1/*
2 Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
3
4 This file is part of libzmq, the ZeroMQ core engine in C++.
5
6 libzmq is free software; you can redistribute it and/or modify it under
7 the terms of the GNU Lesser General Public License (LGPL) as published
8 by the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 As a special exception, the Contributors give you permission to link
12 this library with independent modules to produce an executable,
13 regardless of the license terms of these independent modules, and to
14 copy and distribute the resulting executable under terms of your choice,
15 provided that you also meet, for each linked independent module, the
16 terms and conditions of the license of that module. An independent
17 module is a module which is not derived from or based on this library.
18 If you modify this library, you must extend this exception to your
19 version of the library.
20
21 libzmq is distributed in the hope that it will be useful, but WITHOUT
22 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
23 FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
24 License for more details.
25
26 You should have received a copy of the GNU Lesser General Public License
27 along with this program. If not, see <http://www.gnu.org/licenses/>.
28*/
29
30#include "precompiled.hpp"
31#include "devpoll.hpp"
32#if defined ZMQ_IOTHREAD_POLLER_USE_DEVPOLL
33
34#include <sys/devpoll.h>
35#include <sys/time.h>
36#include <sys/types.h>
37#include <sys/stat.h>
38#include <sys/ioctl.h>
39#include <fcntl.h>
40#include <unistd.h>
41#include <limits.h>
42#include <algorithm>
43
44#include "devpoll.hpp"
45#include "err.hpp"
46#include "config.hpp"
47#include "i_poll_events.hpp"
48
49zmq::devpoll_t::devpoll_t (const zmq::thread_ctx_t &ctx_) :
50 worker_poller_base_t (ctx_)
51{
52 devpoll_fd = open ("/dev/poll", O_RDWR);
53 errno_assert (devpoll_fd != -1);
54}
55
56zmq::devpoll_t::~devpoll_t ()
57{
58 // Wait till the worker thread exits.
59 stop_worker ();
60
61 close (devpoll_fd);
62}
63
64void zmq::devpoll_t::devpoll_ctl (fd_t fd_, short events_)
65{
66 struct pollfd pfd = {fd_, events_, 0};
67 ssize_t rc = write (devpoll_fd, &pfd, sizeof pfd);
68 zmq_assert (rc == sizeof pfd);
69}
70
71zmq::devpoll_t::handle_t zmq::devpoll_t::add_fd (fd_t fd_,
72 i_poll_events *reactor_)
73{
74 check_thread ();
75 // If the file descriptor table is too small expand it.
76 fd_table_t::size_type sz = fd_table.size ();
77 if (sz <= (fd_table_t::size_type) fd_) {
78 fd_table.resize (fd_ + 1);
79 while (sz != (fd_table_t::size_type) (fd_ + 1)) {
80 fd_table[sz].valid = false;
81 ++sz;
82 }
83 }
84
85 zmq_assert (!fd_table[fd_].valid);
86
87 fd_table[fd_].events = 0;
88 fd_table[fd_].reactor = reactor_;
89 fd_table[fd_].valid = true;
90 fd_table[fd_].accepted = false;
91
92 devpoll_ctl (fd_, 0);
93 pending_list.push_back (fd_);
94
95 // Increase the load metric of the thread.
96 adjust_load (1);
97
98 return fd_;
99}
100
101void zmq::devpoll_t::rm_fd (handle_t handle_)
102{
103 check_thread ();
104 zmq_assert (fd_table[handle_].valid);
105
106 devpoll_ctl (handle_, POLLREMOVE);
107 fd_table[handle_].valid = false;
108
109 // Decrease the load metric of the thread.
110 adjust_load (-1);
111}
112
113void zmq::devpoll_t::set_pollin (handle_t handle_)
114{
115 check_thread ();
116 devpoll_ctl (handle_, POLLREMOVE);
117 fd_table[handle_].events |= POLLIN;
118 devpoll_ctl (handle_, fd_table[handle_].events);
119}
120
121void zmq::devpoll_t::reset_pollin (handle_t handle_)
122{
123 check_thread ();
124 devpoll_ctl (handle_, POLLREMOVE);
125 fd_table[handle_].events &= ~((short) POLLIN);
126 devpoll_ctl (handle_, fd_table[handle_].events);
127}
128
129void zmq::devpoll_t::set_pollout (handle_t handle_)
130{
131 check_thread ();
132 devpoll_ctl (handle_, POLLREMOVE);
133 fd_table[handle_].events |= POLLOUT;
134 devpoll_ctl (handle_, fd_table[handle_].events);
135}
136
137void zmq::devpoll_t::reset_pollout (handle_t handle_)
138{
139 check_thread ();
140 devpoll_ctl (handle_, POLLREMOVE);
141 fd_table[handle_].events &= ~((short) POLLOUT);
142 devpoll_ctl (handle_, fd_table[handle_].events);
143}
144
145void zmq::devpoll_t::stop ()
146{
147 check_thread ();
148}
149
150int zmq::devpoll_t::max_fds ()
151{
152 return -1;
153}
154
155void zmq::devpoll_t::loop ()
156{
157 while (true) {
158 struct pollfd ev_buf[max_io_events];
159 struct dvpoll poll_req;
160
161 for (pending_list_t::size_type i = 0; i < pending_list.size (); i++)
162 fd_table[pending_list[i]].accepted = true;
163 pending_list.clear ();
164
165 // Execute any due timers.
166 int timeout = (int) execute_timers ();
167
168 if (get_load () == 0) {
169 if (timeout == 0)
170 break;
171
172 // TODO sleep for timeout
173 continue;
174 }
175
176 // Wait for events.
177 // On Solaris, we can retrieve no more then (OPEN_MAX - 1) events.
178 poll_req.dp_fds = &ev_buf[0];
179#if defined ZMQ_HAVE_SOLARIS
180 poll_req.dp_nfds = std::min ((int) max_io_events, OPEN_MAX - 1);
181#else
182 poll_req.dp_nfds = max_io_events;
183#endif
184 poll_req.dp_timeout = timeout ? timeout : -1;
185 int n = ioctl (devpoll_fd, DP_POLL, &poll_req);
186 if (n == -1 && errno == EINTR)
187 continue;
188 errno_assert (n != -1);
189
190 for (int i = 0; i < n; i++) {
191 fd_entry_t *fd_ptr = &fd_table[ev_buf[i].fd];
192 if (!fd_ptr->valid || !fd_ptr->accepted)
193 continue;
194 if (ev_buf[i].revents & (POLLERR | POLLHUP))
195 fd_ptr->reactor->in_event ();
196 if (!fd_ptr->valid || !fd_ptr->accepted)
197 continue;
198 if (ev_buf[i].revents & POLLOUT)
199 fd_ptr->reactor->out_event ();
200 if (!fd_ptr->valid || !fd_ptr->accepted)
201 continue;
202 if (ev_buf[i].revents & POLLIN)
203 fd_ptr->reactor->in_event ();
204 }
205 }
206}
207
208#endif
209