src/socketengines/socketengine_select.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2014 Adam <Adam@anope.org>
   5  *   Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
   6  *   Copyright (C) 2007-2008 Craig Edwards <craigedwards@brainbox.cc>
   7  *
   8  * This file is part of InspIRCd.  InspIRCd is free software: you can
   9  * redistribute it and/or modify it under the terms of the GNU General Public
  10  * License as published by the Free Software Foundation, version 2.
  11  *
  12  * This program is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  14  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  15  * details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21
  22 #include "inspircd.h"
  23
  24 #ifndef _WIN32
  25 #include <sys/select.h>
  26 #endif // _WIN32
  27
  28 /** A specialisation of the SocketEngine class, designed to use traditional select().
  29  */
  30 namespace
  31 {
  32         fd_set ReadSet, WriteSet, ErrSet;
  33         int MaxFD = 0;
  34 }
  35
  36 void SocketEngine::Init()
  37 {
  38         MAX_DESCRIPTORS = FD_SETSIZE;
  39
  40         FD_ZERO(&ReadSet);
  41         FD_ZERO(&WriteSet);
  42         FD_ZERO(&ErrSet);
  43 }
  44
  45 void SocketEngine::Deinit()
  46 {
  47 }
  48
  49 void SocketEngine::RecoverFromFork()
  50 {
  51 }
  52
  53 bool SocketEngine::AddFd(EventHandler* eh, int event_mask)
  54 {
  55         int fd = eh->GetFd();
  56         if ((fd < 0) || (fd > GetMaxFds() - 1))
  57                 return false;
  58
  59         if (!SocketEngine::AddFdRef(eh))
  60                 return false;
  61
  62         eh->SetEventMask(event_mask);
  63         OnSetEvent(eh, 0, event_mask);
  64         FD_SET(fd, &ErrSet);
  65         if (fd > MaxFD)
  66                 MaxFD = fd;
  67
  68         ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "New file descriptor: %d", fd);
  69         return true;
  70 }
  71
  72 void SocketEngine::DelFd(EventHandler* eh)
  73 {
  74         int fd = eh->GetFd();
  75
  76         if ((fd < 0) || (fd > GetMaxFds() - 1))
  77                 return;
  78
  79         SocketEngine::DelFdRef(eh);
  80
  81         FD_CLR(fd, &ReadSet);
  82         FD_CLR(fd, &WriteSet);
  83         FD_CLR(fd, &ErrSet);
  84         if (fd == MaxFD)
  85                 --MaxFD;
  86
  87         ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Remove file descriptor: %d", fd);
  88 }
  89
  90 void SocketEngine::OnSetEvent(EventHandler* eh, int old_mask, int new_mask)
  91 {
  92         int fd = eh->GetFd();
  93         int diff = old_mask ^ new_mask;
  94
  95         if (diff & (FD_WANT_POLL_READ | FD_WANT_FAST_READ))
  96         {
  97                 if (new_mask & (FD_WANT_POLL_READ | FD_WANT_FAST_READ))
  98                         FD_SET(fd, &ReadSet);
  99                 else
 100                         FD_CLR(fd, &ReadSet);
 101         }
 102         if (diff & (FD_WANT_POLL_WRITE | FD_WANT_FAST_WRITE | FD_WANT_SINGLE_WRITE))
 103         {
 104                 if (new_mask & (FD_WANT_POLL_WRITE | FD_WANT_FAST_WRITE | FD_WANT_SINGLE_WRITE))
 105                         FD_SET(fd, &WriteSet);
 106                 else
 107                         FD_CLR(fd, &WriteSet);
 108         }
 109 }
 110
 111 int SocketEngine::DispatchEvents()
 112 {
 113         timeval tval;
 114         tval.tv_sec = 1;
 115         tval.tv_usec = 0;
 116
 117         fd_set rfdset = ReadSet, wfdset = WriteSet, errfdset = ErrSet;
 118
 119         int sresult = select(MaxFD + 1, &rfdset, &wfdset, &errfdset, &tval);
 120         ServerInstance->UpdateTime();
 121
 122         for (int i = 0, j = sresult; i <= MaxFD && j > 0; i++)
 123         {
 124                 int has_read = FD_ISSET(i, &rfdset), has_write = FD_ISSET(i, &wfdset), has_error = FD_ISSET(i, &errfdset);
 125
 126                 if (!(has_read || has_write || has_error))
 127                         continue;
 128
 129                 --j;
 130
 131                 EventHandler* ev = GetRef(i);
 132                 if (!ev)
 133                         continue;
 134
 135                 if (has_error)
 136                 {
 137                         stats.ErrorEvents++;
 138
 139                         socklen_t codesize = sizeof(int);
 140                         int errcode = 0;
 141                         if (getsockopt(i, SOL_SOCKET, SO_ERROR, (char*)&errcode, &codesize) < 0)
 142                                 errcode = errno;
 143
 144                         ev->HandleEvent(EVENT_ERROR, errcode);
 145                         continue;
 146                 }
 147
 148                 if (has_read)
 149                 {
 150                         stats.ReadEvents++;
 151                         ev->SetEventMask(ev->GetEventMask() & ~FD_READ_WILL_BLOCK);
 152                         ev->HandleEvent(EVENT_READ);
 153                         if (ev != GetRef(i))
 154                                 continue;
 155                 }
 156
 157                 if (has_write)
 158                 {
 159                         stats.WriteEvents++;
 160                         int newmask = (ev->GetEventMask() & ~(FD_WRITE_WILL_BLOCK | FD_WANT_SINGLE_WRITE));
 161                         SocketEngine::OnSetEvent(ev, ev->GetEventMask(), newmask);
 162                         ev->SetEventMask(newmask);
 163                         ev->HandleEvent(EVENT_WRITE);
 164                 }
 165         }
 166
 167         return sresult;
 168 }