ccan/io: io_close_cb()

Overloading io_close() as a callback is ugly: create an explicit
io_close_cb().

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

ccan/io/_info

@@ -46,7 +46,7 @@
  * static void reader_exit(struct io_conn *c, struct stdin_buffer *b)
  * {
  * 	assert(c == b->reader);
- * 	io_wake(b->writer, io_close(b->writer, NULL));
+ * 	io_wake(b->writer, io_close());
  * 	b->reader = NULL;
  * }
  *
@@ -54,7 +54,7 @@
  * {
  * 	assert(c == b->writer);
  *	if (!b->reader)
- *		return io_close(c, NULL);
+ *		return io_close();
  *	b->len = sizeof(b->inbuf);
  * 	io_wake(b->reader, io_read_partial(b->inbuf, &b->len, wake_writer, b));
  * 	return io_idle();

ccan/io/benchmarks/run-loop.c

@@ -23,7 +23,7 @@ static struct io_plan poke_writer(struct io_conn *conn, struct buffer *buf)
 	assert(conn == buf->reader);
 
 	if (buf->iters == NUM_ITERS)
-		return io_close(conn, NULL);
+		return io_close();
 
 	/* You write. */
 	io_wake(buf->writer,
@@ -41,7 +41,7 @@ static struct io_plan poke_reader(struct io_conn *conn, struct buffer *buf)
 		io_read(&buf->buf, sizeof(buf->buf), poke_writer, buf));
 
 	if (++buf->iters == NUM_ITERS)
-		return io_close(conn, NULL);
+		return io_close();
 
 	/* I'll wait until you tell me to write. */
 	return io_idle();

ccan/io/io.c

@@ -275,8 +275,8 @@ struct io_plan io_idle(void)
 
 	plan.pollflag = 0;
 	plan.io = NULL;
-	/* Never called (overridded by io_wake), but NULL means closing */
-	plan.next = io_close;
+	/* Never called (overridden by io_wake), but NULL means closing */
+	plan.next = (void *)io_idle;
 
 	io_plan_debug(&plan);
 	return plan;
@@ -301,7 +301,7 @@ void io_ready(struct io_conn *conn)
 	switch (conn->plan.io(conn->fd.fd, &conn->plan)) {
 	case -1: /* Failure means a new plan: close up. */
 		set_current(conn);
-		conn->plan = io_close(NULL, NULL);
+		conn->plan = io_close();
 		backend_plan_changed(conn);
 		set_current(NULL);
 		break;
@@ -317,9 +317,8 @@ void io_ready(struct io_conn *conn)
 	}
 }
 
-/* Useful next functions. */
 /* Close the connection, we're done. */
-struct io_plan io_close(struct io_conn *conn, void *arg)
+struct io_plan io_close(void)
 {
 	struct io_plan plan;
 
@@ -331,6 +330,11 @@ struct io_plan io_close(struct io_conn *conn, void *arg)
 	return plan;
 }
 
+struct io_plan io_close_cb(struct io_conn *conn, void *arg)
+{
+	return io_close();
+}
+
 /* Exit the loop, returning this (non-NULL) arg. */
 struct io_plan io_break_(void *ret, struct io_plan plan)
 {

ccan/io/io.h

@@ -290,17 +290,20 @@ struct io_plan io_break_(void *ret, struct io_plan plan);
 /* FIXME: io_recvfrom/io_sendto */
 
 /**
- * io_close - terminate a connection.
- * @conn: any connection.
+ * io_close - plan to close a connection.
  *
- * The schedules a connection to be closed.  It can be done on any
- * connection, whether it has I/O queued or not (though that I/O may
- * be performed first).
+ * On return to io_loop, the connection will be closed.
+ */
+struct io_plan io_close(void);
+
+/**
+ * io_close_cb - helper callback to close a connection.
+ * @conn: the connection.
  *
- * It's common to 'return io_close(...)' from a @next function, but
- * io_close can also be used as an argument to io_next().
+ * This schedules a connection to be closed; designed to be used as
+ * a callback function.
  */
-struct io_plan io_close(struct io_conn *, void *unused);
+struct io_plan io_close_cb(struct io_conn *, void *unused);
 
