ccan/io: rewrite.

I found it difficult to use myself, particularly io_duplex().

So this removes that, as well as timers and debug (for the moment).

API changes:
1) An io_plan is passed by pointer, rather than copied on the stack.
3) All io_plans are generated using the struct io_conn.
3) tal is the allocator.
4) A new connection must be set up with a callback, so this is now the
   same as one generated from a listener.
5) io_read_partial and io_write_partial take an explicit length.
6) io_always() and io_wait() take an explit in/out arg.
7) io_break() does not return a plan.

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

ccan/io/_info

@@ -10,12 +10,6 @@
  * (eg. read, write).  It is also possible to write custom I/O
  * plans.
  *
- * When compiled with DEBUG, control flow is changed so that rather
- * than returning to the main io_loop(), plans are executed sequentially
- * providing a backtrace showing what has occurred on that connection.
- * Which connection(s) do this depends on the user-specified io_debug
- * function.
- *
  * Example:
  * // Given tr A-Z a-z outputs tr a-z a-z
  * #include <ccan/io/io.h>
@@ -41,7 +35,7 @@
  * 	io_wake(b);
  * }
  *
- * static struct io_plan read_in(struct io_conn *c, struct buffer *b)
+ * static struct io_plan *read_in(struct io_conn *c, struct buffer *b)
  * {
  * 	// Add what we just read.
  * 	b->end += b->rlen;
@@ -55,35 +49,33 @@
  * 	if (b->start == b->end)
  * 		b->start = b->end = 0;
  *
- * 	// Read in some of the rest.
- * 	b->rlen = sizeof(b->buf) - b->end;
- *
  * 	// No room?  Wait for writer
- * 	if (b->rlen == 0)
- * 		return io_wait(b, read_in, b);
+ * 	if (b->end == sizeof(b->buf))
+ * 		return io_wait(c, b, IO_IN, read_in, b);
  *
- * 	return io_read_partial(b->buf + b->end, &b->rlen, read_in, b);
+ * 	return io_read_partial(c, b->buf + b->end, sizeof(b->buf) - b->end,
+ *			       &b->rlen, read_in, b);
  * }
  *
- * static struct io_plan write_out(struct io_conn *c, struct buffer *b)
+ * static struct io_plan *write_out(struct io_conn *c, struct buffer *b)
  * {
  * 	// Remove what we just wrote.
  * 	b->start += b->wlen;
  * 	assert(b->start <= sizeof(b->buf));
  *
- * 	// If we wrote somthing, wake writer.
+ * 	// If we wrote something, wake writer.
  * 	if (b->wlen != 0)
  * 		io_wake(b);
  *
- * 	b->wlen = b->end - b->start;
  * 	// Nothing to write?  Wait for reader.
- * 	if (b->wlen == 0) {
+ * 	if (b->end == b->start) {
  * 		if (b->finished)
- * 			return io_close();
- * 		return io_wait(b, write_out, b);
+ * 			return io_close(c);
+ * 		return io_wait(c, b, IO_OUT, write_out, b);
  * 	}
  *
- * 	return io_write_partial(b->buf + b->start, &b->wlen, write_out, b);
+ * 	return io_write_partial(c, b->buf + b->start, b->end - b->start,
+ *				&b->wlen, write_out, b);
  * }
  *
  * // Feed a program our stdin, gather its stdout, print that at end.
@@ -117,14 +109,14 @@
  *
  * 	// Read from stdin, write to child.
  * 	memset(&to, 0, sizeof(to));
- * 	reader = io_new_conn(STDIN_FILENO, read_in(NULL, &to));
+ * 	reader = io_new_conn(NULL, STDIN_FILENO, read_in, &to);
  * 	io_set_finish(reader, finish, &to);
- * 	io_new_conn(tochild[1], write_out(NULL, &to));
+ * 	io_new_conn(NULL, tochild[1], write_out, &to);
  *
  * 	// Read from child, write to stdout.
- * 	reader = io_new_conn(fromchild[0], read_in(NULL, &from));
+ * 	reader = io_new_conn(NULL, fromchild[0], read_in, &from);
  * 	io_set_finish(reader, finish, &from);
- * 	io_new_conn(STDOUT_FILENO, write_out(NULL, &from));
+ * 	io_new_conn(NULL, STDOUT_FILENO, write_out, &from);
  *
  * 	io_loop();
  * 	wait(&status);
@@ -141,9 +133,8 @@ int main(int argc, char *argv[])
 		return 1;
 
 	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/tal\n");
 		printf("ccan/typesafe_cb\n");
-		printf("ccan/time\n");
-		printf("ccan/timer\n");
 		return 0;
 	}
 

ccan/io/backend.h

@@ -2,18 +2,8 @@
 #ifndef CCAN_IO_BACKEND_H
 #define CCAN_IO_BACKEND_H
 #include <stdbool.h>
-#include <ccan/timer/timer.h>
 #include <poll.h>
-
-/* A setting for actions to always run (eg. zero-length reads). */
-#define POLLALWAYS (((POLLIN|POLLOUT) + 1) & ~((POLLIN|POLLOUT)))
-
-struct io_alloc {
-	void *(*alloc)(size_t size);
-	void *(*realloc)(void *ptr, size_t size);
-	void (*free)(void *ptr);
-};
-extern struct io_alloc io_alloc;
+#include "io_plan.h"
 
 struct fd {
 	int fd;
@@ -25,77 +15,43 @@ struct fd {
 struct io_listener {
 	struct fd fd;
 
+	const tal_t *ctx;
+
 	/* These are for connections we create. */
-	void (*init)(int fd, void *arg);
+	struct io_plan *(*init)(struct io_conn *conn, void *arg);
 	void *arg;
 };
 
-struct io_timeout {
-	struct timer timer;
-	struct io_conn *conn;
-
-	struct io_plan (*next)(struct io_conn *, void *arg);
-	void *next_arg;
-};
-
 /* One connection per client. */
 struct io_conn {
 	struct fd fd;
 
+	/* always or closing list. */
+	struct io_conn *list;
+
 	void (*finish)(struct io_conn *, void *arg);
 	void *finish_arg;
 
-	struct io_conn *duplex;
-	struct io_timeout *timeout;
-
-	struct io_plan plan;
+	struct io_plan plan[2];
 };
 
-static inline bool timeout_active(const struct io_conn *conn)
-{
-	return conn->timeout && conn->timeout->conn;
-}
-
 extern void *io_loop_return;
 
-#ifdef DEBUG
-extern struct io_conn *current;
-static inline void set_current(struct io_conn *conn)
-{
-	current = conn;
-}
-static inline bool doing_debug_on(struct io_conn *conn)
-{
-	return io_debug_conn && io_debug_conn(conn);
-}
-static inline bool doing_debug(void)
-{
-	return io_debug_conn;
-}
-#else
-static inline void set_current(struct io_conn *conn)
-{
-}
-static inline bool doing_debug_on(struct io_conn *conn)
-{
-	return false;
-}
-static inline bool doing_debug(void)
-{
-	return false;
-}
-#endif
-
 bool add_listener(struct io_listener *l);
 bool add_conn(struct io_conn *c);
 bool add_duplex(struct io_conn *c);
 void del_listener(struct io_listener *l);
-void backend_plan_changed(struct io_conn *conn);
-void backend_wait_changed(const void *wait);
-void backend_add_timeout(struct io_conn *conn, struct timerel duration);
-void backend_del_timeout(struct io_conn *conn);
+void backend_new_closing(struct io_conn *conn);
+void backend_new_always(struct io_conn *conn);
+void backend_new_plan(struct io_conn *conn);
+
+void backend_plan_done(struct io_conn *conn);
+
+void backend_wake(const void *wait);
 void backend_del_conn(struct io_conn *conn);
 
-void io_ready(struct io_conn *conn);
+void io_ready(struct io_conn *conn, int pollflags);
+void io_do_always(struct io_conn *conn);
+void io_do_wakeup(struct io_conn *conn, struct io_plan *plan);
 void *do_io_loop(struct io_conn **ready);
 #endif /* CCAN_IO_BACKEND_H */

ccan/io/io.c

@@ -13,112 +13,12 @@
 
 void *io_loop_return;
 
-struct io_alloc io_alloc = {
-	malloc, realloc, free
-};
-
-#ifdef DEBUG
-/* Set to skip the next plan. */
-bool io_plan_nodebug;
-/* The current connection to apply plan to. */
-struct io_conn *current;
-/* User-defined function to select which connection(s) to debug. */
-bool (*io_debug_conn)(struct io_conn *conn);
-
-struct io_plan io_debug(struct io_plan plan)
-{
-	struct io_conn *ready = NULL;
-
-	if (io_plan_nodebug) {
-		io_plan_nodebug = false;
-		return plan;
-	}
-
-	if (!current || !doing_debug_on(current))
-		return plan;
-
-	current->plan = plan;
-	backend_plan_changed(current);
-
-	/* Call back into the loop immediately. */
-	io_loop_return = do_io_loop(&ready);
-
-	if (ready) {
-		set_current(ready);
-		if (!ready->plan.next) {
-			/* Call finish function immediately. */
-			if (ready->finish) {
-				errno = ready->plan.u1.s;
-				ready->finish(ready, ready->finish_arg);
-				ready->finish = NULL;
-			}
-			backend_del_conn(ready);
-		} else {
-			/* Calls back in itself, via io_debug_io(). */
-			if (ready->plan.io(ready->fd.fd, &ready->plan) != 2)
-				abort();
-		}
-		set_current(NULL);
-	}
-
-	/* Return a do-nothing plan, so backend_plan_changed in
-	 * io_ready doesn't do anything (it's already been called). */
-	return io_wait_(NULL, (void *)1, NULL);
-}
-
-int io_debug_io(int ret)
-{
-	/* Cache it for debugging; current changes. */
-	struct io_conn *conn = current;
-	int saved_errno = errno;
-
-	if (!doing_debug_on(conn))
-		return ret;
-
-	/* These will all go linearly through the io_debug() path above. */
-	switch (ret) {
-	case -1:
-		/* This will call io_debug above. */
-		errno = saved_errno;
-		io_close();
-		break;
-	case 0: /* Keep going with plan. */
-		io_debug(conn->plan);
-		break;
-	case 1: /* Done: get next plan. */
-		if (timeout_active(conn))
-			backend_del_timeout(conn);
-		/* In case they call io_duplex, clear our poll flags so
-		 * both sides don't seem to be both doing read or write
-		 * (See	assert(!mask || pfd->events != mask) in poll.c) */
-		conn->plan.pollflag = 0;
-		conn->plan.next(conn, conn->plan.next_arg);
-		break;
-	default:
-		abort();
-	}
-
-	/* Normally-invalid value, used for sanity check. */
-	return 2;
-}
-
-/* Counterpart to io_plan_no_debug(), called in macros in io.h */
-static void io_plan_debug_again(void)
-{
-	io_plan_nodebug = false;
-}
-#else
-static void io_plan_debug_again(void)
-{
-}
-#endif
-
-struct io_listener *io_new_listener_(int fd,
-				     void (*init)(int fd, void *arg),
+struct io_listener *io_new_listener_(const tal_t *ctx, int fd,
+				     struct io_plan *(*init)(struct io_conn *,
+							     void *),
 				     void *arg)
 {
-	struct io_listener *l = io_alloc.alloc(sizeof(*l));
-
+	struct io_listener *l = tal(ctx, struct io_listener);
 	if (!l)
 		return NULL;
 
@@ -126,10 +26,9 @@ struct io_listener *io_new_listener_(int fd,
 	l->fd.fd = fd;
 	l->init = init;
 	l->arg = arg;
-	if (!add_listener(l)) {
-		io_alloc.free(l);
-		return NULL;
-	}
+	l->ctx = ctx;
+	if (!add_listener(l))
+		return tal_free(l);
 	return l;
 }
 
@@ -137,29 +36,60 @@ void io_close_listener(struct io_listener *l)
 {
 	close(l->fd.fd);
 	del_listener(l);
-	io_alloc.free(l);
+	tal_free(l);
 }
 
-struct io_conn *io_new_conn_(int fd, struct io_plan plan)
+static struct io_plan *io_never_called(struct io_conn *conn, void *arg)
 {
-	struct io_conn *conn = io_alloc.alloc(sizeof(*conn));
+	abort();
+}
+
+static void next_plan(struct io_conn *conn, struct io_plan *plan)
+{
+	struct io_plan *(*next)(struct io_conn *, void *arg);
+
+	next = plan->next;
 
