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