X-Git-Url: http://git.meshlink.io/?p=meshlink;a=blobdiff_plain;f=src%2Fevent.c;h=739ff35de5a595b76fee4f56ed43ca42b31e9e4c;hp=e4917589750a53e48cf8a563502b7563ed90a86a;hb=963c5055505f2fc117cd5efa06eaa02c9b2bf85d;hpb=158cbe99f972a1613b7d4d95abfe5fe48e019e67

diff --git a/src/event.c b/src/event.c
index e4917589..739ff35d 100644
--- a/src/event.c
+++ b/src/event.c
@@ -1,6 +1,6 @@
 /*
     event.c -- I/O, timeout and signal event handling
-    Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
+    Copyright (C) 2014-2017 Guus Sliepen <guus@meshlink.io>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -22,235 +22,385 @@
 #include "dropin.h"
 #include "event.h"
 #include "net.h"
+#include "splay_tree.h"
 #include "utils.h"
+#include "xalloc.h"
 
-struct timeval now;
+#ifndef EVENT_CLOCK
+#if defined(CLOCK_MONOTONIC_RAW) && defined(__x86_64__)
+#define EVENT_CLOCK CLOCK_MONOTONIC_RAW
+#else
+#define EVENT_CLOCK CLOCK_MONOTONIC
+#endif
+#endif
+
+static void timespec_add(const struct timespec *a, const struct timespec *b, struct timespec *r) {
+	r->tv_sec = a->tv_sec + b->tv_sec;
+	r->tv_nsec = a->tv_nsec + b->tv_nsec;
+
+	if(r->tv_nsec > 1000000000) {
+		r->tv_sec++, r->tv_nsec -= 1000000000;
+	}
+}
+
+static void timespec_sub(const struct timespec *a, const struct timespec *b, struct timespec *r) {
+	r->tv_sec = a->tv_sec - b->tv_sec;
+	r->tv_nsec = a->tv_nsec - b->tv_nsec;
+
+	if(r->tv_nsec < 0) {
+		r->tv_sec--, r->tv_nsec += 1000000000;
+	}
+}
+
+static bool timespec_lt(const struct timespec *a, const struct timespec *b) {
+	if(a->tv_sec == b->tv_sec) {
+		return a->tv_nsec < b->tv_nsec;
+	} else {
+		return a->tv_sec < b->tv_sec;
+	}
+}
+
+static void timespec_clear(struct timespec *a) {
+	a->tv_sec = 0;
+}
 
-static fd_set readfds;
-static fd_set writefds;
-static volatile bool running;
+static bool timespec_isset(const struct timespec *a) {
+	return a->tv_sec;
+}
 
 static int io_compare(const io_t *a, const io_t *b) {
 	return a->fd - b->fd;
 }
 
 static int timeout_compare(const timeout_t *a, const timeout_t *b) {
-	struct timeval diff;
-	timersub(&a->tv, &b->tv, &diff);
-	if(diff.tv_sec < 0)
+	if(a->tv.tv_sec < b->tv.tv_sec) {
 		return -1;
-	if(diff.tv_sec > 0)
+	} else if(a->tv.tv_sec > b->tv.tv_sec) {
 		return 1;
-	if(diff.tv_usec < 0)
+	} else if(a->tv.tv_nsec < b->tv.tv_nsec) {
 		return -1;
-	if(diff.tv_usec > 0)
+	} else if(a->tv.tv_nsec > b->tv.tv_nsec) {
 		return 1;
-	if(a < b)
+	} else if(a < b) {
 		return -1;
-	if(a > b)
+	} else if(a > b) {
 		return 1;
-	return 0;
+	} else {
+		return 0;
+	}
 }
 
-static splay_tree_t io_tree = {.compare = (splay_compare_t)io_compare};
-static splay_tree_t timeout_tree = {.compare = (splay_compare_t)timeout_compare};
-
-void io_add(io_t *io, io_cb_t cb, void *data, int fd, int flags) {
-	if(io->cb)
-		return;
+void io_add(event_loop_t *loop, io_t *io, io_cb_t cb, void *data, int fd, int flags) {
+	assert(!io->cb);
 
 	io->fd = fd;
 	io->cb = cb;
 	io->data = data;
 	io->node.data = io;
 
-	io_set(io, flags);
+	io_set(loop, io, flags);
 
