From: Rusty Russell <rusty@rustcorp.com.au>
Date: Mon, 4 Aug 2014 08:13:21 +0000 (+0930)
Subject: ccan/io: implement timeouts.
X-Git-Url: http://git.ozlabs.org/?p=ccan;a=commitdiff_plain;h=94dd4c2bddd0dc080ad5b85465fa3f45f486967a

ccan/io: implement timeouts.

We do this by the simplest method: return from io_loop() and let the caller
sort them out.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---

diff --git a/ccan/io/_info b/ccan/io/_info
index 7fc6ac61..2e0018ad 100644
--- a/ccan/io/_info
+++ b/ccan/io/_info
@@ -118,7 +118,7 @@
  * 	io_set_finish(reader, finish, &from);
  * 	io_new_conn(NULL, STDOUT_FILENO, write_out, &from);
  *
- * 	io_loop();
+ * 	io_loop(NULL, NULL);
  * 	wait(&status);
  *
  * 	return WIFEXITED(status) ? WEXITSTATUS(status) : 2;
@@ -133,7 +133,10 @@ int main(int argc, char *argv[])
 		return 1;
 
 	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/list\n");
 		printf("ccan/tal\n");
+		printf("ccan/time\n");
+		printf("ccan/timer\n");
 		printf("ccan/typesafe_cb\n");
 		return 0;
 	}
diff --git a/ccan/io/io.h b/ccan/io/io.h
index d4ba2d87..165ff6f6 100644
--- a/ccan/io/io.h
+++ b/ccan/io/io.h
@@ -6,6 +6,9 @@
 #include <stdbool.h>
 #include <unistd.h>
 
+struct timers;
+struct list_head;
+
 /**
  * struct io_plan - a plan for input or output.
  *
@@ -169,7 +172,7 @@ struct io_listener *io_new_listener_(const tal_t *ctx, int fd,
  * ...
  *	struct io_listener *l = do_listen("8111");
  *	if (l) {
- *		io_loop();
+ *		io_loop(NULL, NULL);
  *		io_close_listener(l);
  *	}
  */
@@ -553,14 +556,17 @@ struct io_plan *io_close_cb(struct io_conn *, void *unused);
 
 /**
  * io_loop - process fds until all closed on io_break.
+ * @timers - timers which are waiting to go off (or NULL for none)
+ * @expired - a list filled with expired timers (can be NULL if @timers is)
  *
  * This is the core loop; it exits with the io_break() arg, or NULL if
- * all connections and listeners are closed.
+ * all connections and listeners are closed, or with @expired set to a
+ * list of expired timers (if @timers isn't NULL).
  *
  * Example:
- *	io_loop();
+ *	io_loop(NULL, NULL);
  */
-void *io_loop(void);
+void *io_loop(struct timers *timers, struct list_head *expired);
 
 /**
  * io_conn_fd - get the fd from a connection.
diff --git a/ccan/io/poll.c b/ccan/io/poll.c
index c1a62452..e4058766 100644
--- a/ccan/io/poll.c
+++ b/ccan/io/poll.c
@@ -8,6 +8,9 @@
 #include <sys/socket.h>
 #include <limits.h>
 #include <errno.h>
+#include <ccan/list/list.h>
+#include <ccan/time/time.h>
+#include <ccan/timer/timer.h>
 
 static size_t num_fds = 0, max_fds = 0, num_waiting = 0;
 static struct pollfd *pollfds = NULL;
@@ -223,12 +226,19 @@ static bool handle_always(void)
 }
 
 /* This is the main loop. */
-void *io_loop(void)
+void *io_loop(struct timers *timers, struct list_head *expired)
 {
 	void *ret;
 
+	/* if timers is NULL, expired must be.  If not, not. */
+	assert(!timers == !expired);
+
+	/* Make sure this is empty if we exit for some other reason. */
+	if (expired)
+		list_head_init(expired);
+
 	while (!io_loop_return) {
-		int i, r;
+		int i, r, ms_timeout = -1;
 
 		if (close_conns()) {
 			/* Could have started/finished more. */
@@ -247,7 +257,28 @@ void *io_loop(void)
 		/* You can't tell them all to go to sleep! */
 		assert(num_waiting);
 
