os_flag.c

UCOS/II for ICCAVR - The version of UCOS/II is 2.04 - the original port was done by Ole Saether

        return (pgrp);
    }
#if OS_ARG_CHK_EN > 0
    if (pgrp == (OS_FLAG_GRP *)0) {                        /* Validate 'pgrp'                          */
        *err = OS_FLAG_INVALID_PGRP;
        return (pgrp);
    }
#endif
    if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) {          /* Validate event group type                */
        *err = OS_ERR_EVENT_TYPE;
        return (pgrp);
    }
    OS_ENTER_CRITICAL();
    if (pgrp->OSFlagWaitList != (void *)0) {               /* See if any tasks waiting on event flags  */
        tasks_waiting = TRUE;                              /* Yes                                      */
    } else {
        tasks_waiting = FALSE;                             /* No                                       */
    }
    switch (opt) {
        case OS_DEL_NO_PEND:                               /* Delete group if no task waiting          */
             if (tasks_waiting == FALSE) {
#if OS_FLAG_NAME_SIZE > 1
                 pgrp->OSFlagName[0]  = '?';               /* Unknown name                             */
                 pgrp->OSFlagName[1]  = OS_ASCII_NUL;
#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();
                 *err                 = OS_NO_ERR;
                 return ((OS_FLAG_GRP *)0);                /* Event Flag Group has been deleted        */
             } else {
                 OS_EXIT_CRITICAL();
                 *err                 = OS_ERR_TASK_WAITING;
                 return (pgrp);
             }

        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        */
                 OS_FlagTaskRdy(pnode, (OS_FLAGS)0);
                 pnode = (OS_FLAG_NODE *)pnode->OSFlagNodeNext;
             }
#if OS_EVENT_NAME_SIZE > 1
             pgrp->OSFlagName[0]  = '?';                   /* Unknown name                             */
             pgrp->OSFlagName[1]  = OS_ASCII_NUL;
#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 == TRUE) {                  /* Reschedule only if task(s) were waiting  */
                 OS_Sched();                               /* Find highest priority task ready to run  */
             }
             *err = OS_NO_ERR;
             return ((OS_FLAG_GRP *)0);                    /* Event Flag Group has been deleted        */

        default:
             OS_EXIT_CRITICAL();
             *err = OS_ERR_INVALID_OPT;
             return (pgrp);
    }
}
#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 a pointer to an ASCII string that will receive the name of the event flag
*                        group.  The string must be able to hold at least OS_FLAG_NAME_SIZE characters.
*
*              err       is a pointer to an error code that can contain one of the following values:
*
*                        OS_NO_ERR                  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_FLAG_INVALID_PGRP       if you passed a NULL pointer for 'pgrp'
*
* Returns    : The length of the string or 0 if the 'pgrp' is a NULL pointer.
*********************************************************************************************************
*/

#if OS_FLAG_NAME_SIZE > 1
INT8U  OSFlagNameGet (OS_FLAG_GRP *pgrp, char *pname, INT8U *err)
{
#if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */
    OS_CPU_SR  cpu_sr;
#endif
    INT8U      len;


    OS_ENTER_CRITICAL();
#if OS_ARG_CHK_EN > 0
    if (pgrp == (OS_FLAG_GRP *)0) {              /* Is 'pgrp' a NULL pointer?                          */
        OS_EXIT_CRITICAL();                      /* Yes                                                */
        *err = OS_FLAG_INVALID_PGRP;
        return (0);
    }
    if (pname == (char *)0) {                    /* Is 'pname' a NULL pointer?                         */
        OS_EXIT_CRITICAL();                      /* Yes                                                */
        *err = OS_ERR_PNAME_NULL;
        return (0);
    }
#endif
    if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) {
        OS_EXIT_CRITICAL();
        *err = OS_ERR_EVENT_TYPE;
        return (0);
    }
    len  = OS_StrCopy(pname, pgrp->OSFlagName);  /* Copy name from OS_FLAG_GRP                         */
    OS_EXIT_CRITICAL();
    *err = OS_NO_ERR;
    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.  The string must be able to hold at least OS_FLAG_NAME_SIZE characters.
*
*              err       is a pointer to an error code that can contain one of the following values:
*
*                        OS_NO_ERR                  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_FLAG_INVALID_PGRP       if you passed a NULL pointer for 'pgrp'
*
* Returns    : None
*********************************************************************************************************
*/

