X-Git-Url: https://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Fio%2Fpoll.c;h=cddc3cacd266e5b80392d91af367d689da093bd6;hp=e3f595c9884c0d2fcea42d598ca3321d067069a8;hb=aae40e493625a07f4ac95476664447546b28661a;hpb=710d42d071a10093077d30d6e521f9599a9bc997

diff --git a/ccan/io/poll.c b/ccan/io/poll.c
index e3f595c9..cddc3cac 100644
--- a/ccan/io/poll.c
+++ b/ccan/io/poll.c
@@ -8,71 +8,43 @@
 #include <sys/socket.h>
 #include <limits.h>
 #include <errno.h>
+#include <ccan/time/time.h>
+#include <ccan/timer/timer.h>
 
-static size_t num_fds = 0, max_fds = 0, num_closing = 0, num_waiting = 0;
-static bool some_always = false;
+static size_t num_fds = 0, max_fds = 0, num_waiting = 0;
 static struct pollfd *pollfds = NULL;
 static struct fd **fds = NULL;
-static struct timers timeouts;
-#ifdef DEBUG
-static unsigned int io_loop_level;
-static struct io_conn *free_later;
-static void io_loop_enter(void)
-{
-	io_loop_level++;
-}
-static void io_loop_exit(void)
-{
-	io_loop_level--;
-	if (io_loop_level == 0) {
-		/* Delayed free. */
-		while (free_later) {
-			struct io_conn *c = free_later;
-			free_later = c->finish_arg;
-			io_alloc.free(c);
-		}
-	}
-}
-static void free_conn(struct io_conn *conn)
-{
-	/* Only free on final exit: chain via finish. */
-	if (io_loop_level > 1) {
-		struct io_conn *c;
-		for (c = free_later; c; c = c->finish_arg)
-			assert(c != conn);
-		conn->finish_arg = free_later;
-		free_later = conn;
-	} else
-		io_alloc.free(conn);
-}
-#else
-static void io_loop_enter(void)
-{
-}
-static void io_loop_exit(void)
-{
-}
-static void free_conn(struct io_conn *conn)
+static LIST_HEAD(closing);
+static LIST_HEAD(always);
+static struct timeabs (*nowfn)(void) = time_now;
+
+struct timeabs (*io_time_override(struct timeabs (*now)(void)))(void)
 {
-	io_alloc.free(conn);
+	struct timeabs (*old)(void) = nowfn;
+	nowfn = now;
+	return old;
 }
-#endif
 
 static bool add_fd(struct fd *fd, short events)
 {
+	if (!max_fds) {
+		assert(num_fds == 0);
+		pollfds = tal_arr(NULL, struct pollfd, 8);
+		if (!pollfds)
+			return false;
+		fds = tal_arr(pollfds, struct fd *, 8);
+		if (!fds)
+			return false;
+		max_fds = 8;
+	}
+
 	if (num_fds + 1 > max_fds) {
-		struct pollfd *newpollfds;
-		struct fd **newfds;
-		size_t num = max_fds ? max_fds * 2 : 8;
+		size_t num = max_fds * 2;
 
-		newpollfds = io_alloc.realloc(pollfds, sizeof(*newpollfds)*num);
-		if (!newpollfds)
+		if (!tal_resize(&pollfds, num))
 			return false;
-		pollfds = newpollfds;
-		newfds = io_alloc.realloc(fds, sizeof(*newfds) * num);
-		if (!newfds)
+		if (!tal_resize(&fds, num))
 			return false;
-		fds = newfds;
 		max_fds = num;
 	}
 
@@ -106,24 +78,20 @@ static void del_fd(struct fd *fd)
 		fds[n] = fds[num_fds-1];
 		assert(fds[n]->backend_info == num_fds-1);
 		fds[n]->backend_info = n;
-		/* If that happens to be a duplex, move that too. */
-		if (!fds[n]->listener) {
-			struct io_conn *c = (void *)fds[n];
-			if (c->duplex) {
-				assert(c->duplex->fd.backend_info == num_fds-1);
-				c->duplex->fd.backend_info = n;
-			}
-		}
 	} else if (num_fds == 1) {
 		/* Free everything when no more fds. */
-		io_alloc.free(pollfds);
-		io_alloc.free(fds);
-		pollfds = NULL;
+		pollfds = tal_free(pollfds);
 		fds = NULL;
 		max_fds = 0;
 	}
 	num_fds--;
 	fd->backend_info = -1;
+
+	/* Closing a local socket doesn't wake poll() because other end
+	 * has them open.  See 2.6.  When should I use shutdown()?
+	 * in http://www.faqs.org/faqs/unix-faq/socket/ */
+	shutdown(fd->fd, SHUT_RDWR);
+
 	close(fd->fd);
 }
 
