event.c File Reference

Event handling operations. More...

#include <event.h>
#include <logging.h>
#include <scheduler.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>

Include dependency graph for event.c:

Go to the source code of this file.

Functions
event_loop_t *	event_loop_get ()
int	event_loop_put (event_loop_t *event_loop, event_t *e)
event_t *	event_loop_take (event_loop_t *event_loop)
event_t *	event_init (void(*func)(scheduler_t *, void *), void *arg, char *name, char *source_name, uint16_t source_line)
void	event_destroy (event_t *e)
	Free any memory associated with an event. More...
void	event_loop_destroy ()
	Frees any memory associated with the event queue. More...
void	event_signal_ext (void *func, void *args, char *name, char *s_name, uint16_t s_line)
int	event_loop_enter (scheduler_t *scheduler, void(*update_call)(scheduler_t *), void(*signal_call)(scheduler_t *))
	Enters the event loop. More...
void	event_loop_terminate ()
	Stops the event loop from executing. More...

Variables
event_loop_t	vl_singleton
int	el_created = 0

Detailed Description

Event handling operations.

Definition in file event.c.

Function Documentation

event_destroy()

void event_destroy

(

event_t *

e

)

Free any memory associated with an event.

Parameters

e	the event to destroy

Definition at line 165 of file event.c.

event_init()

event_t* event_init	(	void(*)(scheduler_t *, void *)	func,
		void *	arg,
		char *	name,
		char *	source_name,
		uint16_t	source_line
	)

Allocates and initializes a new event. An event consists of a function and the arguments for that function. The arguments for the function should be taken in by the function as a sinlge void* and then parsed inside the function. This interface provides a simple and generic interface for getting a function to be called within the main thread.

Parameters

func	the function to call when the event is executed
arg	the arguements for the function.
name	name of the event
source_name	source file name creating the event
source_line	line number of the source file creating the event

Returns

the new event wrapper for the function and arguments

Definition at line 147 of file event.c.

event_loop_destroy()

void event_loop_destroy

(

)

Frees any memory associated with the event queue.

Any events that are in the queue when this gets called will be freed as well.

Definition at line 179 of file event.c.

event_loop_enter()

int event_loop_enter	(	scheduler_t *	scheduler,
		void(*)(scheduler_t *)	update_call,
		void(*)(scheduler_t *)	signal_call
	)

Enters the event loop.

This function will not return until another threads chooses to terminate the event loop. Essentially this function should not return until the program is ready to exit. There should also only be one thread working on this part of the event loop.

Parameters

scheduler	scheduler reference to to be notified
update_call	a function that is called every time an event is processed
signal_call	a function that is called once a second

Returns

this function will return an error code: 0x0: successful execution 0x1: attempt to enter a loop that is occupied

Definition at line 221 of file event.c.

event_loop_get()

event_loop_t* event_loop_get

(

)

There is only one instance of an event loop in any program. This function will control access to that event loop. If the event loop hasn't been created yet, it will create and return the event loop. If it has been created, this function will simple return it to the caller. This first call to this function should be made from the thread that will be running the event loop.

This is to prevent confusion on if the event loop has been created.

Returns

Definition at line 48 of file event.c.

event_loop_put()

int event_loop_put	(	event_loop_t *	event_loop,
		event_t *	e
	)

puts a new item into the event queue. The event queue acts as a circular, concurrent queue, and as a result this function must correct synchronize on the queue to prevent race conditions. This will lock the queue, and wait if the queue is full.

Parameters

event_loop	the event loop to add the event to
e	the event to put into the event loop

Returns

true if the item was succesfully added, false otherwise

Definition at line 75 of file event.c.

event_loop_take()

event_t* event_loop_take

(

event_loop_t *

event_loop

)

Takes the next item out of the queue. The event queue acts as a circular, concurrent queue, and as a result this function must correctly synchronize on the queue to prevent race conditions. This will lock the queue, and wait if the queue is full.

Parameters

event_loop

the event loop to get the event out of

Returns

the next event in the event loop, NULL if the event loop has ended

Definition at line 90 of file event.c.

event_loop_terminate()

void event_loop_terminate

(

)

Stops the event loop from executing.

This will wake up any threads that are waiting on either a push into the event loop, or are trying to take from the event loop and the put() and take() functions will return errors.

Definition at line 275 of file event.c.

event_signal_ext()

void event_signal_ext	(	void *	func,
		void *	args,
		char *	name,
		char *	s_name,
		uint16_t	s_line
	)

public interface for creating new events. Simple call this function, with the first argument being a function pointer ( void(*)(void*) ) and the second being the arguments for the function.

Parameters

func
args
name	name of the event
s_name	source file name creating the event
s_line	line number of the source file creating the event

Definition at line 200 of file event.c.

Variable Documentation

el_created

int el_created = 0

Flag used to check if the event loop has been created

Definition at line 35 of file event.c.

vl_singleton

event_loop_t vl_singleton

The event loop is a singleton, this is the only actual event loop

Definition at line 29 of file event.c.