os_flag.c

ucosii 实例

#if OS_CRITICAL_METHOD == 3u                               /* Allocate storage for CPU status register */
    OS_CPU_SR     cpu_sr = 0u;
#endif



#ifdef OS_SAFETY_CRITICAL
    if (perr == (INT8U *)0) {
        OS_SAFETY_CRITICAL_EXCEPTION();
    }
#endif

#if OS_ARG_CHK_EN > 0u
    if (pgrp == (OS_FLAG_GRP *)0) {                        /* Validate 'pgrp'                          */
        *perr = OS_ERR_FLAG_INVALID_PGRP;
        return (pgrp);
    }
#endif
    if (OSIntNesting > 0u) {                               /* See if called from ISR ...               */
        *perr = OS_ERR_DEL_ISR;                            /* ... can't DELETE from an ISR             */
        return (pgrp);
    }
    if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) {          /* Validate event group type                */
        *perr = OS_ERR_EVENT_TYPE;
        return (pgrp);
    }
    OS_ENTER_CRITICAL();
    if (pgrp->OSFlagWaitList != (void *)0) {               /* See if any tasks waiting on event flags  */
        tasks_waiting = OS_TRUE;                           /* Yes                                      */
    } else {
        tasks_waiting = OS_FALSE;                          /* No                                       */
    }
    switch (opt) {
        case OS_DEL_NO_PEND:                               /* Delete group if no task waiting          */
             if (tasks_waiting == OS_FALSE) {
#if OS_FLAG_NAME_EN > 0u
                 pgrp->OSFlagName     = (INT8U *)(void *)"?";
#endif
                 pgrp->OSFlagType     = OS_EVENT_TYPE_UNUSED;
                 pgrp->OSFlagWaitList = (void *)OSFlagFreeList; /* Return group to free list           */
                 pgrp->OSFlagFlags    = (OS_FLAGS)0;
                 OSFlagFreeList       = pgrp;
                 OS_EXIT_CRITICAL();
                 *perr                = OS_ERR_NONE;
                 pgrp_return          = (OS_FLAG_GRP *)0;  /* Event Flag Group has been deleted        */
             } else {
                 OS_EXIT_CRITICAL();
                 *perr                = OS_ERR_TASK_WAITING;
                 pgrp_return          = pgrp;
             }
             break;

        case OS_DEL_ALWAYS:                                /* Always delete the event flag group       */
             pnode = (OS_FLAG_NODE *)pgrp->OSFlagWaitList;
             while (pnode != (OS_FLAG_NODE *)0) {          /* Ready ALL tasks waiting for flags        */
                 (void)OS_FlagTaskRdy(pnode, (OS_FLAGS)0);
                 pnode = (OS_FLAG_NODE *)pnode->OSFlagNodeNext;
             }
#if OS_FLAG_NAME_EN > 0u
             pgrp->OSFlagName     = (INT8U *)(void *)"?";
#endif
             pgrp->OSFlagType     = OS_EVENT_TYPE_UNUSED;
             pgrp->OSFlagWaitList = (void *)OSFlagFreeList;/* Return group to free list                */
             pgrp->OSFlagFlags    = (OS_FLAGS)0;
             OSFlagFreeList       = pgrp;
             OS_EXIT_CRITICAL();
             if (tasks_waiting == OS_TRUE) {               /* Reschedule only if task(s) were waiting  */
                 OS_Sched();                               /* Find highest priority task ready to run  */
             }
             *perr = OS_ERR_NONE;
             pgrp_return          = (OS_FLAG_GRP *)0;      /* Event Flag Group has been deleted        */
             break;

        default:
             OS_EXIT_CRITICAL();
             *perr                = OS_ERR_INVALID_OPT;
             pgrp_return          = pgrp;
             break;
    }
    return (pgrp_return);
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
*                                 GET THE NAME OF AN EVENT FLAG GROUP
*
* Description: This function is used to obtain the name assigned to an event flag group
*
* Arguments  : pgrp      is a pointer to the event flag group.
*
*              pname     is pointer to a pointer to an ASCII string that will receive the name of the event flag
*                        group.
*
*              perr      is a pointer to an error code that can contain one of the following values:
*
*                        OS_ERR_NONE                if the requested task is resumed
*                        OS_ERR_EVENT_TYPE          if 'pevent' is not pointing to an event flag group
*                        OS_ERR_PNAME_NULL          You passed a NULL pointer for 'pname'
*                        OS_ERR_FLAG_INVALID_PGRP   if you passed a NULL pointer for 'pgrp'
*                        OS_ERR_NAME_GET_ISR        if you called this function from an ISR
*
* Returns    : The length of the string or 0 if the 'pgrp' is a NULL pointer.
*********************************************************************************************************
*/