 /**
  * io_loop - process fds until all closed on io_break.

ccan/io/poll.c

@@ -341,11 +341,10 @@ void *io_loop(void)
 			} else if (events & POLLHUP) {
 				r--;
 				set_current(c);
-				set_plan(c, io_close(c, NULL));
+				set_plan(c, io_close());
 				if (c->duplex) {
 					set_current(c->duplex);
-					set_plan(c->duplex,
-						 io_close(c->duplex, NULL));
+					set_plan(c->duplex, io_close());
 				}
 			}
 		}

ccan/io/test/run-01-start-finish.c

@@ -21,8 +21,7 @@ static void init_conn(int fd, int *state)
 {
 	ok1(*state == 0);
 	(*state)++;
-	io_set_finish(io_new_conn(fd, io_close(NULL, NULL)), finish_ok, state);
-
+	io_set_finish(io_new_conn(fd, io_close()), finish_ok, state);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)

ccan/io/test/run-02-read.c

@@ -28,7 +28,7 @@ static void init_conn(int fd, struct data *d)
 	d->state++;
 
 	io_set_finish(io_new_conn(fd,
-				  io_read(d->buf, sizeof(d->buf), io_close, d)),
+				  io_read(d->buf, sizeof(d->buf), io_close_cb, d)),
 		      finish_ok, d);
 }
 

ccan/io/test/run-03-readpartial.c

@@ -30,7 +30,7 @@ static void init_conn(int fd, struct data *d)
 	d->bytes = sizeof(d->buf);
 
 	io_set_finish(io_new_conn(fd,
-				  io_read_partial(d->buf, &d->bytes, io_close, d)),
+				  io_read_partial(d->buf, &d->bytes, io_close_cb, d)),
 		      finish_ok, d);
 }
 

ccan/io/test/run-04-writepartial.c

@@ -28,7 +28,7 @@ static void init_conn(int fd, struct data *d)
 	ok1(d->state == 0);
 	d->state++;
 	io_set_finish(io_new_conn(fd,
-				  io_write_partial(d->buf, &d->bytes, io_close, d)),
+				  io_write_partial(d->buf, &d->bytes, io_close_cb, d)),
 				  finish_ok, d);
 }
 

ccan/io/test/run-05-write.c

@@ -27,7 +27,8 @@ static void init_conn(int fd, struct data *d)
 {
 	ok1(d->state == 0);
 	d->state++;
-	io_set_finish(io_new_conn(fd, io_write(d->buf, d->bytes, io_close, d)),
+	io_set_finish(io_new_conn(fd, io_write(d->buf, d->bytes,
+					       io_close_cb, d)),
 		      finish_ok, d);
 }
 

ccan/io/test/run-06-idle.c

@@ -24,7 +24,7 @@ static struct io_plan read_done(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 2 || d->state == 3);
 	d->state++;
-	return io_close(conn, NULL);
+	return io_close();
 }
 
 static void finish_waker(struct io_conn *conn, struct data *d)

ccan/io/test/run-07-break.c

@@ -19,7 +19,7 @@ static struct io_plan read_done(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 1);
 	d->state++;
-	return io_close(conn, NULL);
+	return io_close();
 }
 
 static void finish_ok(struct io_conn *conn, struct data *d)

ccan/io/test/run-08-hangup-on-idle.c

@@ -12,7 +12,7 @@ static struct io_plan timeout_wakeup(struct io_conn *conn, char *buf)
 {
 	/* This kills the dummy connection. */
 	close(fds2[1]);
-	return io_read(buf, 16, io_close, NULL);
+	return io_read(buf, 16, io_close_cb, NULL);
 }
 
 int main(void)
@@ -26,12 +26,13 @@ int main(void)
 	ok1(pipe(fds) == 0);
 
