src/unix/epolldispatcher.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/epolldispatcher.cpp
   3 // Purpose:     implements dispatcher for epoll_wait() call
   4 // Author:      Lukasz Michalski
   5 // Created:     April 2007
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2007 Lukasz Michalski
   8 // License:     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_EPOLL_DISPATCHER
  23
  24 #include "wx/unix/private/epolldispatcher.h"
  25 #include "wx/unix/private.h"
  26
  27 #ifndef WX_PRECOMP
  28     #include "wx/log.h"
  29     #include "wx/intl.h"
  30 #endif
  31
  32 #include <sys/epoll.h>
  33 #include <errno.h>
  34 #include <unistd.h>
  35
  36 #define wxEpollDispatcher_Trace wxT("epolldispatcher")
  37
  38 // ============================================================================
  39 // implementation
  40 // ============================================================================
  41
  42 // helper: return EPOLLxxx mask corresponding to the given flags (and also log
  43 // debugging messages about it)
  44 static uint32_t GetEpollMask(int flags, int fd)
  45 {
  46     uint32_t ep = 0;
  47
  48     if ( flags & wxFDIO_INPUT )
  49     {
  50         ep |= EPOLLIN;
  51         wxLogTrace(wxEpollDispatcher_Trace,
  52                    _T("Registered fd %d for input events"), fd);
  53     }
  54
  55     if ( flags & wxFDIO_OUTPUT )
  56     {
  57         ep |= EPOLLOUT;
  58         wxLogTrace(wxEpollDispatcher_Trace,
  59                    _T("Registered fd %d for output events"), fd);
  60     }
  61
  62     if ( flags & wxFDIO_EXCEPTION )
  63     {
  64         ep |= EPOLLERR | EPOLLHUP;
  65         wxLogTrace(wxEpollDispatcher_Trace,
  66                    _T("Registered fd %d for exceptional events"), fd);
  67     }
  68
  69     return ep;
  70 }
  71
  72 // ----------------------------------------------------------------------------
  73 // wxEpollDispatcher
  74 // ----------------------------------------------------------------------------
  75
  76 /* static */
  77 wxEpollDispatcher *wxEpollDispatcher::Create()
  78 {
  79     int epollDescriptor = epoll_create(1024);
  80     if ( epollDescriptor == -1 )
  81     {
  82         wxLogSysError(_("Failed to create epoll descriptor"));
  83         return NULL;
  84     }
  85
  86     return new wxEpollDispatcher(epollDescriptor);
  87 }
  88
  89 wxEpollDispatcher::wxEpollDispatcher(int epollDescriptor)
  90 {
  91     wxASSERT_MSG( epollDescriptor != -1, _T("invalid descriptor") );
  92
  93     m_epollDescriptor = epollDescriptor;
  94 }
  95
  96 wxEpollDispatcher::~wxEpollDispatcher()
  97 {
  98     if ( close(m_epollDescriptor) != 0 )
  99     {
 100         wxLogSysError(_("Error closing epoll descriptor"));
 101     }
 102 }
 103
 104 bool wxEpollDispatcher::RegisterFD(int fd, wxFDIOHandler* handler, int flags)
 105 {
 106     epoll_event ev;
 107     ev.events = GetEpollMask(flags, fd);
 108     ev.data.ptr = handler;
 109
 110     const int ret = epoll_ctl(m_epollDescriptor, EPOLL_CTL_ADD, fd, &ev);
 111     if ( ret != 0 )
 112     {
 113         wxLogSysError(_("Failed to add descriptor %d to epoll descriptor %d"),
 114                       fd, m_epollDescriptor);
 115
 116         return false;
 117     }
 118
 119     return true;
 120 }
 121
 122 bool wxEpollDispatcher::ModifyFD(int fd, wxFDIOHandler* handler, int flags)
 123 {
 124     epoll_event ev;
 125     ev.events = GetEpollMask(flags, fd);
 126     ev.data.ptr = handler;
 127
 128     const int ret = epoll_ctl(m_epollDescriptor, EPOLL_CTL_MOD, fd, &ev);
 129     if ( ret != 0 )
 130     {
 131         wxLogSysError(_("Failed to modify descriptor %d in epoll descriptor %d"),
 132                       fd, m_epollDescriptor);
 133
 134         return false;
 135     }
 136
 137     return true;
 138 }
 139
 140 bool wxEpollDispatcher::UnregisterFD(int fd)
 141 {
 142     epoll_event ev;
 143     ev.events = 0;
 144     ev.data.ptr = NULL;
 145
 146     if ( epoll_ctl(m_epollDescriptor, EPOLL_CTL_DEL, fd, &ev) != 0 )
 147     {
 148         wxLogSysError(_("Failed to unregister descriptor %d from epoll descriptor %d"),
 149                       fd, m_epollDescriptor);
 150     }
 151
 152     return true;
 153 }
 154
 155 void wxEpollDispatcher::Dispatch(int timeout)
 156 {
 157     epoll_event events[16];
 158
 159     const int e_num = epoll_wait
 160                       (
 161                         m_epollDescriptor,
 162                         events,
 163                         WXSIZEOF(events),
 164                         timeout == TIMEOUT_INFINITE ? -1 : timeout
 165                       );
 166
 167     if ( e_num == -1 )
 168     {
 169         if ( errno != EINTR )
 170         {
 171             wxLogSysError(_("Waiting for IO on epoll descriptor %d failed"),
 172                           m_epollDescriptor);
 173             return;
 174         }
 175     }
 176
 177     for ( epoll_event *p = events; p < events + e_num; p++ )
 178     {
 179         wxFDIOHandler * const handler = (wxFDIOHandler *)(p->data.ptr);
 180         if ( !handler )
 181         {
 182             wxFAIL_MSG( _T("NULL handler in epoll_event?") );
 183             continue;
 184         }
 185
 186         if ( p->events & EPOLLIN )
 187             handler->OnReadWaiting();
 188         else if ( p->events & EPOLLOUT )
 189             handler->OnWriteWaiting();
 190         else if ( p->events & (EPOLLERR | EPOLLHUP) )
 191             handler->OnExceptionWaiting();
 192     }
 193 }
 194
 195 #endif // wxUSE_EPOLL_DISPATCHER