quc.c

test file nucleus source

/*      created queues.  All tasks suspended on the queue are            */
/*      resumed.  Note that this function does not free the memory       */
/*      associated with the queue.                                       */
/*                                                                       */
/* CALLED BY                                                             */
/*                                                                       */
/*      Application                                                      */
/*      QUCE_Delete_Queue                   Error checking shell         */
/*                                                                       */
/* CALLS                                                                 */
/*                                                                       */
/*      CSC_Remove_From_List                Remove node from list        */
/*      [HIC_Make_History_Entry]            Make entry in history log    */
/*      TCC_Resume_Task                     Resume a suspended task      */
/*      [TCT_Check_Stack]                   Stack checking function      */
/*      TCT_Control_To_System               Transfer control to system   */
/*      TCT_Protect                         Protect created list         */
/*      TCT_Set_Current_Protect             Setup current protect pointer*/
/*      TCT_System_Protect                  Protect against system access*/
/*      TCT_System_Unprotect                Release system protection    */
/*      TCT_Unprotect                       Release protection           */
/*                                                                       */
/* INPUTS                                                                */
/*                                                                       */
/*      queue_ptr                           Queue control block pointer  */
/*                                                                       */
/* OUTPUTS                                                               */
/*                                                                       */
/*      NU_SUCCESS                                                       */
/*                                                                       */
/* HISTORY                                                               */
/*                                                                       */
/*        DATE                    REMARKS                                */
/*                                                                       */
/*      03-01-1993      Created initial version 1.0                      */
/*      04-19-1993      Verified version 1.0                             */
/*      03-01-1994      Changed function interfaces to                   */
/*                      match those in prototype,                        */
/*                      added register options, changed                  */
/*                      protection logic to reduce                       */
/*                      overhead, resulting in                           */
/*                      version 1.1                                      */
/*                                                                       */
/*      03-18-1994      Verified version 1.1                             */
/*                                                                       */
/*************************************************************************/
STATUS  QUC_Delete_Queue(NU_QUEUE *queue_ptr)
{

R1 QU_QCB      *queue;                      /* Queue control block ptr   */
QU_SUSPEND     *suspend_ptr;                /* Suspend block pointer     */
QU_SUSPEND     *next_ptr;                   /* Next suspend block pointer*/
STATUS          preempt;                    /* Status for resume call    */
NU_SUPERV_USER_VARIABLES

    /* Move input queue pointer into internal pointer.  */
    queue =  (QU_QCB *) queue_ptr;

    /* Switch to supervisor mode */
    NU_SUPERVISOR_MODE();

#ifdef  NU_ENABLE_STACK_CHECK

    /* Call stack checking function to check for an overflow condition.  */
    TCT_Check_Stack();

#endif

#ifdef  NU_ENABLE_HISTORY

    /* Make an entry that corresponds to this function in the system history
       log.  */
    HIC_Make_History_Entry(NU_DELETE_QUEUE_ID, (UNSIGNED) queue,
                                        (UNSIGNED) 0, (UNSIGNED) 0);

#endif

    /* Protect against access to the queue.  */
    TCT_System_Protect();

#ifdef INCLUDE_PROVIEW
    _RTProf_DumpQueue(RT_PROF_DELETE_QUEUE,queue,RT_PROF_OK);
#endif

    /* Clear the queue ID.  */
    queue -> qu_id =  0;

    /* Release protection.  */
    TCT_Unprotect();

    /* Protect against access to the list of created queues.  */
    TCT_Protect(&QUD_List_Protect);

    /* Remove the queue from the list of created queues.  */
    CSC_Remove_From_List(&QUD_Created_Queues_List, &(queue -> qu_created));

    /* Decrement the total number of created queues.  */
    QUD_Total_Queues--;

    /* Pickup the suspended task pointer list.  */
    suspend_ptr =  queue -> qu_suspension_list;

    /* Walk the chain task(s) currently suspended on the queue.  */
    preempt =  0;
    while (suspend_ptr)
    {

        /* Protect against system access.  */
        TCT_System_Protect();

        /* Resume the suspended task.  Insure that the status returned is
           NU_QUEUE_DELETED.  */
        suspend_ptr -> qu_return_status =  NU_QUEUE_DELETED;

        /* Point to the next suspend structure in the link.  */
        next_ptr =  (QU_SUSPEND *) (suspend_ptr -> qu_suspend_link.cs_next);

        /* Resume the specified task.  */
        preempt =  preempt |
            TCC_Resume_Task((NU_TASK *) suspend_ptr -> qu_suspended_task,
                                                NU_QUEUE_SUSPEND);

        /* Determine if the next is the same as the head pointer.  */
        if (next_ptr == queue -> qu_suspension_list)

            /* Clear the suspension pointer to signal the end of the list
               traversal.  */
            suspend_ptr =  NU_NULL;
        else

            /* Position suspend pointer to the next pointer.  */
            suspend_ptr =  next_ptr;

        /* Modify current protection.  */
        TCT_Set_Current_Protect(&QUD_List_Protect);

        /* Clear the system protection.  */
        TCT_System_Unprotect();
    }

    /* Pickup the urgent message suspension list.  */
    suspend_ptr =  queue -> qu_urgent_list;

    /* Walk the chain task(s) currently suspended on the queue.  */
    while (suspend_ptr)
    {

        /* Protect against system access.  */
        TCT_System_Protect();

        /* Resume the suspended task.  Insure that the status returned is
           NU_QUEUE_DELETED.  */
        suspend_ptr -> qu_return_status =  NU_QUEUE_DELETED;

