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) {
100 timeout->node.data = timeout;
102 timeout_set(loop, timeout, tv);
105 void timeout_set(event_loop_t *loop, timeout_t *timeout, struct timeval *tv) {
106 if(timerisset(&timeout->tv))
107 splay_unlink_node(&loop->timeouts, &timeout->node);
109 if(!loop->now.tv_sec)
110 gettimeofday(&loop->now, NULL);
112 timeradd(&loop->now, tv, &timeout->tv);
114 if(!splay_insert_node(&loop->timeouts, &timeout->node))
118 void timeout_del(event_loop_t *loop, timeout_t *timeout) {
122 loop->deletion = true;
124 splay_unlink_node(&loop->timeouts, &timeout->node);
126 timeout->tv = (struct timeval) {
131 static int signal_compare(const signal_t *a, const signal_t *b) {
132 return (int)a->signum - (int)b->signum;
135 static void signalio_handler(event_loop_t *loop, void *data, int flags) {
136 unsigned char signum;
137 if(read(loop->pipefd[0], &signum, 1) != 1)
140 signal_t *sig = splay_search(&loop->signals, &((signal_t) {
144 sig->cb(loop, sig->data);
147 static void pipe_init(event_loop_t *loop) {
148 if(!pipe(loop->pipefd))
149 io_add(loop, &loop->signalio, signalio_handler, NULL, loop->pipefd[0], IO_READ);
152 void signal_trigger(event_loop_t *loop, signal_t *sig) {
154 uint8_t signum = sig->signum;
155 write(loop->pipefd[1], &signum, 1);
160 void signal_add(event_loop_t *loop, signal_t *sig, signal_cb_t cb, void *data, uint8_t signum) {
166 sig->signum = signum;
167 sig->node.data = sig;
169 if(loop->pipefd[0] == -1)
172 if(!splay_insert_node(&loop->signals, &sig->node))
176 void signal_del(event_loop_t *loop, signal_t *sig) {
180 loop->deletion = true;
182 splay_unlink_node(&loop->signals, &sig->node);
186 void idle_set(event_loop_t *loop, idle_cb_t cb, void *data) {
188 loop->idle_data = data;
191 bool event_loop_run(event_loop_t *loop, pthread_mutex_t *mutex) {
195 while(loop->running) {
196 gettimeofday(&loop->now, NULL);
197 struct timeval diff, it, *tv = NULL;
199 while(loop->timeouts.head) {
200 timeout_t *timeout = loop->timeouts.head->data;
201 timersub(&timeout->tv, &loop->now, &diff);
203 if(diff.tv_sec < 0) {
204 timeout->cb(loop, timeout->data);
205 if(timercmp(&timeout->tv, &loop->now, <))
206 timeout_del(loop, timeout);
214 it = loop->idle_cb(loop, loop->idle_data);
215 if(it.tv_sec >= 0 && (!tv || timercmp(&it, tv, <)))
219 memcpy(&readable, &loop->readfds, sizeof(readable));
220 memcpy(&writable, &loop->writefds, sizeof(writable));
225 io_t *last = loop->ios.tail->data;
229 // release mesh mutex during select
231 pthread_mutex_unlock(mutex);
232 int n = select(fds, &readable, &writable, NULL, tv);
234 pthread_mutex_lock(mutex);
237 if(sockwouldblock(errno))
246 // Normally, splay_each allows the current node to be deleted. However,
247 // it can be that one io callback triggers the deletion of another io,
248 // so we have to detect this and break the loop.
250 loop->deletion = false;
252 for splay_each(io_t, io, &loop->ios) {
253 if(FD_ISSET(io->fd, &writable) && io->cb)
254 io->cb(loop, io->data, IO_WRITE);
257 if(FD_ISSET(io->fd, &readable) && io->cb)
258 io->cb(loop, io->data, IO_READ);
267 void event_flush_output(event_loop_t *loop) {
268 for splay_each(io_t, io, &loop->ios)
269 if(FD_ISSET(io->fd, &loop->writefds))
270 io->cb(loop, io->data, IO_WRITE);
273 void event_loop_start(event_loop_t *loop) {
274 loop->running = true;
277 void event_loop_stop(event_loop_t *loop) {
278 loop->running = false;
281 void event_loop_init(event_loop_t *loop) {
282 loop->ios.compare = (splay_compare_t)io_compare;
283 loop->timeouts.compare = (splay_compare_t)timeout_compare;
284 loop->signals.compare = (splay_compare_t)signal_compare;
285 loop->pipefd[0] = -1;
286 loop->pipefd[1] = -1;
287 gettimeofday(&loop->now, NULL);
290 void event_loop_exit(event_loop_t *loop) {
291 for splay_each(io_t, io, &loop->ios)
292 splay_unlink_node(&loop->ios, node);
293 for splay_each(timeout_t, timeout, &loop->timeouts)
294 splay_unlink_node(&loop->timeouts, node);
295 for splay_each(signal_t, signal, &loop->signals)
296 splay_unlink_node(&loop->signals, node);