2 event.c -- I/O, timeout and signal event handling
3 Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License along
16 with this program; if not, write to the Free Software Foundation, Inc.,
17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
25 #include "splay_tree.h"
29 static int io_compare(const io_t *a, const io_t *b) {
33 static int timeout_compare(const timeout_t *a, const timeout_t *b) {
35 timersub(&a->tv, &b->tv, &diff);
51 void io_add(event_loop_t *loop, io_t *io, io_cb_t cb, void *data, int fd, int flags) {
60 io_set(loop, io, flags);
62 if(!splay_insert_node(&loop->ios, &io->node))
66 void io_set(event_loop_t *loop, io_t *io, int flags) {
70 FD_SET(io->fd, &loop->readfds);
72 FD_CLR(io->fd, &loop->readfds);
75 FD_SET(io->fd, &loop->writefds);
77 FD_CLR(io->fd, &loop->writefds);
80 void io_del(event_loop_t *loop, io_t *io) {
84 loop->deletion = true;
88 splay_unlink_node(&loop->ios, &io->node);
92 void timeout_add(event_loop_t *loop, timeout_t *timeout, timeout_cb_t cb, void *data, struct timeval *tv) {
94 timeout->tv = (struct timeval){0, 0};
98 timeout->node.data = timeout;
100 timeout_set(loop, timeout, tv);
103 void timeout_set(event_loop_t *loop, timeout_t *timeout, struct timeval *tv) {
104 if(timerisset(&timeout->tv))
105 splay_unlink_node(&loop->timeouts, &timeout->node);
107 if(!loop->now.tv_sec)
108 gettimeofday(&loop->now, NULL);
110 timeradd(&loop->now, tv, &timeout->tv);
112 if(!splay_insert_node(&loop->timeouts, &timeout->node))
116 void timeout_del(event_loop_t *loop, timeout_t *timeout) {
120 loop->deletion = true;
122 splay_unlink_node(&loop->timeouts, &timeout->node);
124 timeout->tv = (struct timeval){0, 0};
127 static int signal_compare(const signal_t *a, const signal_t *b) {
128 return (int)a->signum - (int)b->signum;
131 static void signalio_handler(event_loop_t *loop, void *data, int flags) {
132 unsigned char signum;
133 if(read(loop->pipefd[0], &signum, 1) != 1)
136 signal_t *sig = splay_search(&loop->signals, &((signal_t){.signum = signum}));
138 sig->cb(loop, sig->data);
141 static void pipe_init(event_loop_t *loop) {
142 if(!pipe(loop->pipefd))
143 io_add(loop, &loop->signalio, signalio_handler, NULL, loop->pipefd[0], IO_READ);
146 void signal_trigger(event_loop_t *loop, signal_t *sig) {
148 uint8_t signum = sig->signum;
149 write(loop->pipefd[1], &signum, 1);
154 void signal_add(event_loop_t *loop, signal_t *sig, signal_cb_t cb, void *data, uint8_t signum) {
160 sig->signum = signum;
161 sig->node.data = sig;
163 if(loop->pipefd[0] == -1)
166 if(!splay_insert_node(&loop->signals, &sig->node))
170 void signal_del(event_loop_t *loop, signal_t *sig) {
174 loop->deletion = true;
176 splay_unlink_node(&loop->signals, &sig->node);
180 void idle_set(event_loop_t *loop, idle_cb_t cb, void *data) {
182 loop->idle_data = data;
185 bool event_loop_run(event_loop_t *loop, pthread_mutex_t *mutex) {
189 while(loop->running) {
190 gettimeofday(&loop->now, NULL);
191 struct timeval diff, it, *tv = NULL;
193 while(loop->timeouts.head) {
194 timeout_t *timeout = loop->timeouts.head->data;
195 timersub(&timeout->tv, &loop->now, &diff);
197 if(diff.tv_sec < 0) {
198 timeout->cb(loop, timeout->data);
199 if(timercmp(&timeout->tv, &loop->now, <))
200 timeout_del(loop, timeout);
208 it = loop->idle_cb(loop, loop->idle_data);
209 if(it.tv_sec >= 0 && (!tv || timercmp(&it, tv, <)))
213 memcpy(&readable, &loop->readfds, sizeof readable);
214 memcpy(&writable, &loop->writefds, sizeof writable);
219 io_t *last = loop->ios.tail->data;
223 // release mesh mutex during select
225 pthread_mutex_unlock(mutex);
226 int n = select(fds, &readable, &writable, NULL, tv);
228 pthread_mutex_lock(mutex);
231 if(sockwouldblock(errno))
240 // Normally, splay_each allows the current node to be deleted. However,
241 // it can be that one io callback triggers the deletion of another io,
242 // so we have to detect this and break the loop.
244 loop->deletion = false;
246 for splay_each(io_t, io, &loop->ios) {
247 if(FD_ISSET(io->fd, &writable) && io->cb)
248 io->cb(loop, io->data, IO_WRITE);
251 if(FD_ISSET(io->fd, &readable) && io->cb)
252 io->cb(loop, io->data, IO_READ);
261 void event_flush_output(event_loop_t *loop) {
262 for splay_each(io_t, io, &loop->ios)
263 if(FD_ISSET(io->fd, &loop->writefds))
264 io->cb(loop, io->data, IO_WRITE);
267 void event_loop_start(event_loop_t *loop) {
268 loop->running = true;
271 void event_loop_stop(event_loop_t *loop) {
272 loop->running = false;
275 void event_loop_init(event_loop_t *loop) {
276 loop->ios.compare = (splay_compare_t)io_compare;
277 loop->timeouts.compare = (splay_compare_t)timeout_compare;
278 loop->signals.compare = (splay_compare_t)signal_compare;
279 loop->pipefd[0] = -1;
280 loop->pipefd[1] = -1;
281 gettimeofday(&loop->now, NULL);
284 void event_loop_exit(event_loop_t *loop) {
285 for splay_each(io_t, io, &loop->ios)
286 splay_unlink_node(&loop->ios, node);
287 for splay_each(timeout_t, timeout, &loop->timeouts)
288 splay_unlink_node(&loop->timeouts, node);
289 for splay_each(signal_t, signal, &loop->signals)
290 splay_unlink_node(&loop->signals, node);