src/socketengines/socketengine_select.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *          the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #ifndef WINDOWS
  16 #include <sys/select.h>
  17 #endif // WINDOWS
  18 #include "socketengines/socketengine_select.h"
  19
  20
  21 SelectEngine::SelectEngine()
  22 {
  23         MAX_DESCRIPTORS = FD_SETSIZE;
  24         CurrentSetSize = 0;
  25
  26         ref = new EventHandler* [GetMaxFds()];
  27         memset(ref, 0, GetMaxFds() * sizeof(EventHandler*));
  28 }
  29
  30 SelectEngine::~SelectEngine()
  31 {
  32         delete[] ref;
  33 }
  34
  35 bool SelectEngine::AddFd(EventHandler* eh, int)
  36 {
  37         int fd = eh->GetFd();
  38         if ((fd < 0) || (fd > GetMaxFds() - 1))
  39                 return false;
  40
  41         if (ref[fd])
  42                 return false;
  43
  44         ref[fd] = eh;
  45         SocketEngine::SetEventMask(eh, event_mask);
  46         CurrentSetSize++;
  47
  48         ServerInstance->Logs->Log("SOCKET",DEBUG,"New file descriptor: %d", fd);
  49         return true;
  50 }
  51
  52 bool SelectEngine::DelFd(EventHandler* eh, bool force)
  53 {
  54         int fd = eh->GetFd();
  55
  56         if ((fd < 0) || (fd > GetMaxFds() - 1))
  57                 return false;
  58
  59         CurrentSetSize--;
  60         ref[fd] = NULL;
  61
  62         ServerInstance->Logs->Log("SOCKET",DEBUG,"Remove file descriptor: %d", fd);
  63         return true;
  64 }
  65
  66 void SelectEngine::OnSetEvent(EventHandler* eh, int old_mask, int new_mask)
  67 {
  68         // deal with it later
  69 }
  70
  71 int SelectEngine::DispatchEvents()
  72 {
  73         timeval tval;
  74         int sresult = 0;
  75         socklen_t codesize = sizeof(int);
  76         int errcode = 0;
  77
  78         fd_set wfdset, rfdset, errfdset;
  79         FD_ZERO(&wfdset);
  80         FD_ZERO(&rfdset);
  81         FD_ZERO(&errfdset);
  82
  83         /* Populate the select FD sets (this is why select sucks compared to epoll, kqueue, IOCP) */
  84         for (int i = 0; i < FD_SETSIZE; i++)
  85         {
  86                 EventHandler* eh = ref[i];
  87                 if (!eh)
  88                         continue;
  89                 int state = eh->GetEventMask();
  90                 if (state & (FD_WANT_POLL_READ | FD_WANT_FAST_READ))
  91                         FD_SET (i, &rfdset);
  92                 if (state & (FD_WANT_POLL_WRITE | FD_WANT_FAST_WRITE))
  93                         FD_SET (i, &wfdset);
  94                 FD_SET (i, &errfdset);
  95         }
  96
  97         /* One second wait */
  98         tval.tv_sec = 1;
  99         tval.tv_usec = 0;
 100
 101         sresult = select(FD_SETSIZE, &rfdset, &wfdset, &errfdset, &tval);
 102
 103         /* Nothing to process this time around */
 104         if (sresult < 1)
 105                 return 0;
 106
 107         for (int i = 0; i < FD_SETSIZE; i++)
 108         {
 109                 EventHandler* ev = ref[i];
 110                 if (ev)
 111                 {
 112                         if (FD_ISSET (i, &errfdset))
 113                         {
 114                                 ErrorEvents++;
 115                                 if (getsockopt(i, SOL_SOCKET, SO_ERROR, (char*)&errcode, &codesize) < 0)
 116                                         errcode = errno;
 117
 118                                 ev->HandleEvent(EVENT_ERROR, errcode);
 119                                 continue;
 120                         }
 121                         else
 122                         {
 123                                 /* NOTE: This is a pair of seperate if statements as the socket
 124                                  * may be in both read and writeable state at the same time.
 125                                  * If an error event occurs above it is not worth processing the
 126                                  * read and write states even if set.
 127                                  */
 128                                 if (FD_ISSET (i, &rfdset))
 129                                 {
 130                                         ReadEvents++;
 131                                         SetEventMask(eh, eh->GetEventMask() & ~FD_READ_WILL_BLOCK);
 132                                         ev->HandleEvent(EVENT_READ);
 133                                 }
 134                                 if (FD_ISSET (i, &wfdset))
 135                                 {
 136                                         WriteEvents++;
 137                                         SetEventMask(eh, eh->GetEventMask() & ~FD_WRITE_WILL_BLOCK);
 138                                         ev->HandleEvent(EVENT_WRITE);
 139                                 }
 140                         }
 141                 }
 142         }
 143
 144         return sresult;
 145 }
 146
 147 std::string SelectEngine::GetName()
 148 {
 149         return "select";
 150 }