OS_Q.C
上传用户:zfj3589
上传日期:2022-07-13
资源大小:635k
文件大小:34k
- /*
- *********************************************************************************************************
- * uC/OS-II
- * The Real-Time Kernel
- * MESSAGE QUEUE MANAGEMENT
- *
- * (c) Copyright 1992-2001, Jean J. Labrosse, Weston, FL
- * All Rights Reserved
- *
- * File : OS_Q.C
- * By : Jean J. Labrosse
- *********************************************************************************************************
- */
- #ifndef OS_MASTER_FILE
- #include "includes.h"
- #endif
- #if (OS_Q_EN > 0) && (OS_MAX_QS > 0)
- /*
- *********************************************************************************************************
- * ACCEPT MESSAGE FROM QUEUE
- *
- * Description: This function checks the queue to see if a message is available. Unlike OSQPend(),
- * OSQAccept() does not suspend the calling task if a message is not available.
- *
- * Arguments : pevent is a pointer to the event control block
- *
- * Returns : != (void *)0 is the message in the queue if one is available. The message is removed
- * from the so the next time OSQAccept() is called, the queue will contain
- * one less entry.
- * == (void *)0 if the queue is empty or,
- * if 'pevent' is a NULL pointer or,
- * if you passed an invalid event type
- *********************************************************************************************************
- */
- #if OS_Q_ACCEPT_EN > 0
- void *OSQAccept (OS_EVENT *pevent)
- {
- #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
- OS_CPU_SR cpu_sr;
- #endif
- void *msg;
- OS_Q *pq;
- #if OS_ARG_CHK_EN > 0
- if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
- return ((void *)0);
- }
- if (pevent->OSEventType != OS_EVENT_TYPE_Q) {/* Validate event block 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;
- }
- } else {
- msg = (void *)0; /* Queue is empty */
- }
- OS_EXIT_CRITICAL();
- return (msg); /* Return message received (or NULL) */
- }
- #endif
- /*$PAGE*/
- /*
- *********************************************************************************************************
- * CREATE A MESSAGE QUEUE
- *
- * Description: This function creates a message queue if free event control blocks are available.
- *
- * Arguments : start is a pointer to the base address of the message queue storage area. The
- * storage area MUST be declared as an array of pointers to 'void' as follows
- *
- * void *MessageStorage[size]
- *
- * size is the number of elements in the storage area
- *
- * Returns : != (OS_EVENT *)0 is a pointer to the event control clock (OS_EVENT) associated with the
- * created queue
- * == (OS_EVENT *)0 if no event control blocks were available or an error was detected
- *********************************************************************************************************
- */
- OS_EVENT *OSQCreate (void **start, INT16U size)
- {
- #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
- OS_CPU_SR cpu_sr;
- #endif
- OS_EVENT *pevent;
- OS_Q *pq;
- if (OSIntNesting > 0) { /* See if called from ISR ... */
- return ((OS_EVENT *)0); /* ... can't CREATE from an ISR */
- }
- OS_ENTER_CRITICAL();
- pevent = OSEventFreeList; /* Get next free event control block */
- if (OSEventFreeList != (OS_EVENT *)0) { /* See if pool of free ECB pool was empty */
- OSEventFreeList = (OS_EVENT *)OSEventFreeList->OSEventPtr;
- }
- OS_EXIT_CRITICAL();
- if (pevent != (OS_EVENT *)0) { /* See if we have an event control block */
- OS_ENTER_CRITICAL(); /* Get a free queue control block */
- pq = OSQFreeList;
- if (OSQFreeList != (OS_Q *)0) {
- OSQFreeList = OSQFreeList->OSQPtr;
- }
- OS_EXIT_CRITICAL();
- if (pq != (OS_Q *)0) { /* See if we were able to get a queue control block */
- pq->OSQStart = start; /* Yes, initialize the queue */
- pq->OSQEnd = &start[size];
- pq->OSQIn = start;
- pq->OSQOut = start;
- pq->OSQSize = size;
- pq->OSQEntries = 0;
- pevent->OSEventType = OS_EVENT_TYPE_Q;
- pevent->OSEventPtr = pq;
- OS_EventWaitListInit(pevent);
- } else { /* No, since we couldn't get a queue control block */
- OS_ENTER_CRITICAL(); /* Return event control block on error */
- pevent->OSEventPtr = (void *)OSEventFreeList;
- OSEventFreeList = pevent;
- OS_EXIT_CRITICAL();
- pevent = (OS_EVENT *)0;
- }
- }
- return (pevent);
- }
- /*$PAGE*/
- /*
- *********************************************************************************************************
- * DELETE A MESSAGE QUEUE
- *
- * Description: This function deletes a message queue and readies all tasks pending on the queue.
- *
- * Arguments : pevent is a pointer to the event control block associated with the desired
- * queue.
- *
- * opt determines delete options as follows:
- * opt == OS_DEL_NO_PEND Delete the queue ONLY if no task pending
- * opt == OS_DEL_ALWAYS Deletes the queue even if tasks are waiting.
- * In this case, all the tasks pending will be readied.
- *
- * err is a pointer to an error code that can contain one of the following values:
- * OS_NO_ERR The call was successful and the queue was deleted
- * OS_ERR_DEL_ISR If you tried to delete the queue from an ISR
- * OS_ERR_INVALID_OPT An invalid option was specified
- * OS_ERR_TASK_WAITING One or more tasks were waiting on the queue
- * OS_ERR_EVENT_TYPE If you didn't pass a pointer to a queue
- * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer.
- *
- * Returns : pevent upon error
- * (OS_EVENT *)0 if the queue was successfully deleted.
- *
- * Note(s) : 1) This function must be used with care. Tasks that would normally expect the presence of
- * the queue MUST check the return code of OSQPend().
- * 2) OSQAccept() callers will not know that the intended queue has been deleted unless
- * they check 'pevent' to see that it's a NULL pointer.
- * 3) This call can potentially disable interrupts for a long time. The interrupt disable
- * time is directly proportional to the number of tasks waiting on the queue.
- * 4) Because ALL tasks pending on the queue will be readied, you MUST be careful in
- * applications where the queue is used for mutual exclusion because the resource(s)
- * will no longer be guarded by the queue.
- * 5) If the storage for the message queue was allocated dynamically (i.e. using a malloc()
- * type call) then your application MUST release the memory storage by call the counterpart
- * call of the dynamic allocation scheme used. If the queue storage was created statically
- * then, the storage can be reused.
- *********************************************************************************************************
- */
- #if OS_Q_DEL_EN > 0
- OS_EVENT *OSQDel (OS_EVENT *pevent, INT8U opt, INT8U *err)
- {
- #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
- OS_CPU_SR cpu_sr;
- #endif
- BOOLEAN tasks_waiting;
- OS_Q *pq;
- if (OSIntNesting > 0) { /* See if called from ISR ... */
- *err = OS_ERR_DEL_ISR; /* ... can't DELETE from an ISR */
- return ((OS_EVENT *)0);
- }
- #if OS_ARG_CHK_EN > 0
- if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
- *err = OS_ERR_PEVENT_NULL;
- return (pevent);
- }
- if (pevent->OSEventType != OS_EVENT_TYPE_Q) { /* Validate event block type */
- *err = OS_ERR_EVENT_TYPE;
- return (pevent);
- }
- #endif
- OS_ENTER_CRITICAL();
- if (pevent->OSEventGrp != 0x00) { /* See if any tasks waiting on queue */
- tasks_waiting = TRUE; /* Yes */
- } else {
- tasks_waiting = FALSE; /* No */
- }
- switch (opt) {
- case OS_DEL_NO_PEND: /* Delete queue only if no task waiting */
- if (tasks_waiting == FALSE) {
- pq = pevent->OSEventPtr; /* Return OS_Q to free list */
- pq->OSQPtr = OSQFreeList;
- OSQFreeList = pq;
- pevent->OSEventType = OS_EVENT_TYPE_UNUSED;
- pevent->OSEventPtr = OSEventFreeList; /* Return Event Control Block to free list */
- OSEventFreeList = pevent; /* Get next free event control block */
- OS_EXIT_CRITICAL();
- *err = OS_NO_ERR;
- return ((OS_EVENT *)0); /* Queue has been deleted */
- } else {
- OS_EXIT_CRITICAL();
- *err = OS_ERR_TASK_WAITING;
- return (pevent);
- }
- case OS_DEL_ALWAYS: /* Always delete the queue */
- while (pevent->OSEventGrp != 0x00) { /* Ready ALL tasks waiting for queue */
- OS_EventTaskRdy(pevent, (void *)0, OS_STAT_Q);
- }
- pq = pevent->OSEventPtr; /* Return OS_Q to free list */
- pq->OSQPtr = OSQFreeList;
- OSQFreeList = pq;
- pevent->OSEventType = OS_EVENT_TYPE_UNUSED;
- pevent->OSEventPtr = OSEventFreeList; /* Return Event Control Block to free list */
- OSEventFreeList = pevent; /* Get next free event control block */
- OS_EXIT_CRITICAL();
- if (tasks_waiting == TRUE) { /* Reschedule only if task(s) were waiting */
- OS_Sched(); /* Find highest priority task ready to run */
- }
- *err = OS_NO_ERR;
- return ((OS_EVENT *)0); /* Queue has been deleted */
- default:
- OS_EXIT_CRITICAL();
- *err = OS_ERR_INVALID_OPT;
- return (pevent);
- }
- }
- #endif
- /*$PAGE*/
- /*
- *********************************************************************************************************
- * FLUSH QUEUE
- *
- * Description : This function is used to flush the contents of the message queue.
- *
- * Arguments : none
- *
- * Returns : OS_NO_ERR upon success
- * OS_ERR_EVENT_TYPE If you didn't pass a pointer to a queue
- * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer
- *********************************************************************************************************
- */
- #if OS_Q_FLUSH_EN > 0
- INT8U OSQFlush (OS_EVENT *pevent)
- {
- #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
- OS_CPU_SR cpu_sr;
- #endif
- OS_Q *pq;
- #if OS_ARG_CHK_EN > 0
- if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
- return (OS_ERR_PEVENT_NULL);
- }
- if (pevent->OSEventType != OS_EVENT_TYPE_Q) { /* Validate event block type */
- return (OS_ERR_EVENT_TYPE);
- }
- #endif
- OS_ENTER_CRITICAL();
- pq = (OS_Q *)pevent->OSEventPtr; /* Point to queue storage structure */
- pq->OSQIn = pq->OSQStart;
- pq->OSQOut = pq->OSQStart;
- pq->OSQEntries = 0;
- OS_EXIT_CRITICAL();
- return (OS_NO_ERR);
- }
- #endif
- /*$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 > 0
- INT8U 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 > 0
- INT8U 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);
- }
- 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 */