#if OS_FLAG_NAME_EN > 0u
INT8U  OSFlagNameGet (OS_FLAG_GRP   *pgrp,
                      INT8U        **pname,
                      INT8U         *perr)
{
    INT8U      len;
#if OS_CRITICAL_METHOD == 3u                     /* Allocate storage for CPU status register           */
    OS_CPU_SR  cpu_sr = 0u;
#endif



#ifdef OS_SAFETY_CRITICAL
    if (perr == (INT8U *)0) {
        OS_SAFETY_CRITICAL_EXCEPTION();
    }
#endif

#if OS_ARG_CHK_EN > 0u
    if (pgrp == (OS_FLAG_GRP *)0) {              /* Is 'pgrp' a NULL pointer?                          */
        *perr = OS_ERR_FLAG_INVALID_PGRP;
        return (0u);
    }
    if (pname == (INT8U **)0) {                   /* Is 'pname' a NULL pointer?                         */
        *perr = OS_ERR_PNAME_NULL;
        return (0u);
    }
#endif
    if (OSIntNesting > 0u) {                     /* See if trying to call from an ISR                  */
        *perr = OS_ERR_NAME_GET_ISR;
        return (0u);
    }
    OS_ENTER_CRITICAL();
    if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) {
        OS_EXIT_CRITICAL();
        *perr = OS_ERR_EVENT_TYPE;
        return (0u);
    }
    *pname = pgrp->OSFlagName;
    len    = OS_StrLen(*pname);
    OS_EXIT_CRITICAL();
    *perr  = OS_ERR_NONE;
    return (len);
}
#endif

/*$PAGE*/
/*
*********************************************************************************************************
*                                 ASSIGN A NAME TO AN EVENT FLAG GROUP
*
* Description: This function assigns a name to an event flag group.
*
* Arguments  : pgrp      is a pointer to the event flag group.
*
*              pname     is a pointer to an ASCII string that will be used as the name of the event flag
*                        group.
*
*              perr      is a pointer to an error code that can contain one of the following values:
*
*                        OS_ERR_NONE                if the requested task is resumed
*                        OS_ERR_EVENT_TYPE          if 'pevent' is not pointing to an event flag group
*                        OS_ERR_PNAME_NULL          You passed a NULL pointer for 'pname'
*                        OS_ERR_FLAG_INVALID_PGRP   if you passed a NULL pointer for 'pgrp'
*                        OS_ERR_NAME_SET_ISR        if you called this function from an ISR
*
* Returns    : None
*********************************************************************************************************
*/

#if OS_FLAG_NAME_EN > 0u
void  OSFlagNameSet (OS_FLAG_GRP  *pgrp,
                     INT8U        *pname,
                     INT8U        *perr)
{
#if OS_CRITICAL_METHOD == 3u                     /* Allocate storage for CPU status register           */
    OS_CPU_SR  cpu_sr = 0u;
#endif



#ifdef OS_SAFETY_CRITICAL
    if (perr == (INT8U *)0) {
        OS_SAFETY_CRITICAL_EXCEPTION();
    }
#endif

#if OS_ARG_CHK_EN > 0u
    if (pgrp == (OS_FLAG_GRP *)0) {              /* Is 'pgrp' a NULL pointer?                          */
        *perr = OS_ERR_FLAG_INVALID_PGRP;
        return;
    }
    if (pname == (INT8U *)0) {                   /* Is 'pname' a NULL pointer?                         */
        *perr = OS_ERR_PNAME_NULL;
        return;
    }
#endif
    if (OSIntNesting > 0u) {                     /* See if trying to call from an ISR                  */
        *perr = OS_ERR_NAME_SET_ISR;
        return;
    }
    OS_ENTER_CRITICAL();
    if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) {
        OS_EXIT_CRITICAL();
        *perr = OS_ERR_EVENT_TYPE;
        return;
    }
    pgrp->OSFlagName = pname;
    OS_EXIT_CRITICAL();
    *perr            = OS_ERR_NONE;
    return;
}
#endif

