-/* Licensed under BSD-MIT - see LICENSE file for details */
+/* Licensed under LGPLv2.1+ - see LICENSE file for details */
#ifndef CCAN_IO_H
#define CCAN_IO_H
#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <ccan/time/time.h>
#include <stdbool.h>
#include <unistd.h>
-/**
- * struct io_op - pointer to return from io functions.
- *
- * This undefined structure is just to help the compiler check that you
- * really do return the result of an io-queueing method.
- */
-struct io_op;
+struct io_conn;
+
+struct io_state_read {
+ char *buf;
+ size_t len;
+};
+
+struct io_state_write {
+ const char *buf;
+ size_t len;
+};
+
+struct io_state_readpart {
+ char *buf;
+ size_t *lenp;
+};
+
+struct io_state_writepart {
+ const char *buf;
+ size_t *lenp;
+};
+
+enum io_result {
+ RESULT_AGAIN,
+ RESULT_FINISHED,
+ RESULT_CLOSE
+};
+
+enum io_state {
+ IO_IO,
+ IO_NEXT, /* eg starting, woken from idle, return from io_break. */
+ IO_IDLE,
+ IO_FINISHED
+};
/**
- * struct io_next - pointer to what we're going to do next.
+ * struct io_plan - returned from a setup function.
*
- * Bundles up callbacks, generated by io_next().
+ * A plan of what IO to do, when.
*/
-struct io_next;
+struct io_plan {
+ int pollflag;
+ enum io_state state;
+ enum io_result (*io)(struct io_conn *conn);
+ struct io_plan (*next)(struct io_conn *, void *arg);
+ void *next_arg;
+
+ union {
+ struct io_state_read read;
+ struct io_state_write write;
+ struct io_state_readpart readpart;
+ struct io_state_writepart writepart;
+ } u;
+};
/**
* io_new_conn - create a new connection.
*/
#define io_new_conn(fd, start, finish, arg) \
io_new_conn_((fd), \
- typesafe_cb_preargs(struct io_op *, void *, \
+ typesafe_cb_preargs(struct io_plan, void *, \
(start), (arg), struct io_conn *), \
typesafe_cb_preargs(void, void *, (finish), (arg), \
struct io_conn *), \
(arg))
struct io_conn *io_new_conn_(int fd,
- struct io_op *(*start)(struct io_conn *, void *),
+ struct io_plan (*start)(struct io_conn *, void *),
void (*finish)(struct io_conn *, void *),
void *arg);
*/
#define io_new_listener(fd, start, finish, arg) \
io_new_listener_((fd), \
- typesafe_cb_preargs(struct io_op *, void *, \
+ typesafe_cb_preargs(struct io_plan, void *, \
(start), (arg), \
struct io_conn *), \
typesafe_cb_preargs(void, void *, (finish), \
(arg), struct io_conn *), \
(arg))
struct io_listener *io_new_listener_(int fd,
- struct io_op *(*start)(struct io_conn *,
- void *arg),
+ struct io_plan (*start)(struct io_conn *,
+ void *arg),
void (*finish)(struct io_conn *,
void *arg),
void *arg);
/**
* io_write - queue data to be written.
+ * @conn: the current connection.
* @data: the data buffer.
* @len: the length to write.
- * @next: what to call next.
+ * @cb: function to call once it's done.
+ * @arg: @cb argument
*
- * This will queue the data buffer for writing. Once it's all written, the
- * function registered with io_next() will be called: on an error, the finish
+ * This will queue the data buffer for writing. Once it's all
+ * written, the @cb function will be called: on an error, the finish
* function is called instead.
*
* Note that the I/O may actually be done immediately.
*/
-struct io_op *io_write(const void *data, size_t len, struct io_next *next);
+#define io_write(conn, data, len, cb, arg) \
+ io_write_((conn), (data), (len), \
+ typesafe_cb_preargs(struct io_plan, void *, \
+ (cb), (arg), struct io_conn *), \
+ (arg))
+struct io_plan io_write_(struct io_conn *conn, const void *data, size_t len,
+ struct io_plan (*cb)(struct io_conn *, void *),
+ void *arg);
/**
* io_read - queue buffer to be read.
