2 * InspIRCd -- Internet Relay Chat Daemon
4 * Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
5 * Copyright (C) 2007-2008 Craig Edwards <craigedwards@brainbox.cc>
7 * This file is part of InspIRCd. InspIRCd is free software: you can
8 * redistribute it and/or modify it under the terms of the GNU General Public
9 * License as published by the Free Software Foundation, version 2.
11 * This program is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
13 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
22 #include "exitcodes.h"
24 #include <sys/epoll.h>
28 /** A specialisation of the SocketEngine class, designed to use linux 2.6 epoll().
34 /** These are used by epoll() to hold socket events
36 std::vector<struct epoll_event> events(1);
39 void SocketEngine::Init()
41 // MAX_DESCRIPTORS is mainly used for display purposes, no problem if ulimit() fails and returns a negative number
42 MAX_DESCRIPTORS = ulimit(4, 0);
44 // 128 is not a maximum, just a hint at the eventual number of sockets that may be polled,
45 // and it is completely ignored by 2.6.8 and later kernels, except it must be larger than zero.
46 EngineHandle = epoll_create(128);
48 if (EngineHandle == -1)
50 ServerInstance->Logs->Log("SOCKET", LOG_DEFAULT, "ERROR: Could not initialize socket engine: %s", strerror(errno));
51 ServerInstance->Logs->Log("SOCKET", LOG_DEFAULT, "ERROR: Your kernel probably does not have the proper features. This is a fatal error, exiting now.");
52 std::cout << "ERROR: Could not initialize epoll socket engine: " << strerror(errno) << std::endl;
53 std::cout << "ERROR: Your kernel probably does not have the proper features. This is a fatal error, exiting now." << std::endl;
54 ServerInstance->QuickExit(EXIT_STATUS_SOCKETENGINE);
58 void SocketEngine::RecoverFromFork()
62 void SocketEngine::Deinit()
67 static unsigned mask_to_epoll(int event_mask)
70 if (event_mask & (FD_WANT_POLL_READ | FD_WANT_POLL_WRITE | FD_WANT_SINGLE_WRITE))
72 // we need to use standard polling on this FD
73 if (event_mask & (FD_WANT_POLL_READ | FD_WANT_FAST_READ))
75 if (event_mask & (FD_WANT_POLL_WRITE | FD_WANT_FAST_WRITE | FD_WANT_SINGLE_WRITE))
80 // we can use edge-triggered polling on this FD
82 if (event_mask & (FD_WANT_FAST_READ | FD_WANT_EDGE_READ))
84 if (event_mask & (FD_WANT_FAST_WRITE | FD_WANT_EDGE_WRITE))
90 bool SocketEngine::AddFd(EventHandler* eh, int event_mask)
95 ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "AddFd out of range: (fd: %d)", fd);
99 if (!SocketEngine::AddFdRef(eh))
101 ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Attempt to add duplicate fd: %d", fd);
105 struct epoll_event ev;
106 memset(&ev, 0, sizeof(ev));
107 ev.events = mask_to_epoll(event_mask);
108 ev.data.ptr = static_cast<void*>(eh);
109 int i = epoll_ctl(EngineHandle, EPOLL_CTL_ADD, fd, &ev);
112 ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Error adding fd: %d to socketengine: %s", fd, strerror(errno));
116 ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "New file descriptor: %d", fd);
118 eh->SetEventMask(event_mask);
119 ResizeDouble(events);
124 void SocketEngine::OnSetEvent(EventHandler* eh, int old_mask, int new_mask)
126 unsigned old_events = mask_to_epoll(old_mask);
127 unsigned new_events = mask_to_epoll(new_mask);
128 if (old_events != new_events)
130 // ok, we actually have something to tell the kernel about
131 struct epoll_event ev;
132 memset(&ev, 0, sizeof(ev));
133 ev.events = new_events;
134 ev.data.ptr = static_cast<void*>(eh);
135 epoll_ctl(EngineHandle, EPOLL_CTL_MOD, eh->GetFd(), &ev);
139 void SocketEngine::DelFd(EventHandler* eh)
141 int fd = eh->GetFd();
144 ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "DelFd out of range: (fd: %d)", fd);
148 // Do not initialize epoll_event because for EPOLL_CTL_DEL operations the event is ignored and can be NULL.
149 // In kernel versions before 2.6.9, the EPOLL_CTL_DEL operation required a non-NULL pointer in event,
150 // even though this argument is ignored. Since Linux 2.6.9, event can be specified as NULL when using EPOLL_CTL_DEL.
151 struct epoll_event ev;
152 int i = epoll_ctl(EngineHandle, EPOLL_CTL_DEL, fd, &ev);
156 ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "epoll_ctl can't remove socket: %s", strerror(errno));
159 SocketEngine::DelFdRef(eh);
161 ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Remove file descriptor: %d", fd);
164 int SocketEngine::DispatchEvents()
166 int i = epoll_wait(EngineHandle, &events[0], events.size(), 1000);
167 ServerInstance->UpdateTime();
169 stats.TotalEvents += i;
171 for (int j = 0; j < i; j++)
173 // Copy these in case the vector gets resized and ev invalidated
174 const epoll_event ev = events[j];
176 EventHandler* const eh = static_cast<EventHandler*>(ev.data.ptr);
177 const int fd = eh->GetFd();
181 if (ev.events & EPOLLHUP)
184 eh->OnEventHandlerError(0);
188 if (ev.events & EPOLLERR)
191 /* Get error number */
192 socklen_t codesize = sizeof(int);
194 if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &errcode, &codesize) < 0)
196 eh->OnEventHandlerError(errcode);
200 int mask = eh->GetEventMask();
201 if (ev.events & EPOLLIN)
202 mask &= ~FD_READ_WILL_BLOCK;
203 if (ev.events & EPOLLOUT)
205 mask &= ~FD_WRITE_WILL_BLOCK;
206 if (mask & FD_WANT_SINGLE_WRITE)
208 int nm = mask & ~FD_WANT_SINGLE_WRITE;
209 OnSetEvent(eh, mask, nm);
213 eh->SetEventMask(mask);
214 if (ev.events & EPOLLIN)
217 eh->OnEventHandlerRead();
218 if (eh != GetRef(fd))
219 // whoa! we got deleted, better not give out the write event
222 if (ev.events & EPOLLOUT)
225 eh->OnEventHandlerWrite();