Message Queue Handler. More...

Files
file	coremsg.h
	Constants and Structures Associated with the Message Queue Handler.

file	coremsgimpl.h
	Inlined Routines in the Core Message Handler.

file	coremsg.c
	Initialize a Message Queue.

file	coremsgbroadcast.c
	Broadcast a Message to the Message Queue.

file	coremsgclose.c
	Close a Message Queue.

file	coremsgflush.c
	Flush Messages Routine.

file	coremsgflushwait.c
	Flush Waiting Threads.

file	coremsginsert.c
	Insert a Message into the Message Queue.

file	coremsgseize.c
	Seize a Message from the Message Queue.

file	coremsgsubmit.c
	CORE Message Queue Submit.

Data Structures
struct	CORE_message_queue_Buffer
	Data types needed to manipulate the contents of message buffers. More...

struct	CORE_message_queue_Buffer_control
	The organization of a message buffer. More...

struct	CORE_message_queue_Control
	Control block used to manage each message queue. More...

Macros
#define	RTEMS_SCORE_COREMSG_ENABLE_MESSAGE_PRIORITY

#define	RTEMS_SCORE_COREMSG_ENABLE_BLOCKING_SEND

#define	CORE_MESSAGE_QUEUE_SEND_REQUEST INT_MAX
	Used when appending messages onto a message queue. More...

#define	CORE_MESSAGE_QUEUE_URGENT_REQUEST INT_MIN
	Used when prepending messages onto a message queue. More...

#define	_CORE_message_queue_Set_notify(the_message_queue, the_handler) do { } while ( 0 )
	Initializes notification information. More...

Typedefs
typedef struct CORE_message_queue_Control	CORE_message_queue_Control

typedef int	CORE_message_queue_Submit_types
	The modes in which a message may be submitted to a message queue. More...

Enumerations
enum	CORE_message_queue_Disciplines { CORE_MESSAGE_QUEUE_DISCIPLINES_FIFO, CORE_MESSAGE_QUEUE_DISCIPLINES_PRIORITY }
	The possible blocking disciplines for a message queue. More...

Functions
bool	_CORE_message_queue_Initialize (CORE_message_queue_Control *the_message_queue, CORE_message_queue_Disciplines discipline, uint32_t maximum_pending_messages, size_t maximum_message_size)
	Initializes a message queue. More...

void	_CORE_message_queue_Close (CORE_message_queue_Control the_message_queue, Thread_queue_Context queue_context)
	Closes a message queue. More...

uint32_t	_CORE_message_queue_Flush (CORE_message_queue_Control the_message_queue, Thread_queue_Context queue_context)
	Flushes pending messages. More...

Status_Control	_CORE_message_queue_Broadcast (CORE_message_queue_Control the_message_queue, const void buffer, size_t size, uint32_t count, Thread_queue_Context queue_context)
	Broadcasts a message to the message queue. More...

Status_Control	_CORE_message_queue_Submit (CORE_message_queue_Control the_message_queue, Thread_Control executing, const void buffer, size_t size, CORE_message_queue_Submit_types submit_type, bool wait, Thread_queue_Context queue_context)
	Submits a message to the message queue. More...

Status_Control	_CORE_message_queue_Seize (CORE_message_queue_Control the_message_queue, Thread_Control executing, void buffer, size_t size_p, bool wait, Thread_queue_Context *queue_context)
	Seizes a message from the message queue. More...

void	_CORE_message_queue_Insert_message (CORE_message_queue_Control the_message_queue, CORE_message_queue_Buffer_control the_message, const void *content_source, size_t content_size, CORE_message_queue_Submit_types submit_type)
	Inserts a message into the message queue. More...

RTEMS_INLINE_ROUTINE Status_Control	_CORE_message_queue_Send (CORE_message_queue_Control the_message_queue, const void buffer, size_t size, bool wait, Thread_queue_Context *queue_context)
	Sends a message to the message queue. More...

RTEMS_INLINE_ROUTINE Status_Control	_CORE_message_queue_Urgent (CORE_message_queue_Control the_message_queue, const void buffer, size_t size, bool wait, Thread_queue_Context *queue_context)
	Sends an urgent message to the message queue. More...

RTEMS_INLINE_ROUTINE void	_CORE_message_queue_Acquire (CORE_message_queue_Control the_message_queue, Thread_queue_Context queue_context)
	Acquires the message queue. More...

RTEMS_INLINE_ROUTINE void	_CORE_message_queue_Acquire_critical (CORE_message_queue_Control the_message_queue, Thread_queue_Context queue_context)
	Acquires the message queue critical. More...