-		r = poll(pollfds, num_fds, -1);
+		if (timers) {
+			struct timeabs now, first;
+
+			now = time_now();
+
+			/* Call functions for expired timers. */
+			timers_expire(timers, now, expired);
+			if (!list_empty(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;
 
diff --git a/ccan/io/test/run-01-start-finish.c b/ccan/io/test/run-01-start-finish.c
index b1ce78d3..eb2c90a6 100644
--- a/ccan/io/test/run-01-start-finish.c
+++ b/ccan/io/test/run-01-start-finish.c
@@ -88,7 +88,7 @@ int main(void)
 		exit(0);
 	}
 	freeaddrinfo(addrinfo);
-	ok1(io_loop() == &state + 1);
+	ok1(io_loop(NULL, NULL) == &state + 1);
 	ok1(state == 2);
 	io_close_listener(l);
 	ok1(wait(&state));
diff --git a/ccan/io/test/run-02-read.c b/ccan/io/test/run-02-read.c
index 4a043359..b43bb8bf 100644
--- a/ccan/io/test/run-02-read.c
+++ b/ccan/io/test/run-02-read.c
@@ -99,7 +99,7 @@ int main(void)
 		exit(0);
 	}
 	freeaddrinfo(addrinfo);
-	ok1(io_loop() == d);
+	ok1(io_loop(NULL, NULL) == d);
 	ok1(d->state == 2);
 	ok1(memcmp(d->buf, "hellothere", sizeof(d->buf)) == 0);
 	free(d);
diff --git a/ccan/io/test/run-03-readpartial.c b/ccan/io/test/run-03-readpartial.c
index 7b360638..2d15c2f5 100644
--- a/ccan/io/test/run-03-readpartial.c
+++ b/ccan/io/test/run-03-readpartial.c
@@ -106,7 +106,7 @@ int main(void)
 		free(d);
 		exit(0);
 	}
-	ok1(io_loop() == d);
+	ok1(io_loop(NULL, NULL) == d);
 	ok1(d->state == 2);
 	ok1(d->bytes > 0);
 	ok1(d->bytes <= sizeof(d->buf));
@@ -125,7 +125,7 @@ int main(void)
 		exit(0);
 	}
 	d->state = 0;
-	ok1(io_loop() == d);
+	ok1(io_loop(NULL, NULL) == d);
 	ok1(d->state == 2);
 	ok1(d->bytes > 0);
 	ok1(d->bytes <= strlen("hi"));
diff --git a/ccan/io/test/run-04-writepartial.c b/ccan/io/test/run-04-writepartial.c
index 4ca21a32..011bbc89 100644
--- a/ccan/io/test/run-04-writepartial.c
+++ b/ccan/io/test/run-04-writepartial.c
@@ -109,7 +109,7 @@ int main(void)
 		free(d);
 		exit(0);
 	}
-	ok1(io_loop() == d);
+	ok1(io_loop(NULL, NULL) == d);
 	ok1(d->state == 2);
 	ok1(d->bytes > 0);
 	ok1(d->bytes <= 1024*1024);
diff --git a/ccan/io/test/run-05-write.c b/ccan/io/test/run-05-write.c
index 2e744cff..b17ef83a 100644
--- a/ccan/io/test/run-05-write.c
+++ b/ccan/io/test/run-05-write.c
@@ -110,7 +110,7 @@ int main(void)
 		free(d);
 		exit(0);
 	}
-	ok1(io_loop() == d);
+	ok1(io_loop(NULL, NULL) == d);
 	ok1(d->state == 2);
 
 	ok1(wait(&status));
diff --git a/ccan/io/test/run-06-idle.c b/ccan/io/test/run-06-idle.c
index d01cb31f..8f3d5410 100644
--- a/ccan/io/test/run-06-idle.c
+++ b/ccan/io/test/run-06-idle.c
@@ -143,7 +143,7 @@ int main(void)
 	}
 	freeaddrinfo(addrinfo);
 
