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Diffstat (limited to 'cpukit/score/include/rtems/score/coremsg.h')
| -rw-r--r-- | cpukit/score/include/rtems/score/coremsg.h | 451 |
1 files changed, 451 insertions, 0 deletions
diff --git a/cpukit/score/include/rtems/score/coremsg.h b/cpukit/score/include/rtems/score/coremsg.h new file mode 100644 index 0000000000..4a93f6de25 --- /dev/null +++ b/cpukit/score/include/rtems/score/coremsg.h @@ -0,0 +1,451 @@ +/** + * @file rtems/score/coremsg.h + * + * This include file contains all the constants and structures associated + * with the Message queue 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.com/license/LICENSE. + * + * $Id$ + */ + +#ifndef _RTEMS_SCORE_COREMSG_H +#define _RTEMS_SCORE_COREMSG_H + +/** + * @defgroup ScoreMessageQueue Message Queue Handler + * + * This handler encapsulates functionality which provides the foundation + * Message Queue services used in all of the APIs supported by RTEMS. + */ +/**@{*/ + +#include <limits.h> +#include <rtems/score/thread.h> +#include <rtems/score/threadq.h> +#include <rtems/score/priority.h> +#include <rtems/score/watchdog.h> + +#if defined(RTEMS_POSIX_API) + #define RTEMS_SCORE_COREMSG_ENABLE_MESSAGE_PRIORITY +#endif + +#if defined(RTEMS_POSIX_API) + #define RTEMS_SCORE_COREMSG_ENABLE_NOTIFICATION +#endif + +#if defined(RTEMS_POSIX_API) + #define RTEMS_SCORE_COREMSG_ENABLE_BLOCKING_SEND +#endif + +#ifdef __cplusplus +extern "C" { +#endif + +/** + * @brief Message Queue MP Callback Prototype + * + * The following type defines the callout which the API provides + * to support global/multiprocessor operations on message_queues. + */ +typedef void ( *CORE_message_queue_API_mp_support_callout )( + Thread_Control *, + Objects_Id + ); + +/** + * @brief Message Buffer Contents Management Structure + * + * The following defines the data types needed to manipulate + * the contents of message buffers. + * + * @note The buffer field is normally longer than a single uint32_t + * but since messages are variable length we just make a ptr to 1. + */ +typedef struct { + /** This field is the size of this message. */ + size_t size; + /** This field contains the actual message. */ + uint32_t buffer[1]; +} CORE_message_queue_Buffer; + +/** + * @brief Message Structure + * + * The following records define the organization of a message + * buffer. + */ +typedef struct { + /** This element allows this structure to be placed on chains. */ + Chain_Node Node; + #if defined(RTEMS_SCORE_COREMSG_ENABLE_MESSAGE_PRIORITY) + /** This field is the priority of this message. */ + int priority; + #endif + /** This field points to the contents of the message. */ + CORE_message_queue_Buffer Contents; +} CORE_message_queue_Buffer_control; + +/** + * @brief Message Queue Blocking Disciplines + * + * This enumerated types defines the possible blocking disciplines + * for a message queue. + */ +typedef enum { + /** This value indicates that blocking tasks are in FIFO order. */ + CORE_MESSAGE_QUEUE_DISCIPLINES_FIFO, + /** This value indicates that blocking tasks are in priority order. */ + CORE_MESSAGE_QUEUE_DISCIPLINES_PRIORITY +} CORE_message_queue_Disciplines; + +/** + * @brief Message Priority for Appending + * + * This is the priority constant used when appending messages onto + * a message queue. + */ +#define CORE_MESSAGE_QUEUE_SEND_REQUEST INT_MAX + +/** + * @brief Message Priority for Prepending + * + * This is the priority constant used when prepending messages onto + * a message queue. + */ +#define CORE_MESSAGE_QUEUE_URGENT_REQUEST INT_MIN + +/** + * @brief Message Insertion Operation Types + * + * 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 Core Message Queue Return Statuses + * + * This enumerated type defines the possible set of Core Message + * Queue handler return statuses. + */ +typedef enum { + /** This value indicates the operation completed sucessfully. */ + CORE_MESSAGE_QUEUE_STATUS_SUCCESSFUL, + /** This value indicates that the message was too large for this queue. */ + CORE_MESSAGE_QUEUE_STATUS_INVALID_SIZE, + /** This value indicates that there are too many messages pending. */ + CORE_MESSAGE_QUEUE_STATUS_TOO_MANY, + /** This value