RTEMS_INLINE_ROUTINE void	_CORE_message_queue_Release (CORE_message_queue_Control the_message_queue, Thread_queue_Context queue_context)
	Releases the message queue. More...

RTEMS_INLINE_ROUTINE void	_CORE_message_queue_Copy_buffer (const void source, void destination, size_t size)
	Copies the source message buffer to the destination message buffer. More...

RTEMS_INLINE_ROUTINE CORE_message_queue_Buffer_control *	_CORE_message_queue_Allocate_message_buffer (CORE_message_queue_Control *the_message_queue)
	Allocates a message buffer from the inactive message buffer chain. More...

RTEMS_INLINE_ROUTINE void	_CORE_message_queue_Free_message_buffer (CORE_message_queue_Control the_message_queue, CORE_message_queue_Buffer_control the_message)
	Frees a message buffer to inactive message buffer chain. More...

RTEMS_INLINE_ROUTINE int	_CORE_message_queue_Get_message_priority (const CORE_message_queue_Buffer_control *the_message)
	Gets message priority. More...

RTEMS_INLINE_ROUTINE CORE_message_queue_Buffer_control *	_CORE_message_queue_Get_pending_message (CORE_message_queue_Control *the_message_queue)
	Gets first message of message queue and removes it. More...

RTEMS_INLINE_ROUTINE Thread_Control *	_CORE_message_queue_Dequeue_receiver (CORE_message_queue_Control the_message_queue, const void buffer, size_t size, CORE_message_queue_Submit_types submit_type, Thread_queue_Context *queue_context)
	Gets the first locked thread waiting to receive and dequeues it. More...

Detailed Description

Message Queue Handler.

This handler encapsulates functionality which provides the foundation Message Queue services used in all of the APIs supported by RTEMS.

Macro Definition Documentation

◆ _CORE_message_queue_Set_notify

#define _CORE_message_queue_Set_notify	(	the_message_queue,
		the_handler
	)	do { } while ( 0 )

Initializes notification information.

This routine initializes the notification information for the_message_queue.

Parameters

[out]	the_message_queue	The message queue to initialize the notification information.
[out]	the_handler	The notification information for the message queue.

◆ CORE_MESSAGE_QUEUE_SEND_REQUEST

#define CORE_MESSAGE_QUEUE_SEND_REQUEST INT_MAX

Used when appending messages onto a message queue.

This is the priority constant used when appending messages onto a message queue.

◆ CORE_MESSAGE_QUEUE_URGENT_REQUEST

#define CORE_MESSAGE_QUEUE_URGENT_REQUEST INT_MIN

Used when prepending messages onto a message queue.

This is the priority constant used when prepending messages onto a message queue.

◆ RTEMS_SCORE_COREMSG_ENABLE_BLOCKING_SEND

#define RTEMS_SCORE_COREMSG_ENABLE_BLOCKING_SEND

This macro is defined when an API is enabled that requires the Message Queue Handler include support for blocking send operations.

◆ RTEMS_SCORE_COREMSG_ENABLE_MESSAGE_PRIORITY

#define RTEMS_SCORE_COREMSG_ENABLE_MESSAGE_PRIORITY

This macro is defined when an API is enabled that requires that the Message Queue Handler include support for priority based enqueuing of messages.

Typedef Documentation

◆ CORE_message_queue_Submit_types

typedef int CORE_message_queue_Submit_types

The modes in which a message may be submitted to a message queue.

The following type details the modes in which a message may be submitted to a message queue. The message may be posted in a send or urgent fashion.

Note: All other values are message priorities. Numerically smaller priorities indicate higher priority messages.

Enumeration Type Documentation

◆ CORE_message_queue_Disciplines

enum CORE_message_queue_Disciplines

The possible blocking disciplines for a message queue.

This enumerated types defines the possible blocking disciplines for a message queue.

Enumerator
CORE_MESSAGE_QUEUE_DISCIPLINES_FIFO	This value indicates that blocking tasks are in FIFO order.
CORE_MESSAGE_QUEUE_DISCIPLINES_PRIORITY	This value indicates that blocking tasks are in priority order.

Function Documentation

◆ _CORE_message_queue_Acquire()

RTEMS_INLINE_ROUTINE void _CORE_message_queue_Acquire	(	CORE_message_queue_Control *	the_message_queue,
		Thread_queue_Context *	queue_context
	)

Acquires the message queue.

Parameters

[in,out]	the_message_queue	Rhe message queue to acquire.
	queue_context	The thread queue context.

◆ _CORE_message_queue_Acquire_critical()

RTEMS_INLINE_ROUTINE void _CORE_message_queue_Acquire_critical	(	CORE_message_queue_Control *	the_message_queue,
		Thread_queue_Context *	queue_context
	)

Acquires the message queue critical.

