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 /* SPDX-License-Identifier: BSD-2-Clause */
 
 /**
  * @file
  *
  * @ingroup RTEMSScoreMessageQueue
  *
  * @brief This header file provides interfaces of the
  *   @ref RTEMSScoreMessageQueue which are used by the implementation and the
  *   @ref RTEMSImplApplConfig.
  */
 
 /*
  *  COPYRIGHT (c) 1989-2009.
  *  On-Line Applications Research Corporation (OAR).
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
 #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 This handler shall allocate the message buffer storage area for a
  *   message queue.
  *
  * The handler shall set the CORE_message_queue_Control::free_message_buffers
  * member.
  *
  * @param[out] the_message_queue is the message queue control.
  *
  * @param size is the message buffer storage area size to allocate.
  *
  * @param arg is the handler argument.
  *
  * @retval NULL The allocation failed.
  *
  * @return Otherwise the pointer to the allocated message buffer storage area
  *   begin shall be returned.
  */
 typedef void *( *CORE_message_queue_Allocate_buffers )(
   CORE_message_queue_Control *the_message_queue,
   size_t                      size,
   const void                 *arg
 );
 
 /**
  * @brief This handler allocates the message buffer storage area for a message
  *   queue from the RTEMS Workspace.
  *
  * The handler sets the CORE_message_queue_Control::free_message_buffers
  * to _Workspace_Free().
  *
  * @param[out] the_message_queue is the message queue control.
  *
  * @param size is the message buffer storage area size to allocate.
  *
  * @param arg is the unused handler argument.
  *
  * @retval NULL The allocation failed.
  *
  * @return Otherwise the pointer to the allocated message buffer storage area
  *   begin is returned.
  */
 void *_CORE_message_queue_Workspace_allocate(
   CORE_message_queue_Control *the_message_queue,
   size_t                      size,
   const void                 *arg
 );
 
 /**
  * @brief Initializes a message queue.
  *
  * @param[out] the_message_queue is the message queue to initialize.
  *
  * @param discipline is the blocking discipline for the message queue.
  *
  * @param maximum_pending_messages is the maximum number of messages that will
  *   be allowed to be pending at any given time.
  *
  * @param maximum_message_size is the size of the largest message that may be
  *   sent to this message queue instance.
  *
  * @param allocate_buffers is the message buffer storage area allocation
  *   handler.
  *
  * @param arg is the message buffer storage area allocation handler argument.
  *
  * @retval STATUS_SUCCESSFUL The message queue was initialized.
  *
  * @retval STATUS_MESSAGE_QUEUE_INVALID_SIZE Calculations with the maximum
  *   pending messages or maximum message size produced an integer overflow.
  *
  * @retval STATUS_MESSAGE_QUEUE_NO_MEMORY The message buffer storage area
  *   allocation failed.
  */
 Status_Control _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,
   CORE_message_queue_Allocate_buffers  allocate_buffers,
   const void                          *arg
 );
 
 /**
  * @brief 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 @a the_message_queue's task wait queue.
  *
  * @param[in, out] the_message_queue The message queue to close.
  * @param[in, out] 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 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 @a the_message_queue's pending message queue.  The
  * number of messages flushed from the queue is returned.
  *
  * @param[in, out] the_message_queue The message queue to flush.
  * @param queue_context The thread queue context with interrupts disabled.
  *
  * @return 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 Flushes 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, out] the_message_queue The message queue to flush.
  *
  * @return This method returns the number of messages flushed from the queue.
  */
   void _CORE_message_queue_Flush_waiting_threads(
     CORE_message_queue_Control *the_message_queue
   );
 #endif
 
