ccan/io: handle errors on poll()

[ccan] / ccan / io / io.h

diff --git a/ccan/io/io.h b/ccan/io/io.h
index 72f805244c91ad89c4404703f4b276608339142f..8199bda9802050f747440f66ec1da97f987fcb47 100644 (file)
--- a/ccan/io/io.h
+++ b/ccan/io/io.h
@@ -16,7 +16,7 @@ struct io_conn;
 struct io_plan {
        int pollflag;
        /* Only NULL if idle. */
-       bool (*io)(int fd, struct io_plan *plan);
+       int (*io)(int fd, struct io_plan *plan);
        /* Only NULL if closing. */
        struct io_plan (*next)(struct io_conn *, void *arg);
        void *next_arg;
@@ -67,25 +67,34 @@ static inline void io_plan_debug(struct io_plan *plan) { }
  * io_new_conn - create a new connection.
  * @fd: the file descriptor.
  * @plan: the first I/O function.
- * @finish: the function to call when it's closed or fails.
- * @arg: the argument to @finish.
  *
  * This creates a connection which owns @fd.  @plan will be called on the
- * next io_loop(), and @finish will be called when an I/O operation
- * fails, or you call io_close() on the connection.
+ * next io_loop().
  *
  * Returns NULL on error (and sets errno).
  */
-#define io_new_conn(fd, plan, finish, arg)                             \
-       (io_plan_other(), io_new_conn_((fd), (plan),                    \
-                                      typesafe_cb_preargs(void, void *, \
-                                                          (finish), (arg), \
-                                                          struct io_conn *), \
-                                      (arg)))
-struct io_conn *io_new_conn_(int fd,
-                            struct io_plan plan,
-                            void (*finish)(struct io_conn *, void *),
-                            void *arg);
+#define io_new_conn(fd, plan)                          \
+       (io_plan_other(), io_new_conn_((fd), (plan)))
+struct io_conn *io_new_conn_(int fd, struct io_plan plan);
+
+/**
+ * io_set_finish - set finish function on a connection.
+ * @conn: the connection.
+ * @finish: the function to call when it's closed or fails.
+ * @arg: the argument to @finish.
+ *
+ * @finish will be called when an I/O operation fails, or you call
+ * io_close() on the connection.
+ */
+#define io_set_finish(conn, finish, arg)                               \
+       io_set_finish_((conn),                                          \
+                      typesafe_cb_preargs(void, void *,                \
+                                          (finish), (arg),             \
+                                          struct io_conn *),           \
+                      (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.
@@ -241,8 +250,6 @@ bool io_timeout_(struct io_conn *conn, struct timespec ts,
  * io_duplex - split an fd into two connections.
  * @conn: a connection.
  * @plan: the first I/O function to call.
- * @finish: the function to call when it's closed or fails.
- * @arg: the argument to @finish.
  *
  * Sometimes you want to be able to simultaneously read and write on a
  * single fd, but io forces a linear call sequence.  The solition is
@@ -251,17 +258,10 @@ bool io_timeout_(struct io_conn *conn, struct timespec ts,
  *
  * You must io_close() both of them to close the fd.
  */
-#define io_duplex(conn, plan, finish, arg)                             \
-       (io_plan_other(), io_duplex_((conn), (plan),                    \
-                                    typesafe_cb_preargs(void, void *,  \
-                                                        (finish), (arg), \
-                                                        struct io_conn *), \
-                                    (arg)))
+#define io_duplex(conn, plan)                          \
+       (io_plan_other(), io_duplex_((conn), (plan)))
 
-struct io_conn *io_duplex_(struct io_conn *conn,
-                          struct io_plan plan,
-                          void (*finish)(struct io_conn *, void *),
-                          void *arg);
+struct io_conn *io_duplex_(struct io_conn *conn, struct io_plan plan);
 
 /**
  * io_wake - wake up an idle connection.
@@ -290,17 +290,20 @@ struct io_plan io_break_(void *ret, struct io_plan plan);
 /* FIXME: io_recvfrom/io_sendto */
 
 /**
- * io_close - terminate a connection.
- * @conn: any connection.
+ * io_close - plan to close a connection.
  *
- * The schedules a connection to be closed.  It can be done on any
- * connection, whether it has I/O queued or not (though that I/O may
- * be performed first).
+ * On return to io_loop, the connection will be closed.
+ */
+struct io_plan io_close(void);
+
+/**
+ * io_close_cb - helper callback to close a connection.
+ * @conn: the connection.
  *
- * It's common to 'return io_close(...)' from a @next function, but
- * io_close can also be used as an argument to io_next().
+ * This schedules a connection to be closed; designed to be used as
+ * a callback function.
  */
-struct io_plan io_close(struct io_conn *, void *unused);
+struct io_plan io_close_cb(struct io_conn *, void *unused);
 
 /**
  * io_loop - process fds until all closed on io_break.