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