@@ -134,78 +102,82 @@ bool add_listener(struct io_listener *l)
 	return true;
 }
 
-void backend_plan_changed(struct io_conn *conn)
+void remove_from_always(struct io_conn *conn)
 {
-	struct pollfd *pfd;
+	list_del_init(&conn->always);
+}
 
-	/* This can happen with debugging and delayed free... */
-	if (conn->fd.backend_info == -1)
-		return;
+void backend_new_closing(struct io_conn *conn)
+{
+	/* In case it's on always list, remove it. */
+	list_del_init(&conn->always);
+	list_add_tail(&closing, &conn->closing);
+}
 
-	pfd = &pollfds[conn->fd.backend_info];
+void backend_new_always(struct io_conn *conn)
+{
+	/* In case it's already in always list. */
+	list_del(&conn->always);
+	list_add_tail(&always, &conn->always);
+}
+
+void backend_new_plan(struct io_conn *conn)
+{
+	struct pollfd *pfd = &pollfds[conn->fd.backend_info];
 
 	if (pfd->events)
 		num_waiting--;
 
-	pfd->events = conn->plan.pollflag & (POLLIN|POLLOUT);
-	if (conn->duplex) {
-		int mask = conn->duplex->plan.pollflag & (POLLIN|POLLOUT);
-		/* You can't *both* read/write. */
-		assert(!mask || pfd->events != mask);
-		pfd->events |= mask;
-	}
+	pfd->events = 0;
+	if (conn->plan[IO_IN].status == IO_POLLING)
+		pfd->events |= POLLIN;
+	if (conn->plan[IO_OUT].status == IO_POLLING)
+		pfd->events |= POLLOUT;
+
 	if (pfd->events) {
 		num_waiting++;
 		pfd->fd = conn->fd.fd;
-	} else
+	} else {
 		pfd->fd = -conn->fd.fd;
-
-	if (!conn->plan.next)
-		num_closing++;
-
-	if (conn->plan.pollflag == POLLALWAYS)
-		some_always = true;
+	}
 }
 
-bool add_conn(struct io_conn *c)
+void backend_wake(const void *wait)
 {
-	if (!add_fd(&c->fd, c->plan.pollflag & (POLLIN|POLLOUT)))
-		return false;
-	/* Immediate close is allowed. */
-	if (!c->plan.next)
-		num_closing++;
-	if (c->plan.pollflag == POLLALWAYS)
-		some_always = true;
-	return true;
+	unsigned int i;
+
+	for (i = 0; i < num_fds; i++) {
+		struct io_conn *c;
+
+		/* Ignore listeners */
+		if (fds[i]->listener)
+			continue;
+
+		c = (void *)fds[i];
+		if (c->plan[IO_IN].status == IO_WAITING
+		    && c->plan[IO_IN].arg.u1.const_vp == wait)
+			io_do_wakeup(c, IO_IN);
+
+		if (c->plan[IO_OUT].status == IO_WAITING
+		    && c->plan[IO_OUT].arg.u1.const_vp == wait)
+			io_do_wakeup(c, IO_OUT);
+	}
 }
 
-bool add_duplex(struct io_conn *c)
+bool add_conn(struct io_conn *c)
 {
-	c->fd.backend_info = c->duplex->fd.backend_info;
-	backend_plan_changed(c);
-	return true;
+	return add_fd(&c->fd, 0);
 }
 
