Flags

Functions
void	flags_clr (flags_t *flags, flags_mask_t mask)
flags_t *	flags_create (flags_value_t value)
void	flags_destroy (flags_t *flags)
flags_value_t	flags_get (flags_t *flags)
void	flags_set (flags_t *flags, flags_mask_t mask)
void	flags_wait_all (flags_t *flags, flags_mask_t mask, flags_value_t *value)
int	flags_wait_all_tmo (flags_t *flags, flags_mask_t mask, tick_t time, flags_mask_t *value)
void	flags_wait_any (flags_t *flags, flags_mask_t mask, flags_value_t *value)
int	flags_wait_any_tmo (flags_t *flags, flags_mask_t mask, tick_t time, flags_value_t *value)

---

Function Documentation

void flags_clr	(	flags_t *	flags,
		flags_mask_t	mask
	)

Clears the flag. Bits that are set to one in the mask are cleared in the flag register. Bits that are set to zero in the mask are left unmodified.

Parameters:

	flags	Flags handle
	mask	Mask value

flags_t* flags_create

(

flags_value_t

value

)

Allocates and initialises a flags handle. The flag register is initialised to value.

Parameters:

value

Initial value of flags

Returns:

The flags handle to be used in all subsequent operations on the flag.

void flags_destroy

(

flags_t *

flags

)

Frees the resources allocated by the flags. The flags must not be in use when this function is called (no task can be waiting on the flag, nor can they do so at any time after calling this function).

Parameters:

flags

Flags handle

flags_value_t flags_get

(

flags_t *

flags

)

Gets the value in the flag register.

Parameters:

flags

Flags handle

Returns:

The value in the flag register.

void flags_set	(	flags_t *	flags,
		flags_mask_t	mask
	)

Sets the flag. Bits that are set to one in the mask are set in the flag register. Bits that are set to zero in the mask are left unmodified.

If any tasks were waiting on any of the bits that were modified, they will be put in the READY state.

Parameters:

	flags	Flags handle
	mask	Mask value

void flags_wait_all	(	flags_t *	flags,
		flags_mask_t	mask,
		flags_value_t *	value
	)

Waits for all of the requested bits in the flag register to be set.

If all of the bits that are set to one in the mask are also set to one in the flag, then the function will return immediately. If any of the bits that are set to one in the mask are not set in the flag, then the calling task is put in the WAITING state.

Parameters:

	flags	Flags handle
	mask	Mask value
	value	Updated with value of flags after waiting

int flags_wait_all_tmo	(	flags_t *	flags,
		flags_mask_t	mask,
		tick_t	time,
		flags_mask_t *	value
	)

Analogous to flags_wait_all(), but a maximum time to wait can be specified. If any of the requested bits are not set, the calling task will wait until all of the requested bits become set, or the number of ticks given by time expires.

Parameters:

	flags	Flags handle
	mask	Mask value
	time	Number of ticks to wait
	value	Updated with value of flags after waiting

Returns:

0 if all of the requested bits are set, 1 if the service timed out.

void flags_wait_any	(	flags_t *	flags,
		flags_mask_t	mask,
		flags_value_t *	value
	)

Waits for any of the requested bits in the flag register to be set.

If any of the bits that are set to one in the mask are also set to one in the flag, then the function will return immediately. If none of the bits that are set to one in the mask are set in the flag, then the calling task is put in the WAITING state.

Parameters:

	flags	Flags handle
	mask	Mask value
	value	Updated with value of flag register after waiting

int flags_wait_any_tmo	(	flags_t *	flags,
		flags_mask_t	mask,
		tick_t	time,
		flags_value_t *	value
	)

Analogous to flags_wait_any(), but a maximum time to wait can be specified. If none of the requested bits are set, the calling task will wait until any of the requested bits become set, or the number of ticks given by time expires.

Parameters:

	flags	Flags handle
	mask	Mask value
	time	Number of ticks to wait
	value	Updated with value of flag register after waiting

Returns:

0 if any of the requested bits are set, 1 if the service timed out.