Parameters

[in,out]	the_message_queue	The message queue to acquire critical.
	queue_context	The thread queue context.

◆ _CORE_message_queue_Allocate_message_buffer()

RTEMS_INLINE_ROUTINE CORE_message_queue_Buffer_control* _CORE_message_queue_Allocate_message_buffer ( CORE_message_queue_Control * the_message_queue )

Allocates a message buffer from the inactive message buffer chain.

This function allocates a message buffer from the inactive message buffer chain.

Parameters

the_message_queue The message queue to operate upon.

Return values

pointer	The allocated message buffer.
NULL	The inactive message buffer chain is empty.

◆ _CORE_message_queue_Broadcast()

Status_Control _CORE_message_queue_Broadcast	(	CORE_message_queue_Control *	the_message_queue,
		const void *	buffer,
		size_t	size,
		uint32_t *	count,
		Thread_queue_Context *	queue_context
	)

Broadcasts a message to the message queue.

This package is the implementation of the CORE Message Queue Handler. This core object provides task synchronization and communication functions via messages passed to queue objects.

This function sends a message for every thread waiting on the queue and returns the number of threads made ready by the message.

Parameters

[in,out]	the_message_queue	The message queue to operate upon.
	buffer	The starting address of the message to broadcast.
	size	The size of the message being broadcast.
[out]	count	The variable that will contain the number of tasks that are sent this message.
	queue_context	The thread queue context used for _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().

Return values

STATUS_SUCCESSFUL	The message was successfully broadcast.
STATUS_MESSAGE_INVALID_SIZE	The message size was too big.

◆ _CORE_message_queue_Close()

void _CORE_message_queue_Close	(	CORE_message_queue_Control *	the_message_queue,
		Thread_queue_Context *	queue_context
	)

Closes a message queue.

This package is the implementation of the CORE Message Queue Handler. This core object provides task synchronization and communication functions via messages passed to queue objects.

This function closes a message by returning all allocated space and flushing the_message_queue's task wait queue.

Parameters

[in,out]	the_message_queue	The message queue to close.
[in,out]	queue_context	The thread queue context used for _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().

◆ _CORE_message_queue_Copy_buffer()

RTEMS_INLINE_ROUTINE void _CORE_message_queue_Copy_buffer	(	const void *	source,
		void *	destination,
		size_t	size
	)

Copies the source message buffer to the destination message buffer.

This routine copies the contents of the source message buffer to the destination message buffer.

Parameters

	source	The source message buffer to be copied.
[out]	destination	The destination messag buffer to copy the source to.
	size	The size of the source buffer.

◆ _CORE_message_queue_Dequeue_receiver()

RTEMS_INLINE_ROUTINE Thread_Control* _CORE_message_queue_Dequeue_receiver	(	CORE_message_queue_Control *	the_message_queue,
		const void *	buffer,
		size_t	size,
		CORE_message_queue_Submit_types	submit_type,
		Thread_queue_Context *	queue_context
	)

Gets the first locked thread waiting to receive and dequeues it.

This method dequeues the first locked thread waiting to receive a message, dequeues it and returns the corresponding Thread_Control.

Parameters

[in,out]	the_message_queue	The message queue to operate upon.
	buffer	The buffer that is copied to the threads mutable_object.
	size	The size of the buffer.
	submit_type	Indicates whether the thread should be willing to block in the future.
	queue_context	The thread queue context.

Return values

thread	The Thread_Control for the first locked thread, if there is a locked thread.
NULL	There are pending messages or no thread waiting to receive.

◆ _CORE_message_queue_Flush()

uint32_t _CORE_message_queue_Flush	(	CORE_message_queue_Control *	the_message_queue,
		Thread_queue_Context *	queue_context
	)

Flushes pending messages.

This package is the implementation of the CORE Message Queue Handler. This core object provides task synchronization and communication functions via messages passed to queue objects.

This function flushes the_message_queue's pending message queue. The number of messages flushed from the queue is returned.

Parameters

[in,out]	the_message_queue	The message queue to flush.
	queue_context	The thread queue context with interrupts disabled.

Returns: This method returns the number of message pending messages flushed.

◆ _CORE_message_queue_Free_message_buffer()

RTEMS_INLINE_ROUTINE void _CORE_message_queue_Free_message_buffer	(	CORE_message_queue_Control *	the_message_queue,
		CORE_message_queue_Buffer_control *	the_message
	)

Frees a message buffer to inactive message buffer chain.

This routine frees a message buffer to the inactive message buffer chain.

