?? os_flag.c
?? ucos_vc.rar
?? C
?? 第 1 頁 / 共 3 頁
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??
OS_EXIT_CRITICAL();
*err = OS_ERR_TASK_WAITING;
return (pgrp);
}
case OS_DEL_ALWAYS: /* Always delete the event flag group */
pnode = pgrp->OSFlagWaitList;
while (pnode != (OS_FLAG_NODE *)0) { /* Ready ALL tasks waiting for flags */
OS_FlagTaskRdy(pnode, (OS_FLAGS)0);
pnode = pnode->OSFlagNodeNext;
}
pgrp->OSFlagType = OS_EVENT_TYPE_UNUSED;
pgrp->OSFlagWaitList = (void *)OSFlagFreeList;/* Return group to free list */
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*/
/*
*********************************************************************************************************
* 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 new state of the flags in the event flag group when the task is resumed or,
* 0 if a timeout or an error occurred.
*
* Called from: Task ONLY
*********************************************************************************************************
*/
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_cur;
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);
}
if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) { /* Validate event block type */
*err = OS_ERR_EVENT_TYPE;
return ((OS_FLAGS)0);
}
#endif
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 */
flags_rdy = pgrp->OSFlagFlags & flags; /* Extract only the bits we want */
if (flags_rdy == flags) { /* Must match ALL the bits that we want */
if (consume == TRUE) { /* See if we need to consume the flags */
pgrp->OSFlagFlags &= ~flags_rdy; /* Clear ONLY the flags that we wanted */
}
flags_cur = pgrp->OSFlagFlags; /* Will return the state of the group */
OS_EXIT_CRITICAL(); /* Yes, condition met, return to caller */
*err = OS_NO_ERR;
return (flags_cur);
} else { /* Block task until events occur or timeout */
OS_FlagBlock(pgrp, &node, flags, wait_type, timeout);
OS_EXIT_CRITICAL();
}
break;
case OS_FLAG_WAIT_SET_ANY:
flags_rdy = pgrp->OSFlagFlags & flags; /* Extract only the bits we want */
if (flags_rdy != (OS_FLAGS)0) { /* See if any flag set */
if (consume == TRUE) { /* See if we need to consume the flags */
pgrp->OSFlagFlags &= ~flags_rdy; /* Clear ONLY the flags that we got */
}
flags_cur = pgrp->OSFlagFlags; /* Will return the state of the group */
OS_EXIT_CRITICAL(); /* Yes, condition met, return to caller */
*err = OS_NO_ERR;
return (flags_cur);
} else { /* Block task until events occur or timeout */
OS_FlagBlock(pgrp, &node, flags, wait_type, timeout);
OS_EXIT_CRITICAL();
}
break;
#if OS_FLAG_WAIT_CLR_EN > 0
case OS_FLAG_WAIT_CLR_ALL: /* See if all required flags are cleared */
flags_rdy = ~pgrp->OSFlagFlags & flags; /* Extract only the bits we want */
if (flags_rdy == flags) { /* Must match ALL the bits that we want */
if (consume == TRUE) { /* See if we need to consume the flags */
pgrp->OSFlagFlags |= flags_rdy; /* Set ONLY the flags that we wanted */
}
flags_cur = pgrp->OSFlagFlags; /* Will return the state of the group */
OS_EXIT_CRITICAL(); /* Yes, condition met, return to caller */
*err = OS_NO_ERR;
return (flags_cur);
} else { /* Block task until events occur or timeout */
OS_FlagBlock(pgrp, &node, flags, wait_type, timeout);
OS_EXIT_CRITICAL();
}
break;
case OS_FLAG_WAIT_CLR_ANY:
flags_rdy = ~pgrp->OSFlagFlags & flags; /* Extract only the bits we want */
if (flags_rdy != (OS_FLAGS)0) { /* See if any flag cleared */
if (consume == TRUE) { /* See if we need to consume the flags */
pgrp->OSFlagFlags |= flags_rdy; /* Set ONLY the flags that we got */
}
flags_cur = pgrp->OSFlagFlags; /* Will return the state of the group */
OS_EXIT_CRITICAL(); /* Yes, condition met, return to caller */
*err = OS_NO_ERR;
return (flags_cur);
} else { /* Block task until events occur or timeout */
OS_FlagBlock(pgrp, &node, flags, wait_type, timeout);
OS_EXIT_CRITICAL();
}
break;
#endif
default:
OS_EXIT_CRITICAL();
