event.h File Reference

an implementation of the publish/subscribe pattern More...

#include "list.h"

Go to the source code of this file.

Data Structures
struct	event
	event state More...
struct	event_handler
	event handler state More...

Macros
#define	EVENT_HANDLER_INIT(handler_fun)
	allows static initialization of an event_handler More...
#define	EVENT_INIT(event)   { .handlers = LIST_INIT((event).handlers) }
	allows static initialization of an event More...

Functions
int	event_handler_init (struct event_handler *handler, void(*fun)(struct event *, void *))
	initialize an event handler More...
int	event_init (struct event *evt)
	initialize a event More...
int	event_subscribe (struct event *evt, struct event_handler *handler)
	attach an event_handler to an event More...
int	event_unsubscribe (struct event *evt, struct event_handler *handler)
	detach an event_handler from an event More...
int	event_publish (struct event *evt, void *ctx)
	publish an event More...

Detailed Description

an implementation of the publish/subscribe pattern

depends on list.h

Macro Definition Documentation

EVENT_HANDLER_INIT

#define EVENT_HANDLER_INIT

(

handler_fun

)

Value:

{            \
    .element = (struct list_element){ NULL, NULL },  \
    .fun = handler_fun,                              \
    .evt = NULL,                                     \
    .flags = 0                                       \
}

allows static initialization of an event_handler

struct event_handler my_handler = EVENT_HANDLER_INIT(my_handler_fun);

EVENT_INIT

#define EVENT_INIT

(

event

)

{ .handlers = LIST_INIT((event).handlers) }

allows static initialization of an event

struct event my_event = EVENT_INIT(my_event);

Function Documentation

event_handler_init()

int event_handler_init	(	struct event_handler *	handler,
		void(*)(struct event *, void *)	fun
	)

initialize an event handler

Parameters

handler	pointer to event_handler
fun	a function to be called when the subscribed event is published

event_init()

int event_init

(

struct event *

evt

)

initialize a event

Parameters

evt	pointer to event

Returns

0 if successful

event_publish()

int event_publish	(	struct event *	evt,
		void *	ctx
	)

publish an event

all subscribed events will have their handler functions called in an unspecified order

See also

event_handler_init and event_subscribe

Parameters

evt	pointer to initialized event
ctx	pointer to context to pass to subscribed event_handler functions

Returns

0 if successful

event_subscribe()

int event_subscribe	(	struct event *	evt,
		struct event_handler *	handler
	)

attach an event_handler to an event

Note

if one subscribes to an event from within a handler for that event the newly subscribed handler won't be called until the next time that event is published

Parameters

evt	pointer to initialized event
handler	pointer to initialized event_handler

Returns

0 if successful

event_unsubscribe()

int event_unsubscribe	(	struct event *	evt,
		struct event_handler *	handler
	)

detach an event_handler from an event

Note

unsubscribing a handler from within that handler's callback function is undefined

Parameters

evt	pointer to initialized event
handler	pointer to initialized event_handler

Returns

0 if the handler was unsubscribed