-	if(!splay_insert_node(&io_tree, &io->node))
-		abort();
+	splay_node_t *node = splay_insert_node(&loop->ios, &io->node);
+	assert(node);
+	(void)node;
 }
 
-void io_set(io_t *io, int flags) {
+void io_set(event_loop_t *loop, io_t *io, int flags) {
+	assert(io->cb);
+
 	io->flags = flags;
 
-	if(flags & IO_READ)
-		FD_SET(io->fd, &readfds);
-	else
-		FD_CLR(io->fd, &readfds);
+	if(flags & IO_READ) {
+		FD_SET(io->fd, &loop->readfds);
+	} else {
+		FD_CLR(io->fd, &loop->readfds);
+	}
 
-	if(flags & IO_WRITE)
-		FD_SET(io->fd, &writefds);
-	else
-		FD_CLR(io->fd, &writefds);
+	if(flags & IO_WRITE) {
+		FD_SET(io->fd, &loop->writefds);
+	} else {
+		FD_CLR(io->fd, &loop->writefds);
+	}
 }
 
-void io_del(io_t *io) {
-	if(!io->cb)
-		return;
+void io_del(event_loop_t *loop, io_t *io) {
+	assert(io->cb);
 
-	io_set(io, 0);
+	loop->deletion = true;
 
-	splay_unlink_node(&io_tree, &io->node);
+	io_set(loop, io, 0);
+
+	splay_unlink_node(&loop->ios, &io->node);
 	io->cb = NULL;
 }
 
-void timeout_add(timeout_t *timeout, timeout_cb_t cb, void *data, struct timeval *tv) {
+void timeout_add(event_loop_t *loop, timeout_t *timeout, timeout_cb_t cb, void *data, struct timespec *tv) {
 	timeout->cb = cb;
 	timeout->data = data;
 	timeout->node.data = timeout;
 
-	timeout_set(timeout, tv);
+	timeout_set(loop, timeout, tv);
 }
 
-void timeout_set(timeout_t *timeout, struct timeval *tv) {
-	if(timerisset(&timeout->tv))
-		splay_unlink_node(&timeout_tree, &timeout->node);
+void timeout_set(event_loop_t *loop, timeout_t *timeout, struct timespec *tv) {
+	assert(timeout->cb);
+
+	if(timespec_isset(&timeout->tv)) {
+		splay_unlink_node(&loop->timeouts, &timeout->node);
+	}
 
-	if(!now.tv_sec)
-		gettimeofday(&now, NULL);
+	if(!loop->now.tv_sec) {
+		clock_gettime(EVENT_CLOCK, &loop->now);
+	}
 
-	timeradd(&now, tv, &timeout->tv);
+	timespec_add(&loop->now, tv, &timeout->tv);
 
-	if(!splay_insert_node(&timeout_tree, &timeout->node))
+	if(!splay_insert_node(&loop->timeouts, &timeout->node)) {
 		abort();
+	}
+
+	loop->deletion = true;
 }
 
-void timeout_del(timeout_t *timeout) {
-	if(!timeout->cb)
+static void timeout_disable(event_loop_t *loop, timeout_t *timeout) {
+	splay_unlink_node(&loop->timeouts, &timeout->node);
+	timespec_clear(&timeout->tv);
+}
+
+void timeout_del(event_loop_t *loop, timeout_t *timeout) {
+	if(!timeout->cb) {
 		return;
+	}
 
-	splay_unlink_node(&timeout_tree, &timeout->node);
-	timeout->cb = 0;
-	timeout->tv = (struct timeval){0, 0};
+	if(timespec_isset(&timeout->tv)) {
+		timeout_disable(loop, timeout);
+	}
+
+	timeout->cb = NULL;
+	loop->deletion = true;
 }
 
-#ifndef HAVE_MINGW
 static int signal_compare(const signal_t *a, const signal_t *b) {
-	return a->signum - b->signum;
+	return (int)a->signum - (int)b->signum;
 }
 
-static io_t signalio;
-static int pipefd[2] = {-1, -1};
-static splay_tree_t signal_tree = {.compare = (splay_compare_t)signal_compare};
+static void signalio_handler(event_loop_t *loop, void *data, int flags) {
+	(void)data;
+	(void)flags;
+	unsigned char signum;
 
-static void signal_handler(int signum) {
-	unsigned char num = signum;
-	write(pipefd[1], &num, 1);
+	if(read(loop->pipefd[0], &signum, 1) != 1) {
+		return;
+	}
+
+	signal_t *sig = splay_search(&loop->signals, &(signal_t) {
+		.signum = signum
+	});
+
+	if(sig) {
+		sig->set = false;
+		sig->cb(loop, sig->data);
+	}
 }
 