 /**
  * @brief 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.
  *
  * @param[in, out] the_message_queue The message queue to operate upon.
  * @param buffer The starting address of the message to broadcast.
  * @param size The size of the message being broadcast.
  * @param[out] count The variable that will contain the
  *        number of tasks that are sent this message.
  * @param queue_context The thread queue context used for
  *   _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().
  *
  * @retval STATUS_SUCCESSFUL The message was successfully broadcast.
  * @retval STATUS_MESSAGE_INVALID_SIZE The message size was too big.
  */
 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 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.
  *
  * @param[in, out] the_message_queue The message queue to operate upon.
  * @param executing The executing thread.
  * @param buffer The starting address of the message to send.
  * @param size The size of the message being send.
  * @param submit_type Determines whether the message is prepended,
  *        appended, or enqueued in priority order.
  * @param wait Indicates whether the calling thread is willing to block
  *        if the message queue is full.
  * @param queue_context The thread queue context used for
  *   _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().
  *
  * @retval STATUS_SUCCESSFUL The message was successfully submitted to the message queue.
  * @retval STATUS_MESSAGE_INVALID_SIZE The message size was too big.
  * @retval STATUS_TOO_MANY No message buffers were available.
  * @retval STATUS_MESSAGE_QUEUE_WAIT_IN_ISR The caller is in an ISR, do not block!
  * @retval STATUS_TIMEOUT A timeout occurred.
  */
 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 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.
  *
  * @param[in, out] the_message_queue The message queue to seize a message from.
  * @param executing The executing thread.
  * @param[out] buffer The starting address of the message buffer to
  *        to be filled in with a message.
  * @param[out] size_p The size of the @a buffer,
  *        indicates the maximum size message that the caller can receive.
  * @param wait Indicates whether the calling thread is willing to block
  *        if the message queue is empty.
  * @param queue_context The thread queue context used for
  *   _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().
  *
  * @retval STATUS_SUCCESSFUL The message was successfully seized from the message queue.
  * @retval STATUS_UNSATISFIED Wait was set to false and there is currently no pending message.
  * @retval STATUS_TIMEOUT A timeout occurred.
  *
  * @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 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.
  *
  * @param[in, out] the_message_queue The message queue to insert a message in.
  * @param[in, out] the_message The message to insert in the message queue.
  * @param content_source The message content source.
  * @param content_size The message content size in bytes.
  * @param 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         *the_message,
   const void                        *content_source,
   size_t                             content_size,
   CORE_message_queue_Submit_types    submit_type
 );
 
 /**
  * @brief Sends a message to the message queue.
  *
  * @param[in, out] the_message_queue The message queue to send a message to.
  * @param buffer The starting address of the message to send.
  * @param sizeis The size of the message being send.
  * @param wait Indicates whether the calling thread is willing to block
  *        if the message queue is full.
  * @param queue_context The thread queue context used for
  *   _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().
  *
  * @retval STATUS_SUCCESSFUL The message was successfully submitted to the message queue.
  * @retval STATUS_MESSAGE_INVALID_SIZE The message size was too big.
  * @retval STATUS_TOO_MANY No message buffers were available.
  * @retval STATUS_MESSAGE_QUEUE_WAIT_IN_ISR The caller is in an ISR, do not block!
  * @retval STATUS_TIMEOUT A timeout occurred.
  */
 static inline 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
   );
 }
 
 /**
  * @brief Sends an urgent message to the message queue.
  *
  * @param[in, out] the_message_queue The message queue to send an urgent message to.
  * @param buffer The starting address of the message to send.
  * @param sizeis The size of the message being send.
  * @param wait Indicates whether the calling thread is willing to block
  *        if the message queue is full.
  * @param queue_context The thread queue context used for
  *   _CORE_message_queue_Acquire() or _CORE_message_queue_Acquire_critical().
  *
  * @retval STATUS_SUCCESSFUL The message was successfully submitted to the message queue.
  * @retval STATUS_MESSAGE_INVALID_SIZE The message size was too big.
  * @retval STATUS_TOO_MANY No message buffers were available.
  * @retval STATUS_MESSAGE_QUEUE_WAIT_IN_ISR The caller is in an ISR, do not block!
  * @retval STATUS_TIMEOUT A timeout occurred.
  */
 static inline 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
   );
 }
 
 /**
  * @brief Acquires the message queue.
  *
  * @param[in, out] the_message_queue The message queue to acquire.
  * @param queue_context The thread queue context.
  */
 static inline 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 );
 }
 
 /**
  * @brief Acquires the message queue critical.
  *
  * @param[in, out] the_message_queue The message queue to acquire critical.
  * @param queue_context The thread queue context.
  */
 static inline 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 );
 }
 
 /**
  * @brief Releases the message queue.
  *
  * @param[in, out] the_message_queue The message queue to release.
  * @param queue_context The thread queue context.
  */
 static inline 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 );
 }
 
 /**
  * @brief 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.
  *
  * @param source The source message buffer to be copied.
  * @param[out] destination The destination messag buffer to copy the source to.
  * @param size The size of the source buffer.
  */
 static inline void _CORE_message_queue_Copy_buffer (
   const void *source,
   void       *destination,
   size_t      size
 )
 {
   memcpy(destination, source, size);
 }
 