-	ok1(io_loop() == d);
+	ok1(io_loop(NULL, NULL) == d);
 	ok1(d->state == 4);
 	ok1(memcmp(d->buf, "hellothere", sizeof(d->buf)) == 0);
 	free(d);
diff --git a/ccan/io/test/run-07-break.c b/ccan/io/test/run-07-break.c
index 1f69e9f5..dd192c4d 100644
--- a/ccan/io/test/run-07-break.c
+++ b/ccan/io/test/run-07-break.c
@@ -107,11 +107,11 @@ int main(void)
 		exit(0);
 	}
 	freeaddrinfo(addrinfo);
-	ok1(io_loop() == d);
+	ok1(io_loop(NULL, NULL) == d);
 	ok1(d->state == 1);
 	io_close_listener(l);
 
-	ok1(io_loop() == NULL);
+	ok1(io_loop(NULL, NULL) == NULL);
 	ok1(d->state == 3);
 	ok1(memcmp(d->buf, "hellothere", sizeof(d->buf)) == 0);
 	free(d);
diff --git a/ccan/io/test/run-08-hangup-on-idle.c b/ccan/io/test/run-08-hangup-on-idle.c
index 52309b4b..eb3dab3d 100644
--- a/ccan/io/test/run-08-hangup-on-idle.c
+++ b/ccan/io/test/run-08-hangup-on-idle.c
@@ -52,7 +52,7 @@ int main(void)
 		exit(0);
 	}
 
-	ok1(io_loop() == NULL);
+	ok1(io_loop(NULL, NULL) == NULL);
 	ok1(memcmp(buf, "hello there world", 16) == 0);
 
 	/* This exits depending on whether all tests passed */
diff --git a/ccan/io/test/run-08-read-after-hangup.c b/ccan/io/test/run-08-read-after-hangup.c
index 7b6731ec..14af5ae6 100644
--- a/ccan/io/test/run-08-read-after-hangup.c
+++ b/ccan/io/test/run-08-read-after-hangup.c
@@ -41,7 +41,7 @@ int main(void)
 	conn = io_new_conn(NULL, fds[0], init_waiter, NULL);
 	io_new_conn(conn, fds[1], init_writer, conn);
 
-	ok1(io_loop() == NULL);
+	ok1(io_loop(NULL, NULL) == NULL);
 	ok1(memcmp(inbuf, "EASYTEST", sizeof(inbuf)) == 0);
 
 	/* This exits depending on whether all tests passed */
diff --git a/ccan/io/test/run-09-connect.c b/ccan/io/test/run-09-connect.c
index 8f57f00d..09b33387 100644
--- a/ccan/io/test/run-09-connect.c
+++ b/ccan/io/test/run-09-connect.c
@@ -99,7 +99,7 @@ int main(void)
 		    addrinfo->ai_protocol);
 	ok1(io_new_conn(NULL, fd, setup_connect, addrinfo));
 
-	ok1(io_loop() == NULL);
+	ok1(io_loop(NULL, NULL) == NULL);
 	ok1(d->state == 2);
 	ok1(d2->state == 2);
 
diff --git a/ccan/io/test/run-10-many.c b/ccan/io/test/run-10-many.c
index fc48ecb5..3339a335 100644
--- a/ccan/io/test/run-10-many.c
+++ b/ccan/io/test/run-10-many.c
@@ -101,7 +101,7 @@ int main(void)
 	ok1(buf[i].writer);
 
 	/* They should eventually exit */
-	ok1(io_loop() == NULL);
+	ok1(io_loop(NULL, NULL) == NULL);
 
 	for (i = 0; i < NUM; i++) {
 		char b[sizeof(buf[0].buf)];
diff --git a/ccan/io/test/run-12-bidir.c b/ccan/io/test/run-12-bidir.c
index 0329b81f..bddd7fbe 100644
--- a/ccan/io/test/run-12-bidir.c
+++ b/ccan/io/test/run-12-bidir.c
@@ -119,7 +119,7 @@ int main(void)
 		exit(0);
 	}
 	freeaddrinfo(addrinfo);
-	ok1(io_loop() == NULL);
+	ok1(io_loop(NULL, NULL) == NULL);
 	ok1(d->state == 4);
 	ok1(d->done == 2);
 	ok1(memcmp(d->buf, "hellothere", sizeof(d->buf)) == 0);
diff --git a/ccan/io/test/run-13-all-idle.c b/ccan/io/test/run-13-all-idle.c
index 3701472b..7896b14f 100644
--- a/ccan/io/test/run-13-all-idle.c
+++ b/ccan/io/test/run-13-all-idle.c
@@ -23,7 +23,7 @@ int main(void)
 
