FreeRTOS_POSIX_timer.c File Reference

Implementation of timer functions in time.h. More...

#include <stddef.h>
#include "FreeRTOS_POSIX.h"
#include "FreeRTOS_POSIX/errno.h"
#include "FreeRTOS_POSIX/pthread.h"
#include "FreeRTOS_POSIX/signal.h"
#include "FreeRTOS_POSIX/time.h"
#include "FreeRTOS_POSIX/utils.h"
#include "timers.h"

Data Structures
struct	timer_internal_t
	Internal timer structure. More...

Macros
#define	TIMESPEC_IS_ZERO(xTimespec)   ( xTimespec.tv_sec == 0 && xTimespec.tv_nsec == 0 )
#define	TIMESPEC_IS_NOT_ZERO(xTimespec)   ( !( TIMESPEC_IS_ZERO( xTimespec ) ) )

Functions
void	prvTimerCallback (TimerHandle_t xOpaqueTimerHandle)
int	timer_create (clockid_t clockid, struct sigevent *evp, timer_t *timerid)
	Create a per-process timer. More...
int	timer_delete (timer_t timerid)
	Delete a per-process timer. More...
int	timer_getoverrun (timer_t timerid)
	Get the timer overrun count. More...
int	timer_settime (timer_t timerid, int flags, const struct itimerspec *value, struct itimerspec *ovalue)
	Set the time until the next expiration of the timer. More...
int	timer_gettime (timer_t timerid, struct itimerspec *value)
	Get the amount of time until the timer expires. More...

Detailed Description

Implementation of timer functions in time.h.

Macro Definition Documentation

TIMESPEC_IS_ZERO

#define TIMESPEC_IS_ZERO

(

xTimespec

)

( xTimespec.tv_sec == 0 && xTimespec.tv_nsec == 0 )

Check for 0.

TIMESPEC_IS_NOT_ZERO

#define TIMESPEC_IS_NOT_ZERO

(

xTimespec

)

( !( TIMESPEC_IS_ZERO( xTimespec ) ) )

Check for not 0.

Function Documentation

timer_create()

int timer_create	(	clockid_t	clockid,
		struct sigevent *	evp,
		timer_t *	timerid
	)

Create a per-process timer.

http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_create.html

Note

clock_id is ignored, as this function used the FreeRTOS tick count as its clock.

evp.sigev_notify must be set to SIGEV_THREAD, since signals are currently not supported.

Return values

0	- Upon successful completion, with location referenced by timerid updated.
-1	- If an error occurs. errno is also set.

Side Effects Possible errno values

ENOTSUP - If evp is NULL OR evp->sigen_notify == SIGEV_SIGNAL.
EAGAIN - The system lacks sufficient signal queuing resources to honor the request.

timer_delete()

int timer_delete

(

timer_t

timerid

)

Delete a per-process timer.

http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_delete.html

Return values

0	- Upon successful completion.

timer_getoverrun()

int timer_getoverrun

(

timer_t

timerid

)

Get the timer overrun count.

http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_getoverrun.html

Return values

0	- Always return 0, since signals are not supported.

timer_settime()

int timer_settime	(	timer_t	timerid,
		int	flags,
		const struct itimerspec *	value,
		struct itimerspec *	ovalue
	)

Set the time until the next expiration of the timer.

http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_settime.html

Return values

0	- Upon successful completion.
-1	- An error occurred, errno is also set.

Side Effects Possible errno values

EINVAL - A value structure specified a nanosecond value less than zero or greater than or equal to 1000 million, AND the it_value member of that structure did not specify zero seconds and nanoseconds.

timer_gettime()

int timer_gettime	(	timer_t	timerid,
		struct itimerspec *	value
	)

Get the amount of time until the timer expires.

http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_gettime.html

Return values

0	- Upon successful completion.