-	io_plan_debug_again();
+	plan->status = IO_UNSET;
+	plan->io = NULL;
+	plan->next = io_never_called;
+
+	plan = next(conn, plan->next_arg);
+
+	/* It should have set a plan inside this conn. */
+	assert(plan == &conn->plan[IO_IN]
+	       || plan == &conn->plan[IO_OUT]);
+	assert(conn->plan[IO_IN].status != IO_UNSET
+	       || conn->plan[IO_OUT].status != IO_UNSET);
+
+	backend_new_plan(conn);
+}
+
+struct io_conn *io_new_conn_(const tal_t *ctx, int fd,
+			     struct io_plan *(*init)(struct io_conn *, void *),
+			     void *arg)
+{
+	struct io_conn *conn = tal(ctx, struct io_conn);
 
 	if (!conn)
 		return NULL;
 
 	conn->fd.listener = false;
 	conn->fd.fd = fd;
-	conn->plan = plan;
 	conn->finish = NULL;
 	conn->finish_arg = NULL;
-	conn->duplex = NULL;
-	conn->timeout = NULL;
-	if (!add_conn(conn)) {
-		io_alloc.free(conn);
-		return NULL;
-	}
+	conn->list = NULL;
+
+	if (!add_conn(conn))
+		return tal_free(conn);
+
+	/* We start with out doing nothing, and in doing our init. */
+	conn->plan[IO_OUT].status = IO_UNSET;
+
+	conn->plan[IO_IN].next = init;
+	conn->plan[IO_IN].next_arg = arg;
+	next_plan(conn, &conn->plan[IO_IN]);
+
 	return conn;
 }
 
@@ -171,101 +101,69 @@ void io_set_finish_(struct io_conn *conn,
 	conn->finish_arg = arg;
 }
 
-struct io_conn *io_duplex_(struct io_conn *old, struct io_plan plan)
+struct io_plan *io_get_plan(struct io_conn *conn, enum io_direction dir)
 {
-	struct io_conn *conn;
-
-	io_plan_debug_again();
+	assert(conn->plan[dir].status == IO_UNSET);
 
-	assert(!old->duplex);
-
-	conn = io_alloc.alloc(sizeof(*conn));
-	if (!conn)
-		return NULL;
-
-	conn->fd.listener = false;
-	conn->fd.fd = old->fd.fd;
-	conn->plan = plan;
-	conn->duplex = old;
-	conn->finish = NULL;
-	conn->finish_arg = NULL;
-	conn->timeout = NULL;
-	if (!add_duplex(conn)) {
-		io_alloc.free(conn);
-		return NULL;
-	}
-	old->duplex = conn;
-	return conn;
+	conn->plan[dir].status = IO_POLLING;
+	return &conn->plan[dir];
 }
 
-bool io_timeout_(struct io_conn *conn, struct timerel t,
-		 struct io_plan (*cb)(struct io_conn *, void *), void *arg)
+static struct io_plan *set_always(struct io_conn *conn,
+				  struct io_plan *plan,
+				  struct io_plan *(*next)(struct io_conn *,
+							  void *),
+				  void *arg)
 {
-	assert(cb);
-
-	if (!conn->timeout) {
-		conn->timeout = io_alloc.alloc(sizeof(*conn->timeout));
-		if (!conn->timeout)
-			return false;
-	} else
-		assert(!timeout_active(conn));
-
-	conn->timeout->next = cb;
-	conn->timeout->next_arg = arg;
-	backend_add_timeout(conn, t);
-	return true;
-}
+	plan->next = next;
+	plan->next_arg = arg;
+	plan->status = IO_ALWAYS;
 
-/* Always done: call the next thing. */
-static int do_always(int fd, struct io_plan *plan)
-{
-	return 1;
+	backend_new_always(conn);
+	return plan;
 }
 
-struct io_plan io_always_(struct io_plan (*cb)(struct io_conn *, void *),
-			  void *arg)
+struct io_plan *io_always_(struct io_conn *conn,
+			   enum io_direction dir,
+			   struct io_plan *(*next)(struct io_conn *, void *),
+			   void *arg)
 {
-	struct io_plan plan;
+	struct io_plan *plan = io_get_plan(conn, dir);
 
-	assert(cb);
-	plan.io = do_always;
-	plan.next = cb;
-	plan.next_arg = arg;
-	plan.pollflag = POLLALWAYS;
+	assert(next);
+	set_always(conn, plan, next, arg);
 
 	return plan;
 }
 
-/* Returns true if we're finished. */
 static int do_write(int fd, struct io_plan *plan)
 {
 	ssize_t ret = write(fd, plan->u1.cp, plan->u2.s);
 	if (ret < 0)
-		return io_debug_io(-1);
+		return -1;
 
 	plan->u1.cp += ret;
 	plan->u2.s -= ret;
-	return io_debug_io(plan->u2.s == 0);
+	return plan->u2.s == 0;
 }
 
 /* Queue some data to be written. */
-struct io_plan io_write_(const void *data, size_t len,
-			 struct io_plan (*cb)(struct io_conn *, void *),
-			 void *arg)
+struct io_plan *io_write_(struct io_conn *conn, const void *data, size_t len,
+			  struct io_plan *(*next)(struct io_conn *, void *),
+			  void *arg)
 {
-	struct io_plan plan;
+	struct io_plan *plan = io_get_plan(conn, IO_OUT);
 
-	assert(cb);
+	assert(next);
 
 	if (len == 0)
-		return io_always_(cb, arg);
+		return set_always(conn, plan, next, arg);
 
-	plan.u1.const_vp = data;
-	plan.u2.s = len;
-	plan.io = do_write;
-	plan.next = cb;
-	plan.next_arg = arg;
-	plan.pollflag = POLLOUT;
+	plan->u1.const_vp = data;
+	plan->u2.s = len;
+	plan->io = do_write;
+	plan->next = next;
+	plan->next_arg = arg;
 
 	return plan;
 }
@@ -274,32 +172,31 @@ static int do_read(int fd, struct io_plan *plan)
 {
 	ssize_t ret = read(fd, plan->u1.cp, plan->u2.s);
 	if (ret <= 0)
-		return io_debug_io(-1);
+		return -1;
 
 	plan->u1.cp += ret;
 	plan->u2.s -= ret;
-	return io_debug_io(plan->u2.s == 0);
+	return plan->u2.s == 0;
 }
 
 /* Queue a request to read into a buffer. */
-struct io_plan io_read_(void *data, size_t len,
-			struct io_plan (*cb)(struct io_conn *, void *),
-			void *arg)
+struct io_plan *io_read_(struct io_conn *conn,
+			 void *data, size_t len,
+			 struct io_plan *(*next)(struct io_conn *, void *),
+			 void *arg)
 {
-	struct io_plan plan;
+	struct io_plan *plan = io_get_plan(conn, IO_IN);
 
-	assert(cb);
+	assert(next);
 
 	if (len == 0)
-		return io_always_(cb, arg);
-
-	plan.u1.cp = data;
-	plan.u2.s = len;
-	plan.io = do_read;
-	plan.next = cb;
-	plan.next_arg = arg;
+		return set_always(conn, plan, next, arg);
 
-	plan.pollflag = POLLIN;
+	plan->u1.cp = data;
+	plan->u2.s = len;
+	plan->io = do_read;
+	plan->next = next;
+	plan->next_arg = arg;
 
 	return plan;
 }
@@ -308,30 +205,33 @@ static int do_read_partial(int fd, struct io_plan *plan)
 {
 	ssize_t ret = read(fd, plan->u1.cp, *(size_t *)plan->u2.vp);
 	if (ret <= 0)
-		return io_debug_io(-1);
+		return -1;
 
 	*(size_t *)plan->u2.vp = ret;
-	return io_debug_io(1);
+	return 1;
 }
 
 /* Queue a partial request to read into a buffer. */
-struct io_plan io_read_partial_(void *data, size_t *len,
-				struct io_plan (*cb)(struct io_conn *, void *),
-				void *arg)
+struct io_plan *io_read_partial_(struct io_conn *conn,
+				 void *data, size_t maxlen, size_t *len,
+				 struct io_plan *(*next)(struct io_conn *,
+							 void *),
+				 void *arg)
 {
-	struct io_plan plan;
+	struct io_plan *plan = io_get_plan(conn, IO_IN);
 
-	assert(cb);
+	assert(next);
 
-	if (*len == 0)
-		return io_always_(cb, arg);
+	if (maxlen == 0)
+		return set_always(conn, plan, next, arg);
 
-	plan.u1.cp = data;
-	plan.u2.vp = len;
-	plan.io = do_read_partial;
-	plan.next = cb;
-	plan.next_arg = arg;
-	plan.pollflag = POLLIN;
+	plan->u1.cp = data;
+	/* We store the max len in here temporarily. */
+	*len = maxlen;
+	plan->u2.vp = len;
+	plan->io = do_read_partial;
+	plan->next = next;
+	plan->next_arg = arg;
 
 	return plan;
 }
@@ -340,39 +240,37 @@ static int do_write_partial(int fd, struct io_plan *plan)
 {
 	ssize_t ret = write(fd, plan->u1.cp, *(size_t *)plan->u2.vp);
 	if (ret < 0)
-		return io_debug_io(-1);
+		return -1;
 
 	*(size_t *)plan->u2.vp = ret;
-	return io_debug_io(1);
+	return 1;
 }
 
 /* Queue a partial write request. */
-struct io_plan io_write_partial_(const void *data, size_t *len,
-				 struct io_plan (*cb)(struct io_conn*, void *),
-				 void *arg)
+struct io_plan *io_write_partial_(struct io_conn *conn,
+				  const void *data, size_t maxlen, size_t *len,
+				  struct io_plan *(*next)(struct io_conn *,
+							  void*),
+				  void *arg)
 {
-	struct io_plan plan;
+	struct io_plan *plan = io_get_plan(conn, IO_OUT);
 
-	assert(cb);
+	assert(next);
 
-	if (*len == 0)
-		return io_always_(cb, arg);
+	if (maxlen == 0)
+		return set_always(conn, plan, next, arg);
 
-	plan.u1.const_vp = data;
-	plan.u2.vp = len;
-	plan.io = do_write_partial;
-	plan.next = cb;
-	plan.next_arg = arg;
-	plan.pollflag = POLLOUT;
+	plan->u1.const_vp = data;
+	/* We store the max len in here temporarily. */
+	*len = maxlen;
+	plan->u2.vp = len;
+	plan->io = do_write_partial;
+	plan->next = next;
+	plan->next_arg = arg;
 
 	return plan;
 }
 
-static int already_connected(int fd, struct io_plan *plan)
-{
-	return io_debug_io(1);
-}
-
 static int do_connect(int fd, struct io_plan *plan)
 {
 	int err, ret;
@@ -394,143 +292,135 @@ static int do_connect(int fd, struct io_plan *plan)
 	return -1;
 }
 
-struct io_plan io_connect_(int fd, const struct addrinfo *addr,
-			   struct io_plan (*cb)(struct io_conn*, void *),
-			   void *arg)
+struct io_plan *io_connect_(struct io_conn *conn, const struct addrinfo *addr,
+			    struct io_plan *(*next)(struct io_conn *, void *),
+			    void *arg)
 {
-	struct io_plan plan;
-
-	assert(cb);
+	struct io_plan *plan = io_get_plan(conn, IO_IN);
+	int fd = io_conn_fd(conn);
 
-	plan.next = cb;
-	plan.next_arg = arg;
+	assert(next);
 
 	/* Save old flags, set nonblock if not already. */
-	plan.u1.s = fcntl(fd, F_GETFL);
-	fcntl(fd, F_SETFL, plan.u1.s | O_NONBLOCK);
+	plan->u1.s = fcntl(fd, F_GETFL);
+	fcntl(fd, F_SETFL, plan->u1.s | O_NONBLOCK);
 
 	/* Immediate connect can happen. */
-	if (connect(fd, addr->ai_addr, addr->ai_addrlen) == 0) {
-		/* Dummy will be called immediately. */
-		plan.pollflag = POLLOUT;
-		plan.io = already_connected;
-	} else {
-		if (errno != EINPROGRESS)
-			return io_close_();
-
-		plan.pollflag = POLLIN;
-		plan.io = do_connect;
-	}
+	if (connect(fd, addr->ai_addr, addr->ai_addrlen) == 0)
+		return set_always(conn, plan, next, arg);
+
+	if (errno != EINPROGRESS)
+		return io_close(conn);
+
+	plan->next = next;
+	plan->next_arg = arg;
+	plan->io = do_connect;
+
 	return plan;
 }
 
-struct io_plan io_wait_(const void *wait,
-			struct io_plan (*cb)(struct io_conn *, void*),
-			void *arg)
+struct io_plan *io_wait_(struct io_conn *conn,
+			 const void *wait, enum io_direction dir,
+			 struct io_plan *(*next)(struct io_conn *, void *),
+			 void *arg)
 {
-	struct io_plan plan;
+	struct io_plan *plan = io_get_plan(conn, dir);
 
-	assert(cb);
-	plan.pollflag = 0;
-	plan.io = NULL;
-	plan.next = cb;
-	plan.next_arg = arg;
+	assert(next);
 
-	plan.u1.const_vp = wait;
+	plan->next = next;
+	plan->next_arg = arg;
+	plan->u1.const_vp = wait;
+	plan->status = IO_WAITING;
 
 	return plan;
 }
 
 void io_wake(const void *wait)
 {
-	backend_wait_changed(wait);
+	backend_wake(wait);
 }
 