flags_cur = (OS_FLAGS)0;
*err = OS_FLAG_ERR_WAIT_TYPE;
return (flags_cur);
}
OS_Sched(); /* Find next HPT ready to run */
OS_ENTER_CRITICAL();
if (OSTCBCur->OSTCBStat & OS_STAT_FLAG) { /* Have we timed-out? */
OS_FlagUnlink(&node);
OSTCBCur->OSTCBStat = OS_STAT_RDY; /* Yes, make task ready-to-run */
OS_EXIT_CRITICAL();
flags_cur = (OS_FLAGS)0;
*err = OS_TIMEOUT; /* Indicate that we timed-out waiting */
} else {
if (consume == TRUE) { /* See if we need to consume the flags */
switch (wait_type) {
case OS_FLAG_WAIT_SET_ALL:
case OS_FLAG_WAIT_SET_ANY: /* Clear ONLY the flags we got */
pgrp->OSFlagFlags &= ~OSTCBCur->OSTCBFlagsRdy;
break;
#if OS_FLAG_WAIT_CLR_EN > 0
case OS_FLAG_WAIT_CLR_ALL:
case OS_FLAG_WAIT_CLR_ANY: /* Set ONLY the flags we got */
pgrp->OSFlagFlags |= OSTCBCur->OSTCBFlagsRdy;
break;
#endif
}
}
flags_cur = pgrp->OSFlagFlags;
OS_EXIT_CRITICAL();
*err = OS_NO_ERR; /* Event(s) must have occurred */
}
return (flags_cur);
}
/*$PAGE*/
/*
*********************************************************************************************************
* POST EVENT FLAG BIT(S)
*
* Description: This function is called to set or clear some bits in an event flag group. The bits to
* set or clear are specified by a 'bit mask'.
*
* Arguments : pgrp is a pointer to the desired event flag group.
*
* flags If 'opt' (see below) is OS_FLAG_SET, each bit that is set in 'flags' will
* set the corresponding bit in the event flag group. e.g. to set bits 0, 4
* and 5 you would set 'flags' to:
*
* 0x31 (note, bit 0 is least significant bit)
*
* If 'opt' (see below) is OS_FLAG_CLR, each bit that is set in 'flags' will
* CLEAR the corresponding bit in the event flag group. e.g. to clear bits 0,
* 4 and 5 you would specify 'flags' as:
*
* 0x31 (note, bit 0 is least significant bit)
*
* opt indicates whether the flags will be:
* set (OS_FLAG_SET) or
* cleared (OS_FLAG_CLR)
*
* err is a pointer to an error code and can be:
* OS_NO_ERR The call was successfull
* OS_FLAG_INVALID_PGRP You passed a NULL pointer
* OS_ERR_EVENT_TYPE You are not pointing to an event flag group
* OS_FLAG_INVALID_OPT You specified an invalid option
*
* Returns : the new value of the event flags bits that are still set.
*
* Called From: Task or ISR
*
* WARNING(s) : 1) The execution time of this function depends on the number of tasks waiting on the event
* flag group.
* 2) The amount of time interrupts are DISABLED depends on the number of tasks waiting on
* the event flag group.
*********************************************************************************************************
*/
OS_FLAGS OSFlagPost (OS_FLAG_GRP *pgrp, OS_FLAGS flags, INT8U opt, INT8U *err)
{
#if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr;
#endif
OS_FLAG_NODE *pnode;
BOOLEAN sched;
OS_FLAGS flags_cur;
OS_FLAGS flags_rdy;
#if OS_ARG_CHK_EN > 0
if (pgrp == (OS_FLAG_GRP *)0) { /* Validate 'pgrp' */
*err = OS_FLAG_INVALID_PGRP;
return ((OS_FLAGS)0);
}
if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) { /* Make sure we are pointing to an event flag grp */
*err = OS_ERR_EVENT_TYPE;
return ((OS_FLAGS)0);
}
#endif
/*$PAGE*/
OS_ENTER_CRITICAL();
switch (opt) {
case OS_FLAG_CLR:
pgrp->OSFlagFlags &= ~flags; /* Clear the flags specified in the group */
break;
case OS_FLAG_SET:
pgrp->OSFlagFlags |= flags; /* Set the flags specified in the group */
break;
default:
OS_EXIT_CRITICAL(); /* INVALID option */
*err = OS_FLAG_INVALID_OPT;
return ((OS_FLAGS)0);
}
sched = FALSE; /* Indicate that we don't need rescheduling */
pnode = pgrp->OSFlagWaitList;
while (pnode != (OS_FLAG_NODE *)0) { /* Go through all tasks waiting on event flag(s) */
switch (pnode->OSFlagNodeWaitType) {
case OS_FLAG_WAIT_SET_ALL: /* See if all req. flags are set for current node */
flags_rdy = pgrp->OSFlagFlags & pnode->OSFlagNodeFlags;
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