2 event.c -- I/O, timeout and signal event handling
3 Copyright (C) 2014-2017 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);
45 if(diff.tv_usec < 0) {
49 if(diff.tv_usec > 0) {
64 void io_add(event_loop_t *loop, io_t *io, io_cb_t cb, void *data, int fd, int flags) {
72 io_set(loop, io, flags);
74 splay_node_t *node = splay_insert_node(&loop->ios, &io->node);
78 void io_set(event_loop_t *loop, io_t *io, int flags) {
84 FD_SET(io->fd, &loop->readfds);
86 FD_CLR(io->fd, &loop->readfds);
89 if(flags & IO_WRITE) {
90 FD_SET(io->fd, &loop->writefds);
92 FD_CLR(io->fd, &loop->writefds);
96 void io_del(event_loop_t *loop, io_t *io) {
99 loop->deletion = true;
103 splay_unlink_node(&loop->ios, &io->node);
107 void timeout_add(event_loop_t *loop, timeout_t *timeout, timeout_cb_t cb, void *data, struct timeval *tv) {
109 timeout->data = data;
110 timeout->node.data = timeout;
112 timeout_set(loop, timeout, tv);
115 void timeout_set(event_loop_t *loop, timeout_t *timeout, struct timeval *tv) {
118 if(timerisset(&timeout->tv)) {
119 splay_unlink_node(&loop->timeouts, &timeout->node);
122 if(!loop->now.tv_sec) {
123 gettimeofday(&loop->now, NULL);
126 timeradd(&loop->now, tv, &timeout->tv);
128 if(!splay_insert_node(&loop->timeouts, &timeout->node)) {
132 loop->deletion = true;
135 static void timeout_disable(event_loop_t *loop, timeout_t *timeout) {
136 splay_unlink_node(&loop->timeouts, &timeout->node);
137 timeout->tv = (struct timeval) {
142 void timeout_del(event_loop_t *loop, timeout_t *timeout) {
147 if(timerisset(&timeout->tv)) {
148 timeout_disable(loop, timeout);
152 loop->deletion = true;
155 static int signal_compare(const signal_t *a, const signal_t *b) {
156 return (int)a->signum - (int)b->signum;
159 static void signalio_handler(event_loop_t *loop, void *data, int flags) {
162 unsigned char signum;
164 if(read(loop->pipefd[0], &signum, 1) != 1) {
168 signal_t *sig = splay_search(&loop->signals, &(signal_t) {
173 sig->cb(loop, sig->data);
177 static void pipe_init(event_loop_t *loop) {
178 int result = pipe(loop->pipefd);
182 io_add(loop, &loop->signalio, signalio_handler, NULL, loop->pipefd[0], IO_READ);
186 static void pipe_exit(event_loop_t *loop) {
187 io_del(loop, &loop->signalio);
189 close(loop->pipefd[0]);
190 close(loop->pipefd[1]);
192 loop->pipefd[0] = -1;
193 loop->pipefd[1] = -1;
196 void signal_trigger(event_loop_t *loop, signal_t *sig) {
197 uint8_t signum = sig->signum;
198 write(loop->pipefd[1], &signum, 1);
202 void signal_add(event_loop_t *loop, signal_t *sig, signal_cb_t cb, void *data, uint8_t signum) {
207 sig->signum = signum;
208 sig->node.data = sig;
210 if(loop->pipefd[0] == -1) {
214 if(!splay_insert_node(&loop->signals, &sig->node)) {
219 void signal_del(event_loop_t *loop, signal_t *sig) {
222 loop->deletion = true;
224 splay_unlink_node(&loop->signals, &sig->node);
227 if(!loop->signals.count && loop->pipefd[0] != -1) {
232 void idle_set(event_loop_t *loop, idle_cb_t cb, void *data) {
234 loop->idle_data = data;
237 bool event_loop_run(event_loop_t *loop, pthread_mutex_t *mutex) {
243 while(loop->running) {
244 gettimeofday(&loop->now, NULL);
245 struct timeval diff, it, *tv = NULL;
247 while(loop->timeouts.head) {
248 timeout_t *timeout = loop->timeouts.head->data;
249 timersub(&timeout->tv, &loop->now, &diff);
251 if(diff.tv_sec < 0) {
252 timeout_disable(loop, timeout);
253 timeout->cb(loop, timeout->data);
261 it = loop->idle_cb(loop, loop->idle_data);
263 if(it.tv_sec >= 0 && (!tv || timercmp(&it, tv, <))) {
268 memcpy(&readable, &loop->readfds, sizeof(readable));
269 memcpy(&writable, &loop->writefds, sizeof(writable));
274 io_t *last = loop->ios.tail->data;
278 // release mesh mutex during select
279 pthread_mutex_unlock(mutex);
281 int n = select(fds, &readable, &writable, NULL, tv);
283 pthread_mutex_lock(mutex);
285 gettimeofday(&loop->now, NULL);
288 if(sockwouldblock(errno)) {
299 // Normally, splay_each allows the current node to be deleted. However,
300 // it can be that one io callback triggers the deletion of another io,
301 // so we have to detect this and break the loop.
303 loop->deletion = false;
305 for splay_each(io_t, io, &loop->ios) {
306 if(FD_ISSET(io->fd, &writable) && io->cb) {
307 io->cb(loop, io->data, IO_WRITE);
314 if(FD_ISSET(io->fd, &readable) && io->cb) {
315 io->cb(loop, io->data, IO_READ);
327 void event_flush_output(event_loop_t *loop) {
328 for splay_each(io_t, io, &loop->ios)
329 if(FD_ISSET(io->fd, &loop->writefds)) {
330 io->cb(loop, io->data, IO_WRITE);
334 void event_loop_start(event_loop_t *loop) {
335 loop->running = true;
338 void event_loop_stop(event_loop_t *loop) {
339 loop->running = false;
342 void event_loop_init(event_loop_t *loop) {
343 loop->ios.compare = (splay_compare_t)io_compare;
344 loop->timeouts.compare = (splay_compare_t)timeout_compare;
345 loop->signals.compare = (splay_compare_t)signal_compare;
346 loop->pipefd[0] = -1;
347 loop->pipefd[1] = -1;
348 gettimeofday(&loop->now, NULL);
351 void event_loop_exit(event_loop_t *loop) {
352 assert(!loop->ios.count);
353 assert(!loop->timeouts.count);
354 assert(!loop->signals.count);
356 for splay_each(io_t, io, &loop->ios) {
357 splay_unlink_node(&loop->ios, node);
360 for splay_each(timeout_t, timeout, &loop->timeouts) {
361 splay_unlink_node(&loop->timeouts, node);
364 for splay_each(signal_t, signal, &loop->signals) {
365 splay_unlink_node(&loop->signals, node);