ccan/io: remove next & finish from union.

Sure, both listener and conn need them, but for different things
(listener uses them simply to set up conn).  Putting them in the
common union was a mistake.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

ccan/io/backend.h

@@ -8,18 +8,17 @@ struct fd {
 	int fd;
 	bool listener;
 	size_t backend_info;
-
-	struct io_plan *(*next)(struct io_conn *, void *arg);
-	void *next_arg;
-
-	void (*finish)(struct io_conn *, void *arg);
-	void *finish_arg;
 };
 
 
 /* Listeners create connections. */
 struct io_listener {
 	struct fd fd;
+
+	/* These are for connections we create. */
+	struct io_plan *(*next)(struct io_conn *, void *arg);
+	void (*finish)(struct io_conn *, void *arg);
+	void *conn_arg;
 };
 
 enum io_state {
@@ -74,6 +73,12 @@ struct io_timeout {
 struct io_conn {
 	struct fd fd;
 
+	struct io_plan *(*next)(struct io_conn *, void *arg);
+	void *next_arg;
+
+	void (*finish)(struct io_conn *, void *arg);
+	void *finish_arg;
+
 	struct io_conn *duplex;
 	struct io_timeout *timeout;
 

ccan/io/io.c

@@ -25,9 +25,9 @@ struct io_listener *io_new_listener_(int fd,
 
 	l->fd.listener = true;
 	l->fd.fd = fd;
-	l->fd.next = start;
-	l->fd.finish = finish;
-	l->fd.finish_arg = l->fd.next_arg = arg;
+	l->next = start;
+	l->finish = finish;
+	l->conn_arg = arg;
 	if (!add_listener(l)) {
 		free(l);
 		return NULL;
@@ -54,9 +54,9 @@ struct io_conn *io_new_conn_(int fd,
 
 	conn->fd.listener = false;
 	conn->fd.fd = fd;
-	conn->fd.next = start;
-	conn->fd.finish = finish;
-	conn->fd.finish_arg = conn->fd.next_arg = arg;
+	conn->next = start;
+	conn->finish = finish;
+	conn->finish_arg = conn->next_arg = arg;
 	conn->pollflag = 0;
 	conn->state = NEXT;
 	conn->duplex = NULL;
@@ -83,9 +83,9 @@ struct io_conn *io_duplex_(struct io_conn *old,
 
 	conn->fd.listener = false;
 	conn->fd.fd = old->fd.fd;
-	conn->fd.next = start;
-	conn->fd.finish = finish;
-	conn->fd.finish_arg = conn->fd.next_arg = arg;
+	conn->next = start;
+	conn->finish = finish;
+	conn->finish_arg = conn->next_arg = arg;
 	conn->pollflag = 0;
 	conn->state = NEXT;
 	conn->duplex = old;
@@ -126,8 +126,8 @@ struct io_plan *io_write_(struct io_conn *conn, const void *data, size_t len,
 {
 	conn->u.write.buf = data;
 	conn->u.write.len = len;
-	conn->fd.next = cb;
-	conn->fd.next_arg = arg;
+	conn->next = cb;
+	conn->next_arg = arg;
 	conn->pollflag = POLLOUT;
 	return to_ioplan(WRITE);
 }
@@ -139,8 +139,8 @@ struct io_plan *io_read_(struct io_conn *conn, void *data, size_t len,
 {
 	conn->u.read.buf = data;
 	conn->u.read.len = len;
-	conn->fd.next = cb;
-	conn->fd.next_arg = arg;
+	conn->next = cb;
+	conn->next_arg = arg;
 	conn->pollflag = POLLIN;
 	return to_ioplan(READ);
 }
@@ -152,8 +152,8 @@ struct io_plan *io_read_partial_(struct io_conn *conn, void *data, size_t *len,
 {
 	conn->u.readpart.buf = data;
 	conn->u.readpart.lenp = len;
-	conn->fd.next = cb;
-	conn->fd.next_arg = arg;
+	conn->next = cb;
+	conn->next_arg = arg;
 	conn->pollflag = POLLIN;
 	return to_ioplan(READPART);
 }
@@ -166,8 +166,8 @@ struct io_plan *io_write_partial_(struct io_conn *conn,
 {
 	conn->u.writepart.buf = data;
 	conn->u.writepart.lenp = len;
-	conn->fd.next = cb;
-	conn->fd.next_arg = arg;
+	conn->next = cb;
+	conn->next_arg = arg;
 	conn->pollflag = POLLOUT;
 	return to_ioplan(WRITEPART);
 }
@@ -186,8 +186,8 @@ void io_wake_(struct io_conn *conn,
 	if (conn->state == FINISHED)
 		return;
 	assert(conn->state == IDLE);
-	conn->fd.next = fn;
-	conn->fd.next_arg = arg;
+	conn->next = fn;
+	conn->next_arg = arg;
 	backend_set_state(conn, to_ioplan(NEXT));
 }
 
@@ -195,7 +195,7 @@ static struct io_plan *do_next(struct io_conn *conn)
 {
 	if (timeout_active(conn))
 		backend_del_timeout(conn);
-	return conn->fd.next(conn, conn->fd.next_arg);
+	return conn->next(conn, conn->next_arg);
 }
 
 struct io_plan *do_ready(struct io_conn *conn)
@@ -259,8 +259,8 @@ struct io_plan *io_break_(struct io_conn *conn, void *ret,
 			  void *arg)
 {
 	io_loop_return = ret;
-	conn->fd.next = fn;
-	conn->fd.next_arg = arg;
+	conn->next = fn;
+	conn->next_arg = arg;
 
 	return to_ioplan(NEXT);
 }

ccan/io/poll.c

@@ -90,8 +90,8 @@ bool add_duplex(struct io_conn *c)
 
 static void del_conn(struct io_conn *conn)
 {
-	if (conn->fd.finish)
-		conn->fd.finish(conn, conn->fd.finish_arg);
+	if (conn->finish)
+		conn->finish(conn, conn->finish_arg);
 	if (timeout_active(conn))
 		backend_del_timeout(conn);
 	free(conn->timeout);
@@ -146,7 +146,7 @@ static void accept_conn(struct io_listener *l)
 	/* FIXME: What to do here? */
 	if (fd < 0)
 		return;
-	c = io_new_conn(fd, l->fd.next, l->fd.finish, l->fd.next_arg);
+	c = io_new_conn(fd, l->next, l->finish, l->conn_arg);
 	if (!c) {
 		close(fd);
 		return;
@@ -174,9 +174,7 @@ static void finish_and_next(bool finished_only)
 				free(c);
 				i--;
 			} else if (!finished_only && c->state == NEXT) {
-				backend_set_state(c,
-						  c->fd.next(c,
-							     c->fd.next_arg));
+				backend_set_state(c, c->next(c, c->next_arg));
 				num_next--;
 			}
 		}