 /**
  * @brief Allocates a message buffer from the inactive message buffer chain.
  *
  * This function allocates a message buffer from the inactive
  * message buffer chain.
  *
  * @param the_message_queue The message queue to operate upon.
  *
  * @retval pointer The allocated message buffer.
  * @retval NULL The inactive message buffer chain is empty.
  */
 static inline CORE_message_queue_Buffer *
 _CORE_message_queue_Allocate_message_buffer (
     CORE_message_queue_Control *the_message_queue
 )
 {
    return (CORE_message_queue_Buffer *)
      _Chain_Get_unprotected( &the_message_queue->Inactive_messages );
 }
 
 /**
  * @brief Frees a message buffer to inactive message buffer chain.
  *
  * This routine frees a message buffer to the inactive
  * message buffer chain.
  *
  * @param[in, out] the_message_queue The message queue to free the message buffer to.
  * @param[out] the_message The message to be freed.
  */
 static inline void _CORE_message_queue_Free_message_buffer (
   CORE_message_queue_Control *the_message_queue,
   CORE_message_queue_Buffer  *the_message
 )
 {
   _Chain_Append_unprotected( &the_message_queue->Inactive_messages, &the_message->Node );
 }
 
 /**
  * @brief Gets message priority.
  *
  * This function returns the priority of @a the_message.
  *
  * @param the_message The message to obtain the priority from.
  *
  * @retval priority The priority of this message.
  * @retval 0 Message priority is disabled.
  *
  * @note It encapsulates the optional behavior that message priority is
  *       disabled if no API requires it.
  */
 static inline int _CORE_message_queue_Get_message_priority (
   const CORE_message_queue_Buffer *the_message
 )
 {
   #if defined(RTEMS_SCORE_COREMSG_ENABLE_MESSAGE_PRIORITY)
     return the_message->priority;
   #else
     return 0;
   #endif
 }
 
 /**
  * @brief 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.
  *
  * @param[in, out] the_message_queue The message queue to get the first message from.
  *
  * @retval pointer The first message if the message queue is not empty.
  * @retval NULL The message queue is empty.
  */
 static inline
   CORE_message_queue_Buffer *_CORE_message_queue_Get_pending_message (
   CORE_message_queue_Control *the_message_queue
 )
 {
   return (CORE_message_queue_Buffer *)
     _Chain_Get_unprotected( &the_message_queue->Pending_messages );
 }
 
 #if defined(RTEMS_SCORE_COREMSG_ENABLE_NOTIFICATION)
   /**
    * @brief Checks if notification is enabled.
    *
    * This function returns true if notification is enabled on this message
    * queue and false otherwise.
    *
    * @param the_message_queue The message queue to check if the notification is enabled.
    *
    * @retval true Notification is enabled on this message queue.
    * @retval false Notification is not enabled on this message queue.
    */
   static inline bool _CORE_message_queue_Is_notify_enabled (
     CORE_message_queue_Control *the_message_queue
   )
   {
     return (the_message_queue->notify_handler != NULL);
   }
 #endif
 
 /**
  * @brief Initializes notification information.
  *
  * This routine initializes the notification information for
  * @a the_message_queue.
  *
  * @param[out] the_message_queue The message queue to initialize the notification information.
  * @param[out] the_handler The notification information for the message queue.
  */
 #if defined(RTEMS_SCORE_COREMSG_ENABLE_NOTIFICATION)
   static inline 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
 
 /**
  * @brief 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.
  *
  * @param[in, out] the_message_queue The message queue to operate upon.
  * @param buffer The buffer that is copied to the threads mutable_object.
  * @param size The size of the buffer.
  * @param submit_type Indicates whether the thread should be willing to block in the future.
  * @param queue_context The thread queue context.
  *
  * @retval thread The Thread_Control for the first locked thread, if there is a locked thread.
  * @retval NULL There are pending messages or no thread waiting to receive.
  */
 static inline 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_queue_Heads *heads;
   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.
    */
   heads = the_message_queue->Wait_queue.Queue.heads;
   if ( heads == NULL ) {
     return NULL;
   }
 
   the_thread = ( *the_message_queue->operations->surrender )(
     &the_message_queue->Wait_queue.Queue,
     heads,
     NULL,
     queue_context
   );
 
    *(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_Resume(
     &the_message_queue->Wait_queue.Queue,
     the_thread,
     queue_context
   );
 
   return the_thread;
 }
 
 /** @} */
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif
 /* end of include file */

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