-void backend_del_conn(struct io_conn *conn)
+static void del_conn(struct io_conn *conn)
 {
-	if (timeout_active(conn))
-		backend_del_timeout(conn);
-	io_alloc.free(conn->timeout);
-	if (conn->duplex) {
-		/* In case fds[] pointed to the other one. */
-		assert(conn->duplex->fd.backend_info == conn->fd.backend_info);
-		fds[conn->fd.backend_info] = &conn->duplex->fd;
-		conn->duplex->duplex = NULL;
-		conn->fd.backend_info = -1;
-	} else
-		del_fd(&conn->fd);
-	num_closing--;
+	del_fd(&conn->fd);
 	if (conn->finish) {
 		/* Saved by io_close */
-		errno = conn->plan.u1.s;
+		errno = conn->plan[IO_IN].arg.u1.s;
 		conn->finish(conn, conn->finish_arg);
 	}
-	free_conn(conn);
+	tal_free(conn);
 }
 
 void del_listener(struct io_listener *l)
@@ -213,12 +185,6 @@ void del_listener(struct io_listener *l)
 	del_fd(&l->fd);
 }
 
-static void set_plan(struct io_conn *conn, struct io_plan plan)
-{
-	conn->plan = plan;
-	backend_plan_changed(conn);
-}
-
 static void accept_conn(struct io_listener *l)
 {
 	int fd = accept(l->fd.fd, NULL, NULL);
@@ -226,135 +192,97 @@ static void accept_conn(struct io_listener *l)
 	/* FIXME: What to do here? */
 	if (fd < 0)
 		return;
-	l->init(fd, l->arg);
+
+	io_new_conn(l->ctx, fd, l->init, l->arg);
 }
 
 /* It's OK to miss some, as long as we make progress. */
-static bool finish_conns(struct io_conn **ready)
+static bool close_conns(void)
 {
-	unsigned int i;
+	bool ret = false;
+	struct io_conn *conn;
 
-	for (i = 0; !io_loop_return && i < num_fds; i++) {
-		struct io_conn *c, *duplex;
-
-		if (!num_closing)
-			break;
+	while ((conn = list_pop(&closing, struct io_conn, closing)) != NULL) {
+		assert(conn->plan[IO_IN].status == IO_CLOSING);
+		assert(conn->plan[IO_OUT].status == IO_CLOSING);
 
-		if (fds[i]->listener)
-			continue;
-		c = (void *)fds[i];
-		for (duplex = c->duplex; c; c = duplex, duplex = NULL) {
-			if (!c->plan.next) {
-				if (doing_debug_on(c) && ready) {
-					*ready = c;
-					return true;
-				}
-				backend_del_conn(c);
-				i--;
-			}
-		}
+		del_conn(conn);
+		ret = true;
 	}
-	return false;
-}
-
-void backend_add_timeout(struct io_conn *conn, struct timespec duration)
-{
-	if (!timeouts.base)
-		timers_init(&timeouts, time_now());
-	timer_add(&timeouts, &conn->timeout->timer,
-		  time_add(time_now(), duration));
-	conn->timeout->conn = conn;
-}
-
-void backend_del_timeout(struct io_conn *conn)
-{
-	assert(conn->timeout->conn == conn);
-	timer_del(&timeouts, &conn->timeout->timer);
-	conn->timeout->conn = NULL;
+	return ret;
 }
 
-static void handle_always(void)
+static bool handle_always(void)
 {
-	int i;
+	bool ret = false;
+	struct io_conn *conn;
 
-	some_always = false;
+	while ((conn = list_pop(&always, struct io_conn, always)) != NULL) {
+		assert(conn->plan[IO_IN].status == IO_ALWAYS
+		       || conn->plan[IO_OUT].status == IO_ALWAYS);
 
-	for (i = 0; i < num_fds && !io_loop_return; i++) {
-		struct io_conn *c = (void *)fds[i];
-
-		if (fds[i]->listener)
-			continue;
-
-		if (c->plan.pollflag == POLLALWAYS)
-			io_ready(c);
-
-		if (c->duplex && c->duplex->plan.pollflag == POLLALWAYS)
-			io_ready(c->duplex);
+		/* Re-initialize, for next time. */
+		list_node_init(&conn->always);
+		io_do_always(conn);
+		ret = true;
 	}
+	return ret;
 }
 
 /* This is the main loop. */
-void *do_io_loop(struct io_conn **ready)
+void *io_loop(struct timers *timers, struct timer **expired)
 {
 	void *ret;
 