Parameters

[in,out]	the_message_queue	The message queue to free the message buffer to.
[out]	the_message	The message to be freed.

◆ _CORE_message_queue_Get_message_priority()

RTEMS_INLINE_ROUTINE int _CORE_message_queue_Get_message_priority ( const CORE_message_queue_Buffer_control * the_message )

Gets message priority.

This function returns the priority of the_message.

Parameters

the_message The message to obtain the priority from.

Return values

priority	The priority of this message.
0	Message priority is disabled.

Note: It encapsulates the optional behavior that message priority is disabled if no API requires it.

◆ _CORE_message_queue_Get_pending_message()

RTEMS_INLINE_ROUTINE CORE_message_queue_Buffer_control* _CORE_message_queue_Get_pending_message ( CORE_message_queue_Control * the_message_queue )

Gets first message of message queue and removes it.

This function removes the first message from the_message_queue and returns a pointer to it.

Parameters

[in,out] the_message_queue The message queue to get the first message from.

Return values

pointer	The first message if the message queue is not empty.
NULL	The message queue is empty.

◆ _CORE_message_queue_Initialize()

bool _CORE_message_queue_Initialize	(	CORE_message_queue_Control *	the_message_queue,
		CORE_message_queue_Disciplines	discipline,
		uint32_t	maximum_pending_messages,
		size_t	maximum_message_size
	)

Initializes a message queue.

This package is the implementation of the CORE Message Queue Handler. This core object provides task synchronization and communication functions via messages passed to queue objects.

This routine initializes the_message_queue based on the parameters passed.

Parameters

[out]	the_message_queue	The message queue to initialize.
	discipline	The blocking discipline for the message queue.
	maximum_pending_messages	The maximum number of messages that will be allowed to pend at any given time.
	maximum_message_size	The size of the largest message that may be sent to this message queue instance.

Return values

true	The message queue can be initialized.
false	Memory for the pending messages cannot be allocated.

◆ _CORE_message_queue_Insert_message()

void _CORE_message_queue_Insert_message	(	CORE_message_queue_Control *	the_message_queue,
		CORE_message_queue_Buffer_control *	the_message,
		const void *	content_source,
		size_t	content_size,
		CORE_message_queue_Submit_types	submit_type
	)

Inserts a message into the message queue.

Copies the specified content into the message storage space and then inserts the message into the message queue according to the submit type.

Parameters

[in,out]	the_message_queue	The message queue to insert a message in.
[in,out]	the_message	The message to insert in the message queue.
	content_source	The message content source.
	content_size	The message content size in bytes.
	submit_type	Determines whether the message is prepended, appended, or enqueued in priority order.

◆ _CORE_message_queue_Release()

RTEMS_INLINE_ROUTINE void _CORE_message_queue_Release	(	CORE_message_queue_Control *	the_message_queue,
		Thread_queue_Context *	queue_context
	)

Releases the message queue.

Parameters

[in,out]	the_message_queue	The message queue to release.
	queue_context	The thread queue context.

◆ _CORE_message_queue_Seize()

Status_Control _CORE_message_queue_Seize	(	CORE_message_queue_Control *	the_message_queue,
		Thread_Control *	executing,
		void *	buffer,
		size_t *	size_p,
		bool	wait,
		Thread_queue_Context *	queue_context
	)

Seizes a message from the message queue.

This package is the implementation of the CORE Message Queue Handler. This core object provides task synchronization and communication functions via messages passed to queue objects.

This kernel routine dequeues a message, copies the message buffer to a given destination buffer, and frees the message buffer to the inactive message pool. The thread will be blocked if wait is true, otherwise an error will be given to the thread if no messages are available.

Parameters

[in,out]	the_message_queue	The message queue to seize a message from.
	executing	The executing thread.
[out]	buffer	The starting address of the message buffer to to be filled in with a message.
[out]	size_p	The size of the buffer, indicates the maximum size message that the caller can receive.
	wait	Indicates whether the calling thread is willing to block if the message queue is empty.
	queue_context	The thread queue context used for _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().

Return values

STATUS_SUCCESSFUL	The message was successfully seized from the message queue.
STATUS_UNSATISFIED	Wait was set to false and there is currently no pending message.
STATUS_TIMEOUT	A timeout occured.

Note: Returns message priority via return area in TCB.

INTERRUPT LATENCY:
- available
- wait

◆ _CORE_message_queue_Send()

RTEMS_INLINE_ROUTINE Status_Control _CORE_message_queue_Send	(	CORE_message_queue_Control *	the_message_queue,
		const void *	buffer,
		size_t	size,
		bool	wait,
		Thread_queue_Context *	queue_context
	)

Sends a message to the message queue.

