/**
* @file
*
* @brief Inlined Routines in the Core Message Handler
*
* This include file contains the static inline implementation of all
* inlined routines in the Core Message Handler.
*/
/*
* COPYRIGHT (c) 1989-2009.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifndef _RTEMS_SCORE_COREMSGIMPL_H
#define _RTEMS_SCORE_COREMSGIMPL_H
#include <rtems/score/coremsg.h>
#include <rtems/score/status.h>
#include <rtems/score/chainimpl.h>
#include <rtems/score/threaddispatch.h>
#include <rtems/score/threadqimpl.h>
#include <limits.h>
#include <string.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @addtogroup RTEMSScoreMessageQueue
*/
/**@{**/
/**
* @brief Used when appending messages onto a message queue.
*
* This is the priority constant used when appending messages onto
* a message queue.
*/
#define CORE_MESSAGE_QUEUE_SEND_REQUEST INT_MAX
/**
* @brief Used when prepending messages onto a message queue.
*
* This is the priority constant used when prepending messages onto
* a message queue.
*/
#define CORE_MESSAGE_QUEUE_URGENT_REQUEST INT_MIN
/**
* @brief 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.
*/
typedef int CORE_message_queue_Submit_types;
/**
* @brief Initialize 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 @a the_message_queue
* based on the parameters passed.
*
* @param[in] the_message_queue points to the message queue to initialize
* @param[in] discipline the blocking discipline
* @param[in] maximum_pending_messages is the maximum number of messages
* that will be allowed to pend at any given time
* @param[in] maximum_message_size is the size of largest message that
* may be sent to this message queue instance
*
* @retval true if the message queue can be initialized. In general,
* false will only be returned if memory for the pending
* messages cannot be allocated.
*/
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
);
/**
* @brief Close 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 @a the_message_queue's task wait queue.
*
* @param[in] the_message_queue points to the message queue to close
* @param[in] queue_context The thread queue context used for
* _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().
*/
void _CORE_message_queue_Close(
CORE_message_queue_Control *the_message_queue,
Thread_queue_Context *queue_context
);
/**
* @brief Flush 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 @a the_message_queue's pending message queue. The
* number of messages flushed from the queue is returned.
*
* @param[in] the_message_queue points to the message queue to flush
* @param[in] queue_context The thread queue context with interrupts disabled.
*
* @retval This method returns the number of message pending messages flushed.
*/
uint32_t _CORE_message_queue_Flush(
CORE_message_queue_Control *the_message_queue,
Thread_queue_Context *queue_context
);
#if defined(FUNCTIONALITY_NOT_CURRENTLY_USED_BY_ANY_API)
/**
* @brief Flush waiting threads.
*
* This function flushes the threads which are blocked on
* @a the_message_queue's pending message queue. They are
* unblocked whether blocked sending or receiving. It returns
* the number of messages flushed from the queue.
*
* @param[in] the_message_queue points to the message queue to flush
* @retval number of messages flushed from the queue
*/
void _CORE_message_queue_Flush_waiting_threads(
CORE_message_queue_Control *the_message_queue
);
#endif
/**
* @brief Broadcast 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.
*
* @param[in] the_message_queue points to the message queue
* @param[in] buffer is the starting address of the message to broadcast
* @param[in] size is the size of the message being broadcast
* @param[out] count points to the variable that will contain the
* number of tasks that are sent this message
* @param[in] queue_context The thread queue context used for
* _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().
* @retval @a *count will contain the number of messages sent
* @retval indication of the successful completion or reason for failure
*/
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
);
/**
* @brief Submit 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.
*
* @param[in] the_message_queue points to the message queue
* @param[in] buffer is the starting address of the message to send
* @param[in] size is the size of the message being send
* @param[in] submit_type determines whether the message is prepended,
* appended, or enqueued in priority order.
* @param[in] wait indicates whether the calling thread is willing to block
* if the message queue is full.
* @param[in] queue_context The thread queue context used for
* _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().
* @retval indication of the successful completion or reason for failure
*/
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
);
/**
* @brief Size 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.
*
* @param[in] the_message_queue points to the message queue
* @param[in] buffer is the starting address of the message buffer to
* to be filled in with a message
* @param[in] size_p is a pointer to the size of the @a buffer and
* indicates the maximum size message that the caller can receive.
* @param[in] wait indicates whether the calling thread is willing to block
* if the message queue is empty.
* @param[in] queue_context The thread queue context used for
* _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().
*
* @retval indication of the successful completion or reason for failure.
* On success, the location pointed to @a size_p will contain the
* size of the received message.
*
* @note Returns message priority via return area in TCB.
*
* - INTERRUPT LATENCY:
* + available
* + wait
*/
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
);
/**
* @brief Insert 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.
*
* @param[in] the_message_queue points to the message queue
* @param[in] the_message is the message to enqueue
* @param[in] content_source the message content source
* @param[in] content_size the message content size in bytes
* @param[in] submit_type determines whether the message is prepended,
* appended, or enqueued in priority order.
