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);
79 void io_set(event_loop_t *loop, io_t *io, int flags) {
85 FD_SET(io->fd, &loop->readfds);
87 FD_CLR(io->fd, &loop->readfds);
90 if(flags & IO_WRITE) {
91 FD_SET(io->fd, &loop->writefds);
93 FD_CLR(io->fd, &loop->writefds);
97 void io_del(event_loop_t *loop, io_t *io) {
100 loop->deletion = true;
104 splay_unlink_node(&loop->ios, &io->node);
108 void timeout_add(event_loop_t *loop, timeout_t *timeout, timeout_cb_t cb, void *data, struct timeval *tv) {
110 timeout->data = data;
111 timeout->node.data = timeout;
113 timeout_set(loop, timeout, tv);
116 void timeout_set(event_loop_t *loop, timeout_t *timeout, struct timeval *tv) {
119 if(timerisset(&timeout->tv)) {
120 splay_unlink_node(&loop->timeouts, &timeout->node);
123 if(!loop->now.tv_sec) {
124 gettimeofday(&loop->now, NULL);
127 timeradd(&loop->now, tv, &timeout->tv);
129 if(!splay_insert_node(&loop->timeouts, &timeout->node)) {
133 loop->deletion = true;
136 static void timeout_disable(event_loop_t *loop, timeout_t *timeout) {
137 splay_unlink_node(&loop->timeouts, &timeout->node);
138 timeout->tv = (struct timeval) {
143 void timeout_del(event_loop_t *loop, timeout_t *timeout) {
148 if(timerisset(&timeout->tv)) {
149 timeout_disable(loop, timeout);
153 loop->deletion = true;
156 static int signal_compare(const signal_t *a, const signal_t *b) {
157 return (int)a->signum - (int)b->signum;
160 static void signalio_handler(event_loop_t *loop, void *data, int flags) {
163 unsigned char signum;
165 if(read(loop->pipefd[0], &signum, 1) != 1) {
169 signal_t *sig = splay_search(&loop->signals, &(signal_t) {
175 sig->cb(loop, sig->data);
179 static void pipe_init(event_loop_t *loop) {
180 int result = pipe(loop->pipefd);
184 io_add(loop, &loop->signalio, signalio_handler, NULL, loop->pipefd[0], IO_READ);
188 static void pipe_exit(event_loop_t *loop) {
189 io_del(loop, &loop->signalio);
191 close(loop->pipefd[0]);
192 close(loop->pipefd[1]);
194 loop->pipefd[0] = -1;
195 loop->pipefd[1] = -1;
198 void signal_trigger(event_loop_t *loop, signal_t *sig) {
203 uint8_t signum = sig->signum;
205 write(loop->pipefd[1], &signum, 1);
209 void signal_add(event_loop_t *loop, signal_t *sig, signal_cb_t cb, void *data, uint8_t signum) {
214 sig->signum = signum;
216 sig->node.data = sig;
218 if(loop->pipefd[0] == -1) {
222 if(!splay_insert_node(&loop->signals, &sig->node)) {
227 void signal_del(event_loop_t *loop, signal_t *sig) {
230 loop->deletion = true;
232 splay_unlink_node(&loop->signals, &sig->node);
235 if(!loop->signals.count && loop->pipefd[0] != -1) {
240 void idle_set(event_loop_t *loop, idle_cb_t cb, void *data) {
242 loop->idle_data = data;
245 bool event_loop_run(event_loop_t *loop, pthread_mutex_t *mutex) {
251 while(loop->running) {
252 gettimeofday(&loop->now, NULL);
253 struct timeval diff, it, *tv = NULL;
255 while(loop->timeouts.head) {
256 timeout_t *timeout = loop->timeouts.head->data;
257 timersub(&timeout->tv, &loop->now, &diff);
259 if(diff.tv_sec < 0) {
260 timeout_disable(loop, timeout);
261 timeout->cb(loop, timeout->data);
269 it = loop->idle_cb(loop, loop->idle_data);
271 if(it.tv_sec >= 0 && (!tv || timercmp(&it, tv, <))) {
276 memcpy(&readable, &loop->readfds, sizeof(readable));
277 memcpy(&writable, &loop->writefds, sizeof(writable));
282 io_t *last = loop->ios.tail->data;
286 // release mesh mutex during select
287 pthread_mutex_unlock(mutex);
289 int n = select(fds, &readable, &writable, NULL, tv);
291 pthread_mutex_lock(mutex);
293 gettimeofday(&loop->now, NULL);
296 if(sockwouldblock(errno)) {
307 // Normally, splay_each allows the current node to be deleted. However,
308 // it can be that one io callback triggers the deletion of another io,
309 // so we have to detect this and break the loop.
311 loop->deletion = false;
313 for splay_each(io_t, io, &loop->ios) {
314 if(FD_ISSET(io->fd, &writable) && io->cb) {
315 io->cb(loop, io->data, IO_WRITE);
322 if(FD_ISSET(io->fd, &readable) && io->cb) {
323 io->cb(loop, io->data, IO_READ);
335 void event_flush_output(event_loop_t *loop) {
336 for splay_each(io_t, io, &loop->ios)
337 if(FD_ISSET(io->fd, &loop->writefds)) {
338 io->cb(loop, io->data, IO_WRITE);
342 void event_loop_start(event_loop_t *loop) {
343 loop->running = true;
346 void event_loop_stop(event_loop_t *loop) {
347 loop->running = false;
350 void event_loop_init(event_loop_t *loop) {
351 loop->ios.compare = (splay_compare_t)io_compare;
352 loop->timeouts.compare = (splay_compare_t)timeout_compare;
353 loop->signals.compare = (splay_compare_t)signal_compare;
354 loop->pipefd[0] = -1;
355 loop->pipefd[1] = -1;
356 gettimeofday(&loop->now, NULL);
359 void event_loop_exit(event_loop_t *loop) {
360 assert(!loop->ios.count);
361 assert(!loop->timeouts.count);
362 assert(!loop->signals.count);
364 for splay_each(io_t, io, &loop->ios) {
365 splay_unlink_node(&loop->ios, node);
368 for splay_each(timeout_t, timeout, &loop->timeouts) {
369 splay_unlink_node(&loop->timeouts, node);
372 for splay_each(signal_t, signal, &loop->signals) {
373 splay_unlink_node(&loop->signals, node);