        /* Point to the next suspend structure in the link.  */
        next_ptr =  (QU_SUSPEND *) (suspend_ptr -> qu_suspend_link.cs_next);

        /* Resume the specified task.  */
        preempt =  preempt |
                TCC_Resume_Task((NU_TASK *) suspend_ptr -> qu_suspended_task,
                                                NU_QUEUE_SUSPEND);

        /* Determine if the next is the same as the head pointer.  */
        if (next_ptr == queue -> qu_urgent_list)

            /* Clear the suspension pointer to signal the end of the list
               traversal.  */
            suspend_ptr =  NU_NULL;
        else

            /* Position to the next suspend block in the list.  */
            suspend_ptr =  next_ptr;

        /* Modify current protection.  */
        TCT_Set_Current_Protect(&QUD_List_Protect);

        /* Clear the system protection.  */
        TCT_System_Unprotect();
    }

    /* Determine if preemption needs to occur.  */
    if (preempt)

        /* Transfer control to system to facilitate preemption.  */
        TCT_Control_To_System();

    /* Release protection against access to the list of created queues.  */
    TCT_Unprotect();

    /* Return to user mode */
    NU_USER_MODE();

    /* Return a successful completion.  */
    return(NU_SUCCESS);
}


/*************************************************************************/
/*                                                                       */
/* FUNCTION                                                              */
/*                                                                       */
/*      QUC_Send_To_Queue                                                */
/*                                                                       */
/* DESCRIPTION                                                           */
/*                                                                       */
/*      This function sends a message to the specified queue.  The       */
/*      message length is determined by the caller.  If there are one    */
/*      or more tasks suspended on the queue for a message, the message  */
/*      is copied into the message area of the first waiting task.  If   */
/*      the task's request is satisfied, it is resumed.  Otherwise, if   */
/*      the queue cannot hold the message, suspension of the calling     */
/*      task is an option of the caller.                                 */
/*                                                                       */
/* CALLED BY                                                             */
/*                                                                       */
/*      Application                                                      */
/*      QUCE_Send_To_Queue                  Error checking shell         */
/*                                                                       */
/* CALLS                                                                 */
/*                                                                       */
/*      CSC_Place_On_List                   Place on suspend list        */
/*      CSC_Priority_Place_On_List          Place on priority list       */
/*      CSC_Remove_From_List                Remove from suspend list     */
/*      [HIC_Make_History_Entry]            Make entry in history log    */
/*      TCC_Resume_Task                     Resume a suspended task      */
/*      TCC_Suspend_Task                    Suspend calling task         */
/*      TCC_Task_Priority                   Pickup task's priority       */
/*      [TCT_Check_Stack]                   Stack checking function      */
/*      TCT_Control_To_System               Transfer control to system   */
/*      TCT_Current_Thread                  Pickup current thread pointer*/
/*      TCT_System_Protect                  Protect queue                */
/*      TCT_Unprotect                       Release protection           */
/*                                                                       */
/* INPUTS                                                                */
/*                                                                       */
/*      queue_ptr                           Queue control block pointer  */
/*      message                             Pointer to message to send   */
/*      size                                Size of message to send      */
/*      suspend                             Suspension option if full    */
/*                                                                       */
/* OUTPUTS                                                               */
/*                                                                       */
/*      NU_SUCCESS                          If service is successful     */
/*      NU_QUEUE_FULL                       If queue is currently full   */
/*      NU_TIMEOUT                          If timeout on service expires*/
/*      NU_QUEUE_DELETED                    If queue was deleted during  */
/*                                            suspension                 */
/*      NU_QUEUE_RESET                      If queue was reset during    */
/*                                            suspension                 */
/*                                                                       */
/* HISTORY                                                               */
/*                                                                       */
/*        DATE                    REMARKS                                */
/*                                                                       */
/*      03-01-1993      Created initial version 1.0                      */
/*      04-19-1993      Verified version 1.0                             */
/*      03-01-1994      Changed function interfaces to                   */
/*                      match those in prototype,                        */
/*                      added register options, changed                  */
/*                      protection logic to reduce                       */
/*                      overhead, optimized copy loop,                   */
/*                      resulting in version 1.1                         */
/*                                                                       */
/*      03-18-1994      Verified version 1.1                             */
/*                                                                       */
/*************************************************************************/
STATUS  QUC_Send_To_Queue(NU_QUEUE *queue_ptr, VOID *message, UNSIGNED size,
                                                        UNSIGNED suspend)
{

R1 QU_QCB      *queue;                      /* Queue control block ptr   */
QU_SUSPEND      suspend_block;              /* Allocate suspension block */
QU_SUSPEND     *suspend_ptr;                /* Pointer to suspend block  */
R3 UNSIGNED_PTR source;                     /* Pointer to source         */
R4 UNSIGNED_PTR destination;                /* Pointer to destination    */
UNSIGNED        copy_size;                  /* Partial copy size         */
R2 INT          i;                          /* Working counter           */
TC_TCB         *task;                       /* Task pointer              */
STATUS          preempt;                    /* Preempt flag              */
STATUS          status;                     /* Completion status         */
NU_SUPERV_USER_VARIABLES

    /* Switch to supervisor mode */
    NU_SUPERVISOR_MODE();

    /* Move input queue pointer into internal pointer.  */
    queue =  (QU_QCB *) queue_ptr;


#ifdef  NU_ENABLE_STACK_CHECK