-static void signalio_handler(void *data, int flags) {
-	unsigned char signum;
-	if(read(pipefd[0], &signum, 1) != 1)
-		return;
+static void pipe_init(event_loop_t *loop) {
+	int result = pipe(loop->pipefd);
+	assert(result == 0);
 
-	signal_t *sig = splay_search(&signal_tree, &((signal_t){.signum = signum}));
-	if(sig)
-		sig->cb(sig->data);
+	if(result == 0) {
+		io_add(loop, &loop->signalio, signalio_handler, NULL, loop->pipefd[0], IO_READ);
+	}
 }
 
-static void pipe_init(void) {
-	if(!pipe(pipefd))
-		io_add(&signalio, signalio_handler, NULL, pipefd[0], IO_READ);
+static void pipe_exit(event_loop_t *loop) {
+	io_del(loop, &loop->signalio);
+
+	close(loop->pipefd[0]);
+	close(loop->pipefd[1]);
+
+	loop->pipefd[0] = -1;
+	loop->pipefd[1] = -1;
 }
 
-void signal_add(signal_t *sig, signal_cb_t cb, void *data, int signum) {
-	if(sig->cb)
+void signal_trigger(event_loop_t *loop, signal_t *sig) {
+	if(sig->set) {
 		return;
+	}
+
+	uint8_t signum = sig->signum;
+	sig->set = true;
+	write(loop->pipefd[1], &signum, 1);
+	return;
+}
+
+void signal_add(event_loop_t *loop, signal_t *sig, signal_cb_t cb, void *data, uint8_t signum) {
+	assert(!sig->cb);
 
 	sig->cb = cb;
 	sig->data = data;
 	sig->signum = signum;
+	sig->set = false;
 	sig->node.data = sig;
 
-	if(pipefd[0] == -1)
-		pipe_init();
-
-	signal(sig->signum, signal_handler);
+	if(loop->pipefd[0] == -1) {
+		pipe_init(loop);
+	}
 
-	if(!splay_insert_node(&signal_tree, &sig->node))
+	if(!splay_insert_node(&loop->signals, &sig->node)) {
 		abort();
+	}
 }
 
-void signal_del(signal_t *sig) {
-	if(!sig->cb)
-		return;
+void signal_del(event_loop_t *loop, signal_t *sig) {
+	assert(sig->cb);
 
-	signal(sig->signum, SIG_DFL);
+	loop->deletion = true;
 
-	splay_unlink_node(&signal_tree, &sig->node);
+	splay_unlink_node(&loop->signals, &sig->node);
 	sig->cb = NULL;
+
+	if(!loop->signals.count && loop->pipefd[0] != -1) {
+		pipe_exit(loop);
+	}
+}
+
+void idle_set(event_loop_t *loop, idle_cb_t cb, void *data) {
+	loop->idle_cb = cb;
+	loop->idle_data = data;
 }
-#endif
 
-bool event_loop(void) {
-	running = true;
+bool event_loop_run(event_loop_t *loop, pthread_mutex_t *mutex) {
+	assert(mutex);
 
 	fd_set readable;
 	fd_set writable;
 
-	while(running) {
-		gettimeofday(&now, NULL);
-		struct timeval diff, *tv = NULL;
+	while(loop->running) {
+		clock_gettime(EVENT_CLOCK, &loop->now);
+		struct timespec it, ts = {3600, 0};
 
-		while(timeout_tree.head) {
-			timeout_t *timeout = timeout_tree.head->data;
-			timersub(&timeout->tv, &now, &diff);
+		while(loop->timeouts.head) {
+			timeout_t *timeout = loop->timeouts.head->data;
 
-			if(diff.tv_sec < 0) {
-				timeout->cb(timeout->data);
-				if(timercmp(&timeout->tv, &now, <))
-					timeout_del(timeout);
+			if(timespec_lt(&timeout->tv, &loop->now)) {
+				timeout_disable(loop, timeout);
+				timeout->cb(loop, timeout->data);
 			} else {
-				tv = &diff;
+				timespec_sub(&timeout->tv, &loop->now, &ts);
 				break;
 			}
 		}
 