-void io_ready(struct io_conn *conn)
+static void do_plan(struct io_conn *conn, struct io_plan *plan)
 {
-	/* Beware io_close_other! */
-	if (!conn->plan.next)
+	/* Someone else might have called io_close() on us. */
+	if (plan->status == IO_CLOSING)
 		return;
 
-	set_current(conn);
-	switch (conn->plan.io(conn->fd.fd, &conn->plan)) {
-	case -1: /* Failure means a new plan: close up. */
-		conn->plan = io_close();
-		backend_plan_changed(conn);
+	/* We shouldn't have polled for this event if this wasn't true! */
+	assert(plan->status == IO_POLLING);
+
+	switch (plan->io(conn->fd.fd, plan)) {
+	case -1:
+		io_close(conn);
 		break;
-	case 0: /* Keep going with plan. */
+	case 0:
 		break;
-	case 1: /* Done: get next plan. */
-		if (timeout_active(conn))
-			backend_del_timeout(conn);
-		/* In case they call io_duplex, clear our poll flags so
-		 * both sides don't seem to be both doing read or write
-		 * (See	assert(!mask || pfd->events != mask) in poll.c) */
-		conn->plan.pollflag = 0;
-		conn->plan = conn->plan.next(conn, conn->plan.next_arg);
-		backend_plan_changed(conn);
+	case 1:
+		next_plan(conn, plan);
+		break;
+	default:
+		/* IO should only return -1, 0 or 1 */
+		abort();
 	}
-	set_current(NULL);
 }
 
-/* Close the connection, we're done. */
-struct io_plan io_close_(void)
+void io_ready(struct io_conn *conn, int pollflags)
 {
-	struct io_plan plan;
-
-	plan.pollflag = 0;
-	/* This means we're closing. */
-	plan.next = NULL;
-	plan.u1.s = errno;
+	if (pollflags & POLLIN)
+		do_plan(conn, &conn->plan[IO_IN]);
 
-	return plan;
+	if (pollflags & POLLOUT)
+		do_plan(conn, &conn->plan[IO_OUT]);
 }
 
-struct io_plan io_close_cb(struct io_conn *conn, void *arg)
+void io_do_always(struct io_conn *conn)
 {
-	return io_close();
+	if (conn->plan[IO_IN].status == IO_ALWAYS)
+		next_plan(conn, &conn->plan[IO_IN]);
+
+	if (conn->plan[IO_OUT].status == IO_ALWAYS)
+		next_plan(conn, &conn->plan[IO_OUT]);
 }
 
-void io_close_other(struct io_conn *conn)
+void io_do_wakeup(struct io_conn *conn, struct io_plan *plan)
 {
-	/* Don't close if already closing! */
-	if (conn->plan.next) {
-		conn->plan = io_close_();
-		backend_plan_changed(conn);
-	}
+	assert(plan->status == IO_WAITING);
+	next_plan(conn, plan);
 }
 
-/* Exit the loop, returning this (non-NULL) arg. */
-struct io_plan io_break_(void *ret, struct io_plan plan)
+/* Close the connection, we're done. */
+struct io_plan *io_close(struct io_conn *conn)
 {
-	io_plan_debug_again();
+	/* Already closing?  Don't close twice. */
+	if (conn->plan[IO_IN].status == IO_CLOSING)
+		return &conn->plan[IO_IN];
 
-	assert(ret);
-	io_loop_return = ret;
+	conn->plan[IO_IN].status = conn->plan[IO_OUT].status = IO_CLOSING;
+	conn->plan[IO_IN].u1.s = errno;
+	backend_new_closing(conn);
 
-	return plan;
+	return &conn->plan[IO_IN];
 }
 
-static struct io_plan io_never_called(struct io_conn *conn, void *arg)
+struct io_plan *io_close_cb(struct io_conn *conn, void *arg)
 {
-	abort();
+	return io_close(conn);
 }
 
-struct io_plan io_never(void)
+/* Exit the loop, returning this (non-NULL) arg. */
+void io_break(const void *ret)
 {
-	return io_always_(io_never_called, NULL);
+	assert(ret);
+	io_loop_return = (void *)ret;
 }
 
-int io_conn_fd(const struct io_conn *conn)
+struct io_plan *io_never(struct io_conn *conn)
 {
-	return conn->fd.fd;
+	return io_always(conn, IO_IN, io_never_called, NULL);
 }
 
-void io_set_alloc(void *(*allocfn)(size_t size),
-		  void *(*reallocfn)(void *ptr, size_t size),
-		  void (*freefn)(void *ptr))
+int io_conn_fd(const struct io_conn *conn)
 {
-	io_alloc.alloc = allocfn;
-	io_alloc.realloc = reallocfn;
-	io_alloc.free = freefn;
+	return conn->fd.fd;
 }

ccan/io/io.h

@@ -1,35 +1,69 @@
 /* Licensed under LGPLv2.1+ - see LICENSE file for details */
 #ifndef CCAN_IO_H
 #define CCAN_IO_H
+#include <ccan/tal/tal.h>
 #include <ccan/typesafe_cb/typesafe_cb.h>
-#include <ccan/time/time.h>
 #include <stdbool.h>
 #include <unistd.h>
-#include "io_plan.h"
+
+enum io_direction {
+	IO_IN,
+	IO_OUT
+};
+
+/**
+ * struct io_plan - a plan for input or output.
+ *
+ * Each io_conn has zero to two of these active at any time.
+ */
+struct io_plan;
+
+/**
+ * struct io_conn - a connection associated with an fd.
+ */
+struct io_conn;
 
 /**
  * io_new_conn - create a new connection.
+ * @ctx: the context to tal from (or NULL)
  * @fd: the file descriptor.
- * @plan: the first I/O to perform.
+ * @init: the function to call for a new connection
+ * @arg: the argument to @init.
  *
- * This creates a connection which owns @fd.  @plan will be called on the
- * next io_loop().
+ * This creates a connection which owns @fd, it then calls
+ * @init to initialize the connection, which sets up an io_plan.
  *
  * Returns NULL on error (and sets errno).
  *
  * Example:
+ * // Dumb init function to print string and tell conn to close.
+ * static struct io_plan *conn_init(struct io_conn *conn, const char *msg)
+ * {
+ *	printf("Created conn %p: %s", conn, msg);
+ *	return io_close(conn);
+ * }
+ *
+ * static void create_self_closing_pipe(void)
+ * {
  *	int fd[2];
  *	struct io_conn *conn;
  *
  *	pipe(fd);
- *	// Plan is to close the fd immediately.
- *	conn = io_new_conn(fd[0], io_close());
+ *	conn = io_new_conn(NULL, fd[0], conn_init, (const char *)"hi!");
  *	if (!conn)
  *		exit(1);
+ * }
  */
-#define io_new_conn(fd, plan)				\
-	(io_plan_no_debug(), io_new_conn_((fd), (plan)))
-struct io_conn *io_new_conn_(int fd, struct io_plan plan);
+#define io_new_conn(ctx, fd, init, arg)					\
+	io_new_conn_((ctx), (fd),					\
+		     typesafe_cb_preargs(struct io_plan *, void *,	\
+					 (init), (arg),			\
+					 struct io_conn *conn),		\
+		     (void *)(arg))
+
+struct io_conn *io_new_conn_(const tal_t *ctx, int fd,
+			     struct io_plan *(*init)(struct io_conn *, void *),
+			     void *arg);
 
 /**
  * io_set_finish - set finish function on a connection.
@@ -40,34 +74,42 @@ struct io_conn *io_new_conn_(int fd, struct io_plan plan);
  * @finish will be called when an I/O operation fails, or you call
  * io_close() on the connection.  errno will be set to the value
  * after the failed I/O, or at the call to io_close().  The fd
- * will be closed (unless a duplex) before @finish is called.
+ * will be closed before @finish is called.
  *
  * Example:
- * static void finish(struct io_conn *conn, void *unused)
+ * static void finish(struct io_conn *conn, const char *msg)
  * {
  *	// errno is not 0 after success, so this is a bit useless.
- *	printf("Conn %p closed with errno %i\n", conn, errno);
+ *	printf("Conn %p closed with errno %i (%s)\n", conn, errno, msg);
+ * }
+ *
+ * // Dumb init function to print string and tell conn to close.
+ * static struct io_plan *conn_init(struct io_conn *conn, const char *msg)
+ * {
+ *	io_set_finish(conn, finish, msg);
+ *	return io_close(conn);
  * }
- * ...
- *	io_set_finish(conn, finish, NULL);
  */
 #define io_set_finish(conn, finish, arg)				\
 	io_set_finish_((conn),						\
 		       typesafe_cb_preargs(void, void *,		\
 					   (finish), (arg),		\
 					   struct io_conn *),		\
-		       (arg))
+		       (void *)(arg))
 void io_set_finish_(struct io_conn *conn,
 		    void (*finish)(struct io_conn *, void *),
 		    void *arg);
 
+
 /**
  * io_new_listener - create a new accepting listener.
+ * @ctx: the context to tal from (or NULL)
  * @fd: the file descriptor.
  * @init: the function to call for a new connection
  * @arg: the argument to @init.
  *
- * When @fd becomes readable, we accept() and pass that fd to init().
+ * When @fd becomes readable, we accept(), create a new connection,
+ * (tal'ocated off @ctx) and pass that to init().
  *
  * Returns NULL on error (and sets errno).
  *
@@ -76,11 +118,7 @@ void io_set_finish_(struct io_conn *conn,
  * #include <sys/socket.h>
  * #include <netdb.h>
  *
- * static void start_conn(int fd, char *msg)
- * {
- *	printf("%s fd %i\n", msg, fd);
- *	close(fd);
- * }
+ * ...
  *
  * // Set up a listening socket, return it.
  * static struct io_listener *do_listen(const char *port)
@@ -112,17 +150,18 @@ void io_set_finish_(struct io_conn *conn,
  *		close(fd);
  *		return NULL;
  *	}
- *	return io_new_listener(fd, start_conn, (char *)"Got one!");
+ *	return io_new_listener(NULL, fd, conn_init, (const char *)"listened!");
  * }
  */
-#define io_new_listener(fd, init, arg)					\
-	io_new_listener_((fd),						\
-			 typesafe_cb_preargs(void, void *,		\
+#define io_new_listener(ctx, fd, init, arg)				\
+	io_new_listener_((ctx), (fd),					\
+			 typesafe_cb_preargs(struct io_plan *, void *,	\
 					     (init), (arg),		\
-					     int fd),			\
-			 (arg))
-struct io_listener *io_new_listener_(int fd,
-				     void (*init)(int fd, void *arg),
+					     struct io_conn *conn),	\
+			 (void *)(arg))
+struct io_listener *io_new_listener_(const tal_t *ctx, int fd,
+				     struct io_plan *(*init)(struct io_conn *,
+							     void *),
 				     void *arg);
 
 /**
@@ -142,73 +181,79 @@ struct io_listener *io_new_listener_(int fd,
 void io_close_listener(struct io_listener *listener);
 
 /**
- * io_write - plan to write data.
+ * io_write - output plan to write data.
+ * @conn: the connection that plan is for.
  * @data: the data buffer.
  * @len: the length to write.
- * @cb: function to call once it's done.
- * @arg: @cb argument
+ * @next: function to call output is done.
+ * @arg: @next argument
  *
- * This creates a plan write out a data buffer.  Once it's all
- * written, the @cb function will be called: on an error, the finish
+ * This updates the output plan, to write out a data buffer.  Once it's all
+ * written, the @next function will be called: on an error, the finish
  * function is called instead.
  *
  * Note that the I/O may actually be done immediately.
  *
  * Example:
- * static void start_conn_with_write(int fd, const char *msg)
+ * static struct io_plan *write_to_conn(struct io_conn *conn, const char *msg)
  * {
  *	// Write message, then close.
- *	io_new_conn(fd, io_write(msg, strlen(msg), io_close_cb, NULL));
+ *	return io_write(conn, msg, strlen(msg), io_close_cb, NULL);
  * }
  */
-#define io_write(data, len, cb, arg)					\
-	io_debug(io_write_((data), (len),				\
-			   typesafe_cb_preargs(struct io_plan, void *,	\
-					       (cb), (arg), struct io_conn *), \
-			   (arg)))
-struct io_plan io_write_(const void *data, size_t len,
-			 struct io_plan (*cb)(struct io_conn *, void *),
-			 void *arg);
+#define io_write(conn, data, len, next, arg)				\
+	io_write_((conn), (data), (len),				\
+		  typesafe_cb_preargs(struct io_plan *, void *,		\
+				      (next), (arg), struct io_conn *),	\
+		  (arg))
+struct io_plan *io_write_(struct io_conn *conn,
+			  const void *data, size_t len,
+			  struct io_plan *(*next)(struct io_conn *, void *),
+			  void *arg);
 
