#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 {
	IO_NOTIFY_ADDED,
	IO_NOTIFY_NOTFOUND,
	IO_NOTIFY_DISABLED
};

typedef void io_callback_t(void *context);
typedef void timeout_callback_t(void *context);

/* 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 timezone ioloop_timezone;

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,
		  io_callback_t *callback, void *context);
#define io_add(fd, condition, callback, context) \
	CONTEXT_CALLBACK(io_add, io_callback_t, \
			 callback, context, fd, condition)
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);

/* Timeout handlers */
struct timeout *timeout_add(unsigned int msecs, timeout_callback_t *callback,
			    void *context);
#define timeout_add(msecs, callback, context) \
	CONTEXT_CALLBACK(timeout_add, timeout_callback_t, \
			 callback, context, msecs)
/* Remove timeout handler, and set timeout pointer to NULL. */
void timeout_remove(struct timeout **timeout);

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);
/* Destroy I/O loop and set ioloop pointer to NULL. */
void io_loop_destroy(struct ioloop **ioloop);

#endif