OS_EXIT_CRITICAL();             *err = OS_ERR_INVALID_OPT;             return (pevent);    }}#endif/*$PAGE*//***********************************************************************************************************                                           FLUSH QUEUE** Description : This function is used to flush the contents of the message queue.** Arguments   : none** Returns     : OS_NO_ERR           upon success*               OS_ERR_EVENT_TYPE   If you didn't pass a pointer to a queue*               OS_ERR_PEVENT_NULL  If 'pevent' is a NULL pointer**********************************************************************************************************/#if OS_Q_FLUSH_EN > 0INT8U  OSQFlush (OS_EVENT *pevent){#if OS_CRITICAL_METHOD == 3                           /* Allocate storage for CPU status register      */    OS_CPU_SR  cpu_sr;#endif        OS_Q      *pq;#if OS_ARG_CHK_EN > 0    if (pevent == (OS_EVENT *)0) {                    /* Validate 'pevent'                             */        return (OS_ERR_PEVENT_NULL);    }    if (pevent->OSEventType != OS_EVENT_TYPE_Q) {     /* Validate event block type                     */        return (OS_ERR_EVENT_TYPE);    }#endif    OS_ENTER_CRITICAL();    pq             = (OS_Q *)pevent->OSEventPtr;      /* Point to queue storage structure              */    pq->OSQIn      = pq->OSQStart;    pq->OSQOut     = pq->OSQStart;    pq->OSQEntries = 0;    OS_EXIT_CRITICAL();    return (OS_NO_ERR);}#endif/*$PAGE*//***********************************************************************************************************                                     PEND ON A QUEUE FOR A MESSAGE** Description: This function waits for a message to be sent to a queue** Arguments  : pevent        is a pointer to the event control block associated with the desired queue**              timeout       is an optional timeout period (in clock ticks).  If non-zero, your task will*                            wait for a message to arrive at the queue up to the amount of time*                            specified by this argument.  If you specify 0, however, your task will wait*                            forever at the specified queue or, until a message arrives.**              err           is a pointer to where an error message will be deposited.  Possible error*                            messages are:**                            OS_NO_ERR           The call was successful and your task received a*                                                message.*                            OS_TIMEOUT          A message was not received within the specified timeout*                            OS_ERR_EVENT_TYPE   You didn't pass a pointer to a queue*                            OS_ERR_PEVENT_NULL  If 'pevent' is a NULL pointer*                            OS_ERR_PEND_ISR     If you called this function from an ISR and the result*                                                would lead to a suspension.** Returns    : != (void *)0  is a pointer to the message received*              == (void *)0  if no message was received or,*                            if 'pevent' is a NULL pointer or,*                            if you didn't pass a pointer to a queue.**********************************************************************************************************/void  *OSQPend (OS_EVENT *pevent, INT16U timeout, INT8U *err){#if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */    OS_CPU_SR  cpu_sr;#endif        void      *msg;    OS_Q      *pq;    if (OSIntNesting > 0) {                      /* See if called from ISR ...                         */        *err = OS_ERR_PEND_ISR;                  /* ... can't PEND from an ISR                         */        return ((void *)0);    }#if OS_ARG_CHK_EN > 0    if (pevent == (OS_EVENT *)0) {               /* Validate 'pevent'                                  */        *err = OS_ERR_PEVENT_NULL;        return ((void *)0);    }    if (pevent->OSEventType != OS_EVENT_TYPE_Q) {/* Validate event block type                          */        *err = OS_ERR_EVENT_TYPE;        return ((void *)0);    }#endif    OS_ENTER_CRITICAL();    pq = (OS_Q *)pevent->OSEventPtr;             /* Point at queue control block                       */    if (pq->OSQEntries != 0) {                   /* See if any messages in the queue                   */        msg = *pq->OSQOut++;                     /* Yes, extract oldest message from the queue         */        pq->OSQEntries--;                        /* Update the number of entries in the queue          */        if (pq->OSQOut == pq->OSQEnd) {          /* Wrap OUT pointer if we are at the end of the queue */            pq->OSQOut = pq->OSQStart;        }        OS_EXIT_CRITICAL();        *err = OS_NO_ERR;        return (msg);                            /* Return message received                            */    }    OSTCBCur->OSTCBStat |= OS_STAT_Q;            /* Task will have to pend for a message to be posted  */    OSTCBCur->OSTCBDly   = timeout;              /* Load timeout into TCB                              */    OS_EventTaskWait(pevent);                    /* Suspend task until event or timeout occurs         */    OS_EXIT_CRITICAL();    OS_Sched();                                  /* Find next highest priority task ready to run       */    OS_ENTER_CRITICAL();    msg = OSTCBCur->OSTCBMsg;    if (msg != (void *)0) {                      /* Did we get a message?                              */        OSTCBCur->OSTCBMsg      = (void *)0;     /* Extract message from TCB (Put there by QPost)      */        OSTCBCur->OSTCBStat     = OS_STAT_RDY;        OSTCBCur->OSTCBEventPtr = (OS_EVENT *)0; /* No longer waiting for event                        */        OS_EXIT_CRITICAL();        *err                    = OS_NO_ERR;        return (msg);                            /* Return message received                            */    }    OS_EventTO(pevent);                          /* Timed out                                          */    OS_EXIT_CRITICAL();    *err = OS_TIMEOUT;                           /* Indicate a timeout occured                         */    return ((void *)0);                          /* No message received                                */}/*$PAGE*//***********************************************************************************************************                                        POST MESSAGE TO A QUEUE** Description: This function sends a message to a 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.** 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**********************************************************************************************************/#if OS_Q_POST_EN > 0INT8U  OSQPost (OS_EVENT *pevent, void *msg){#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              */        OS_EventTaskRdy(pevent, msg, OS_STAT_Q);      /* Ready highest priority task waiting on event  */        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);    }    *pq->OSQIn++ = msg;                               /* Insert message into queue                     */    pq->OSQEntries++;                                 /* Update the nbr of entries in the queue        */    if (pq->OSQIn == pq->OSQEnd) {                    /* Wrap IN ptr if we are at end of queue         */        pq->OSQIn = pq->OSQStart;    }    OS_EXIT_CRITICAL();    return (OS_NO_ERR);}#endif/*$PAGE*//***********************************************************************************************************                                   POST MESSAGE TO THE FRONT OF A QUEUE** Description: This function sends a message to a queue but unlike OSQPost(), the message is posted at*              the front instead of the end of the queue.  Using OSQPostFront() allows you to send*              'priority' messages.** 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.** 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 to a non queue.**********************************************************************************************************/#if OS_Q_POST_FRONT_EN > 0INT8U  OSQPostFront (OS_EVENT *pevent, void *msg){#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              */        OS_EventTaskRdy(pevent, msg, OS_STAT_Q);      /* Ready highest priority task waiting on event  */        OS_EXIT_CRITICAL();        OS_Sched();                                   /* Find highest priority task ready to run       */        return (OS_NO_ERR);