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         MaxSetSize = 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
  57         if (fd < 0)
  58                 return false;
  59
  60         if (static_cast<size_t>(fd) >= GetMaxFds())
  61                 return false;
  62
  63         if (!SocketEngine::AddFdRef(eh))
  64                 return false;
  65
  66         eh->SetEventMask(event_mask);
  67         OnSetEvent(eh, 0, event_mask);
  68         FD_SET(fd, &ErrSet);
  69         if (fd > MaxFD)
  70                 MaxFD = fd;
  71
  72         ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "New file descriptor: %d", fd);
  73         return true;
  74 }
  75
  76 void SocketEngine::DelFd(EventHandler* eh)
  77 {
  78         int fd = eh->GetFd();
  79
  80         if (fd < 0)
  81                 return;
  82
  83         if (static_cast<size_t>(fd) >= GetMaxFds())
  84                 return;
  85
  86         SocketEngine::DelFdRef(eh);
  87
  88         FD_CLR(fd, &ReadSet);
  89         FD_CLR(fd, &WriteSet);
  90         FD_CLR(fd, &ErrSet);
  91         if (fd == MaxFD)
  92                 --MaxFD;
  93
  94         ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Remove file descriptor: %d", fd);
  95 }
  96
  97 void SocketEngine::OnSetEvent(EventHandler* eh, int old_mask, int new_mask)
  98 {
  99         int fd = eh->GetFd();
 100         int diff = old_mask ^ new_mask;
 101
 102         if (diff & (FD_WANT_POLL_READ | FD_WANT_FAST_READ))
 103         {
 104                 if (new_mask & (FD_WANT_POLL_READ | FD_WANT_FAST_READ))
 105                         FD_SET(fd, &ReadSet);
 106                 else
 107                         FD_CLR(fd, &ReadSet);
 108         }
 109         if (diff & (FD_WANT_POLL_WRITE | FD_WANT_FAST_WRITE | FD_WANT_SINGLE_WRITE))
 110         {
 111                 if (new_mask & (FD_WANT_POLL_WRITE | FD_WANT_FAST_WRITE | FD_WANT_SINGLE_WRITE))
 112                         FD_SET(fd, &WriteSet);
 113                 else
 114                         FD_CLR(fd, &WriteSet);
 115         }
 116 }
 117
 118 int SocketEngine::DispatchEvents()
 119 {
 120         timeval tval;
 121         tval.tv_sec = 1;
 122         tval.tv_usec = 0;
 123
 124         fd_set rfdset = ReadSet, wfdset = WriteSet, errfdset = ErrSet;
 125
 126         int sresult = select(MaxFD + 1, &rfdset, &wfdset, &errfdset, &tval);
 127         ServerInstance->UpdateTime();
 128
 129         for (int i = 0, j = sresult; i <= MaxFD && j > 0; i++)
 130         {
 131                 int has_read = FD_ISSET(i, &rfdset), has_write = FD_ISSET(i, &wfdset), has_error = FD_ISSET(i, &errfdset);
 132
 133                 if (!(has_read || has_write || has_error))
 134                         continue;
 135
 136                 --j;
 137
 138                 EventHandler* ev = GetRef(i);
 139                 if (!ev)
 140                         continue;
 141
 142                 if (has_error)
 143                 {
 144                         stats.ErrorEvents++;
 145
 146                         socklen_t codesize = sizeof(int);
 147                         int errcode = 0;
 148                         if (getsockopt(i, SOL_SOCKET, SO_ERROR, (char*)&errcode, &codesize) < 0)
 149                                 errcode = errno;
 150
 151                         ev->OnEventHandlerError(errcode);
 152                         continue;
 153                 }
 154
 155                 if (has_read)
 156                 {
 157                         ev->SetEventMask(ev->GetEventMask() & ~FD_READ_WILL_BLOCK);
 158                         ev->OnEventHandlerRead();
 159                         if (ev != GetRef(i))
 160                                 continue;
 161                 }
 162
 163                 if (has_write)
 164                 {
 165                         int newmask = (ev->GetEventMask() & ~(FD_WRITE_WILL_BLOCK | FD_WANT_SINGLE_WRITE));
 166                         SocketEngine::OnSetEvent(ev, ev->GetEventMask(), newmask);
 167                         ev->SetEventMask(newmask);
 168                         ev->OnEventHandlerWrite();
 169                 }
 170         }
 171
 172         return sresult;
 173 }