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