#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
+};
/**
- * 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;
+ /* Only NULL if idle. */
+ enum io_result (*io)(struct io_conn *conn);
+ /* Only NULL if closing. */
+ 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.
* @fd: the file descriptor.
- * @start: the first function to call.
+ * @plan: the first I/O function.
* @finish: the function to call when it's closed or fails.
- * @arg: the argument to both @start and @finish.
+ * @arg: the argument to @finish.
*
- * This creates a connection which owns @fd. @start will be called on the
- * next return to io_loop(), and @finish will be called when an I/O operation
+ * 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.
*
- * The @start function must call one of the io queueing functions
- * (eg. io_read, io_write) and return the next function to call once
- * that is done using io_next(). The alternative is to call io_close().
- *
* Returns NULL on error (and sets errno).
*/
-#define io_new_conn(fd, start, finish, arg) \
- io_new_conn_((fd), \
- typesafe_cb_preargs(struct io_op *, void *, \
- (start), (arg), struct io_conn *), \
+#define io_new_conn(fd, plan, finish, arg) \
+ 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_op *(*start)(struct io_conn *, void *),
+ struct io_plan plan,
void (*finish)(struct io_conn *, void *),
void *arg);
/**
* io_new_listener - create a new accepting listener.
* @fd: the file descriptor.
- * @start: the first function to call on new connections.
- * @finish: the function to call when the connection is closed or fails.
- * @arg: the argument to both @start and @finish.
+ * @init: the function to call for a new connection
+ * @arg: the argument to @init.
*
- * When @fd becomes readable, we accept() and turn that fd into a new
- * connection.
+ * When @fd becomes readable, we accept() and pass that fd to init().
*
* Returns NULL on error (and sets errno).
*/
-#define io_new_listener(fd, start, finish, arg) \
+#define io_new_listener(fd, init, arg) \
io_new_listener_((fd), \
- typesafe_cb_preargs(struct io_op *, void *, \
- (start), (arg), \
- struct io_conn *), \
- typesafe_cb_preargs(void, void *, (finish), \
- (arg), struct io_conn *), \
+ typesafe_cb_preargs(void, void *, \
+ (init), (arg), \
+ int fd), \
(arg))
struct io_listener *io_new_listener_(int fd,
- struct io_op *(*start)(struct io_conn *,
- void *arg),
- void (*finish)(struct io_conn *,
- void *arg),
+ void (*init)(int fd, void *arg),
void *arg);
/**
* io_write - queue data to be written.
* @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(data, len, cb, arg) \
+ 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);
/**
* io_read - queue buffer to be read.
* @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(data, len, cb, arg) \
+ 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);
+
/**
* io_read_partial - queue buffer to be read (partial OK).
* @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(data, len, cb, arg) \
+ 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);
/**
* io_write_partial - queue data to be written (partial OK).
* @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(data, len, cb, arg) \
+ 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);
+
/**
* io_idle - explicitly note that this connection will do nothing.
- * @conn: the current connection.
*
* This indicates the connection is idle: some other function will
* 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(void);
/**
* io_timeout - set timeout function if the callback doesn't fire.
* @conn: the current connection.
* @ts: how long until the timeout should be called.
- * @next: function to call.
- * @arg: argument to @next.
+ * @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
* Returns false on allocation failure. A connection can only have one
* timeout.
*/
-#define io_timeout(conn, ts, next, arg) \
+#define io_timeout(conn, ts, fn, arg) \
io_timeout_((conn), (ts), \
- typesafe_cb_preargs(struct io_op *, void *, \
- (next), (arg), \
+ 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_op *(*next)(struct io_conn *, void *), void *arg);
+ 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.
+ * @plan: the first I/O function to call.
* @finish: the function to call when it's closed or fails.
- * @arg: the argument to both @start and @finish.
+ * @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
*
* 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_op *, void *, \
- (start), (arg), struct io_conn *), \
+#define io_duplex(conn, plan, finish, arg) \
+ io_duplex_((conn), (plan), \
typesafe_cb_preargs(void, void *, (finish), (arg), \
struct io_conn *), \
(arg))
struct io_conn *io_duplex_(struct io_conn *conn,
- struct io_op *(*start)(struct io_conn *, void *),
+ struct io_plan plan,
void (*finish)(struct io_conn *, void *),
void *arg);
/**
- * io_wake - wake up and idle connection.
+ * io_wake - wake up an idle connection.
* @conn: an idle connection.
- * @next: the next function to call once queued IO is complete.
- * @arg: the argument to @next.
+ * @plan: the next I/O function for @conn.
*
- * This makes @conn run its @next function the next time around the
- * io_loop().
+ * This makes @conn do I/O the next time around the io_loop().
*/
-#define io_wake(conn, next, arg) \
- io_wake_((conn), \
- typesafe_cb_preargs(struct io_op *, void *, \
- (next), (arg), struct io_conn *), \
- (arg))
-void io_wake_(struct io_conn *conn,
- struct io_op *(*next)(struct io_conn *, void *), void *arg);
+void io_wake(struct io_conn *conn, struct io_plan plan);
/**
* 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).
+ * @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 @arg.
+ * finish callbacks called, then io_loop() with return with @ret.
*
- * If io_loop() is called again, then @next will be called.
+ * If io_loop() is called again, then @plan will be carried out.
*/
-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.
- *
- * 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.
- */
-#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),
- void *arg);
+struct io_plan io_break(void *ret, struct io_plan plan);
/* 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