ioloop.h revision a23a481f9dfd5f14ebf2768b51b6fbc1cce1c864
#ifndef IOLOOP_H
#define IOLOOP_H
#include <sys/time.h>
#include <time.h>
struct io;
struct timeout;
struct ioloop;
enum io_condition {
IO_READ = 0x01,
IO_WRITE = 0x02,
/* IO_ERROR can be used to check when writable pipe's reader side
closes the pipe. For other uses IO_READ should work just as well. */
IO_ERROR = 0x04,
/* internal */
IO_NOTIFY = 0x08
};
enum io_notify_result {
/* Notify added successfully */
IO_NOTIFY_ADDED,
/* Specified file doesn't exist, can't wait on it */
IO_NOTIFY_NOTFOUND,
/* Can't add notify for specified file. Main reasons for this:
a) No notify support at all, b) Only directory notifies supported */
IO_NOTIFY_NOSUPPORT
};
typedef void io_callback_t(void *context);
typedef void timeout_callback_t(void *context);
typedef void io_loop_time_moved_callback_t(time_t old_time, time_t new_time);
/* Time when the I/O loop started calling handlers.
Can be used instead of time(NULL). */
extern time_t ioloop_time;
extern struct timeval ioloop_timeval;
extern struct ioloop *current_ioloop;
/* You can create different handlers for IO_READ and IO_WRITE. IO_READ and
IO_ERROR can't use different handlers (and there's no point anyway).
Don't try to add multiple handlers for the same type. It's not checked and
the behavior will be undefined. */
struct io *io_add(int fd, enum io_condition condition,
unsigned int source_linenum,
io_callback_t *callback, void *context);
#define io_add(fd, condition, callback, context) \
CONTEXT_CALLBACK(io_add, io_callback_t, \
callback, context, fd, condition, __LINE__)
enum io_notify_result io_add_notify(const char *path, io_callback_t *callback,
void *context, struct io **io_r);
#ifdef CONTEXT_TYPE_SAFETY
# define io_add_notify(path, callback, context, io_r) \
({(void)(1 ? 0 : callback(context)); \
io_add_notify(path, (io_callback_t *)callback, context, io_r); })
#else
# define io_add_notify(path, callback, context, io_r) \
io_add_notify(path, (io_callback_t *)callback, context, io_r)
#endif
/* Remove I/O handler, and set io pointer to NULL. */
void io_remove(struct io **io);
/* Like io_remove(), but assume that the file descriptor is already closed.
With some backends this simply frees the memory. */
void io_remove_closed(struct io **io);
/* Timeout handlers */
struct timeout *timeout_add(unsigned int msecs, unsigned int source_linenum,
timeout_callback_t *callback, void *context);
#define timeout_add(msecs, callback, context) \
CONTEXT_CALLBACK(timeout_add, timeout_callback_t, \
callback, context, msecs, __LINE__)
/* Remove timeout handler, and set timeout pointer to NULL. */
void timeout_remove(struct timeout **timeout);
/* Reset timeout so it's next run after now+msecs. */
void timeout_reset(struct timeout *timeout);
/* Refresh ioloop_time and ioloop_timeval variables. */
void io_loop_time_refresh(void);
void io_loop_run(struct ioloop *ioloop);
void io_loop_stop(struct ioloop *ioloop); /* safe to run in signal handler */
bool io_loop_is_running(struct ioloop *ioloop);
/* call these if you wish to run the iteration only once */
void io_loop_set_running(struct ioloop *ioloop);
void io_loop_handler_run(struct ioloop *ioloop);
struct ioloop *io_loop_create(void);
/* Specify the maximum number of fds we're expecting to use. */
void io_loop_set_max_fd_count(struct ioloop *ioloop, unsigned int max_fds);
/* Destroy I/O loop and set ioloop pointer to NULL. */
void io_loop_destroy(struct ioloop **ioloop);
/* If time moves backwards or jumps forwards call the callback. */
void io_loop_set_time_moved_callback(struct ioloop *ioloop,
io_loop_time_moved_callback_t *callback);
/* Change the current_ioloop. */
void io_loop_set_current(struct ioloop *ioloop);
/* This context is used for all further I/O and timeout callbacks that are
added until returning to ioloop. When a callback is called, this context is
again activated. */
struct ioloop_context *io_loop_context_new(struct ioloop *ioloop);
void io_loop_context_ref(struct ioloop_context *ctx);
void io_loop_context_unref(struct ioloop_context **ctx);
/* Call the activate callback when this context is activated (I/O callback is
about to be called), and the deactivate callback when the context is
deactivated (I/O callback has returned). You can add multiple callbacks. */
void io_loop_context_add_callbacks(struct ioloop_context *ctx,
io_callback_t *activate,
io_callback_t *deactivate, void *context);
/* Remove callbacks with the given callbacks and context. */
void io_loop_context_remove_callbacks(struct ioloop_context *ctx,
io_callback_t *activate,
io_callback_t *deactivate, void *context);
/* Returns the current context set to ioloop. */
struct ioloop_context *io_loop_get_current_context(struct ioloop *ioloop);
/* Move the given I/O into the current I/O loop if it's not already
there. New I/O is returned, while the old one is freed. */
struct io *io_loop_move_io(struct io **io);
/* Like io_loop_move_io(), but for timeouts. */
struct timeout *io_loop_move_timeout(struct timeout **timeout);
#endif