⭐ 欢迎来到虫虫下载站! | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站

📄 os_q.lst

📁 uCOS-II_2.52在51上的移植程序
💻 LST
📖 第 1 页 / 共 3 页
字号:
                           *err = OS_ERR_INVALID_OPT;
                           return (pevent);
                  }
              }
              #endif
C51 COMPILER V7.50   OS_Q                                                                  08/08/2005 11:36:50 PAGE 5   

              
              /*$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 > 0
              INT8U  OSQFlush (OS_EVENT *pevent)
              {
              
                  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
C51 COMPILER V7.50   OS_Q                                                                  08/08/2005 11:36:50 PAGE 6   

              *                            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)
              {
              
                  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                         */
C51 COMPILER V7.50   OS_Q                                                                  08/08/2005 11:36:50 PAGE 7   

                  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 > 0
              INT8U  OSQPost (OS_EVENT *pevent, void *msg)
              {
              
                  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*/
              /*
C51 COMPILER V7.50   OS_Q                                                                  08/08/2005 11:36:50 PAGE 8   

              *********************************************************************************************************
              *                                   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 > 0
              INT8U  OSQPostFront (OS_EVENT *pevent, void *msg)
              {
              
                  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);
                  }
                  if (pq->OSQOut == pq->OSQStart) {                 /* Wrap OUT ptr if we are at the 1st queue entry */
                      pq->OSQOut = pq->OSQEnd;
                  }

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -