os_q.c

完整的ucos实例

    } 
    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                                  */