*/
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
);
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
)
{
return _CORE_message_queue_Submit(
the_message_queue,
_Thread_Executing,
buffer,
size,
CORE_MESSAGE_QUEUE_SEND_REQUEST,
wait,
queue_context
);
}
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
)
{
return _CORE_message_queue_Submit(
the_message_queue,
_Thread_Executing,
buffer,
size,
CORE_MESSAGE_QUEUE_URGENT_REQUEST,
wait,
queue_context
);
}
RTEMS_INLINE_ROUTINE void _CORE_message_queue_Acquire(
CORE_message_queue_Control *the_message_queue,
Thread_queue_Context *queue_context
)
{
_Thread_queue_Acquire( &the_message_queue->Wait_queue, queue_context );
}
RTEMS_INLINE_ROUTINE void _CORE_message_queue_Acquire_critical(
CORE_message_queue_Control *the_message_queue,
Thread_queue_Context *queue_context
)
{
_Thread_queue_Acquire_critical( &the_message_queue->Wait_queue, queue_context );
}
RTEMS_INLINE_ROUTINE void _CORE_message_queue_Release(
CORE_message_queue_Control *the_message_queue,
Thread_queue_Context *queue_context
)
{
_Thread_queue_Release( &the_message_queue->Wait_queue, queue_context );
}
/**
* This routine copies the contents of the source message buffer
* to the destination message buffer.
*/
RTEMS_INLINE_ROUTINE void _CORE_message_queue_Copy_buffer (
const void *source,
void *destination,
size_t size
)
{
memcpy(destination, source, size);
}
/**
* This function allocates a message buffer from the inactive
* message buffer chain.
*/
RTEMS_INLINE_ROUTINE CORE_message_queue_Buffer_control *
_CORE_message_queue_Allocate_message_buffer (
CORE_message_queue_Control *the_message_queue
)
{
return (CORE_message_queue_Buffer_control *)
_Chain_Get_unprotected( &the_message_queue->Inactive_messages );
}
/**
* This routine frees a message buffer to the inactive
* message buffer chain.
*/
RTEMS_INLINE_ROUTINE void _CORE_message_queue_Free_message_buffer (
CORE_message_queue_Control *the_message_queue,
CORE_message_queue_Buffer_control *the_message
)
{
_Chain_Append_unprotected( &the_message_queue->Inactive_messages, &the_message->Node );
}
/**
* This function returns the priority of @a the_message.
*
* @note It encapsulates the optional behavior that message priority is
* disabled if no API requires it.
*/
RTEMS_INLINE_ROUTINE int _CORE_message_queue_Get_message_priority (
const CORE_message_queue_Buffer_control *the_message
)
{
#if defined(RTEMS_SCORE_COREMSG_ENABLE_MESSAGE_PRIORITY)
return the_message->priority;
#else
return 0;
#endif
}
/**
* This function removes the first message from the_message_queue
* and returns a pointer to it.
*/
RTEMS_INLINE_ROUTINE
CORE_message_queue_Buffer_control *_CORE_message_queue_Get_pending_message (
CORE_message_queue_Control *the_message_queue
)
{
return (CORE_message_queue_Buffer_control *)
_Chain_Get_unprotected( &the_message_queue->Pending_messages );
}
#if defined(RTEMS_SCORE_COREMSG_ENABLE_NOTIFICATION)
/**
* This function returns true if notification is enabled on this message
* queue and false otherwise.
*/
RTEMS_INLINE_ROUTINE bool _CORE_message_queue_Is_notify_enabled (
CORE_message_queue_Control *the_message_queue
)
{
return (the_message_queue->notify_handler != NULL);
}
#endif
/**
* This routine initializes the notification information for
* @a the_message_queue.
*/
#if defined(RTEMS_SCORE_COREMSG_ENABLE_NOTIFICATION)
RTEMS_INLINE_ROUTINE void _CORE_message_queue_Set_notify (
CORE_message_queue_Control *the_message_queue,
CORE_message_queue_Notify_Handler the_handler
)
{
the_message_queue->notify_handler = the_handler;
}
#else
/* turn it into nothing if not enabled */
#define _CORE_message_queue_Set_notify( the_message_queue, the_handler ) \
do { } while ( 0 )
#endif
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
)
{
Thread_Control *the_thread;
/*
* If there are pending messages, then there can't be threads
* waiting for us to send them a message.
*
* NOTE: This check is critical because threads can block on
* send and receive and this ensures that we are broadcasting
* the message to threads waiting to receive -- not to send.
*/
if ( the_message_queue->number_of_pending_messages != 0 ) {
return NULL;
}
/*
* There must be no pending messages if there is a thread waiting to
* receive a message.
*/
the_thread = _Thread_queue_First_locked(
&the_message_queue->Wait_queue,
the_message_queue->operations
);
if ( the_thread == NULL ) {
return NULL;
}
*(size_t *) the_thread->Wait.return_argument = size;
the_thread->Wait.count = (uint32_t) submit_type;
_CORE_message_queue_Copy_buffer(
buffer,
the_thread->Wait.return_argument_second.mutable_object,
size
);
_Thread_queue_Extract_critical(
&the_message_queue->Wait_queue.Queue,
the_message_queue->operations,
the_thread,
queue_context
);
return the_thread;
}
/** @} */
#ifdef __cplusplus
}
#endif
#endif
/* end of include file */