 		ok1(pipe(fds) == 0);
 		io_new_conn(NULL, fds[0], setup_waiter, &status);
-		io_loop();
+		io_loop(NULL, NULL);
 		exit(1);
 	}
 
diff --git a/ccan/io/test/run-14-duplex-both-read.c b/ccan/io/test/run-14-duplex-both-read.c
index b52553aa..8cf22aa1 100644
--- a/ccan/io/test/run-14-duplex-both-read.c
+++ b/ccan/io/test/run-14-duplex-both-read.c
@@ -125,7 +125,7 @@ int main(void)
 		exit(0);
 	}
 	freeaddrinfo(addrinfo);
-	ok1(io_loop() == NULL);
+	ok1(io_loop(NULL, NULL) == NULL);
 	ok1(d->state == 5);
 	ok1(memcmp(d->buf, "hellothere", sizeof(d->buf)) == 0);
 	free(d);
diff --git a/ccan/io/test/run-15-timeout.c b/ccan/io/test/run-15-timeout.c
index 9224b0a9..e0a3b05e 100644
--- a/ccan/io/test/run-15-timeout.c
+++ b/ccan/io/test/run-15-timeout.c
@@ -3,55 +3,49 @@
 #include <ccan/io/poll.c>
 #include <ccan/io/io.c>
 #include <ccan/tap/tap.h>
+#include <ccan/time/time.h>
 #include <sys/wait.h>
 #include <stdio.h>
 #include <unistd.h>
 
-#if 0
 #ifndef PORT
 #define PORT "65015"
 #endif
 
 struct data {
+	struct timers timers;
 	int state;
+	struct io_conn *conn;
+	struct timer timer;
 	int timeout_usec;
-	bool timed_out;
 	char buf[4];
 };
 
-
-static struct io_plan no_timeout(struct io_conn *conn, struct data *d)
+static void finish_ok(struct io_conn *conn, struct data *d)
 {
-	ok1(d->state == 1);
 	d->state++;
-	return io_close();
+	io_break(d);
 }
 
-static struct io_plan timeout(struct io_conn *conn, struct data *d)
+static struct io_plan *no_timeout(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 1);
 	d->state++;
-	d->timed_out = true;
-	return io_close();
-}
-
-static void finish_ok(struct io_conn *conn, struct data *d)
-{
-	ok1(d->state == 2);
-	d->state++;
-	io_break(d);
+	return io_close(conn);
 }
 
-static void init_conn(int fd, struct data *d)
+static struct io_plan *init_conn(struct io_conn *conn, struct data *d)
 {
-	struct io_conn *conn;
-
 	ok1(d->state == 0);
 	d->state++;
 
-	conn = io_new_conn(fd, io_read(d->buf, sizeof(d->buf), no_timeout, d));
+	d->conn = conn;
 	io_set_finish(conn, finish_ok, d);
-	io_timeout(conn, time_from_usec(d->timeout_usec), timeout, d);
+
+	timer_add(&d->timers, &d->timer,
+		  timeabs_add(time_now(), time_from_usec(d->timeout_usec)));
+
+	return io_read(conn, d->buf, sizeof(d->buf), no_timeout, d);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -91,16 +85,17 @@ int main(void)
 	struct data *d = malloc(sizeof(*d));
 	struct addrinfo *addrinfo;
 	struct io_listener *l;
+	struct list_head expired;
 	int fd, status;
 
 	/* This is how many tests you plan to run */
-	plan_tests(20);
+	plan_tests(21);
 	d->state = 0;
-	d->timed_out = false;
 	d->timeout_usec = 100000;
+	timers_init(&d->timers, time_now());
 	fd = make_listen_fd(PORT, &addrinfo);
 	ok1(fd >= 0);
-	l = io_new_listener(fd, init_conn, d);
+	l = io_new_listener(NULL, fd, init_conn, d);
 	ok1(l);
 	fflush(stdout);
 
