X-Git-Url: https://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Fio%2Fio.h;h=828fb666f50fcde0acdfbe107467c000ecedd2ba;hb=d4af94ec86618e89b449a27590a7b4f8e4365943;hp=e48f15b52efe25643b64b533871a64778cdcba60;hpb=733b09fa8b6083949ff62795e54851aa282d510c;p=ccan diff --git a/ccan/io/io.h b/ccan/io/io.h index e48f15b5..828fb666 100644 --- a/ccan/io/io.h +++ b/ccan/io/io.h @@ -5,116 +5,60 @@ #include #include #include - -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 -}; +#include "io_plan.h" /** - * struct io_plan - returned from a setup function. + * io_new_conn - create a new connection. + * @fd: the file descriptor. + * @plan: the first I/O to perform. + * + * This creates a connection which owns @fd. @plan will be called on the + * next io_loop(). * - * A plan of what IO to do, when. + * Returns NULL on error (and sets errno). */ -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; -}; +#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_new_conn - create a new connection. - * @fd: the file descriptor. - * @start: the first function to call. + * 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 both @start and @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 - * 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(). + * @arg: the argument to @finish. * - * Returns NULL on error (and sets errno). + * @finish will be called when an I/O operation fails, or you call + * io_close() on the connection. errno will be set to the value + * after the failed I/O, or at the call to io_close(). */ -#define io_new_conn(fd, start, finish, arg) \ - io_new_conn_((fd), \ - 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_plan (*start)(struct io_conn *, void *), - void (*finish)(struct io_conn *, void *), - void *arg); +#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. * @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_plan, 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_plan (*start)(struct io_conn *, - void *arg), - void (*finish)(struct io_conn *, - void *arg), + void (*init)(int fd, void *arg), void *arg); /** @@ -126,13 +70,13 @@ struct io_listener *io_new_listener_(int fd, void io_close_listener(struct io_listener *listener); /** - * io_write - queue data to be written. + * io_write - plan to write data. * @data: the data buffer. * @len: the length to write. * @cb: function to call once it's done. * @arg: @cb argument * - * This will queue the data buffer for writing. Once it's all + * This creates a plan write out a data buffer. Once it's all * written, the @cb function will be called: on an error, the finish * function is called instead. * @@ -148,15 +92,15 @@ struct io_plan io_write_(const void *data, size_t len, void *arg); /** - * io_read - queue buffer to be read. + * io_read - plan to read data. * @data: the data buffer. * @len: the length to read. * @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 @cb function will be called: on an error, the finish function - * is called instead. + * This creates a plan to read data into a buffer. 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. */ @@ -171,13 +115,13 @@ struct io_plan io_read_(void *data, size_t len, /** - * io_read_partial - queue buffer to be read (partial OK). + * io_read_partial - plan to read some data. * @data: the data buffer. * @len: the maximum length to read, set to the length actually read. * @cb: function to call once it's done. * @arg: @cb argument * - * This will queue the data buffer for reading. Once any data is + * This creates a plan to read data into a buffer. Once any data is * read, @len is updated and the @cb function will be called: on an * error, the finish function is called instead. * @@ -193,13 +137,13 @@ struct io_plan io_read_partial_(void *data, size_t *len, void *arg); /** - * io_write_partial - queue data to be written (partial OK). + * io_write_partial - plan to write some data. * @data: the data buffer. * @len: the maximum length to write, set to the length actually written. * @cb: function to call once it's done. * @arg: @cb argument * - * This will queue the data buffer for writing. Once any data is + * This creates a plan to write data from a buffer. Once any data is * written, @len is updated and the @cb function will be called: on an * error, the finish function is called instead. * @@ -214,21 +158,19 @@ 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. + * io_idle - plan to do nothing. * - * 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. + * This indicates the connection is idle: io_wake() will be called later do + * give the connection a new plan. */ struct io_plan io_idle(void); /** - * io_timeout - set timeout function if the callback doesn't fire. + * io_timeout - set timeout function if the callback doesn't complete. * @conn: the current connection. * @ts: how long until the timeout should be called. - * @cb to call. + * @cb: callback to call. * @arg: argument to @cb. * * If the usual next callback is not called for this connection before @ts, @@ -250,82 +192,60 @@ bool io_timeout_(struct io_conn *conn, struct timespec ts, /** * 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. + * @plan: the first I/O function to call. * * 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 + * single fd, but io forces a linear call sequence. The solution 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); +#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); /** - * io_wake - wake up and idle connection. + * io_wake - wake up an idle connection. * @conn: an idle connection. - * @fn: the next function to call once queued IO is complete. - * @arg: the argument to @next. + * @plan: the next I/O plan for @conn. * - * This makes @conn run its @next function the next time around the - * io_loop(). + * This makes @conn ready to do I/O the next time around the io_loop(). */ -#define io_wake(conn, fn, arg) \ - io_wake_((conn), \ - typesafe_cb_preargs(struct io_plan, void *, \ - (fn), (arg), struct io_conn *), \ - (arg)) -void io_wake_(struct io_conn *conn, - struct io_plan (*fn)(struct io_conn *, void *), void *arg); +#define io_wake(conn, plan) (io_plan_other(), io_wake_((conn), (plan))) +void io_wake_(struct io_conn *conn, struct io_plan plan); /** * io_break - return from io_loop() * @ret: non-NULL value to return from io_loop(). - * @cb: function to call once on return - * @arg: @cb argument + * @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 @ret. * - * If io_loop() is called again, then @cb will be called. + * If io_loop() is called again, then @plan will be carried out. */ -#define io_break(ret, fn, arg) \ - io_break_((ret), \ - typesafe_cb_preargs(struct io_plan, void *, \ - (fn), (arg), struct io_conn *), \ - (arg)) -struct io_plan io_break_(void *ret, - struct io_plan (*fn)(struct io_conn *, void *), - void *arg); +#define io_break(ret, plan) (io_plan_other(), io_break_((ret), (plan))) +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.