os_mbox.c

完整的ucos实例

        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_MBOX) {  /* Validate event block type                     */ 
        *err = OS_ERR_EVENT_TYPE; 
        return ((void *)0); 
    } 
#endif 
    OS_ENTER_CRITICAL(); 
    msg = pevent->OSEventPtr; 
    if (msg != (void *)0) {                           /* See if there is already a message             */ 
        pevent->OSEventPtr = (void *)0;               /* Clear the mailbox                             */ 
        OS_EXIT_CRITICAL(); 
        *err = OS_NO_ERR; 
        return (msg);                                 /* Return the message received (or NULL)         */ 
    } 
    OSTCBCur->OSTCBStat |= OS_STAT_MBOX;              /* Message not available, task will pend         */ 
    OSTCBCur->OSTCBDly   = timeout;                   /* Load timeout in 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) {                           /* See if we were given the message              */ 
        OSTCBCur->OSTCBMsg      = (void *)0;          /* Yes, clear message received                   */ 
        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 the message received                   */ 
    } 
    OS_EventTO(pevent);                               /* Timed out, Make task ready                    */ 
    OS_EXIT_CRITICAL(); 
    *err = OS_TIMEOUT;                                /* Indicate that a timeout occured               */ 
    return ((void *)0);                               /* Return a NULL message                         */ 
} 
/*$PAGE*/ 
/* 
********************************************************************************************************* 
*                                       POST MESSAGE TO A MAILBOX 
* 
* Description: This function sends a message to a mailbox 
* 
* Arguments  : pevent        is a pointer to the event control block associated with the desired mailbox 
* 
*              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_MBOX_FULL         If the mailbox already contains a message.  You can can only send one 
*                                   message at a time and thus, the message MUST be consumed before you 
*                                   are allowed to send another one. 
*              OS_ERR_EVENT_TYPE    If you are attempting to post to a non mailbox. 
*              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_MBOX_POST_EN > 0 
INT8U  OSMboxPost (OS_EVENT *pevent, void *msg) 
{ 
#if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */ 
    OS_CPU_SR  cpu_sr; 
#endif     
     
     
#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_MBOX) {  /* Validate event block type                     */ 
        return (OS_ERR_EVENT_TYPE); 
    } 
#endif 
    OS_ENTER_CRITICAL(); 
    if (pevent->OSEventGrp != 0x00) {                 /* See if any task pending on mailbox            */ 
        OS_EventTaskRdy(pevent, msg, OS_STAT_MBOX);   /* Ready highest priority task waiting on event  */ 
        OS_EXIT_CRITICAL(); 
        OS_Sched();                                   /* Find highest priority task ready to run       */ 
        return (OS_NO_ERR); 
    } 
    if (pevent->OSEventPtr != (void *)0) {            /* Make sure mailbox doesn't already have a msg  */ 
        OS_EXIT_CRITICAL(); 
        return (OS_MBOX_FULL); 
    } 
    pevent->OSEventPtr = msg;                         /* Place message in mailbox                      */ 
    OS_EXIT_CRITICAL(); 
    return (OS_NO_ERR); 
} 
#endif 
 
/*$PAGE*/ 
/* 
********************************************************************************************************* 
*                                       POST MESSAGE TO A MAILBOX 
* 
* Description: This function sends a message to a mailbox 
* 
* Arguments  : pevent        is a pointer to the event control block associated with the desired mailbox 
* 
*              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 OSMboxPost()) 
*                            OS_POST_OPT_BROADCAST    POST to ALL tasks that are waiting on the mailbox 
* 
* Returns    : OS_NO_ERR            The call was successful and the message was sent 
*              OS_MBOX_FULL         If the mailbox already contains a message.  You can can only send one 
*                                   message at a time and thus, the message MUST be consumed before you 
*                                   are allowed to send another one. 
*              OS_ERR_EVENT_TYPE    If you are attempting to post to a non mailbox. 
*              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 mailbox. 
********************************************************************************************************* 
*/ 
 
#if OS_MBOX_POST_OPT_EN > 0 
INT8U  OSMboxPostOpt (OS_EVENT *pevent, void *msg, INT8U opt) 
{ 
#if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */ 
    OS_CPU_SR  cpu_sr; 
#endif     
     
     
#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_MBOX) {  /* Validate event block type                     */ 
        return (OS_ERR_EVENT_TYPE); 
    } 
#endif 
    OS_ENTER_CRITICAL(); 
    if (pevent->OSEventGrp != 0x00) {                 /* See if any task pending on mailbox            */ 
        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 mailbox     */            
                OS_EventTaskRdy(pevent, msg, OS_STAT_MBOX);     
            } 
        } else { 
            OS_EventTaskRdy(pevent, msg, OS_STAT_MBOX);    /* No,  Post to HPT waiting on mbox         */ 
        } 
        OS_EXIT_CRITICAL(); 
        OS_Sched();                                        /* Find highest priority task ready to run  */ 
        return (OS_NO_ERR); 
    } 
    if (pevent->OSEventPtr != (void *)0) {            /* Make sure mailbox doesn't already have a msg  */ 
        OS_EXIT_CRITICAL(); 
        return (OS_MBOX_FULL); 
    } 
    pevent->OSEventPtr = msg;                         /* Place message in mailbox                      */ 
    OS_EXIT_CRITICAL(); 
    return (OS_NO_ERR); 
} 
#endif 
 
/*$PAGE*/ 
/* 
********************************************************************************************************* 
*                                        QUERY A MESSAGE MAILBOX 
* 
* Description: This function obtains information about a message mailbox. 
* 
* Arguments  : pevent        is a pointer to the event control block associated with the desired mailbox 
* 
*              pdata         is a pointer to a structure that will contain information about the message 
*                            mailbox. 
* 
* 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 mailbox. 
*              OS_ERR_PEVENT_NULL  If 'pevent' is a NULL pointer 
********************************************************************************************************* 
*/ 
 
#if OS_MBOX_QUERY_EN > 0 
INT8U  OSMboxQuery (OS_EVENT *pevent, OS_MBOX_DATA *pdata) 
{ 
#if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */ 
    OS_CPU_SR  cpu_sr; 
#endif     
    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_MBOX) {       /* Validate event block type                */ 
        return (OS_ERR_EVENT_TYPE); 
    } 
#endif 
    OS_ENTER_CRITICAL(); 
    pdata->OSEventGrp = pevent->OSEventGrp;                /* Copy message mailbox 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 
    pdata->OSMsg = pevent->OSEventPtr;                     /* Get message from mailbox                 */ 
    OS_EXIT_CRITICAL(); 
    return (OS_NO_ERR); 
} 
#endif                                                     /* OS_MBOX_QUERY_EN                         */ 
#endif                                                     /* OS_MBOX_EN                               */