#if OS_FLAG_NAME_SIZE > 1
void  OSFlagNameSet (OS_FLAG_GRP *pgrp, char *pname, INT8U *err)
{
#if OS_CRITICAL_METHOD == 3                      /* Allocate storage for CPU status register           */
    OS_CPU_SR  cpu_sr;
#endif
    INT8U      len;


    OS_ENTER_CRITICAL();
#if OS_ARG_CHK_EN > 0
    if (pgrp == (OS_FLAG_GRP *)0) {              /* Is 'pgrp' a NULL pointer?                          */
        OS_EXIT_CRITICAL();                      /* Yes                                                */
        *err = OS_FLAG_INVALID_PGRP;
        return;
    }
    if (pname == (char *)0) {                    /* Is 'pname' a NULL pointer?                         */
        OS_EXIT_CRITICAL();                      /* Yes                                                */
        *err = OS_ERR_PNAME_NULL;
        return;
    }
#endif
    if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) {
        OS_EXIT_CRITICAL();
        *err = OS_ERR_EVENT_TYPE;
        return;
    }
    len = OS_StrLen(pname);                      /* Can we fit the string in the storage area?         */
    if (len > (OS_FLAG_NAME_SIZE - 1)) {         /* No                                                 */
        OS_EXIT_CRITICAL();
        *err = OS_ERR_FLAG_NAME_TOO_LONG;
        return;
    } 
    (void)OS_StrCopy(pgrp->OSFlagName, pname);   /* Yes, copy name from OS_FLAG_GRP                    */
    OS_EXIT_CRITICAL();
    *err = OS_NO_ERR;
    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.
*
*              err           is a pointer to an error code and can be:
*                            OS_NO_ERR              The desired bits have been set within the specified
*                                                   'timeout'.
*                            OS_ERR_PEND_ISR        If you tried to PEND from an ISR
*                            OS_FLAG_INVALID_PGRP   If 'pgrp' is a NULL pointer.
*                            OS_ERR_EVENT_TYPE      You are not pointing to an event flag group
*                            OS_TIMEOUT             The bit(s) have not been set in the specified
*                                                   'timeout'.
*                            OS_FLAG_ERR_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, INT16U timeout, INT8U *err)
{
#if OS_CRITICAL_METHOD == 3                                /* Allocate storage for CPU status register */
    OS_CPU_SR     cpu_sr;
#endif
    OS_FLAG_NODE  node;
    OS_FLAGS      flags_rdy;
    BOOLEAN       consume;


    if (OSIntNesting > 0) {                                /* See if called from ISR ...               */
        *err = OS_ERR_PEND_ISR;                            /* ... can't PEND from an ISR               */
        return ((OS_FLAGS)0);
    }
#if OS_ARG_CHK_EN > 0
    if (pgrp == (OS_FLAG_GRP *)0) {                        /* Validate 'pgrp'                          */
        *err = OS_FLAG_INVALID_PGRP;
        return ((OS_FLAGS)0);
    }
#endif
    if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) {          /* Validate event block type                */
        *err = OS_ERR_EVENT_TYPE;
        return ((OS_FLAGS)0);
    }
    if (wait_type & OS_FLAG_CONSUME) {                     /* See if we need to consume the flags      */
        wait_type &= ~OS_FLAG_CONSUME;
        consume    = TRUE;
    } else {
        consume    = FALSE;
    }
/*$PAGE*/
    OS_ENTER_CRITICAL();
    switch (wait_type) {
        case OS_FLAG_WAIT_SET_ALL:                         /* See if all required flags are set        */