1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
/*
* InspIRCd -- Internet Relay Chat Daemon
*
* Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
* Copyright (C) 2007-2008 Craig Edwards <craigedwards@brainbox.cc>
*
* This file is part of InspIRCd. InspIRCd is free software: you can
* redistribute it and/or modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "inspircd.h"
#include <sys/epoll.h>
#include <sys/resource.h>
/** A specialisation of the SocketEngine class, designed to use linux 2.6 epoll().
*/
namespace
{
int EngineHandle;
/** These are used by epoll() to hold socket events
*/
std::vector<struct epoll_event> events(16);
}
void SocketEngine::Init()
{
LookupMaxFds();
// 128 is not a maximum, just a hint at the eventual number of sockets that may be polled,
// and it is completely ignored by 2.6.8 and later kernels, except it must be larger than zero.
EngineHandle = epoll_create(128);
if (EngineHandle == -1)
InitError();
}
void SocketEngine::RecoverFromFork()
{
}
void SocketEngine::Deinit()
{
Close(EngineHandle);
}
static unsigned mask_to_epoll(int event_mask)
{
unsigned rv = 0;
if (event_mask & (FD_WANT_POLL_READ | FD_WANT_POLL_WRITE | FD_WANT_SINGLE_WRITE))
{
// we need to use standard polling on this FD
if (event_mask & (FD_WANT_POLL_READ | FD_WANT_FAST_READ))
rv |= EPOLLIN;
if (event_mask & (FD_WANT_POLL_WRITE | FD_WANT_FAST_WRITE | FD_WANT_SINGLE_WRITE))
rv |= EPOLLOUT;
}
else
{
// we can use edge-triggered polling on this FD
rv = EPOLLET;
if (event_mask & (FD_WANT_FAST_READ | FD_WANT_EDGE_READ))
rv |= EPOLLIN;
if (event_mask & (FD_WANT_FAST_WRITE | FD_WANT_EDGE_WRITE))
rv |= EPOLLOUT;
}
return rv;
}
bool SocketEngine::AddFd(EventHandler* eh, int event_mask)
{
int fd = eh->GetFd();
if (fd < 0)
{
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "AddFd out of range: (fd: %d)", fd);
return false;
}
if (!SocketEngine::AddFdRef(eh))
{
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Attempt to add duplicate fd: %d", fd);
return false;
}
struct epoll_event ev;
memset(&ev, 0, sizeof(ev));
ev.events = mask_to_epoll(event_mask);
ev.data.ptr = static_cast<void*>(eh);
int i = epoll_ctl(EngineHandle, EPOLL_CTL_ADD, fd, &ev);
if (i < 0)
{
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Error adding fd: %d to socketengine: %s", fd, strerror(errno));
return false;
}
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "New file descriptor: %d", fd);
eh->SetEventMask(event_mask);
ResizeDouble(events);
return true;
}
void SocketEngine::OnSetEvent(EventHandler* eh, int old_mask, int new_mask)
{
unsigned old_events = mask_to_epoll(old_mask);
unsigned new_events = mask_to_epoll(new_mask);
if (old_events != new_events)
{
// ok, we actually have something to tell the kernel about
struct epoll_event ev;
memset(&ev, 0, sizeof(ev));
ev.events = new_events;
ev.data.ptr = static_cast<void*>(eh);
epoll_ctl(EngineHandle, EPOLL_CTL_MOD, eh->GetFd(), &ev);
}
}
void SocketEngine::DelFd(EventHandler* eh)
{
int fd = eh->GetFd();
if (fd < 0)
{
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "DelFd out of range: (fd: %d)", fd);
return;
}
// Do not initialize epoll_event because for EPOLL_CTL_DEL operations the event is ignored and can be NULL.
// In kernel versions before 2.6.9, the EPOLL_CTL_DEL operation required a non-NULL pointer in event,
// even though this argument is ignored. Since Linux 2.6.9, event can be specified as NULL when using EPOLL_CTL_DEL.
struct epoll_event ev;
int i = epoll_ctl(EngineHandle, EPOLL_CTL_DEL, fd, &ev);
if (i < 0)
{
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "epoll_ctl can't remove socket: %s", strerror(errno));
}
SocketEngine::DelFdRef(eh);
ServerInstance->Logs->Log("SOCKET", LOG_DEBUG, "Remove file descriptor: %d", fd);
}
int SocketEngine::DispatchEvents()
{
int i = epoll_wait(EngineHandle, &events[0], events.size(), 1000);
ServerInstance->UpdateTime();
stats.TotalEvents += i;
for (int j = 0; j < i; j++)
{
// Copy these in case the vector gets resized and ev invalidated
const epoll_event ev = events[j];
EventHandler* const eh = static_cast<EventHandler*>(ev.data.ptr);
const int fd = eh->GetFd();
if (fd < 0)
continue;
if (ev.events & EPOLLHUP)
{
stats.ErrorEvents++;
eh->OnEventHandlerError(0);
continue;
}
if (ev.events & EPOLLERR)
{
stats.ErrorEvents++;
/* Get error number */
socklen_t codesize = sizeof(int);
int errcode;
if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &errcode, &codesize) < 0)
errcode = errno;
eh->OnEventHandlerError(errcode);
continue;
}
int mask = eh->GetEventMask();
if (ev.events & EPOLLIN)
mask &= ~FD_READ_WILL_BLOCK;
if (ev.events & EPOLLOUT)
{
mask &= ~FD_WRITE_WILL_BLOCK;
if (mask & FD_WANT_SINGLE_WRITE)
{
int nm = mask & ~FD_WANT_SINGLE_WRITE;
OnSetEvent(eh, mask, nm);
mask = nm;
}
}
eh->SetEventMask(mask);
if (ev.events & EPOLLIN)
{
eh->OnEventHandlerRead();
if (eh != GetRef(fd))
// whoa! we got deleted, better not give out the write event
continue;
}
if (ev.events & EPOLLOUT)
{
eh->OnEventHandlerWrite();
}
}
return i;
}
|