indicates that a receive was unsuccessful. */ + CORE_MESSAGE_QUEUE_STATUS_UNSATISFIED, + /** This value indicates that a blocking send was unsuccessful. */ + CORE_MESSAGE_QUEUE_STATUS_UNSATISFIED_NOWAIT, + /** This value indicates that the message queue being blocked upon + * was deleted while the thread was waiting. + */ + CORE_MESSAGE_QUEUE_STATUS_WAS_DELETED, + /** This value indicates that the thread had to timeout while waiting + * to receive a message because one did not become available. + */ + CORE_MESSAGE_QUEUE_STATUS_TIMEOUT, + /** This value indicates that a blocking receive was unsuccessful. */ + CORE_MESSAGE_QUEUE_STATUS_UNSATISFIED_WAIT +} CORE_message_queue_Status; + +/** + * @brief Core Message Queue Last Status + * + * This is the last status value. + */ +#define CORE_MESSAGE_QUEUE_STATUS_LAST CORE_MESSAGE_QUEUE_STATUS_UNSATISFIED_WAIT + +/** + * @brief Message Queue Attributes Type + * + * The following defines the control block used to manage the + * attributes of each message queue. + */ +typedef struct { + /** This field specifies the order in which blocking tasks will be ordered. */ + CORE_message_queue_Disciplines discipline; +} CORE_message_queue_Attributes; + +#if defined(RTEMS_SCORE_COREMSG_ENABLE_NOTIFICATION) + /** + * @brief Message Queue Notification Callback Prototype + * + * The following defines the type for a Notification handler. A + * notification handler is invoked when the message queue makes a + * 0->1 transition on pending messages. + */ + typedef void (*CORE_message_queue_Notify_Handler)( void * ); +#endif + +/** + * @brief Core Message Queue Control Structure + * + * The following defines the control block used to manage each + * Message Queue + */ +typedef struct { + /** This field is the Waiting Queue used to manage the set of tasks + * which are blocked waiting to receive a message from this queue. + */ + Thread_queue_Control Wait_queue; + /** This element is the set of attributes which define this instance's + * behavior. + */ + CORE_message_queue_Attributes Attributes; + /** This element is maximum number of messages which may be pending + * at any given time. + */ + uint32_t maximum_pending_messages; + /** This element is the number of messages which are currently pending. + */ + uint32_t number_of_pending_messages; + /** This is the size in bytes of the largest message which may be + * sent via this queue. + */ + size_t maximum_message_size; + /** This chain is the set of pending messages. It may be ordered by + * message priority or in FIFO order. + */ + Chain_Control Pending_messages; + /** This is the address of the memory allocated for message buffers. + * It is allocated are part of message queue initialization and freed + * as part of destroying it. + */ + CORE_message_queue_Buffer *message_buffers; + #if defined(RTEMS_SCORE_COREMSG_ENABLE_NOTIFICATION) + /** This is the routine invoked when the message queue transitions + * from zero (0) messages pending to one (1) message pending. + */ + CORE_message_queue_Notify_Handler notify_handler; + /** This field is the argument passed to the @ref notify_argument. */ + void *notify_argument; + #endif + /** This chain is the set of inactive messages. A message is inactive + * when it does not contain a pending message. + */ + Chain_Control Inactive_messages; +} CORE_message_queue_Control; + +/** + * @brief Initialize a Message Queue + * + * 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] the_message_queue_attributes points to the attributes that + * will be used with this message queue instance + * @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 + * + * @return 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_Attributes *the_message_queue_attributes, + uint32_t maximum_pending_messages, + size_t maximum_message_size +); + +/** + * @brief Close a Message Queue + * + * 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] remote_extract_callout is the routine to call for each thread + * that is extracted from the set of waiting threads + * @param[in] status is the status that each waiting thread will return + * from it's blocking service + */ +void _CORE_message_queue_Close( + CORE_message_queue_Control *the_message_queue, + Thread_queue_Flush_callout remote_extract_callout, + uint32_t status +); + +/** + * @brief Flush Pending Messages + * + * 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 + * + * @return This method returns the number of message pending messages flushed. + */ +uint32_t _CORE_message_queue_Flush( + CORE_message_queue_Control *the_message_queue +); + +/** + * @brief Flush Messages Support Routine + * + * This routine flushes all outstanding messages and returns + * them to the inactive message chain. + * + * @param[in] the_message_queue points to the message queue to flush + * + * @return This method returns the number of message pending messages flushed. + */ +uint32_t _CORE_message_queue_Flush_support( + CORE_message_queue_Control *the_message_queue +); + +#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. + * + * @param[in] the_message_queue points to the message queue to flush + */ + void _CORE_message_queue_Flush_waiting_threads( + CORE_message_queue_Control *the_message_queue + ); +#endif + +/** + * @brief Broadcast a Message to the Message Queue + * + * 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[in] id is the RTEMS object Id associated with this message queue. + * It is used when unblocking a remote thread. + * @param[in] api_message_queue_mp_support is the routine to invoke if + * a thread that is unblocked is actually a remote thread. + * @param[out] count points to the variable that will contain the + * number of tasks that are sent this message + * @return @a *count will contain the number of messages sent + * @return indication of the successful completion or reason for failure + */ +CORE_message_queue_Status _CORE_message_queue_Broadcast( + CORE_message_queue_Control *the_message_queue, + const void *buffer, + size_t size, + Objects_Id id, + CORE_message_queue_API_mp_support_callout api_message_queue_mp_support, + uint32_t *count +); + +/** + * @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] id is the RTEMS object Id associated with this message queue. + * It is used when unblocking a remote thread. + * @param[in] api_message_queue_mp_support is the routine to invoke if + * a thread that is unblocked is actually a remote thread. + * @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] timeout is the maximum number of clock ticks that the calling + * thread is willing to block if the message queue is full. + * @return indication of the successful completion or reason for failure + */ +CORE_message_queue_Status _CORE_message_queue_Submit( + CORE_message_queue_Control *the_message_queue, + const void *buffer, + size_t size, + Objects_Id id, + CORE_message_queue_API_mp_support_callout api_message_queue_mp_support, + CORE_message_queue_Submit_types submit_type, + bool wait, + Watchdog_Interval timeout +); + +/** + * @brief Size a Message from the Message Queue + * + * 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] id is the RTEMS object Id associated with this message queue. + * It is used when unblocking a remote thread. + * @param[in] buffer is the starting address of the message buffer to + * to be filled in with a message + * @param[in] size is 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] timeout is the maximum number of clock ticks that the calling + * thread is willing to block if the message queue is empty. + * + * @return indication of the successful completion or reason for failure + * @note Returns message priority via return are in TCB. + */ +void _CORE_message_queue_Seize( + CORE_message_queue_Control *the_message_queue, + Objects_Id id, + void *buffer, + size_t *size_p, + bool wait, + Watchdog_Interval timeout +); + +/** + * This kernel routine inserts the specified message into the + * message queue. It is assumed that the message has been filled + * in before this routine is called. + * + * @param[in] the_message_queue points to the message queue + * @param[in] the_message is the message to enqueue + * @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, + CORE_message_queue_Submit_types submit_type +); + +#ifndef __RTEMS_APPLICATION__ +#include <rtems/score/coremsg.inl> +#endif + +#ifdef __cplusplus +} +#endif + +/**@}*/ + +#endif +/* end of include file */ |