X-Git-Url: http://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Fio%2Fio.c;h=bdcbf9e26b8f9f580fea08c2c0913d31efe9dcc7;hb=9f06b8f85927202c05751e43f285cbef8054052b;hp=7eea9c35442cbbcb4386b430929195d1454b49a0;hpb=e2e70f5566cb8978b74de517c24a0f236d3d01ee;p=ccan

diff --git a/ccan/io/io.c b/ccan/io/io.c
index 7eea9c35..bdcbf9e2 100644
--- a/ccan/io/io.c
+++ b/ccan/io/io.c
@@ -131,7 +131,7 @@ struct io_plan_arg *io_plan_arg(struct io_conn *conn, enum io_direction dir)
 {
 	assert(conn->plan[dir].status == IO_UNSET);
 
-	conn->plan[dir].status = IO_POLLING;
+	conn->plan[dir].status = IO_POLLING_NOTSTARTED;
 	return &conn->plan[dir].arg;
 }
 
@@ -202,8 +202,12 @@ struct io_plan *io_write_(struct io_conn *conn, const void *data, size_t len,
 static int do_read(int fd, struct io_plan_arg *arg)
 {
 	ssize_t ret = read(fd, arg->u1.cp, arg->u2.s);
-	if (ret <= 0)
+	if (ret <= 0) {
+		/* Errno isn't set if we hit EOF, so set it to distinct value */
+		if (ret == 0)
+			errno = 0;
 		return -1;
+	}
 
 	arg->u1.cp += ret;
 	arg->u2.s -= ret;
@@ -230,8 +234,12 @@ struct io_plan *io_read_(struct io_conn *conn,
 static int do_read_partial(int fd, struct io_plan_arg *arg)
 {
 	ssize_t ret = read(fd, arg->u1.cp, *(size_t *)arg->u2.vp);
-	if (ret <= 0)
+	if (ret <= 0) {
+		/* Errno isn't set if we hit EOF, so set it to distinct value */
+		if (ret == 0)
+			errno = 0;
 		return -1;
+	}
 
 	*(size_t *)arg->u2.vp = ret;
 	return 1;
@@ -368,7 +376,8 @@ static bool do_plan(struct io_conn *conn, struct io_plan *plan,
 		    bool idle_on_epipe)
 {
 	/* We shouldn't have polled for this event if this wasn't true! */
-	assert(plan->status == IO_POLLING);
+	assert(plan->status == IO_POLLING_NOTSTARTED
+	       || plan->status == IO_POLLING_STARTED);
 
 	switch (plan->io(conn->fd.fd, &plan->arg)) {
 	case -1:
@@ -380,6 +389,7 @@ static bool do_plan(struct io_conn *conn, struct io_plan *plan,
 		io_close(conn);
 		return false;
 	case 0:
+		plan->status = IO_POLLING_STARTED;
 		return true;
 	case 1:
 		return next_plan(conn, plan);
@@ -399,8 +409,8 @@ void io_ready(struct io_conn *conn, int pollflags)
 		/* If we're writing to a closed pipe, we need to wait for
 		 * read to fail if we're duplex: we want to drain it! */
 		do_plan(conn, &conn->plan[IO_OUT],
-			(conn->plan[IO_IN].status == IO_POLLING
-			 || conn->plan[IO_IN].status == IO_ALWAYS));
+			conn->plan[IO_IN].status == IO_POLLING_NOTSTARTED
+			|| conn->plan[IO_IN].status == IO_POLLING_STARTED);
 }
 
 void io_do_always(struct io_conn *conn)
@@ -510,13 +520,24 @@ struct io_plan *io_set_plan(struct io_conn *conn, enum io_direction dir,
 	return plan;
 }
 
+bool io_plan_in_started(const struct io_conn *conn)
+{
+	return conn->plan[IO_IN].status == IO_POLLING_STARTED;
+}
+
+bool io_plan_out_started(const struct io_conn *conn)
+{
+	return conn->plan[IO_OUT].status == IO_POLLING_STARTED;
+}
+
 bool io_flush_sync(struct io_conn *conn)
 {
 	struct io_plan *plan = &conn->plan[IO_OUT];
 	bool ok;
 
 	/* Not writing?  Nothing to do. */
-	if (plan->status != IO_POLLING)
+	if (plan->status != IO_POLLING_STARTED
+	    && plan->status != IO_POLLING_NOTSTARTED)
 		return true;
 
 	/* Synchronous please. */
@@ -529,6 +550,7 @@ again:
 		break;
 	/* Incomplete, try again. */
 	case 0:
+		plan->status = IO_POLLING_STARTED;
 		goto again;
 	case 1:
 		ok = true;