ccan/io: io_halfclose.

[ccan] / ccan / io / io.c

diff --git a/ccan/io/io.c b/ccan/io/io.c
index 6d1c0522d131c8e15809b8deb2e84ba752710302..7f5113d344c4b5ba199121593c2d5903e236dfd9 100644 (file)
--- a/ccan/io/io.c
+++ b/ccan/io/io.c
@@ -437,6 +437,24 @@ struct io_plan *io_duplex_(struct io_plan *in_plan, struct io_plan *out_plan)
        return out_plan + 1;
 }
 
+struct io_plan *io_halfclose(struct io_conn *conn)
+{
+       /* Already closing?  Don't close twice. */
+       if (conn->plan[IO_IN].status == IO_CLOSING)
+               return &conn->plan[IO_IN];
+
+       /* Both unset?  OK. */
+       if (conn->plan[IO_IN].status == IO_UNSET
+           && conn->plan[IO_OUT].status == IO_UNSET)
+               return io_close(conn);
+
+       /* We leave this unset then. */
+       if (conn->plan[IO_IN].status == IO_UNSET)
+               return &conn->plan[IO_IN];
+       else
+               return &conn->plan[IO_OUT];
+}
+
 struct io_plan *io_set_plan(struct io_conn *conn, enum io_direction dir,
                            int (*io)(int fd, struct io_plan_arg *arg),
                            struct io_plan *(*next)(struct io_conn *, void *),