os_q.c

ucosii嵌入式操作系统源代码

    }
    pq = (OS_Q *)pevent->OSEventPtr;                  /* Point to queue control block                  */
    if (pq->OSQEntries >= pq->OSQSize) {              /* Make sure queue is not full                   */
        OS_EXIT_CRITICAL();
        return (OS_Q_FULL);
    }
    if (pq->OSQOut == pq->OSQStart) {                 /* Wrap OUT ptr if we are at the 1st queue entry */
        pq->OSQOut = pq->OSQEnd;
    }
    pq->OSQOut--;
    *pq->OSQOut = msg;                                /* Insert message into queue                     */
    pq->OSQEntries++;                                 /* Update the nbr of entries in the queue        */
    OS_EXIT_CRITICAL();
    return (OS_NO_ERR);
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
*                                        POST MESSAGE TO A QUEUE
*
* Description: This function sends a message to a queue.  This call has been added to reduce code size
*              since it can replace both OSQPost() and OSQPostFront().  Also, this function adds the
*              capability to broadcast a message to ALL tasks waiting on the message queue.
*
* Arguments  : pevent        is a pointer to the event control block associated with the desired queue
*
*              msg           is a pointer to the message to send.  You MUST NOT send a NULL pointer.
*
*              opt           determines the type of POST performed:
*                            OS_POST_OPT_NONE         POST to a single waiting task
*                                                     (Identical to OSQPost())
*                            OS_POST_OPT_BROADCAST    POST to ALL tasks that are waiting on the queue
*                            OS_POST_OPT_FRONT        POST as LIFO (Simulates OSQPostFront())
*
*                            Below is a list of ALL the possible combination of these flags:
*
*                                 1) OS_POST_OPT_NONE
*                                    identical to OSQPost()
*
*                                 2) OS_POST_OPT_FRONT
*                                    identical to OSQPostFront()
*
*                                 3) OS_POST_OPT_BROADCAST
*                                    identical to OSQPost() but will broadcast 'msg' to ALL waiting tasks
*
*                                 4) OS_POST_OPT_FRONT + OS_POST_OPT_BROADCAST  is identical to
*                                    OSQPostFront() except that will broadcast 'msg' to ALL waiting tasks
*
* Returns    : OS_NO_ERR             The call was successful and the message was sent
*              OS_Q_FULL             If the queue cannot accept any more messages because it is full.
*              OS_ERR_EVENT_TYPE     If you didn't pass a pointer to a queue.
*              OS_ERR_PEVENT_NULL    If 'pevent' is a NULL pointer
*              OS_ERR_POST_NULL_PTR  If you are attempting to post a NULL pointer
*
* Warning    : Interrupts can be disabled for a long time if you do a 'broadcast'.  In fact, the
*              interrupt disable time is proportional to the number of tasks waiting on the queue.
*********************************************************************************************************
*/

#if OS_Q_POST_OPT_EN > 0
INT8U  OSQPostOpt (OS_EVENT *pevent, void *msg, INT8U opt)
{
#if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */
    OS_CPU_SR  cpu_sr;
#endif
    OS_Q      *pq;


#if OS_ARG_CHK_EN > 0
    if (pevent == (OS_EVENT *)0) {                    /* Validate 'pevent'                             */
        return (OS_ERR_PEVENT_NULL);
    }
    if (msg == (void *)0) {                           /* Make sure we are not posting a NULL pointer   */
        return (OS_ERR_POST_NULL_PTR);
    }
    if (pevent->OSEventType != OS_EVENT_TYPE_Q) {     /* Validate event block type                     */
        return (OS_ERR_EVENT_TYPE);
    }
#endif
    OS_ENTER_CRITICAL();
    if (pevent->OSEventGrp != 0x00) {                 /* See if any task pending on queue              */
        if ((opt & OS_POST_OPT_BROADCAST) != 0x00) {  /* Do we need to post msg to ALL waiting tasks ? */
            while (pevent->OSEventGrp != 0x00) {      /* Yes, Post to ALL tasks waiting on queue       */
                OS_EventTaskRdy(pevent, msg, OS_STAT_Q);
            }
        } else {
            OS_EventTaskRdy(pevent, msg, OS_STAT_Q);  /* No,  Post to HPT waiting on queue             */
        }
        OS_EXIT_CRITICAL();
        OS_Sched();                                   /* Find highest priority task ready to run       */
        return (OS_NO_ERR);
    }
    pq = (OS_Q *)pevent->OSEventPtr;                  /* Point to queue control block                  */
    if (pq->OSQEntries >= pq->OSQSize) {              /* Make sure queue is not full                   */
        OS_EXIT_CRITICAL();
        return (OS_Q_FULL);
    }
    if ((opt & OS_POST_OPT_FRONT) != 0x00) {          /* Do we post to the FRONT of the queue?         */
        if (pq->OSQOut == pq->OSQStart) {             /* Yes, Post as LIFO, Wrap OUT pointer if we ... */
            pq->OSQOut = pq->OSQEnd;                  /*      ... are at the 1st queue entry           */
        }
        pq->OSQOut--;
        *pq->OSQOut = msg;                            /*      Insert message into queue                */
    } else {                                          /* No,  Post as FIFO                             */
        *pq->OSQIn++ = msg;                           /*      Insert message into queue                */
        if (pq->OSQIn == pq->OSQEnd) {                /*      Wrap IN ptr if we are at end of queue    */
            pq->OSQIn = pq->OSQStart;
        }
    }
    pq->OSQEntries++;                                 /* Update the nbr of entries in the queue        */
    OS_EXIT_CRITICAL();
    return (OS_NO_ERR);
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
*                                        QUERY A MESSAGE QUEUE
*
* Description: This function obtains information about a message queue.
*
* Arguments  : pevent        is a pointer to the event control block associated with the desired queue
*
*              pdata         is a pointer to a structure that will contain information about the message
*                            queue.
*
* Returns    : OS_NO_ERR           The call was successful and the message was sent
*              OS_ERR_EVENT_TYPE   If you are attempting to obtain data from a non queue.
*              OS_ERR_PEVENT_NULL  If 'pevent' is a NULL pointer
*********************************************************************************************************
*/