/*$PAGE*/
/*
*********************************************************************************************************
*                                        WAIT ON AN EVENT FLAG GROUP
*
* Description: This function is called to wait for a combination of bits to be set in an event flag
*              group.  Your application can wait for ANY bit to be set or ALL bits to be set.
*
* Arguments  : pgrp          is a pointer to the desired event flag group.
*
*              flags         Is a bit pattern indicating which bit(s) (i.e. flags) you wish to wait for.
*                            The bits you want are specified by setting the corresponding bits in
*                            'flags'.  e.g. if your application wants to wait for bits 0 and 1 then
*                            'flags' would contain 0x03.
*
*              wait_type     specifies whether you want ALL bits to be set or ANY of the bits to be set.
*                            You can specify the following argument:
*
*                            OS_FLAG_WAIT_CLR_ALL   You will wait for ALL bits in 'mask' to be clear (0)
*                            OS_FLAG_WAIT_SET_ALL   You will wait for ALL bits in 'mask' to be set   (1)
*                            OS_FLAG_WAIT_CLR_ANY   You will wait for ANY bit  in 'mask' to be clear (0)
*                            OS_FLAG_WAIT_SET_ANY   You will wait for ANY bit  in 'mask' to be set   (1)
*
*                            NOTE: Add OS_FLAG_CONSUME if you want the event flag to be 'consumed' by
*                                  the call.  Example, to wait for any flag in a group AND then clear
*                                  the flags that are present, set 'wait_type' to:
*
*                                  OS_FLAG_WAIT_SET_ANY + OS_FLAG_CONSUME
*
*              timeout       is an optional timeout (in clock ticks) that your task will wait for the
*                            desired bit combination.  If you specify 0, however, your task will wait
*                            forever at the specified event flag group or, until a message arrives.
*
*              perr          is a pointer to an error code and can be:
*                            OS_ERR_NONE               The desired bits have been set within the specified
*                                                      'timeout'.
*                            OS_ERR_PEND_ISR           If you tried to PEND from an ISR
*                            OS_ERR_FLAG_INVALID_PGRP  If 'pgrp' is a NULL pointer.
*                            OS_ERR_EVENT_TYPE         You are not pointing to an event flag group
*                            OS_ERR_TIMEOUT            The bit(s) have not been set in the specified
*                                                      'timeout'.
*                            OS_ERR_PEND_ABORT         The wait on the flag was aborted.
*                            OS_ERR_FLAG_WAIT_TYPE     You didn't specify a proper 'wait_type' argument.
*
* Returns    : The flags in the event flag group that made the task ready or, 0 if a timeout or an error
*              occurred.
*
* Called from: Task ONLY
*
* Note(s)    : 1) IMPORTANT, the behavior of this function has changed from PREVIOUS versions.  The
*                 function NOW returns the flags that were ready INSTEAD of the current state of the
*                 event flags.
*********************************************************************************************************
*/

OS_FLAGS  OSFlagPend (OS_FLAG_GRP  *pgrp,
                      OS_FLAGS      flags,
                      INT8U         wait_type,
                      INT32U        timeout,
                      INT8U        *perr)
{
    OS_FLAG_NODE  node;
    OS_FLAGS      flags_rdy;
    INT8U         result;
    INT8U         pend_stat;
    BOOLEAN       consume;
#if OS_CRITICAL_METHOD == 3u                               /* Allocate storage for CPU status register */
    OS_CPU_SR     cpu_sr = 0u;
#endif



#ifdef OS_SAFETY_CRITICAL
    if (perr == (INT8U *)0) {
        OS_SAFETY_CRITICAL_EXCEPTION();
    }
#endif

#if OS_ARG_CHK_EN > 0u
    if (pgrp == (OS_FLAG_GRP *)0) {                        /* Validate 'pgrp'                          */
        *perr = OS_ERR_FLAG_INVALID_PGRP;
        return ((OS_FLAGS)0);
    }
#endif