 /**
- * io_read - plan to read data.
+ * io_read - input plan to read data.
+ * @conn: the connection that plan is for.
  * @data: the data buffer.
  * @len: the length to read.
- * @cb: function to call once it's done.
- * @arg: @cb argument
+ * @next: function to call once input is done.
+ * @arg: @next argument
  *
  * This creates a plan to read data into a buffer.  Once it's all
- * read, the @cb function will be called: on an error, the finish
+ * read, the @next function will be called: on an error, the finish
  * function is called instead.
  *
  * Note that the I/O may actually be done immediately.
  *
  * Example:
- * static void start_conn_with_read(int fd, char msg[12])
+ * static struct io_plan *read_from_conn(struct io_conn *conn, char *buf)
  * {
  *	// Read message, then close.
- *	io_new_conn(fd, io_read(msg, 12, io_close_cb, NULL));
+ *	return io_read(conn, buf, 12, io_close_cb, NULL);
  * }
  */
-#define io_read(data, len, cb, arg)					\
-	io_debug(io_read_((data), (len),				\
-			  typesafe_cb_preargs(struct io_plan, void *,	\
-					      (cb), (arg), struct io_conn *), \
-			  (arg)))
-struct io_plan io_read_(void *data, size_t len,
-			struct io_plan (*cb)(struct io_conn *, void *),
-			void *arg);
+#define io_read(conn, data, len, next, arg)				\
+	io_read_((conn), (data), (len),					\
+		 typesafe_cb_preargs(struct io_plan *, void *,		\
+				     (next), (arg), struct io_conn *),	\
+		 (arg))
+struct io_plan *io_read_(struct io_conn *conn,
+			 void *data, size_t len,
+			 struct io_plan *(*next)(struct io_conn *, void *),
+			 void *arg);
 
 
 /**
- * io_read_partial - plan to read some data.
+ * io_read_partial - input plan to read some data.
+ * @conn: the connection that plan is for.
  * @data: the data buffer.
- * @len: the maximum length to read, set to the length actually read.
- * @cb: function to call once it's done.
- * @arg: @cb argument
+ * @maxlen: the maximum length to read
+ * @lenp: set to the length actually read.
+ * @next: function to call once input is done.
+ * @arg: @next argument
  *
  * This creates a plan to read data into a buffer.  Once any data is
- * read, @len is updated and the @cb function will be called: on an
+ * read, @len is updated and the @next function will be called: on an
  * error, the finish function is called instead.
  *
  * Note that the I/O may actually be done immediately.
@@ -219,41 +264,42 @@ struct io_plan io_read_(void *data, size_t len,
  *	char buf[12];
  * };
  *
- * static struct io_plan dump_and_close(struct io_conn *conn, struct buf *b)
+ * static struct io_plan *dump(struct io_conn *conn, struct buf *b)
  * {
  *	printf("Partial read: '%*s'\n", (int)b->len, b->buf);
  *	free(b);
- *	return io_close();
+ *	return io_close(conn);
  * }
  *
- * static void start_conn_with_part_read(int fd, void *unused)
+ * static struct io_plan *read_part(struct io_conn *conn, struct buf *b)
  * {
- *	struct buf *b = malloc(sizeof(*b));
- *
  *	// Read message, then dump and close.
- *	b->len = sizeof(b->buf);
- *	io_new_conn(fd, io_read_partial(b->buf, &b->len, dump_and_close, b));
+ *	return io_read_partial(conn, b->buf, sizeof(b->buf), &b->len, dump, b);
  * }
  */
-#define io_read_partial(data, len, cb, arg)				\
-	io_debug(io_read_partial_((data), (len),			\
-				  typesafe_cb_preargs(struct io_plan, void *, \
-						      (cb), (arg),	\
-						      struct io_conn *), \
-				  (arg)))
-struct io_plan io_read_partial_(void *data, size_t *len,
-				struct io_plan (*cb)(struct io_conn *, void *),
-				void *arg);
+#define io_read_partial(conn, data, maxlen, lenp, next, arg)		\
+	io_read_partial_((conn), (data), (maxlen), (lenp),		\
+			 typesafe_cb_preargs(struct io_plan *, void *,	\
+					     (next), (arg),		\
+					     struct io_conn *),		\
+			 (arg))
+struct io_plan *io_read_partial_(struct io_conn *conn,
+				 void *data, size_t maxlen, size_t *lenp,
+				 struct io_plan *(*next)(struct io_conn *,
+							 void *),
+				 void *arg);
 
 /**
- * io_write_partial - plan to write some data.
+ * io_write_partial - output plan to write some data.
+ * @conn: the connection that plan is for.
  * @data: the data buffer.
- * @len: the maximum length to write, set to the length actually written.
- * @cb: function to call once it's done.
- * @arg: @cb argument
+ * @maxlen: the maximum length to write
+ * @lenp: set to the length actually written.
+ * @next: function to call once output is done.
+ * @arg: @next argument
  *
  * This creates a plan to write data from a buffer.   Once any data is
- * written, @len is updated and the @cb function will be called: on an
+ * written, @len is updated and the @next function will be called: on an
  * error, the finish function is called instead.
  *
  * Note that the I/O may actually be done immediately.
@@ -264,70 +310,71 @@ struct io_plan io_read_partial_(void *data, size_t *len,
  *	char buf[12];
  * };
  *
- * static struct io_plan show_remainder(struct io_conn *conn, struct buf *b)
+ * static struct io_plan *show_partial(struct io_conn *conn, struct buf *b)
  * {
  *	printf("Only wrote: '%*s'\n", (int)b->len, b->buf);
  *	free(b);
- *	return io_close();
+ *	return io_close(conn);
  * }
  *
- * static void start_conn_with_part_read(int fd, void *unused)
+ * static struct io_plan *write_part(struct io_conn *conn, struct buf *b)
  * {
- *	struct buf *b = malloc(sizeof(*b));
- *
  *	// Write message, then dump and close.
- *	b->len = sizeof(b->buf);
  *	strcpy(b->buf, "Hello world");
- *	io_new_conn(fd, io_write_partial(b->buf, &b->len, show_remainder, b));
+ *	return io_write_partial(conn, b->buf, strlen(b->buf),
+ *				&b->len, show_partial, b);
  * }
  */
-#define io_write_partial(data, len, cb, arg)				\
-	io_debug(io_write_partial_((data), (len),			\
-				   typesafe_cb_preargs(struct io_plan, void *, \
-						       (cb), (arg),	\
-						       struct io_conn *), \
-				   (arg)))
-struct io_plan io_write_partial_(const void *data, size_t *len,
-				 struct io_plan (*cb)(struct io_conn *, void*),
-				 void *arg);
+#define io_write_partial(conn, data, maxlen, lenp, next, arg)		\
+	io_write_partial_((conn), (data), (maxlen), (lenp),		\
+			  typesafe_cb_preargs(struct io_plan *, void *,	\
+					      (next), (arg),		\
+					      struct io_conn *),	\
+			  (arg))
+struct io_plan *io_write_partial_(struct io_conn *conn,
+				  const void *data, size_t maxlen, size_t *lenp,
+				  struct io_plan *(*next)(struct io_conn *,
+							  void*),
+				  void *arg);
 
 /**
- * io_always - plan to immediately call next callback.
- * @cb: function to call.
- * @arg: @cb argument
+ * io_always - plan to immediately call next callback
+ * @conn: the connection that plan is for.
+ * @dir: IO_IN or IO_OUT
+ * @next: function to call.
+ * @arg: @next argument
  *
  * Sometimes it's neater to plan a callback rather than call it directly;
  * for example, if you only need to read data for one path and not another.
  *
  * Example:
- * static void start_conn_with_nothing(int fd)
+ * static struct io_plan *init_conn_with_nothing(struct io_conn *conn,
+ *						 void *unused)
  * {
  *	// Silly example: close on next time around loop.
- *	io_new_conn(fd, io_always(io_close_cb, NULL));
+ *	return io_always(conn, IO_IN, io_close_cb, NULL);
  * }
  */
-#define io_always(cb, arg)						\
-	io_debug(io_always_(typesafe_cb_preargs(struct io_plan, void *,	\
-						(cb), (arg),		\
-						struct io_conn *),	\
-			    (arg)))
-struct io_plan io_always_(struct io_plan (*cb)(struct io_conn *, void *),
-			  void *arg);
+#define io_always(conn, dir, next, arg)					\
+	io_always_((conn), dir, typesafe_cb_preargs(struct io_plan *, void *, \
+						    (next), (arg),	\
+						    struct io_conn *),	\
+		   (arg))
 
+struct io_plan *io_always_(struct io_conn *conn, enum io_direction dir,
+			   struct io_plan *(*next)(struct io_conn *, void *),
+			   void *arg);
 
 /**
- * io_connect - plan to connect to a listening socket.
- * @fd: file descriptor.
+ * io_connect - create an asynchronous connection to a listening socket.
+ * @conn: the connection that plan is for.
  * @addr: where to connect.
- * @cb: function to call once it's done.
- * @arg: @cb argument
+ * @init: function to call once it's connected
+ * @arg: @init argument
  *
  * This initiates a connection, and creates a plan for
- * (asynchronously).  completing it.  Once complete, @len is updated
- * and the @cb function will be called: on an error, the finish
- * function is called instead.
- *
- * Note that the connect may actually be done immediately.
+ * (asynchronously) completing it.  Once complete, the @init function
+ * will be called.
  *
  * Example:
  * #include <sys/types.h>
@@ -335,9 +382,10 @@ struct io_plan io_always_(struct io_plan (*cb)(struct io_conn *, void *),
  * #include <netdb.h>
  *
  * // Write, then close socket.
- * static struct io_plan start_write(struct io_conn *conn, void *unused)
+ * static struct io_plan *init_connect(struct io_conn *conn,
+ *				       struct addrinfo *addrinfo)
  * {
- *	return io_write("hello", 5, io_close_cb, NULL);
+ *	return io_connect(conn, addrinfo, io_close_cb, NULL);
  * }
  *
  * ...
@@ -347,177 +395,123 @@ struct io_plan io_always_(struct io_plan (*cb)(struct io_conn *, void *),
  *
  *	fd = socket(AF_INET, SOCK_STREAM, 0);
  *	getaddrinfo("localhost", "8111", NULL, &addrinfo);
- *	io_new_conn(fd, io_connect(fd, addrinfo, start_write, NULL));
+ *	io_new_conn(NULL, fd, init_connect, addrinfo);
  */
 struct addrinfo;
-#define io_connect(fd, addr, cb, arg)					\
-	io_debug(io_connect_((fd), (addr),				\
-			     typesafe_cb_preargs(struct io_plan, void *, \
-						 (cb), (arg),		\
-						 struct io_conn *),	\
-			     (arg)))
-struct io_plan io_connect_(int fd, const struct addrinfo *addr,
-			   struct io_plan (*cb)(struct io_conn *, void*),
-			   void *arg);
-
-/**
- * io_wait - plan to wait for something.
- * @wait: the address to wait on.
- * @cb: function to call after waiting.
- * @arg: @cb argument
- *
- * This indicates the connection is idle: io_wake() will be called later to
- * restart the connection.
- *
- * Example:
- *	struct io_conn *sleeper;
- *	unsigned int counter = 0;
- *	sleeper = io_new_conn(open("/dev/null", O_RDONLY),
- *			      io_wait(&counter, io_close_cb, NULL));
- *	if (!sleeper)
- *		exit(1);
- */
-#define io_wait(wait, cb, arg)						\
-	io_debug(io_wait_(wait,						\
-			  typesafe_cb_preargs(struct io_plan, void *,	\
-					      (cb), (arg),		\
-					      struct io_conn *),	\
-			  (arg)))
-
-struct io_plan io_wait_(const void *wait,
-			struct io_plan (*cb)(struct io_conn *, void *),
-			void *arg);
-
-/**
- * io_timeout - set timeout function if the callback doesn't complete.
- * @conn: the current connection.
- * @t: how long until the timeout should be called.
- * @cb: callback to call.
- * @arg: argument to @cb.
- *
- * If the usual next callback is not called for this connection before @ts,
- * this function will be called.  If next callback is called, the timeout
- * is automatically removed.
- *
- * Returns false on allocation failure.  A connection can only have one
- * timeout.
- *
- * Example:
- *	static struct io_plan close_on_timeout(struct io_conn *conn, char *msg)
- *	{
- *		printf("%s\n", msg);
- *		return io_close();
- *	}
- *
- *	...
- *	io_timeout(sleeper, time_from_msec(100),
- *		   close_on_timeout, (char *)"Bye!");
- */
-#define io_timeout(conn, ts, fn, arg)					\
-	io_timeout_((conn), (ts),					\
-		    typesafe_cb_preargs(struct io_plan, void *,		\
-					(fn), (arg),			\
+#define io_connect(conn, addr, next, arg)				\
+	io_connect_((conn), (addr),					\
+		    typesafe_cb_preargs(struct io_plan *, void *,	\
+					(next), (arg),			\
 					struct io_conn *),		\
 		    (arg))
-bool io_timeout_(struct io_conn *conn, struct timerel t,
-		 struct io_plan (*fn)(struct io_conn *, void *), void *arg);
+
+struct io_plan *io_connect_(struct io_conn *conn, const struct addrinfo *addr,
+			    struct io_plan *(*next)(struct io_conn *, void *),
+			    void *arg);
 
