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 #include "socketengine.h"
  24
  25 #ifndef _WIN32
  26 #include <sys/select.h>
  27 #endif // _WIN32
  28
  29 /** A specialisation of the SocketEngine class, designed to use traditional select().
  30  */
  31 namespace
  32 {
  33         fd_set ReadSet, WriteSet, ErrSet;
  34         int MaxFD = 0;
  35 }
  36
  37 void SocketEngine::Init()
  38 {
  39         MAX_DESCRIPTORS = FD_SETSIZE;
  40
  41         FD_ZERO(&ReadSet);
  42         FD_ZERO(&WriteSet);
  43         FD_ZERO(&ErrSet);
  44 }
  45
  46 void SocketEngine::Deinit()
  47 {
  48 }
  49
  50 void SocketEngine::RecoverFromFork()
  51 {
  52 }
  53
  54 bool SocketEngine::AddFd(EventHandler* eh, int event_mask)
  55 {
  56         int fd = eh->GetFd();
  57         if ((fd < 0) || (fd > GetMaxFds() - 1))
  58                 return false;
  59
  60         if (!SocketEngine::AddFdRef(eh))
  61                 return false;
  62
  63         eh->SetEventMask(event_mask);
  64         OnSetEvent(eh, 0, event_mask);
  65         FD_SET(fd, &ErrSet);
  66         if (fd > MaxFD)
  67                 MaxFD = fd;
  68
  69         ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "New file descriptor: %d", fd);
  70         return true;
  71 }
  72
  73 void SocketEngine::DelFd(EventHandler* eh)
  74 {
  75         int fd = eh->GetFd();
  76
  77         if ((fd < 0) || (fd > GetMaxFds() - 1))
  78                 return;
  79
  80         SocketEngine::DelFdRef(eh);
  81
  82         FD_CLR(fd, &ReadSet);
  83         FD_CLR(fd, &WriteSet);
  84         FD_CLR(fd, &ErrSet);
  85         if (fd == MaxFD)
  86                 --MaxFD;
  87
  88         ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Remove file descriptor: %d", fd);
  89 }
  90
  91 void SocketEngine::OnSetEvent(EventHandler* eh, int old_mask, int new_mask)
  92 {
  93         int fd = eh->GetFd();
  94         int diff = old_mask ^ new_mask;
  95
  96         if (diff & (FD_WANT_POLL_READ | FD_WANT_FAST_READ))
  97         {
  98                 if (new_mask & (FD_WANT_POLL_READ | FD_WANT_FAST_READ))
  99                         FD_SET(fd, &ReadSet);
 100                 else
 101                         FD_CLR(fd, &ReadSet);
 102         }
 103         if (diff & (FD_WANT_POLL_WRITE | FD_WANT_FAST_WRITE | FD_WANT_SINGLE_WRITE))
 104         {
 105                 if (new_mask & (FD_WANT_POLL_WRITE | FD_WANT_FAST_WRITE | FD_WANT_SINGLE_WRITE))
 106                         FD_SET(fd, &WriteSet);
 107                 else
 108                         FD_CLR(fd, &WriteSet);
 109         }
 110 }
 111
 112 int SocketEngine::DispatchEvents()
 113 {
 114         static timeval tval = { 1, 0 };
 115
 116         fd_set rfdset = ReadSet, wfdset = WriteSet, errfdset = ErrSet;
 117
 118         int sresult = select(MaxFD + 1, &rfdset, &wfdset, &errfdset, &tval);
 119         ServerInstance->UpdateTime();
 120
 121         for (int i = 0, j = sresult; i <= MaxFD && j > 0; i++)
 122         {
 123                 int has_read = FD_ISSET(i, &rfdset), has_write = FD_ISSET(i, &wfdset), has_error = FD_ISSET(i, &errfdset);
 124
 125                 if (!(has_read || has_write || has_error))
 126                         continue;
 127
 128                 --j;
 129
 130                 EventHandler* ev = GetRef(i);
 131                 if (!ev)
 132                         continue;
 133
 134                 if (has_error)
 135                 {
 136                         stats.ErrorEvents++;
 137
 138                         socklen_t codesize = sizeof(int);
 139                         int errcode = 0;
 140                         if (getsockopt(i, SOL_SOCKET, SO_ERROR, (char*)&errcode, &codesize) < 0)
 141                                 errcode = errno;
 142
 143                         ev->HandleEvent(EVENT_ERROR, errcode);
 144                         continue;
 145                 }
 146
 147                 if (has_read)
 148                 {
 149                         stats.ReadEvents++;
 150                         ev->SetEventMask(ev->GetEventMask() & ~FD_READ_WILL_BLOCK);
 151                         ev->HandleEvent(EVENT_READ);
 152                         if (ev != GetRef(i))
 153                                 continue;
 154                 }
 155
 156                 if (has_write)
 157                 {
 158                         stats.WriteEvents++;
 159                         int newmask = (ev->GetEventMask() & ~(FD_WRITE_WILL_BLOCK | FD_WANT_SINGLE_WRITE));
 160                         SocketEngine::OnSetEvent(ev, ev->GetEventMask(), newmask);
 161                         ev->SetEventMask(newmask);
 162                         ev->HandleEvent(EVENT_WRITE);
 163                 }
 164         }
 165
 166         return sresult;
 167 }