RTEMS CPU Kit with SuperCore  4.10.99.0
Modules | Functions
Message Queues
RTEMS Classic API

Message Queue Manager. More...

Collaboration diagram for Message Queues:

Modules

 Classic Message Queue Implementation

Functions

rtems_status_code rtems_message_queue_create (rtems_name name, uint32_t count, size_t max_message_size, rtems_attribute attribute_set, rtems_id *id)
 RTEMS Create Message Queue.
rtems_status_code rtems_message_queue_ident (rtems_name name, uint32_t node, rtems_id *id)
 RTEMS Message Queue Name to Id.
rtems_status_code rtems_message_queue_delete (rtems_id id)
 RTEMS Delete Message Queue.
rtems_status_code rtems_message_queue_send (rtems_id id, const void *buffer, size_t size)
 rtems_message_queue_send
rtems_status_code rtems_message_queue_urgent (rtems_id id, const void *buffer, size_t size)
 RTEMS Urgent Message Queue.
rtems_status_code rtems_message_queue_broadcast (rtems_id id, const void *buffer, size_t size, uint32_t *count)
 RTEMS Broadcast Message Queue.
rtems_status_code rtems_message_queue_receive (rtems_id id, void *buffer, size_t *size, rtems_option option_set, rtems_interval timeout)
 RTEMS Message Queue Receive.
rtems_status_code rtems_message_queue_flush (rtems_id id, uint32_t *count)
 rtems_message_queue_flush
rtems_status_code rtems_message_queue_get_number_pending (rtems_id id, uint32_t *count)
 RTEMS Message Queue Get Number Pending.

Detailed Description

Message Queue Manager.

This encapsulates functionality related to the Classic API Message Queue Manager.

This include file contains all the constants and structures associated with the Message Queue Manager. This manager provides a mechanism for communication and synchronization between tasks using messages.

Directives provided are:


Function Documentation

rtems_status_code rtems_message_queue_broadcast ( rtems_id  id,
const void *  buffer,
size_t  size,
uint32_t *  count 
)

RTEMS Broadcast Message Queue.

This routine implements the rtems_message_queue_broadcast directive. This directive sends the message buffer to all of the tasks blocked waiting for a message on the message queue indicated by ID. If no tasks are waiting, then the message buffer will not be queued.

Parameters:
[in]idis the pointer to message queue
[in]bufferis the pointer to message buffer
[in]sizeis the size of message to broadcast
[in]countpointer to area to store number of threads made ready
Return values:
RTEMS_SUCCESSFULif successful or error code if unsuccessful and *count filled in with number of threads made ready
rtems_status_code rtems_message_queue_create ( rtems_name  name,
uint32_t  count,
size_t  max_message_size,
rtems_attribute  attribute_set,
rtems_id id 
)

RTEMS Create Message Queue.

This routine implements the rtems_message_queue_create directive. The message queue will have the name. If the attribute_set indicates that the message queue is to be limited in the number of messages that can be outstanding, then count indicates the maximum number of messages that will be held. It returns the id of the created message queue in id.

Parameters:
[in]nameis the user defined queue name
[in]countis the maximum message and reserved buffer count
[in]max_message_sizeis the maximum size of each message
[in]attribute_setis the process method
[in]idis the pointer to queue
Return values:
Thismethod returns RTEMS_SUCCESSFUL if there was not an error. Otherwise, a status code is returned indicating the source of the error. If successful, the id will be filled in with the queue id.
rtems_status_code rtems_message_queue_delete ( rtems_id  id)

RTEMS Delete Message Queue.

This routine implements the rtems_message_queue_delete directive. The message queue indicated by ID is deleted.

Parameters:
[in]idis the queue id
Return values:
RTEMS_SUCCESSFULif successful or error code if unsuccessful
rtems_status_code rtems_message_queue_flush ( rtems_id  id,
uint32_t *  count 
)

rtems_message_queue_flush

This routine implements the rtems_message_queue_flush directive. This directive takes all outstanding messages for the message queue indicated by ID and returns them to the inactive message chain. The number of messages flushed is returned in COUNT.

Message Queue Manager

rtems_status_code rtems_message_queue_get_number_pending ( rtems_id  id,
uint32_t *  count 
)

RTEMS Message Queue Get Number Pending.

Message Queue Manager

This routine implements the rtems_message_queue_get_number_pending directive. This directive returns the number of pending messages for the message queue indicated by ID chain. The number of messages pending is returned in COUNT.

rtems_status_code rtems_message_queue_ident ( rtems_name  name,
uint32_t  node,
rtems_id id 
)

RTEMS Message Queue Name to Id.

This routine implements the rtems_message_queue_ident directive. This directive returns the message queue ID associated with NAME. If more than one message queue is named name, then the message queue to which the ID belongs is arbitrary. node indicates the extent of the search for the ID of the message queue named name. The search can be limited to a particular node or allowed to encompass all nodes.

Parameters:
[in]nameis the user defined message queue name
[in]nodeis the node(s) to be searched
[in]idis the pointer to message queue id
Return values:
RTEMS_SUCCESSFULif successful or error code if unsuccessful and *id filled with the message queue id
rtems_status_code rtems_message_queue_receive ( rtems_id  id,
void *  buffer,
size_t *  size,
rtems_option  option_set,
rtems_interval  timeout 
)

RTEMS Message Queue Receive.

This routine implements the rtems_message_queue_receive directive. This directive is invoked when the calling task wishes to receive a message from the message queue indicated by ID. The received message is to be placed in buffer. If no messages are outstanding and the option_set indicates that the task is willing to block, then the task will be blocked until a message arrives or until, optionally, timeout clock ticks have passed.

Parameters:
[in]idis the queue id
[in]bufferis the pointer to message buffer
[in]sizeis the size of message receive
[in]option_setis the options on receive
[in]timeoutis the number of ticks to wait
Return values:
Thismethod returns RTEMS_SUCCESSFUL if there was not an error. Otherwise, a status code is returned indicating the source of the error.
rtems_status_code rtems_message_queue_send ( rtems_id  id,
const void *  buffer,
size_t  size 
)

rtems_message_queue_send

Message Queue Manager - rtems_message_queue_send

This routine implements the rtems_message_queue_send directive. This directive sends the message buffer to the message queue indicated by ID. If one or more tasks is blocked waiting to receive a message from this message queue, then one will receive the message. The task selected to receive the message is based on the task queue discipline algorithm in use by this particular message queue. If no tasks are waiting, then the message buffer will be placed at the REAR of the chain of pending messages for this message queue.

rtems_status_code rtems_message_queue_urgent ( rtems_id  id,
const void *  buffer,
size_t  size 
)

RTEMS Urgent Message Queue.

This routine implements the rtems_message_queue_urgent directive. This directive has the same behavior as rtems_message_queue_send except that if no tasks are waiting, the message buffer will be placed at the FRONT of the chain of pending messages rather than at the REAR.

Parameters:
[in]idis the pointer to message queue
[in]bufferis the pointer to message buffer
[in]sizeis the size of message to send urgently
Return values:
RTEMS_SUCCESSFULif successful or error code if unsuccessful