-	io_loop_enter();
-
-	while (!io_loop_return) {
-		int i, r, timeout = INT_MAX;
-		struct timespec now;
-		bool some_timeouts = false;
-
-		if (timeouts.base) {
-			struct timespec first;
-			struct list_head expired;
-			struct io_timeout *t;
+	/* if timers is NULL, expired must be.  If not, not. */
+	assert(!timers == !expired);
 
-			now = time_now();
+	/* Make sure this is NULL if we exit for some other reason. */
+	if (expired)
+		*expired = NULL;
 
-			/* Call functions for expired timers. */
-			timers_expire(&timeouts, now, &expired);
-			while ((t = list_pop(&expired, struct io_timeout, timer.list))) {
-				struct io_conn *conn = t->conn;
-				/* Clear, in case timer re-adds */
-				t->conn = NULL;
-				set_current(conn);
-				set_plan(conn, t->next(conn, t->next_arg));
-				some_timeouts = true;
-			}
-
-			/* Now figure out how long to wait for the next one. */
-			if (timer_earliest(&timeouts, &first)) {
-				uint64_t f = time_to_msec(time_sub(first, now));
-				if (f < INT_MAX)
-					timeout = f;
-			}
-		}
+	while (!io_loop_return) {
+		int i, r, ms_timeout = -1;
 
-		if (num_closing) {
-			/* If this finishes a debugging con, return now. */
-			if (finish_conns(ready))
-				return NULL;
+		if (close_conns()) {
 			/* Could have started/finished more. */
 			continue;
 		}
 
-		/* debug can recurse on io_loop; anything can change. */
-		if (doing_debug() && some_timeouts)
-			continue;
-
-		if (some_always) {
-			handle_always();
+		if (handle_always()) {
+			/* Could have started/finished more. */
 			continue;
 		}
 
+		/* Everything closed? */
 		if (num_fds == 0)
 			break;
 
 		/* You can't tell them all to go to sleep! */
 		assert(num_waiting);
 
-		r = poll(pollfds, num_fds, timeout);
+		if (timers) {
+			struct timeabs now, first;
+
+			now = nowfn();
+
+			/* Call functions for expired timers. */
+			*expired = timers_expire(timers, now);
+			if (*expired)
+				break;
+
+			/* Now figure out how long to wait for the next one. */
+			if (timer_earliest(timers, &first)) {
+				uint64_t next;
+				next = time_to_msec(time_between(first, now));
+				if (next < INT_MAX)
+					ms_timeout = next;
+				else
+					ms_timeout = INT_MAX;
+			}
+		}
+
+		r = poll(pollfds, num_fds, ms_timeout);
 		if (r < 0)
 			break;
 
@@ -372,62 +300,19 @@ void *do_io_loop(struct io_conn **ready)
 				}
 			} else if (events & (POLLIN|POLLOUT)) {
 				r--;
-				if (c->duplex) {
-					int mask = c->duplex->plan.pollflag;
-					if (events & mask) {
-						if (doing_debug_on(c->duplex)
-							&& ready) {
-							*ready = c->duplex;
-							return NULL;
-						}
-						io_ready(c->duplex);
-						events &= ~mask;
-						/* debug can recurse;
-						 * anything can change. */
-						if (doing_debug())
-							break;
-
-						/* If no events, or it closed
-						 * the duplex, continue. */
-						if (!(events&(POLLIN|POLLOUT))
-						    || !c->plan.next)
-							continue;
-					}
-				}
-				if (doing_debug_on(c) && ready) {
-					*ready = c;
-					return NULL;
-				}
-				io_ready(c);
-				/* debug can recurse; anything can change. */
-				if (doing_debug())
-					break;
+				io_ready(c, events);
 			} else if (events & (POLLHUP|POLLNVAL|POLLERR)) {
 				r--;
-				set_current(c);
 				errno = EBADF;
-				set_plan(c, io_close());
-				if (c->duplex) {
-					set_current(c->duplex);
-					set_plan(c->duplex, io_close());
-				}
+				io_close(c);
 			}
 		}
 	}
 
-	while (num_closing && !io_loop_return) {
-		if (finish_conns(ready))
-			return NULL;
-	}
+	close_conns();
 
 	ret = io_loop_return;
 	io_loop_return = NULL;
 
-	io_loop_exit();
 	return ret;
 }
-
-void *io_loop(void)
-{
-	return do_io_loop(NULL);
-}