 /**
- * io_duplex - split an fd into two connections.
- * @conn: a connection.
- * @plan: the first I/O function to call.
- *
- * Sometimes you want to be able to simultaneously read and write on a
- * single fd, but io forces a linear call sequence.  The solution is
- * to have two connections for the same fd, and use one for read
- * operations and one for write.
+ * io_wait - leave a plan idle until something wakes us.
+ * @conn: the connection that plan is for.
+ * @waitaddr: the address to wait on.
+ * @dir: IO_IN or IO_OUT
+ * @next: function to call after waiting.
+ * @arg: @next argument
  *
- * You must io_close() both of them to close the fd.
+ * This leaves the input or output idle: io_wake(@waitaddr) will be
+ * called later to restart the connection.
  *
  * Example:
- *	static void setup_read_write(int fd,
- *				     char greet_in[5], const char greet_out[5])
- *	{
- *		struct io_conn *writer, *reader;
- *
- *		// Read their greeting and send ours at the same time.
- *		writer = io_new_conn(fd,
- *				     io_write(greet_out, 5, io_close_cb, NULL));
- *		reader = io_duplex(writer,
- *				     io_read(greet_in, 5, io_close_cb, NULL));
- *		if (!reader || !writer)
- *			exit(1);
- *	}
+ * // Silly example to wait then close.
+ * static struct io_plan *wait(struct io_conn *conn, void *b)
+ * {
+ *	return io_wait(conn, b, IO_IN, io_close_cb, NULL);
+ * }
  */
-#define io_duplex(conn, plan)				\
-	(io_plan_no_debug(), io_duplex_((conn), (plan)))
-struct io_conn *io_duplex_(struct io_conn *conn, struct io_plan plan);
+#define io_wait(conn, waitaddr, dir, next, arg)				\
+	io_wait_((conn), (waitaddr), (dir),				\
+		 typesafe_cb_preargs(struct io_plan *, void *,		\
+				     (next), (arg),			\
+				     struct io_conn *),			\
+		 (arg))
+
+struct io_plan *io_wait_(struct io_conn *conn,
+			 const void *wait, enum io_direction dir,
+			 struct io_plan *(*next)(struct io_conn *, void *),
+			 void *arg);
+
 
 /**
  * io_wake - wake up any connections waiting on @wait
- * @wait: the address to trigger.
- *
- * Example:
- *	unsigned int wait;
+ * @waitaddr: the address to trigger.
  *
- *	io_new_conn(open("/dev/null", O_RDONLY),
- *		   io_wait(&wait, io_close_cb, NULL));
+ * All io_conns who have returned io_wait() on @waitaddr will move on
+ * to their next callback.
  *
- *	io_wake(&wait);
+ * Example:
+ * static struct io_plan *wake_it(struct io_conn *conn, void *b)
+ * {
+ *	io_wake(b);
+ *	return io_close(conn);
+ * }
  */
 void io_wake(const void *wait);
 
 /**
  * io_break - return from io_loop()
  * @ret: non-NULL value to return from io_loop().
- * @plan: I/O to perform on return (if any)
  *
- * This breaks out of the io_loop.  As soon as the current @next
- * function returns, any io_closed()'d connections will have their
- * finish callbacks called, then io_loop() with return with @ret.
+ * This breaks out of the io_loop.  As soon as the current function
+ * returns, any io_close()'d connections will have their finish
+ * callbacks called, then io_loop() with return with @ret.
  *
  * If io_loop() is called again, then @plan will be carried out.
  *
  * Example:
- *	static struct io_plan fail_on_timeout(struct io_conn *conn, char *msg)
+ *	static struct io_plan *fail_on_timeout(struct io_conn *conn, char *msg)
  *	{
- *		return io_break(msg, io_close());
+ *		io_break(msg);
+ *		return io_close(conn);
  *	}
  */
-#define io_break(ret, plan) (io_plan_no_debug(), io_break_((ret), (plan)))
-struct io_plan io_break_(void *ret, struct io_plan plan);
+void io_break(const void *ret);
 
 /**
  * io_never - assert if callback is called.
+ * @conn: the connection that plan is for.
  *
  * Sometimes you want to make it clear that a callback should never happen
  * (eg. for io_break).  This will assert() if called.
  *
  * Example:
- * static struct io_plan break_out(struct io_conn *conn, void *unused)
+ * static struct io_plan *break_out(struct io_conn *conn, void *unused)
  * {
+ *	io_break(conn);
  *	// We won't ever return from io_break
- *	return io_break(conn, io_never());
+ *	return io_never(conn);
  * }
  */
-struct io_plan io_never(void);
+struct io_plan *io_never(struct io_conn *conn);
 
 /* FIXME: io_recvfrom/io_sendto */
 
 /**
  * io_close - plan to close a connection.
+ * @conn: the connection to close.
+ *
+ * On return to io_loop, the connection will be closed.  It doesn't have
+ * to be the current connection and it doesn't need to be idle.  No more
+ * IO or callbacks will occur.
  *
- * On return to io_loop, the connection will be closed.
+ * You can close a connection twice without harmful effects.
  *
  * Example:
- * static struct io_plan close_on_timeout(struct io_conn *conn, const char *msg)
+ * static struct io_plan *close_on_timeout(struct io_conn *conn, const char *msg)
  * {
  *	printf("closing: %s\n", msg);
- *	return io_close();
+ *	return io_close(conn);
  * }
  */
-#define io_close() io_debug(io_close_())
-struct io_plan io_close_(void);
+struct io_plan *io_close(struct io_conn *conn);
 
 /**
  * io_close_cb - helper callback to close a connection.
@@ -529,25 +523,7 @@ struct io_plan io_close_(void);
  * Example:
  *	#define close_on_timeout io_close_cb
  */
-struct io_plan io_close_cb(struct io_conn *, void *unused);
-
-/**
- * io_close_other - close different connection next time around the I/O loop.
- * @conn: the connection to close.
- *
- * This is used to force a different connection to close: no more I/O will
- * happen on @conn, even if it's pending.
- *
- * It's a bug to use this on the current connection!
- *
- * Example:
- * static void stop_connection(struct io_conn *conn)
- * {
- *	printf("forcing stop on connection\n");
- *	io_close_other(conn);
- * }
- */
-void io_close_other(struct io_conn *conn);
+struct io_plan *io_close_cb(struct io_conn *, void *unused);
 
 /**
  * io_loop - process fds until all closed on io_break.
@@ -567,17 +543,4 @@ void *io_loop(void);
  * Sometimes useful, eg for getsockname().
  */
 int io_conn_fd(const struct io_conn *conn);
-
-/**
- * io_set_alloc - set alloc/realloc/free function for io to use.
- * @allocfn: allocator function
- * @reallocfn: reallocator function, ptr may be NULL, size never 0.
- * @freefn: free function
- *
- * By default io uses malloc/realloc/free, and returns NULL if they fail.
- * You can set your own variants here.
- */
-void io_set_alloc(void *(*allocfn)(size_t size),
-		  void *(*reallocfn)(void *ptr, size_t size),
-		  void (*freefn)(void *ptr));
 #endif /* CCAN_IO_H */

ccan/io/io_plan.h

@@ -4,129 +4,50 @@
 struct io_conn;
 
 /**
- * struct io_plan - a plan of what I/O to do.
- * @pollflag: POLLIN or POLLOUT.
- * @io: function to call when fd is available for @pollflag.
- * @next: function to call after @io returns true.
- * @next_arg: argument to @next.
- * @u1: scratch area for I/O.
- * @u2: scratch area for I/O.
- *
- * When the fd is POLLIN or POLLOUT (according to @pollflag), @io is
- * called.  If it returns -1, io_close() becomed the new plan (and errno
- * is saved).  If it returns 1, @next is called, otherwise @io is
- * called again when @pollflag is available.
- *
- * You can use this to write your own io_plan functions.
+ * union io_plan_arg - scratch space for struct io_plan read/write fns.
  */
-struct io_plan {
-	int pollflag;
-	/* Only NULL if idle. */
-	int (*io)(int fd, struct io_plan *plan);
-	/* Only NULL if closing. */
-	struct io_plan (*next)(struct io_conn *, void *arg);
-	void *next_arg;
+union io_plan_arg {
+	char *cp;
+	void *vp;
+	const void *const_vp;
+	size_t s;
+	char c[sizeof(size_t)];
+};
 
-	union {
-		char *cp;
-		void *vp;
-		const void *const_vp;
-		size_t s;
-		char c[sizeof(size_t)];
-	} u1;
-	union {
-		char *p;
-		void *vp;
-		const void *const_vp;
-		size_t s;
-		char c[sizeof(size_t)];
-	} u2;
+enum io_plan_status {
+	/* As before calling next function. */
+	IO_UNSET,
+	/* Normal. */
+	IO_POLLING,
+	/* Waiting for io_wake */
+	IO_WAITING,
+	/* Always do this. */
+	IO_ALWAYS,
+	/* Closing (both plans will be the same). */
+	IO_CLOSING
 };
 
-#ifdef DEBUG
 /**
- * io_debug_conn - routine to select connection(s) to debug.
- *
- * If this is set, the routine should return true if the connection is a
- * debugging candidate.  If so, the callchain for I/O operations on this
- * connection will be linear, for easier use of a debugger.
- *
- * You will also see calls to any callbacks which wake the connection
- * which is being debugged.
- *
- * Example:
- *	static bool debug_all(struct io_conn *conn)
- *	{
- *		return true();
- *	}
- *	...
- *	io_debug_conn = debug_all;
+ * struct io_plan - one half of I/O to do
+ * @status: the status of this plan.
+ * @io: function to call when fd becomes read/writable, returns 0 to be
+ *      called again, 1 if it's finished, and -1 on error (fd will be closed)
+ * @next: the next function which is called if io returns 1.
+ * @next_arg: the argument to @next
+ * @u1, @u2: scratch space for @io.
  */
-extern bool (*io_debug_conn)(struct io_conn *conn);
+struct io_plan {
+	enum io_plan_status status;
 
-/**
- * io_debug - if we're debugging the current connection, call immediately.
- *
- * This determines if we are debugging the current connection: if so,
- * it immediately applies the plan and calls back into io_loop() to
- * create a linear call chain.
- *
- * Example:
- *	#define io_idle() io_debug(io_idle_())
- *	struct io_plan io_idle_(void);
- */
-struct io_plan io_debug(struct io_plan plan);
+	int (*io)(int fd, struct io_plan *plan);
 
-/**
- * io_debug_io - return from function which actually does I/O.
- *
- * This determines if we are debugging the current connection: if so,
- * it immediately sets the next function and calls into io_loop() to
- * create a linear call chain.
- *
- * Example:
- *
- * static int do_write(int fd, struct io_plan *plan)
- * {
- *	ssize_t ret = write(fd, plan->u.write.buf, plan->u.write.len);
- *	if (ret < 0)
- *		return io_debug_io(-1);
- *
- *	plan->u.write.buf += ret;
- *	plan->u.write.len -= ret;
- *	return io_debug_io(plan->u.write.len == 0);
- * }
- */
-int io_debug_io(int ret);
+	struct io_plan *(*next)(struct io_conn *, void *arg);
+	void *next_arg;
 
-/**
- * io_plan_no_debug - mark the next plan not to be called immediately.
- *
- * Most routines which take a plan are about to apply it to the current
- * connection.  We (ab)use this pattern for debugging: as soon as such a
- * plan is created it is called, to create a linear call chain.
- *
- * Some routines, like io_break(), io_duplex() and io_wake() take an
- * io_plan, but they must not be applied immediately to the current
- * connection, so we call this first.
- *
- * Example:
- * #define io_break(ret, plan) (io_plan_no_debug(), io_break_((ret), (plan)))
- * struct io_plan io_break_(void *ret, struct io_plan plan);
- */
-#define io_plan_no_debug() ((io_plan_nodebug = true))
+	union io_plan_arg u1, u2;
+};
 
-extern bool io_plan_nodebug;
-#else
-static inline struct io_plan io_debug(struct io_plan plan)
-{
-	return plan;
-}
-static inline int io_debug_io(int ret)
-{
-	return ret;
-}
-#define io_plan_no_debug() (void)0
-#endif
+/* Helper to get a conn's io_plan. */
+struct io_plan *io_get_plan(struct io_conn *conn, enum io_direction dir);
 
 #endif /* CCAN_IO_PLAN_H */

ccan/io/poll.c

@@ -9,70 +9,31 @@
 #include <limits.h>
 #include <errno.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)
-{
-	io_alloc.free(conn);
-}
-#endif
+static struct io_conn *closing = NULL, *always = NULL;
 