Parameters

[in,out]	the_message_queue	The message queue to send a message to.
	buffer	The starting address of the message to send.
	sizeis	The size of the message being send.
	wait	Indicates whether the calling thread is willing to block if the message queue is full.
	queue_context	The thread queue context used for _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().

Return values

STATUS_SUCCESSFUL	The message was successfully submitted to the message queue.
STATUS_MESSAGE_INVALID_SIZE	The message size was too big.
STATUS_TOO_MANY	No message buffers were available.
STATUS_MESSAGE_QUEUE_WAIT_IN_ISR	The caller is in an ISR, do not block!
STATUS_TIMEOUT	A timeout occured.

◆ _CORE_message_queue_Submit()

Status_Control _CORE_message_queue_Submit	(	CORE_message_queue_Control *	the_message_queue,
		Thread_Control *	executing,
		const void *	buffer,
		size_t	size,
		CORE_message_queue_Submit_types	submit_type,
		bool	wait,
		Thread_queue_Context *	queue_context
	)

Submits a message to the message queue.

This routine implements the send and urgent message functions. It processes a message that is to be submitted to the designated message queue. The message will either be processed as a send message which it will be inserted at the rear of the queue or it will be processed as an urgent message which will be inserted at the front of the queue.

Parameters

[in,out]	the_message_queue	The message queue to operate upon.
	executing	The executing thread.
	buffer	The starting address of the message to send.
	size	The size of the message being send.
	submit_type	Determines whether the message is prepended, appended, or enqueued in priority order.
	wait	Indicates whether the calling thread is willing to block if the message queue is full.
	queue_context	The thread queue context used for _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().

Return values

STATUS_SUCCESSFUL	The message was successfully submitted to the message queue.
STATUS_MESSAGE_INVALID_SIZE	The message size was too big.
STATUS_TOO_MANY	No message buffers were available.
STATUS_MESSAGE_QUEUE_WAIT_IN_ISR	The caller is in an ISR, do not block!
STATUS_TIMEOUT	A timeout occured.

◆ _CORE_message_queue_Urgent()

RTEMS_INLINE_ROUTINE Status_Control _CORE_message_queue_Urgent	(	CORE_message_queue_Control *	the_message_queue,
		const void *	buffer,
		size_t	size,
		bool	wait,
		Thread_queue_Context *	queue_context
	)

Sends an urgent message to the message queue.

Parameters

[in,out]	the_message_queue	The message queue to send an urgent message to.
	buffer	The starting address of the message to send.
	sizeis	The size of the message being send.
	wait	Indicates whether the calling thread is willing to block if the message queue is full.
	queue_context	The thread queue context used for _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().

Return values

STATUS_SUCCESSFUL	The message was successfully submitted to the message queue.
STATUS_MESSAGE_INVALID_SIZE	The message size was too big.
STATUS_TOO_MANY	No message buffers were available.
STATUS_MESSAGE_QUEUE_WAIT_IN_ISR	The caller is in an ISR, do not block!
STATUS_TIMEOUT	A timeout occured.

Files

Data Structures

Macros

Typedefs

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ _CORE_message_queue_Set_notify

◆ CORE_MESSAGE_QUEUE_SEND_REQUEST

◆ CORE_MESSAGE_QUEUE_URGENT_REQUEST

◆ RTEMS_SCORE_COREMSG_ENABLE_BLOCKING_SEND

◆ RTEMS_SCORE_COREMSG_ENABLE_MESSAGE_PRIORITY

Typedef Documentation

◆ CORE_message_queue_Submit_types

Enumeration Type Documentation

◆ CORE_message_queue_Disciplines

Function Documentation

◆ _CORE_message_queue_Acquire()

◆ _CORE_message_queue_Acquire_critical()

◆ _CORE_message_queue_Allocate_message_buffer()

◆ _CORE_message_queue_Broadcast()

◆ _CORE_message_queue_Close()

◆ _CORE_message_queue_Copy_buffer()

◆ _CORE_message_queue_Dequeue_receiver()

◆ _CORE_message_queue_Flush()

◆ _CORE_message_queue_Free_message_buffer()

◆ _CORE_message_queue_Get_message_priority()

◆ _CORE_message_queue_Get_pending_message()

◆ _CORE_message_queue_Initialize()

◆ _CORE_message_queue_Insert_message()

◆ _CORE_message_queue_Release()

◆ _CORE_message_queue_Seize()

◆ _CORE_message_queue_Send()

◆ _CORE_message_queue_Submit()

◆ _CORE_message_queue_Urgent()