#include <ccan/time/time.h>
#include <stdbool.h>
#include <unistd.h>
-
-struct io_conn;
-
-/**
- * struct io_plan - returned from a setup function.
- *
- * A plan of what IO to do, when.
- */
-struct io_plan {
- int pollflag;
- /* Only NULL if idle. */
- int (*io)(int fd, struct io_plan *plan);
- /* Only NULL if closing. */
- struct io_plan (*next)(struct io_conn *, void *arg);
- void *next_arg;
-
- union {
- struct {
- char *buf;
- size_t len;
- } read;
- struct {
- const char *buf;
- size_t len;
- } write;
- struct {
- char *buf;
- size_t *lenp;
- } readpart;
- struct {
- const char *buf;
- size_t *lenp;
- } writepart;
- struct {
- int saved_errno;
- } close;
- struct {
- void *p;
- size_t len;
- } ptr_len;
- struct {
- void *p1;
- void *p2;
- } ptr_ptr;
- struct {
- size_t len1;
- size_t len2;
- } len_len;
- } u;
-};
-
-#ifdef DEBUG
-extern bool io_plan_for_other;
-extern bool (*io_debug)(struct io_conn *conn);
-#define io_plan_other() ((io_plan_for_other = true))
-void io_plan_debug(struct io_plan *plan);
-#else
-#define io_plan_other() (void)0
-static inline void io_plan_debug(struct io_plan *plan) { }
-#endif
+#include "io_plan.h"
/**
* io_new_conn - create a new connection.
* @fd: the file descriptor.
- * @plan: the first I/O function.
+ * @plan: the first I/O to perform.
*
* This creates a connection which owns @fd. @plan will be called on the
* next io_loop().
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.
*
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.
*/
/**
- * 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.
*
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.
*
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,
* @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.
*
*/
#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 an idle connection.
* @conn: an idle connection.
- * @plan: the next I/O function for @conn.
+ * @plan: the next I/O plan for @conn.
*
- * This makes @conn do I/O 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, plan) (io_plan_other(), io_wake_((conn), (plan)))
void io_wake_(struct io_conn *conn, struct io_plan plan);
--- /dev/null
+/* Licensed under LGPLv2.1+ - see LICENSE file for details */
+#ifndef CCAN_IO_PLAN_H
+#define CCAN_IO_PLAN_H
+struct io_conn;
+
+/**
+ * struct io_plan - a plan of what I/O to do.
+ * @pollflag: POLLIN or POLLOUT.
+ * @io: function to call when fd is available for @pollflag.
+ * @next: function to call after @io returns true.
+ * @next_arg: argument to @next.
+ * @u: scratch area for I/O.
+ *
+ * When the fd is POLLIN or POLLOUT (according to @pollflag), @io is
+ * called. If it returns -1, io_close() becomed the new plan (and errno
+ * is saved). If it returns 1, @next is called, otherwise @io is
+ * called again when @pollflag is available.
+ *
+ * You can use this to write your own io_plan functions.
+ */
+struct io_plan {
+ int pollflag;
+ /* Only NULL if idle. */
+ int (*io)(int fd, struct io_plan *plan);
+ /* Only NULL if closing. */
+ struct io_plan (*next)(struct io_conn *, void *arg);
+ void *next_arg;
+
+ union {
+ struct {
+ char *buf;
+ size_t len;
+ } read;
+ struct {
+ const char *buf;
+ size_t len;
+ } write;
+ struct {
+ char *buf;
+ size_t *lenp;
+ } readpart;
+ struct {
+ const char *buf;
+ size_t *lenp;
+ } writepart;
+ struct {
+ int saved_errno;
+ } close;
+ struct {
+ void *p;
+ size_t len;
+ } ptr_len;
+ struct {
+ void *p1;
+ void *p2;
+ } ptr_ptr;
+ struct {
+ size_t len1;
+ size_t len2;
+ } len_len;
+ } u;
+};
+
+#ifdef DEBUG
+/**
+ * io_debug - routine to select connection(s) to debug.
+ *
+ * If this is set, the routine should return true if the connection is a
+ * debugging candidate. If so, the callchain for I/O operations on this
+ * connection will be linear, for easier use of a debugger.
+ */
+extern bool (*io_debug)(struct io_conn *conn);
+
+/**
+ * io_plan_other - mark the next plan not being for the current connection
+ *
+ * Most routines which take a plan are about to apply it to the current
+ * connection. We (ab)use this pattern for debugging: as soon as such a
+ * plan is created, it is called, to create a linear call chain.
+ *
+ * Some routines, like io_break() and io_wake() take an io_plan, but they
+ * must not be applied immediately to the current connection, so we call this
+ * first.
+ */
+#define io_plan_other() ((io_plan_for_other = true))
+
+/**
+ * io_plan_debug - hook for debugging a plan.
+ *
+ * After constructing a plan, call this. If the current connection is being
+ * debugged, then it will be immediately serviced with this plan.
+ */
+void io_plan_debug(struct io_plan *plan);
+extern bool io_plan_for_other;
+#else
+#define io_plan_other() (void)0
+static inline void io_plan_debug(struct io_plan *plan) { }
+#endif
+
+#endif /* CCAN_IO_PLAN_H */
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