to create wake up pipe used by event loop."));
  58         return false;
  59     }
  60
  61     const int fdRead = GetReadFd();
  62
  63     int flags = fcntl(fdRead, F_GETFL, 0);
  64     if ( flags == -1 || fcntl(fdRead, F_SETFL, flags | O_NONBLOCK) == -1 )
  65     {
  66         wxLogSysError(_("Failed to switch wake up pipe to non-blocking mode"));
  67         return false;
  68     }
  69
  70     wxLogTrace(TRACE_EVENTS, wxT("Wake up pipe (%d, %d) created"),
  71                fdRead, m_pipe[wxPipe::Write]);
  72
  73     return true;
  74 }
  75
  76 // ----------------------------------------------------------------------------
  77 // wakeup handling
  78 // ----------------------------------------------------------------------------
  79
  80 void wxConsoleEventLoop::PipeIOHandler::WakeUp()
  81 {
  82     if ( write(m_pipe[wxPipe::Write], "s", 1) != 1 )
  83     {
  84         // don't use wxLog here, we can be in another thread and this could
  85         // result in dead locks
  86         perror("write(wake up pipe)");
  87     }
  88 }
  89
  90 void wxConsoleEventLoop::PipeIOHandler::OnReadWaiting()
  91 {
  92     // got wakeup from child thread: read all data available in pipe just to
  93     // make it empty (evevn though we write one byte at a time from WakeUp(),
  94     // it could have been called several times)
  95     char buf[4];
  96     for ( ;; )
  97     {
  98         const int size = read(GetReadFd(), buf, WXSIZEOF(buf));
  99
 100         if ( size == 0 || (size == -1 && errno == EAGAIN) )
 101         {
 102             // nothing left in the pipe (EAGAIN is expected for an FD with
 103             // O_NONBLOCK)
 104             break;
 105         }
 106
 107         if ( size == -1 )
 108         {
 109             wxLogSysError(_("Failed to read from wake-up pipe"));
 110
 111             break;
 112         }
 113     }
 114
 115     wxTheApp->ProcessPendingEvents();
 116 }
 117
 118 // ===========================================================================
 119 // wxEventLoop implementation
 120 // ===========================================================================
 121
 122 //-----------------------------------------------------------------------------
 123 // initialization
 124 //-----------------------------------------------------------------------------
 125
 126 wxConsoleEventLoop::wxConsoleEventLoop()
 127 {
 128     if ( !m_wakeupPipe.Create() )
 129     {
 130         m_dispatcher = NULL;
 131         return;
 132     }
 133
 134 #ifdef HAVE_SYS_EPOLL_H
 135     m_dispatcher = wxEpollDispatcher::Get();
 136     if ( !m_dispatcher )
 137 #endif // HAVE_SYS_EPOLL_H
 138     {
 139         m_dispatcher = wxSelectDispatcher::Get();
 140     }
 141
 142     wxCHECK_RET( m_dispatcher, _T("failed to create IO dispatcher") );
 143
 144     m_dispatcher->RegisterFD
 145                   (
 146                     m_wakeupPipe.GetReadFd(),
 147                     &m_wakeupPipe,
 148                     wxFDIO_INPUT
 149                   );
 150 };
 151
 152 //-----------------------------------------------------------------------------
 153 // events dispatch and loop handling
 154 //-----------------------------------------------------------------------------
 155
 156 bool wxConsoleEventLoop::Pending() const
 157 {
 158     return wxTheApp->HasPendingEvents();
 159 }
 160
 161 bool wxConsoleEventLoop::Dispatch()
 162 {
 163     wxTheApp->ProcessPendingEvents();
 164     return true;
 165 }
 166
 167 void wxConsoleEventLoop::WakeUp()
 168 {
 169     m_wakeupPipe.WakeUp();
 170 }
 171
 172 void wxConsoleEventLoop::OnNextIteration()
 173 {
 174     // calculate the timeout until the next timer expiration
 175     int timeout;
 176
 177 #if wxUSE_TIMER
 178     wxUsecClock_t nextTimer;
 179     if ( wxTimerScheduler::Get().GetNext(&nextTimer) )
 180     {
 181         // timeout is in ms
 182         timeout = (nextTimer / 1000).ToLong();
 183     }
 184     else // no timers, we can block forever
 185 #endif // wxUSE_TIMER
 186     {
 187         timeout = wxFDIODispatcher::TIMEOUT_INFINITE;
 188     }
 189
 190     m_dispatcher->RunLoop(timeout);
 191
 192 #if wxUSE_TIMER
 193     wxTimerScheduler::Get().NotifyExpired();
 194 #endif
 195
 196     // call the signal handlers for any signals we caught recently
 197     wxTheApp->CheckSignal();
 198 }
 199
 200 #endif // !wxUSE_GUI