-		memcpy(&readable, &readfds, sizeof readable);
-		memcpy(&writable, &writefds, sizeof writable);
+		if(loop->idle_cb) {
+			it = loop->idle_cb(loop, loop->idle_data);
+
+			if(it.tv_sec >= 0 && timespec_lt(&it, &ts)) {
+				ts = it;
+			}
+		}
+
+		memcpy(&readable, &loop->readfds, sizeof(readable));
+		memcpy(&writable, &loop->writefds, sizeof(writable));
 
 		int fds = 0;
 
-		if(io_tree.tail) {
-			io_t *last = io_tree.tail->data;
+		if(loop->ios.tail) {
+			io_t *last = loop->ios.tail->data;
 			fds = last->fd + 1;
 		}
 
-#ifdef HAVE_MINGW
-		LeaveCriticalSection(&mutex);
-#endif
-		int n = select(fds, &readable, &writable, NULL, tv);
-#ifdef HAVE_MINGW
-		EnterCriticalSection(&mutex);
+		// release mesh mutex during select
+		pthread_mutex_unlock(mutex);
+
+#ifdef HAVE_PSELECT
+		int n = pselect(fds, &readable, &writable, NULL, &ts, NULL);
+#else
+		struct timeval tv = {ts.tv_sec, ts.tv_nsec / 1000};
+		int n = select(fds, &readable, &writable, NULL, (struct timeval *)&tv);
 #endif
 
+		pthread_mutex_lock(mutex);
+
+		clock_gettime(EVENT_CLOCK, &loop->now);
+
 		if(n < 0) {
-			if(sockwouldblock(errno))
+			if(sockwouldblock(errno)) {
 				continue;
-			else
+			} else {
 				return false;
+			}
 		}
 
-		if(!n)
+		if(!n) {
 			continue;
+		}
+
+		// Normally, splay_each allows the current node to be deleted. However,
+		// it can be that one io callback triggers the deletion of another io,
+		// so we have to detect this and break the loop.
 
-		for splay_each(io_t, io, &io_tree) {
-			if(FD_ISSET(io->fd, &writable))
-				io->cb(io->data, IO_WRITE);
-			else if(FD_ISSET(io->fd, &readable))
-				io->cb(io->data, IO_READ);
+		loop->deletion = false;
+
+		for splay_each(io_t, io, &loop->ios) {
+			if(FD_ISSET(io->fd, &writable) && io->cb) {
+				io->cb(loop, io->data, IO_WRITE);
+			}
+
+			if(loop->deletion) {
+				break;
+			}
+
+			if(FD_ISSET(io->fd, &readable) && io->cb) {
+				io->cb(loop, io->data, IO_READ);
+			}
+
+			if(loop->deletion) {
+				break;
+			}
 		}
 	}
 
 	return true;
 }
 
-void event_flush_output(void) {
-	for splay_each(io_t, io, &io_tree)
-		if(FD_ISSET(io->fd, &writefds))
-			io->cb(io->data, IO_WRITE);
+void event_flush_output(event_loop_t *loop) {
+	for splay_each(io_t, io, &loop->ios)
+		if(FD_ISSET(io->fd, &loop->writefds)) {
+			io->cb(loop, io->data, IO_WRITE);
+		}
 }
 
-void event_exit(void) {
-	running = false;
+void event_loop_start(event_loop_t *loop) {
+	loop->running = true;
+}
+
+void event_loop_stop(event_loop_t *loop) {
+	loop->running = false;
+}
+
+void event_loop_init(event_loop_t *loop) {
+	loop->ios.compare = (splay_compare_t)io_compare;
+	loop->timeouts.compare = (splay_compare_t)timeout_compare;
+	loop->signals.compare = (splay_compare_t)signal_compare;
+	loop->pipefd[0] = -1;
+	loop->pipefd[1] = -1;
+	clock_gettime(EVENT_CLOCK, &loop->now);
+}
+
+void event_loop_exit(event_loop_t *loop) {
+	assert(!loop->ios.count);
+	assert(!loop->timeouts.count);
+	assert(!loop->signals.count);
+
+	for splay_each(io_t, io, &loop->ios) {
+		splay_unlink_node(&loop->ios, node);
+	}
+
+	for splay_each(timeout_t, timeout, &loop->timeouts) {
+		splay_unlink_node(&loop->timeouts, node);
+	}
+
+	for splay_each(signal_t, signal, &loop->signals) {
+		splay_unlink_node(&loop->signals, node);
+	}
 }