 	/* Write then close. */
-	io_new_conn(fds[1], io_write("hello there world", 16, io_close, NULL));
+	io_new_conn(fds[1], io_write("hello there world", 16,
+				     io_close_cb, NULL));
 	conn = io_new_conn(fds[0], io_idle());
 
 	/* To avoid assert(num_waiting) */
 	ok1(pipe(fds2) == 0);
-	io_new_conn(fds2[0], io_read(buf, 16, io_close, NULL));
+	io_new_conn(fds2[0], io_read(buf, 16, io_close_cb, NULL));
 
 	/* After half a second, it will read. */
 	io_timeout(conn, time_from_msec(500), timeout_wakeup, buf);

ccan/io/test/run-08-read-after-hangup.c

@@ -11,8 +11,8 @@ static char inbuf[8];
 
 static struct io_plan wake_it(struct io_conn *conn, struct io_conn *reader)
 {
-	io_wake(reader, io_read(inbuf, 8, io_close, NULL));
-	return io_close(conn, NULL);
+	io_wake(reader, io_read(inbuf, 8, io_close_cb, NULL));
+	return io_close();
 }
 
 int main(void)

ccan/io/test/run-10-many.c

@@ -22,7 +22,7 @@ static struct io_plan poke_writer(struct io_conn *conn, struct buffer *buf)
 	assert(conn == buf->reader);
 
 	if (buf->iters == NUM_ITERS)
-		return io_close(conn, NULL);
+		return io_close();
 
 	/* You write. */
 	io_wake(buf->writer,
@@ -40,7 +40,7 @@ static struct io_plan poke_reader(struct io_conn *conn, struct buffer *buf)
 		io_read(&buf->buf, sizeof(buf->buf), poke_writer, buf));
 
 	if (++buf->iters == NUM_ITERS)
-		return io_close(conn, NULL);
+		return io_close();
 
 	/* I'll wait until you tell me to write. */
 	return io_idle();

ccan/io/test/run-12-bidir.c

@@ -25,7 +25,7 @@ static void finish_ok(struct io_conn *conn, struct data *d)
 static struct io_plan write_done(struct io_conn *conn, struct data *d)
 {
 	d->state++;
-	return io_close(conn, NULL);
+	return io_close();
 }
 
 static void init_conn(int fd, struct data *d)
@@ -39,7 +39,7 @@ static void init_conn(int fd, struct data *d)
 
 	memset(d->wbuf, 7, sizeof(d->wbuf));
 
-	conn = io_new_conn(fd, io_read(d->buf, sizeof(d->buf), io_close, d));
+	conn = io_new_conn(fd, io_read(d->buf, sizeof(d->buf), io_close_cb, d));
 	io_set_finish(conn, finish_ok, d);
 	conn = io_duplex(conn, io_write(d->wbuf, sizeof(d->wbuf), write_done, d));
 	ok1(conn);

ccan/io/test/run-15-timeout.c

@@ -23,7 +23,7 @@ static struct io_plan no_timeout(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 1);
 	d->state++;
-	return io_close(conn, d);
+	return io_close();
 }
 
 static struct io_plan timeout(struct io_conn *conn, struct data *d)
@@ -31,7 +31,7 @@ static struct io_plan timeout(struct io_conn *conn, struct data *d)
 	ok1(d->state == 1);
 	d->state++;
 	d->timed_out = true;
-	return io_close(conn, d);
+	return io_close();
 }
 
 static void finish_ok(struct io_conn *conn, struct data *d)

ccan/io/test/run-17-homemade-io.c

@@ -90,7 +90,7 @@ static void init_conn(int fd, struct packet *pkt)
 	ok1(pkt->state == 0);
 	pkt->state++;
 
-	io_set_finish(io_new_conn(fd, io_read_packet(pkt, io_close, pkt)),
+	io_set_finish(io_new_conn(fd, io_read_packet(pkt, io_close_cb, pkt)),
 		      finish_ok, pkt);
 }