@@ -122,19 +117,31 @@ int main(void)
 		}
 		close(fd);
 		freeaddrinfo(addrinfo);
+		timers_cleanup(&d->timers);
 		free(d);
 		exit(i);
 	}
-	ok1(io_loop() == d);
-	ok1(d->state == 3);
-	ok1(d->timed_out == true);
+	ok1(io_loop(&d->timers, &expired) == NULL);
+
+	/* One element, d->timer. */
+	ok1(list_pop(&expired, struct timer, list) == &d->timer);
+	ok1(list_empty(&expired));
+	ok1(d->state == 1);
+
+	io_close(d->conn);
+
+	/* Finished will be called, d will be returned */
+	ok1(io_loop(&d->timers, &expired) == d);
+	ok1(list_empty(&expired));
+	ok1(d->state == 2);
+
+	/* It should have died. */
 	ok1(wait(&status));
 	ok1(WIFEXITED(status));
 	ok1(WEXITSTATUS(status) < sizeof(d->buf));
 
 	/* This one shouldn't time out. */
 	d->state = 0;
-	d->timed_out = false;
 	d->timeout_usec = 500000;
 	fflush(stdout);
 
@@ -156,26 +163,22 @@ int main(void)
 		}
 		close(fd);
 		freeaddrinfo(addrinfo);
+		timers_cleanup(&d->timers);
 		free(d);
 		exit(i);
 	}
-	ok1(io_loop() == d);
+	ok1(io_loop(&d->timers, &expired) == d);
 	ok1(d->state == 3);
-	ok1(d->timed_out == false);
+	ok1(list_empty(&expired));
 	ok1(wait(&status));
 	ok1(WIFEXITED(status));
 	ok1(WEXITSTATUS(status) >= sizeof(d->buf));
 
 	io_close_listener(l);
 	freeaddrinfo(addrinfo);
+	timers_cleanup(&d->timers);
 	free(d);
 
 	/* This exits depending on whether all tests passed */
 	return exit_status();
 }
-#else
-int main(void)
-{
-	return 0;
-}
-#endif
diff --git a/ccan/io/test/run-16-duplex-test.c b/ccan/io/test/run-16-duplex-test.c
index 9d939c58..ea588661 100644
--- a/ccan/io/test/run-16-duplex-test.c
+++ b/ccan/io/test/run-16-duplex-test.c
@@ -119,7 +119,7 @@ int main(void)
 		exit(0);
 	}
 	freeaddrinfo(addrinfo);
-	ok1(io_loop() == NULL);
+	ok1(io_loop(NULL, NULL) == NULL);
 	ok1(d->state == 4);
 	ok1(memcmp(d->buf, "hellothere", sizeof(d->buf)) == 0);
 	free(d);
diff --git a/ccan/io/test/run-17-homemade-io.c b/ccan/io/test/run-17-homemade-io.c
index a868b213..1087e250 100644
--- a/ccan/io/test/run-17-homemade-io.c
+++ b/ccan/io/test/run-17-homemade-io.c
@@ -166,7 +166,7 @@ int main(void)
 		exit(0);
 	}
 	freeaddrinfo(addrinfo);
-	ok1(io_loop() == pkt);
+	ok1(io_loop(NULL, NULL) == pkt);
 	ok1(pkt->state == 4);
 	ok1(pkt->len == 8);
 	ok1(memcmp(pkt->contents, "hithere!", 8) == 0);
diff --git a/ccan/io/test/run-18-errno.c b/ccan/io/test/run-18-errno.c
index f67c0eb0..c19ab375 100644
--- a/ccan/io/test/run-18-errno.c
+++ b/ccan/io/test/run-18-errno.c
@@ -109,7 +109,7 @@ int main(void)
 		exit(0);
 	}
 	freeaddrinfo(addrinfo);
-	ok1(io_loop() == &state + 1);
+	ok1(io_loop(NULL, NULL) == &state + 1);
 	ok1(state == 4);
 	io_close_listener(l);
 	ok1(wait(&state));
diff --git a/ccan/io/test/run-19-always.c b/ccan/io/test/run-19-always.c
index 24771969..63eb34e6 100644
--- a/ccan/io/test/run-19-always.c
+++ b/ccan/io/test/run-19-always.c
@@ -117,7 +117,7 @@ int main(void)
 		free(d);
 		exit(0);
 	}
-	ok1(io_loop() == d);
+	ok1(io_loop(NULL, NULL) == d);
 	ok1(d->state == 2);
 
 	ok1(wait(&status));