+ * @conn: the current connection.
* @data: the data buffer.
* @len: the length to read.
- * @next: what to call next.
+ * @cb: function to call once it's done.
+ * @arg: @cb argument
*
- * This will queue the data buffer for reading. Once it's all read, the
- * function registered with io_next() will be called: on an error, the finish
- * function is called instead.
+ * This will queue the data buffer for reading. Once it's all read,
+ * the @cb function will be called: on an error, the finish function
+ * is called instead.
*
* Note that the I/O may actually be done immediately.
*/
-struct io_op *io_read(void *data, size_t len, struct io_next *next);
+#define io_read(conn, data, len, cb, arg) \
+ io_read_((conn), (data), (len), \
+ typesafe_cb_preargs(struct io_plan, void *, \
+ (cb), (arg), struct io_conn *), \
+ (arg))
+struct io_plan io_read_(struct io_conn *conn, void *data, size_t len,
+ struct io_plan (*cb)(struct io_conn *, void *),
+ void *arg);
+
/**
* io_read_partial - queue buffer to be read (partial OK).
+ * @conn: the current connection.
* @data: the data buffer.
* @len: the maximum length to read, set to the length actually read.
- * @next: what to call next.
+ * @cb: function to call once it's done.
+ * @arg: @cb argument
*
* This will queue the data buffer for reading. Once any data is
- * read, @len is updated and the function registered with io_next()
- * will be called: on an error, the finish function is called instead.
+ * read, @len is updated and the @cb function will be called: on an
+ * error, the finish function is called instead.
*
* Note that the I/O may actually be done immediately.
*/
-struct io_op *io_read_partial(void *data, size_t *len, struct io_next *next);
+#define io_read_partial(conn, data, len, cb, arg) \
+ io_read_partial_((conn), (data), (len), \
+ typesafe_cb_preargs(struct io_plan, void *, \
+ (cb), (arg), struct io_conn *), \
+ (arg))
+struct io_plan io_read_partial_(struct io_conn *conn, void *data, size_t *len,
+ struct io_plan (*cb)(struct io_conn *, void *),
+ void *arg);
/**
* io_write_partial - queue data to be written (partial OK).
+ * @conn: the current connection.
* @data: the data buffer.
* @len: the maximum length to write, set to the length actually written.
- * @next: what to call next.
+ * @cb: function to call once it's done.
+ * @arg: @cb argument
*
* This will queue the data buffer for writing. Once any data is
- * written, @len is updated and the function registered with io_next()
- * will be called: on an error, the finish function is called instead.
+ * written, @len is updated and the @cb function will be called: on an
+ * error, the finish function is called instead.
*
* Note that the I/O may actually be done immediately.
*/
-struct io_op *io_write_partial(const void *data, size_t *len,
- struct io_next *next);
+#define io_write_partial(conn, data, len, cb, arg) \
+ io_write_partial_((conn), (data), (len), \
+ typesafe_cb_preargs(struct io_plan, void *, \
+ (cb), (arg), struct io_conn *), \
+ (arg))
+struct io_plan io_write_partial_(struct io_conn *conn,
+ const void *data, size_t *len,
+ struct io_plan (*cb)(struct io_conn *, void*),
+ void *arg);
+
/**
* io_idle - explicitly note that this connection will do nothing.
* later call io_read/io_write etc. (or io_close) on it, in which case
* it will do that.
*/
-struct io_op *io_idle(struct io_conn *conn);
+struct io_plan io_idle(struct io_conn *conn);
+
+/**
+ * io_timeout - set timeout function if the callback doesn't fire.
+ * @conn: the current connection.
+ * @ts: how long until the timeout should be called.
+ * @cb 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.
+ */
+#define io_timeout(conn, ts, fn, arg) \
+ io_timeout_((conn), (ts), \
+ typesafe_cb_preargs(struct io_plan, void *, \
+ (fn), (arg), \
+ struct io_conn *), \
+ (arg))
+bool io_timeout_(struct io_conn *conn, struct timespec ts,
+ struct io_plan (*fn)(struct io_conn *, void *), void *arg);
+
+/**
+ * io_duplex - split an fd into two connections.