 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;
 	}
 
@@ -106,19 +67,9 @@ 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;
 	}
@@ -134,106 +85,88 @@ bool add_listener(struct io_listener *l)
 	return true;
 }
 
-void backend_plan_changed(struct io_conn *conn)
+void backend_new_closing(struct io_conn *conn)
 {
-	struct pollfd *pfd;
+	/* Already on always list?  Remove it. */
+	if (conn->list) {
+		struct io_conn **p = &always;
 
-	/* This can happen with debugging and delayed free... */
-	if (conn->fd.backend_info == -1)
-		return;
+		while (*p != conn)
+			p = &(*p)->list;
 
-	pfd = &pollfds[conn->fd.backend_info];
+		*p = conn->list;
+	}
+
+	conn->list = closing;
+	closing = conn;
+}
+
+void backend_new_always(struct io_conn *conn)
+{
+	/* May already be in always list (other plan), or closing. */
+	if (!conn->list) {
+		conn->list = always;
+		always = conn;
+	}
+}
+
+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;
+	}
 }
 
-void backend_wait_changed(const void *wait)
+void backend_wake(const void *wait)
 {
 	unsigned int i;
 
 	for (i = 0; i < num_fds; i++) {
-		struct io_conn *c, *duplex;
+		struct io_conn *c;
 
 		/* Ignore listeners */
 		if (fds[i]->listener)
 			continue;
+
 		c = (void *)fds[i];
-		for (duplex = c->duplex; c; c = duplex, duplex = NULL) {
-			/* Ignore closing. */
-			if (!c->plan.next)
-				continue;
-			/* Not idle? */
-			if (c->plan.io)
-				continue;
-			/* Waiting on something else? */
-			if (c->plan.u1.const_vp != wait)
-				continue;
-			/* Make it do the next thing. */
-			c->plan = io_always_(c->plan.next, c->plan.next_arg);
-			backend_plan_changed(c);
-		}
+		if (c->plan[IO_IN].status == IO_WAITING
+		    && c->plan[IO_IN].u1.const_vp == wait)
+			io_do_wakeup(c, &c->plan[IO_IN]);
+
+		if (c->plan[IO_OUT].status == IO_WAITING
+		    && c->plan[IO_OUT].u1.const_vp == wait)
+			io_do_wakeup(c, &c->plan[IO_OUT]);
 	}
 }
 
 bool add_conn(struct io_conn *c)
 {
-	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;
+	return add_fd(&c->fd, 0);
 }
 
-bool add_duplex(struct io_conn *c)
+static void del_conn(struct io_conn *conn)
 {
-	c->fd.backend_info = c->duplex->fd.backend_info;
-	backend_plan_changed(c);
-	return true;
-}
-
-void backend_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].u1.s;
 		conn->finish(conn, conn->finish_arg);
 	}
-	free_conn(conn);
+	tal_free(conn);
 }
 
 void del_listener(struct io_listener *l)
@@ -241,12 +174,6 @@ 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);
@@ -254,135 +181,73 @@ 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;
 
-	for (i = 0; !io_loop_return && i < num_fds; i++) {
-		struct io_conn *c, *duplex;
+	while (closing) {
+		struct io_conn *conn = closing;
 
-		if (!num_closing)
-			break;
+		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--;
-			}
-		}
+		closing = closing->list;
+		del_conn(conn);
+		ret = true;
 	}
-	return false;
-}
-
-void backend_add_timeout(struct io_conn *conn, struct timerel duration)
-{
-	if (!timeouts.base)
-		timers_init(&timeouts, time_now());
-	timer_add(&timeouts, &conn->timeout->timer,
-		  timeabs_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;
 
-	some_always = false;
+	while (always) {
+		struct io_conn *conn = always;
 
-	for (i = 0; i < num_fds && !io_loop_return; i++) {
-		struct io_conn *c = (void *)fds[i];
+		assert(conn->plan[IO_IN].status == IO_ALWAYS
+		       || conn->plan[IO_OUT].status == IO_ALWAYS);
 
-		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);
+		/* Remove from list, and mark it so it knows that. */
+		always = always->list;
+		conn->list = NULL;
+		io_do_always(conn);
+		ret = true;
 	}
+	return ret;
 }
 
 /* This is the main loop. */
-void *do_io_loop(struct io_conn **ready)
+void *io_loop(void)
 {
 	void *ret;
 
-	io_loop_enter();
-
 	while (!io_loop_return) {
-		int i, r, timeout = INT_MAX;
-		struct timeabs now;
-		bool some_timeouts = false;
-
-		if (timeouts.base) {
-			struct timeabs first;
-			struct list_head expired;
-			struct io_timeout *t;
-
-			now = time_now();
-
-			/* 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;
-			}
+		int i, r;
 
-			/* Now figure out how long to wait for the next one. */
-			if (timer_earliest(&timeouts, &first)) {
-				uint64_t f = time_to_msec(time_between(first, now));
-				if (f < INT_MAX)
-					timeout = f;
-			}
-		}
-
-		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);
+		r = poll(pollfds, num_fds, -1);
 		if (r < 0)
 			break;
 
@@ -400,62 +265,19 @@ 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);
-}

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64001"
-#define main real_main
-int real_main(void);
-#include "run-01-start-finish.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -16,15 +16,17 @@ static void finish_ok(struct io_conn *conn, int *state)
 	ok1(*state == 1);
 	ok1(io_conn_fd(conn) == expected_fd);
 	(*state)++;
-	io_break(state + 1, io_never());
+	io_break(state + 1);
 }
 
-static void init_conn(int fd, int *state)
+static struct io_plan *init_conn(struct io_conn *conn, int *state)
 {
 	ok1(*state == 0);
 	(*state)++;
-	expected_fd = fd;
-	io_set_finish(io_new_conn(fd, io_close()), finish_ok, state);
+	expected_fd = io_conn_fd(conn);
+	io_set_finish(conn, finish_ok, state);
+
+	return io_close(conn);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -70,7 +72,7 @@ int main(void)
 	plan_tests(10);
 	fd = make_listen_fd(PORT, &addrinfo);
 	ok1(fd >= 0);
-	l = io_new_listener(fd, init_conn, &state);
+	l = io_new_listener(NULL, fd, init_conn, &state);
 	ok1(l);
 	fflush(stdout);
 	if (!fork()) {

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64002"
-#define main real_main
-int real_main(void);
-#include "run-02-read.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -19,17 +19,16 @@ static void finish_ok(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 1);
 	d->state++;
-	io_break(d, io_never());
+	io_break(d);
 }
 
-static void init_conn(int fd, struct data *d)
+static struct io_plan *init_conn(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 0);
 	d->state++;
 
-	io_set_finish(io_new_conn(fd,
-				  io_read(d->buf, sizeof(d->buf), io_close_cb, d)),
-		      finish_ok, d);
+	io_set_finish(conn, finish_ok, d);
+	return io_read(conn, d->buf, sizeof(d->buf), io_close_cb, d);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -76,7 +75,7 @@ int main(void)
 	d->state = 0;
 	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);
 	if (!fork()) {

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64003"
-#define main real_main
-int real_main(void);
-#include "run-03-readpartial.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -20,18 +20,18 @@ static void finish_ok(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 1);
 	d->state++;
-	io_break(d, io_never());
+	io_break(d);
 }
 
-static void init_conn(int fd, struct data *d)
+static struct io_plan *init_conn(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 0);
 	d->state++;
-	d->bytes = sizeof(d->buf);
 
-	io_set_finish(io_new_conn(fd,
-				  io_read_partial(d->buf, &d->bytes, io_close_cb, d)),
-		      finish_ok, d);
+	io_set_finish(conn, finish_ok, d);
+
+	return io_read_partial(conn, d->buf, sizeof(d->buf), &d->bytes,
+			       io_close_cb, d);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -96,7 +96,7 @@ int main(void)
 	d->state = 0;
 	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);
 	if (!fork()) {

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64004"
-#define main real_main
-int real_main(void);
-#include "run-04-writepartial.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -20,16 +20,17 @@ static void finish_ok(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 1);
 	d->state++;
-	io_break(d, io_never());
+	io_break(d);
 }
 
-static void init_conn(int fd, struct data *d)
+static struct io_plan *init_conn(struct io_conn *conn, 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_cb, d)),
-				  finish_ok, d);
+	io_set_finish(conn, finish_ok, d);
+
+	return io_write_partial(conn, d->buf, d->bytes, &d->bytes,
+				io_close_cb, d);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -97,7 +98,7 @@ int main(void)
 	memset(d->buf, 'a', d->bytes);
 	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);
 	if (!fork()) {

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64005"
-#define main real_main
-int real_main(void);
-#include "run-05-write.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -20,16 +20,15 @@ static void finish_ok(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 1);
 	d->state++;
-	io_break(d, io_never());
+	io_break(d);
 }
 
-static void init_conn(int fd, struct data *d)
+static struct io_plan *init_conn(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 0);
 	d->state++;
-	io_set_finish(io_new_conn(fd, io_write(d->buf, d->bytes,
-					       io_close_cb, d)),
-		      finish_ok, d);
+	io_set_finish(conn, finish_ok, d);
+	return io_write(conn, d->buf, d->bytes, io_close_cb, d);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -100,7 +99,7 @@ int main(void)
 	memset(d->buf, 'a', d->bytes);
 	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);
 	if (!fork()) {

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64006"
-#define main real_main
-int real_main(void);
-#include "run-06-idle.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -20,11 +20,11 @@ struct data {
 	char buf[4];
 };
 
-static struct io_plan read_done(struct io_conn *conn, struct data *d)
+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();
+	return io_close(conn);
 }
 
 static void finish_waker(struct io_conn *conn, struct data *d)
@@ -38,33 +38,40 @@ static void finish_idle(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 3);
 	d->state++;
-	io_break(d, io_never());
+	io_break(d);
 }
 
-static struct io_plan never(struct io_conn *conn, void *arg)
+static struct io_plan *never(struct io_conn *conn, void *arg)
 {
 	abort();
 }
 
-static struct io_plan read_buf(struct io_conn *conn, struct data *d)
+static struct io_plan *read_buf(struct io_conn *conn, struct data *d)
 {
-	return io_read(d->buf, sizeof(d->buf), read_done, d);
+	return io_read(conn, d->buf, sizeof(d->buf), read_done, d);
 }
 
-static void init_conn(int fd, struct data *d)
+static struct io_plan *init_waker(struct io_conn *conn, void *unused)
+{
+	/* This is /dev/null, so will never succeed. */
+	return io_read(conn, unused, 1, never, NULL);
+}
+
+static struct io_plan *init_idle(struct io_conn *conn, struct data *d)
 {
 	int fd2;
 
 	ok1(d->state == 0);
 	d->state++;
-	idler = io_new_conn(fd, io_wait(d, read_buf, d));
-	io_set_finish(idler, finish_idle, d);
+	idler = conn;
+	io_set_finish(conn, finish_idle, d);
 
 	/* This will wake us up, as read will fail. */
 	fd2 = open("/dev/null", O_RDONLY);
 	ok1(fd2 >= 0);
-	io_set_finish(io_new_conn(fd2, io_read(idler, 1, never, NULL)),
-		      finish_waker, d);
+	io_set_finish(io_new_conn(NULL, fd2, init_waker, d), finish_waker, d);
+
+	return io_wait(conn, d, IO_IN, read_buf, d);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -111,7 +118,7 @@ int main(void)
 	d->state = 0;
 	fd = make_listen_fd(PORT, &addrinfo);
 	ok1(fd >= 0);
-	l = io_new_listener(fd, init_conn, d);
+	l = io_new_listener(NULL, fd, init_idle, d);
 	ok1(l);
 	fflush(stdout);
 	if (!fork()) {

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64007"
-#define main real_main
-int real_main(void);
-#include "run-07-break.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -15,11 +15,11 @@ struct data {
 	char buf[4];
 };
 
-static struct io_plan read_done(struct io_conn *conn, struct data *d)
+static struct io_plan *read_done(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 1);
 	d->state++;
-	return io_close();
+	return io_close(conn);
 }
 
 static void finish_ok(struct io_conn *conn, struct data *d)
@@ -28,15 +28,15 @@ static void finish_ok(struct io_conn *conn, struct data *d)
 	d->state++;
 }
 
-static void init_conn(int fd, struct data *d)
+static struct io_plan *init_conn(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 0);
 	d->state++;
 
-	io_set_finish(io_new_conn(fd,
-				  io_break(d,
-					   io_read(d->buf, sizeof(d->buf), read_done, d))),
-		      finish_ok, d);
+	io_set_finish(conn, finish_ok, d);
+
+	io_break(d);
+	return io_read(conn, d->buf, sizeof(d->buf), read_done, d);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -83,7 +83,7 @@ int main(void)
 	d->state = 0;
 	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);
 	if (!fork()) {

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

@@ -1,7 +0,0 @@
-#define DEBUG
-#define main real_main
-int real_main(void);
-#include "run-08-hangup-on-idle.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -8,39 +8,49 @@
 
 static int fds2[2];
 