#if OS_Q_QUERY_EN > 0
INT8U  OSQQuery (OS_EVENT *pevent, OS_Q_DATA *pdata)
{
#if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */
    OS_CPU_SR  cpu_sr;
#endif
    OS_Q      *pq;
    INT8U     *psrc;
    INT8U     *pdest;


#if OS_ARG_CHK_EN > 0
    if (pevent == (OS_EVENT *)0) {                         /* Validate 'pevent'                        */
        return (OS_ERR_PEVENT_NULL);
    }
    if (pevent->OSEventType != OS_EVENT_TYPE_Q) {          /* Validate event block type                */
        return (OS_ERR_EVENT_TYPE);
    }
#endif
    OS_ENTER_CRITICAL();
    pdata->OSEventGrp = pevent->OSEventGrp;                /* Copy message queue wait list           */
    psrc              = &pevent->OSEventTbl[0];
    pdest             = &pdata->OSEventTbl[0];
#if OS_EVENT_TBL_SIZE > 0
    *pdest++          = *psrc++;
#endif

#if OS_EVENT_TBL_SIZE > 1
    *pdest++          = *psrc++;
#endif

#if OS_EVENT_TBL_SIZE > 2
    *pdest++          = *psrc++;
#endif

#if OS_EVENT_TBL_SIZE > 3
    *pdest++          = *psrc++;
#endif

#if OS_EVENT_TBL_SIZE > 4
    *pdest++          = *psrc++;
#endif

#if OS_EVENT_TBL_SIZE > 5
    *pdest++          = *psrc++;
#endif

#if OS_EVENT_TBL_SIZE > 6
    *pdest++          = *psrc++;
#endif

#if OS_EVENT_TBL_SIZE > 7
    *pdest            = *psrc;
#endif
    pq = (OS_Q *)pevent->OSEventPtr;
    if (pq->OSQEntries > 0) {
        pdata->OSMsg = *pq->OSQOut;                        /* Get next message to return if available  */
    } else {
        pdata->OSMsg = (void *)0;
    }
    pdata->OSNMsgs = pq->OSQEntries;
    pdata->OSQSize = pq->OSQSize;
    OS_EXIT_CRITICAL();
    return (OS_NO_ERR);
}
#endif                                                     /* OS_Q_QUERY_EN                            */

/*$PAGE*/
/*
*********************************************************************************************************
*                                      QUEUE MODULE INITIALIZATION
*
* Description : This function is called by uC/OS-II to initialize the message queue module.  Your
*               application MUST NOT call this function.
*
* Arguments   :  none
*
* Returns     : none
*
* Note(s)    : This function is INTERNAL to uC/OS-II and your application should not call it.
*********************************************************************************************************
*/

void  OS_QInit (void)
{
#if OS_MAX_QS == 1
    OSQFreeList         = &OSQTbl[0];            /* Only ONE queue!                                    */
    OSQFreeList->OSQPtr = (OS_Q *)0;
#endif

#if OS_MAX_QS >= 2
    INT16U  i;
    OS_Q   *pq1;
    OS_Q   *pq2;


    pq1 = &OSQTbl[0];
    pq2 = &OSQTbl[1];
    for (i = 0; i < (OS_MAX_QS - 1); i++) {      /* Init. list of free QUEUE control blocks            */
        pq1->OSQPtr = pq2;
        pq1++;
        pq2++;
    }
    pq1->OSQPtr = (OS_Q *)0;
    OSQFreeList = &OSQTbl[0];
#endif
}
#endif                                                     /* OS_Q_EN                                  */