+ * @conn: a connection.
+ * @start: the first function to call.
+ * @finish: the function to call when it's closed or fails.
+ * @arg: the argument to both @start and @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
+ * to have two connections for the same fd, and use one for read
+ * operations and one for write.
+ *
+ * You must io_close() both of them to close the fd.
+ */
+#define io_duplex(conn, start, finish, arg) \
+ io_duplex_((conn), \
+ typesafe_cb_preargs(struct io_plan, void *, \
+ (start), (arg), struct io_conn *), \
+ typesafe_cb_preargs(void, void *, (finish), (arg), \
+ struct io_conn *), \
+ (arg))
+
+struct io_conn *io_duplex_(struct io_conn *conn,
+ struct io_plan (*start)(struct io_conn *, void *),
+ void (*finish)(struct io_conn *, void *),
+ void *arg);
/**
* io_wake - wake up and idle connection.
* @conn: an idle connection.
- * @next: the next function to call once queued IO is complete.
+ * @fn: the next function to call once queued IO is complete.
* @arg: the argument to @next.
*
* This makes @conn run its @next function the next time around the
* io_loop().
*/
-#define io_wake(conn, next, arg) \
+#define io_wake(conn, fn, arg) \
io_wake_((conn), \
- typesafe_cb_preargs(struct io_op *, void *, \
- (next), (arg), struct io_conn *), \
+ typesafe_cb_preargs(struct io_plan, void *, \
+ (fn), (arg), struct io_conn *), \
(arg))
void io_wake_(struct io_conn *conn,
- struct io_op *(*next)(struct io_conn *, void *), void *arg);
+ struct io_plan (*fn)(struct io_conn *, void *), void *arg);
/**
* io_break - return from io_loop()
- * @arg: non-NULL value to return from io_loop().
- * @next: what to call next (can be NULL if we expect no return).
+ * @conn: the current connection.
+ * @ret: non-NULL value to return from io_loop().
+ * @cb: function to call once on return
+ * @arg: @cb argument
*
* 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 @arg.
- *
- * If io_loop() is called again, then @next will be called.
- */
-struct io_op *io_break(void *arg, struct io_next *next);
-
-/**
- * io_next - indicate what callback to call next.
- * @conn: this connection.
- * @next: the next function to call once queued IO is complete.
- * @arg: the argument to @next.
+ * finish callbacks called, then io_loop() with return with @ret.
*
- * Every @next (or @start) function should "return io_next(...);" once
- * they have indicated what io to perform (eg. io_write, io_idle).
- * The exception is io_close(), which can be used instead of io_next().
- *
- * Note that as an optimization, the next function may be called
- * immediately, which is why this should be the last statement in your
- * function.
+ * If io_loop() is called again, then @cb will be called.
*/
-#define io_next(conn, next, arg) \
- io_next_((conn), \
- typesafe_cb_preargs(struct io_op *, void *, \
- (next), (arg), struct io_conn *), \
- (arg))
-struct io_next *io_next_(struct io_conn *conn,
- struct io_op *(*next)(struct io_conn *, void *arg),
+#define io_break(conn, ret, fn, arg) \
+ io_break_((conn), (ret), \
+ typesafe_cb_preargs(struct io_plan, void *, \
+ (fn), (arg), struct io_conn *), \
+ (arg))
+struct io_plan io_break_(struct io_conn *conn, void *ret,
+ struct io_plan (*fn)(struct io_conn *, void *),
void *arg);
/* FIXME: io_recvfrom/io_sendto */
* It's common to 'return io_close(...)' from a @next function, but
* io_close can also be used as an argument to io_next().
*/
-struct io_op *io_close(struct io_conn *, void *unused);
+struct io_plan io_close(struct io_conn *, void *unused);
/**
* io_loop - process fds until all closed on io_break.
projects / ccan / blobdiff