-static struct io_plan timeout_wakeup(struct io_conn *conn, char *buf)
+static struct io_plan *read_in(struct io_conn *conn, char *buf)
 {
-	/* This kills the dummy connection. */
-	close(fds2[1]);
-	return io_read(buf, 16, io_close_cb, NULL);
+	return io_read(conn, buf, 16, io_close_cb, NULL);
 }
 
-static struct io_plan never(struct io_conn *conn, void *unused)
+static struct io_plan *setup_waiter(struct io_conn *conn, char *buf)
 {
-	abort();
+	return io_wait(conn, buf, IO_IN, read_in, buf);
+}
+
+static struct io_plan *wake_and_close(struct io_conn *conn, char *buf)
+{
+	io_wake(buf);
+	return io_close(conn);
+}
+
+static struct io_plan *setup_waker(struct io_conn *conn, char *buf)
+{
+	return io_read(conn, buf, 1, wake_and_close, buf);
 }
 
 int main(void)
 {
 	int fds[2];
-	struct io_conn *conn;
 	char buf[16];
 
 	plan_tests(4);
 
 	ok1(pipe(fds) == 0);
 
-	/* Write then close. */
-	io_new_conn(fds[1], io_write("hello there world", 16,
-				     io_close_cb, NULL));
-	conn = io_new_conn(fds[0], io_wait(buf, never, NULL));
-
-	/* To avoid assert(num_waiting) */
+	io_new_conn(NULL, fds[0], setup_waiter, buf);
 	ok1(pipe(fds2) == 0);
-	io_new_conn(fds2[0], io_read(buf, 16, io_close_cb, NULL));
+	io_new_conn(NULL, fds2[0], setup_waker, buf);
+
+	if (fork() == 0) {
+		write(fds[1], "hello there world", 16);
+		close(fds[1]);
 
-	/* After half a second, it will read. */
-	io_timeout(conn, time_from_msec(500), timeout_wakeup, buf);
+		/* Now wake it. */
+		sleep(1);
+		write(fds2[1], "", 1);
+		exit(0);
+	}
 
 	ok1(io_loop() == NULL);
 	ok1(memcmp(buf, "hello there world", 16) == 0);

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

@@ -1,7 +0,0 @@
-#define DEBUG
-#define main real_main
-int real_main(void);
-#include "run-08-read-after-hangup.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -9,15 +9,25 @@
 
 static char inbuf[8];
 
-static struct io_plan wake_it(struct io_conn *conn, struct io_conn *reader)
+static struct io_plan *wake_it(struct io_conn *conn, struct io_conn *reader)
 {
 	io_wake(inbuf);
-	return io_close();
+	return io_close(conn);
 }
 
-static struct io_plan read_buf(struct io_conn *conn, void *unused)
+static struct io_plan *read_buf(struct io_conn *conn, void *unused)
 {
-	return io_read(inbuf, 8, io_close_cb, NULL);
+	return io_read(conn, inbuf, 8, io_close_cb, NULL);
+}
+
+static struct io_plan *init_writer(struct io_conn *conn, struct io_conn *wakeme)
+{
+	return io_write(conn, "EASYTEST", 8, wake_it, wakeme);
+}
+
+static struct io_plan *init_waiter(struct io_conn *conn, void *unused)
+{
+	return io_wait(conn, inbuf, IO_IN, read_buf, NULL);
 }
 
 int main(void)
@@ -28,8 +38,8 @@ int main(void)
 	plan_tests(3);
 
 	ok1(pipe(fds) == 0);
-	conn = io_new_conn(fds[0], io_wait(inbuf, read_buf, NULL));
-	io_new_conn(fds[1], io_write("EASYTEST", 8, wake_it, conn));
+	conn = io_new_conn(NULL, fds[0], init_waiter, NULL);
+	io_new_conn(conn, fds[1], init_writer, conn);
 
 	ok1(io_loop() == NULL);
 	ok1(memcmp(inbuf, "EASYTEST", sizeof(inbuf)) == 0);

ccan/io/test/run-09-connect-DEBUG.c

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64009"
-#define main real_main
-int real_main(void);
-#include "run-09-connect.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

ccan/io/test/run-09-connect.c

@@ -11,31 +11,33 @@
 #endif
 
 static struct io_listener *l;
+static struct data *d2;
 
 struct data {
 	int state;
 	char buf[10];
 };
 
-static struct io_plan closer(struct io_conn *conn, struct data *d)
+static struct io_plan *closer(struct io_conn *conn, struct data *d)
 {
 	d->state++;
-	return io_close();
+	return io_close(conn);
 }
 
-static struct io_plan connected(struct io_conn *conn, struct data *d2)
+static struct io_plan *connected(struct io_conn *conn, struct data *d2)
 {
 	ok1(d2->state == 0);
 	d2->state++;
-	return io_read(d2->buf, sizeof(d2->buf), closer, d2);
+	return io_read(conn, d2->buf, sizeof(d2->buf), closer, d2);
 }
 
-static void init_conn(int fd, struct data *d)
+static struct io_plan *init_conn(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 0);
 	d->state++;
-	io_new_conn(fd, io_write(d->buf, sizeof(d->buf), closer, d));
 	io_close_listener(l);
+
+	return io_write(conn, d->buf, sizeof(d->buf), closer, d);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -70,9 +72,17 @@ static int make_listen_fd(const char *port, struct addrinfo **info)
 	return fd;
 }
 
+static struct io_plan *setup_connect(struct io_conn *conn,
+				     struct addrinfo *addrinfo)
+{
+	d2 = malloc(sizeof(*d2));
+	d2->state = 0;
+	return io_connect(conn, addrinfo, connected, d2);
+}
+
 int main(void)
 {
-	struct data *d = malloc(sizeof(*d)), *d2 = malloc(sizeof(*d2));
+	struct data *d = malloc(sizeof(*d));
 	struct addrinfo *addrinfo;
 	int fd;
 
@@ -82,13 +92,12 @@ int main(void)
 	memset(d->buf, 'a', sizeof(d->buf));
 	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);
 
 	fd = socket(addrinfo->ai_family, addrinfo->ai_socktype,
 		    addrinfo->ai_protocol);
-	d2->state = 0;
-	ok1(io_new_conn(fd, io_connect(fd, addrinfo, connected, d2)));
+	ok1(io_new_conn(NULL, fd, setup_connect, addrinfo));
 
 	ok1(io_loop() == NULL);
 	ok1(d->state == 2);

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

@@ -1,12 +0,0 @@
-#define DEBUG
-#define PORT "64010"
-#define main real_main
-int real_main(void);
-#include "run-10-many.c"
-#undef main
-/* We stack overflow if we debug all of them! */
-static bool debug_one(struct io_conn *conn)
-{
-	return conn == buf[1].reader;
-}
-int main(void) { io_debug_conn = debug_one; return real_main(); }

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

@@ -15,44 +15,49 @@ struct buffer {
 	char buf[32];
 };
 
-static struct io_plan poke_reader(struct io_conn *conn, struct buffer *buf);
-static struct io_plan poke_writer(struct io_conn *conn, struct buffer *buf);
+static struct io_plan *poke_reader(struct io_conn *conn, struct buffer *buf);
+static struct io_plan *poke_writer(struct io_conn *conn, struct buffer *buf);
 
-static struct io_plan read_buf(struct io_conn *conn, struct buffer *buf)
+static struct io_plan *read_buf(struct io_conn *conn, struct buffer *buf)
 {
-	return io_read(&buf->buf, sizeof(buf->buf), poke_writer, buf);
+	return io_read(conn, &buf->buf, sizeof(buf->buf), poke_writer, buf);
 }
 
-static struct io_plan poke_writer(struct io_conn *conn, struct buffer *buf)
+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();
+		return io_close(conn);
 
 	/* You write. */
 	io_wake(&buf->writer);
 
 	/* I'll wait until you wake me. */
-	return io_wait(&buf->reader, read_buf, buf);
+	return io_wait(conn, &buf->reader, IO_IN, read_buf, buf);
 }
 
-static struct io_plan write_buf(struct io_conn *conn, struct buffer *buf)
+static struct io_plan *write_buf(struct io_conn *conn, struct buffer *buf)
 {
-	return io_write(&buf->buf, sizeof(buf->buf), poke_reader, buf);
+	return io_write(conn, &buf->buf, sizeof(buf->buf), poke_reader, buf);
 }
 
-static struct io_plan poke_reader(struct io_conn *conn, struct buffer *buf)
+static struct io_plan *poke_reader(struct io_conn *conn, struct buffer *buf)
 {
 	assert(conn == buf->writer);
 	/* You read. */
 	io_wake(&buf->reader);
 
 	if (++buf->iters == NUM_ITERS)
-		return io_close();
+		return io_close(conn);
 
 	/* I'll wait until you tell me to write. */
-	return io_wait(&buf->writer, write_buf, buf);
+	return io_wait(conn, &buf->writer, IO_OUT, write_buf, buf);
+}
+
+static struct io_plan *setup_reader(struct io_conn *conn, struct buffer *buf)
+{
+	return io_wait(conn, &buf->reader, IO_IN, read_buf, buf);
 }
 
 static struct buffer buf[NUM];
@@ -75,12 +80,11 @@ int main(void)
 		sprintf(buf[i].buf, "%i-%i", i, i);
 
 		/* Wait for writer to tell us to read. */
-		buf[i].reader = io_new_conn(last_read,
-					    io_wait(&buf[i].reader, read_buf,
-						    &buf[i]));
+		buf[i].reader = io_new_conn(NULL, last_read,
+					    setup_reader, &buf[i]);
 		if (!buf[i].reader)
 			break;
-		buf[i].writer = io_new_conn(fds[1], write_buf(NULL, &buf[i]));
+		buf[i].writer = io_new_conn(NULL, fds[1], write_buf, &buf[i]);
 		if (!buf[i].writer)
 			break;
 		last_read = fds[0];
@@ -91,10 +95,9 @@ int main(void)
 	/* Last one completes the cirle. */
 	i = 0;
 	sprintf(buf[i].buf, "%i-%i", i, i);
-	buf[i].reader = io_new_conn(last_read,
-				    io_wait(&buf[i].reader, read_buf, &buf[i]));
+	buf[i].reader = io_new_conn(NULL, last_read, setup_reader, &buf[i]);
 	ok1(buf[i].reader);
-	buf[i].writer = io_new_conn(last_write, write_buf(NULL, &buf[i]));
+	buf[i].writer = io_new_conn(NULL, last_write, write_buf, &buf[i]);
 	ok1(buf[i].writer);
 
 	/* They should eventually exit */

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64012"
-#define main real_main
-int real_main(void);
-#include "run-12-bidir.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -6,6 +6,7 @@
 #include <sys/wait.h>
 #include <stdio.h>
 
+#if 0
 #ifndef PORT
 #define PORT "65012"
 #endif
@@ -22,10 +23,10 @@ static void finish_ok(struct io_conn *conn, struct data *d)
 	d->state++;
 }
 
-static struct io_plan write_done(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();
+	return io_close(conn);
 }
 
 static void init_conn(int fd, struct data *d)
@@ -130,3 +131,9 @@ int main(void)
 	/* This exits depending on whether all tests passed */
 	return exit_status();
 }
+#else
+int main(void)
+{
+	return 0;
+}
+#endif

ccan/io/test/run-13-all-idle-DEBUG.c

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64013"
-#define main real_main
-int real_main(void);
-#include "run-13-all-idle.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

ccan/io/test/run-13-all-idle.c

@@ -7,6 +7,11 @@
 #include <stdio.h>
 #include <signal.h>
 
+static struct io_plan *setup_waiter(struct io_conn *conn, int *status)
+{
+	return io_wait(conn, status, IO_IN, io_close_cb, NULL);
+}
+
 int main(void)
 {
 	int status;
@@ -17,7 +22,7 @@ int main(void)
 		int fds[2];
 
 		ok1(pipe(fds) == 0);
-		io_new_conn(fds[0], io_wait(&status, io_close_cb, NULL));
+		io_new_conn(NULL, fds[0], setup_waiter, &status);
 		io_loop();
 		exit(1);
 	}

ccan/io/test/run-14-duplex-both-read-DEBUG.c

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64014"
-#define main real_main
-int real_main(void);
-#include "run-14-duplex-both-read.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

ccan/io/test/run-14-duplex-both-read.c

@@ -8,6 +8,7 @@
 #include <sys/wait.h>
 #include <stdio.h>
 
+#if 0
 #ifndef PORT
 #define PORT "65014"
 #endif
@@ -138,3 +139,9 @@ int main(void)
 	/* This exits depending on whether all tests passed */
 	return exit_status();
 }
+#else
+int main(void)
+{
+	return 0;
+}
+#endif

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64015"
-#define main real_main
-int real_main(void);
-#include "run-15-timeout.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <unistd.h>
 
