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