+#if 0
 #ifndef PORT
 #define PORT "65015"
 #endif
@@ -38,7 +39,7 @@ static void finish_ok(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 2);
 	d->state++;
-	io_break(d, io_never());
+	io_break(d);
 }
 
 static void init_conn(int fd, struct data *d)
@@ -172,3 +173,9 @@ int main(void)
 	/* This exits depending on whether all tests passed */
 	return exit_status();
 }
+#else
+int main(void)
+{
+	return 0;
+}
+#endif

ccan/io/test/run-16-duplex-test.c

@@ -8,6 +8,7 @@
 #include <sys/wait.h>
 #include <stdio.h>
 
+#if 0
 #ifndef PORT
 #define PORT "65016"
 #endif
@@ -140,3 +141,9 @@ int main(void)
 	/* This exits depending on whether all tests passed */
 	return exit_status();
 }
+#else
+int main(void)
+{
+	return 0;
+}
+#endif

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

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64017"
-#define main real_main
-int real_main(void);
-#include "run-17-homemade-io.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

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

@@ -20,7 +20,7 @@ static void finish_ok(struct io_conn *conn, struct packet *pkt)
 {
 	ok1(pkt->state == 3);
 	pkt->state++;
-	io_break(pkt, io_never());
+	io_break(pkt);
 }
 
 static int do_read_packet(int fd, struct io_plan *plan)
@@ -41,7 +41,7 @@ static int do_read_packet(int fd, struct io_plan *plan)
 		ok1(pkt->state == 2);
 		pkt->state++;
 		if (pkt->len == 0)
-			return io_debug_io(1);
+			return 1;
 		if (!pkt->contents && !(pkt->contents = malloc(pkt->len)))
 			goto fail;
 		else {
@@ -58,39 +58,39 @@ static int do_read_packet(int fd, struct io_plan *plan)
 	plan->u2.s += ret;
 
 	/* Finished? */
-	return io_debug_io(plan->u2.s >= sizeof(pkt->len)
-			   && plan->u2.s == pkt->len + sizeof(pkt->len));
+	return plan->u2.s >= sizeof(pkt->len)
+		&& plan->u2.s == pkt->len + sizeof(pkt->len);
 
 fail:
 	free(pkt->contents);
-	return io_debug_io(-1);
+	return -1;
 }
 
-static struct io_plan io_read_packet(struct packet *pkt,
-				     struct io_plan (*cb)(struct io_conn *, void *),
-				     void *arg)
+static struct io_plan *io_read_packet(struct io_conn *conn,
+				      struct packet *pkt,
+				      struct io_plan *(*cb)(struct io_conn *, void *),
+				      void *arg)
 {
-	struct io_plan plan;
+	struct io_plan *plan = io_get_plan(conn, IO_IN);
 
 	assert(cb);
 	pkt->contents = NULL;
-	plan.u1.vp = pkt;
-	plan.u2.s = 0;
-	plan.io = do_read_packet;
-	plan.next = cb;
-	plan.next_arg = arg;
-	plan.pollflag = POLLIN;
+	plan->u1.vp = pkt;
+	plan->u2.s = 0;
+	plan->io = do_read_packet;
+	plan->next = cb;
+	plan->next_arg = arg;
 
 	return plan;
 }
 
-static void init_conn(int fd, struct packet *pkt)
+static struct io_plan *init_conn(struct io_conn *conn, struct packet *pkt)
 {
 	ok1(pkt->state == 0);
 	pkt->state++;
 
-	io_set_finish(io_new_conn(fd, io_read_packet(pkt, io_close_cb, pkt)),
-		      finish_ok, pkt);
+	io_set_finish(conn, finish_ok, pkt);
+	return io_read_packet(conn, pkt, io_close_cb, pkt);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -137,7 +137,7 @@ int main(void)
 	pkt->state = 0;
 	fd = make_listen_fd(PORT, &addrinfo);
 	ok1(fd >= 0);
-	l = io_new_listener(fd, init_conn, pkt);
+	l = io_new_listener(NULL, fd, init_conn, pkt);
 	ok1(l);
 	fflush(stdout);
 	if (!fork()) {

ccan/io/test/run-18-errno-DEBUG.c

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64018"
-#define main real_main
-int real_main(void);
-#include "run-18-errno.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

ccan/io/test/run-18-errno.c

@@ -22,23 +22,24 @@ static void finish_EBADF(struct io_conn *conn, int *state)
 	ok1(errno == EBADF);
 	ok1(*state == 3);
 	(*state)++;
-	io_break(state + 1, io_close());
+	io_break(state + 1);
 }
 
-static void init_conn(int fd, int *state)
+static struct io_plan *init_conn(struct io_conn *conn, int *state)
 {
 	if (*state == 0) {
 		(*state)++;
 		errno = 100;
-		io_set_finish(io_new_conn(fd, io_close()), finish_100, state);
+		io_set_finish(conn, finish_100, state);
+		return io_close(conn);
 	} else {
 		ok1(*state == 2);
 		(*state)++;
-		close(fd);
+		close(io_conn_fd(conn));
 		errno = 0;
-		io_set_finish(io_new_conn(fd, io_read(state, 1,
-						      io_close_cb, NULL)),
-			      finish_EBADF, state);
+		io_set_finish(conn, finish_EBADF, state);
+
+		return io_read(conn, state, 1, io_close_cb, NULL);
 	}
 }
 
@@ -85,7 +86,7 @@ int main(void)
 	plan_tests(12);
 	fd = make_listen_fd(PORT, &addrinfo);
 	ok1(fd >= 0);
-	l = io_new_listener(fd, init_conn, &state);
+	l = io_new_listener(NULL, fd, init_conn, &state);
 	ok1(l);
 	fflush(stdout);
 	if (!fork()) {

ccan/io/test/run-19-always-DEBUG.c

@@ -1,8 +0,0 @@
-#define DEBUG
-#define PORT "64019"
-#define main real_main
-int real_main(void);
-#include "run-19-always.c"
-#undef main
-static bool always_debug(struct io_conn *conn) { return true; }
-int main(void) { io_debug_conn = always_debug; return real_main(); }

ccan/io/test/run-19-always.c

@@ -20,21 +20,22 @@ static void finish_ok(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 1);
 	d->state++;
-	io_break(d, io_never());
+	io_break(d);
 }
 
-static struct io_plan write_buf(struct io_conn *conn, struct data *d)
+static struct io_plan *write_buf(struct io_conn *conn, struct data *d)
 {
-	return io_write(d->buf, d->bytes, io_close_cb, d);
+	return io_write(conn, d->buf, d->bytes, io_close_cb, d);
 }
 
-static void init_conn(int fd, struct data *d)
+static struct io_plan *init_conn(struct io_conn *conn, struct data *d)
 {
 	ok1(d->state == 0);
 	d->state++;
+	io_set_finish(conn, finish_ok, d);
+
 	/* Empty read should run immediately... */
-	io_set_finish(io_new_conn(fd, io_read(NULL, 0, write_buf, d)),
-		      finish_ok, d);
+	return io_read(conn, NULL, 0, write_buf, d);
 }
 
 static int make_listen_fd(const char *port, struct addrinfo **info)
@@ -105,7 +106,7 @@ int main(void)
 	memset(d->buf, 'a', d->bytes);
 	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);
 	if (!fork()) {

ccan/io/test/run-set_alloc.c

@@ -1,240 +0,0 @@
-#include <ccan/tap/tap.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <signal.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-
-/* Make sure we override these! */
-static void *no_malloc(size_t size)
-{
-	abort();
-}
-static void *no_realloc(void *p, size_t size)
-{
-	abort();
-}
-static void no_free(void *p)
-{
-	abort();
-}
-#define malloc no_malloc
-#define realloc no_realloc
-#define free no_free
-
-#include <ccan/io/poll.c>
-#include <ccan/io/io.c>
-
-#undef malloc
-#undef realloc
-#undef free
-
-static unsigned int alloc_count, realloc_count, free_count;
-static void *ptrs[100];
-
-static void **find_ptr(void *p)
-{
-	unsigned int i;
-
-	for (i = 0; i < 100; i++)
-		if (ptrs[i] == p)
-			return ptrs + i;
-	return NULL;
-}
-
-static void *allocfn(size_t size)
-{
-	alloc_count++;
-	return *find_ptr(NULL) = malloc(size);
-}
-
-static void *reallocfn(void *ptr, size_t size)
-{
-	realloc_count++;
-	if (!ptr)
-		alloc_count++;
-
-	return *find_ptr(ptr) = realloc(ptr, size);
-}
-
-static void freefn(void *ptr)
-{
-	free_count++;
-	free(ptr);
-	*find_ptr(ptr) = NULL;
-}
-
-#ifndef PORT
-#define PORT "65115"
-#endif
-
-struct data {
-	int state;
-	int timeout_usec;
-	bool timed_out;
-	char buf[4];
-};
-
-
-static struct io_plan no_timeout(struct io_conn *conn, struct data *d)
-{
-	ok1(d->state == 1);
-	d->state++;
-	return io_close();
-}
-
-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();
-}
-
-static void finish_ok(struct io_conn *conn, struct data *d)
-{
-	ok1(d->state == 2);
-	d->state++;
-	io_break(d, io_never());
-}
-
-static void init_conn(int fd, 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));
-	io_set_finish(conn, finish_ok, d);
-	io_timeout(conn, time_from_usec(d->timeout_usec), timeout, d);
-}
-
-static int make_listen_fd(const char *port, struct addrinfo **info)
-{
-	int fd, on = 1;
-	struct addrinfo *addrinfo, hints;
-
-	memset(&hints, 0, sizeof(hints));
-	hints.ai_family = AF_UNSPEC;
-	hints.ai_socktype = SOCK_STREAM;
-	hints.ai_flags = AI_PASSIVE;
-	hints.ai_protocol = 0;
-
-	if (getaddrinfo(NULL, port, &hints, &addrinfo) != 0)
-		return -1;
-
-	fd = socket(addrinfo->ai_family, addrinfo->ai_socktype,
-		    addrinfo->ai_protocol);
-	if (fd < 0)
-		return -1;
-
-	setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
-	if (bind(fd, addrinfo->ai_addr, addrinfo->ai_addrlen) != 0) {
-		close(fd);
-		return -1;
-	}
-	if (listen(fd, 1) != 0) {
-		close(fd);
-		return -1;
-	}
-	*info = addrinfo;
-	return fd;
-}
-
-int main(void)
-{
-	struct data *d = allocfn(sizeof(*d));
-	struct addrinfo *addrinfo;
-	struct io_listener *l;
-	int fd, status;
-
-	io_set_alloc(allocfn, reallocfn, freefn);
-
-	/* This is how many tests you plan to run */
-	plan_tests(25);
-	d->state = 0;
-	d->timed_out = false;
-	d->timeout_usec = 100000;
-	fd = make_listen_fd(PORT, &addrinfo);
-	ok1(fd >= 0);
-	l = io_new_listener(fd, init_conn, d);
-	ok1(l);
-	fflush(stdout);
-
-	if (!fork()) {
-		int i;
-
-		io_close_listener(l);
-		fd = socket(addrinfo->ai_family, addrinfo->ai_socktype,
-			    addrinfo->ai_protocol);
-		if (fd < 0)
-			exit(1);
-		if (connect(fd, addrinfo->ai_addr, addrinfo->ai_addrlen) != 0)
-			exit(2);
-		signal(SIGPIPE, SIG_IGN);
-		usleep(500000);
-		for (i = 0; i < strlen("hellothere"); i++) {
-			if (write(fd, "hellothere" + i, 1) != 1)
-				break;
-		}
-		close(fd);
-		freeaddrinfo(addrinfo);
-		free(d);
-		exit(i);
-	}
-	ok1(io_loop() == d);
-	ok1(d->state == 3);
-	ok1(d->timed_out == true);
-	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);
-
-	if (!fork()) {
-		int i;
-
-		io_close_listener(l);
-		fd = socket(addrinfo->ai_family, addrinfo->ai_socktype,
-			    addrinfo->ai_protocol);
-		if (fd < 0)
-			exit(1);
-		if (connect(fd, addrinfo->ai_addr, addrinfo->ai_addrlen) != 0)
-			exit(2);
-		signal(SIGPIPE, SIG_IGN);
-		usleep(100000);
-		for (i = 0; i < strlen("hellothere"); i++) {
-			if (write(fd, "hellothere" + i, 1) != 1)
-				break;
-		}
-		close(fd);
-		freeaddrinfo(addrinfo);
-		free(d);
-		exit(i);
-	}
-	ok1(io_loop() == d);
-	ok1(d->state == 3);
-	ok1(d->timed_out == false);
-	ok1(wait(&status));
-	ok1(WIFEXITED(status));
-	ok1(WEXITSTATUS(status) >= sizeof(d->buf));
-
-	io_close_listener(l);
-	freeaddrinfo(addrinfo);
-
-	/* We should have tested each one at least once! */
-	ok1(realloc_count);
-	ok1(alloc_count);
-	ok1(free_count);
-
-	ok1(free_count < alloc_count);
-	freefn(d);
-	ok1(free_count == alloc_count);
-
-	return exit_status();
-}