/**
*******************************************************************************
* @file sem.c
* @version V1.12
* @date 2010.03.01
* @brief Semaphore management implementation code of CooCox CoOS kernel.
*******************************************************************************
* @copy
*
* INTERNAL FILE,DON'T PUBLIC.
*
* © COPYRIGHT 2009 CooCox
*******************************************************************************
*/
/*---------------------------- Include ---------------------------------------*/
#include
#if CFG_SEM_EN >0
/**
*******************************************************************************
* @brief Create a semaphore
* @param[in] initCnt Semaphore valid counter.
* @param[in] maxCnt Semaphore max initialize counter.
* @param[in] sortType Semaphore sort type.
* @param[out] None
* @retval E_CREATE_FAIL Create semaphore fail.
* @retval others Create semaphore successful.
*
* @par Description
* @details This function is called to create a semaphore.
*******************************************************************************
*/
OS_EventID CoCreateSem(U16 initCnt,U16 maxCnt,U8 sortType)
{
P_ECB pecb;
#if CFG_PAR_CHECKOUT_EN >0
if(initCnt > maxCnt)
{
return E_CREATE_FAIL; /* Invalid 'initCnt' or 'maxCnt' */
}
if ((sortType != EVENT_SORT_TYPE_FIFO) && (sortType != EVENT_SORT_TYPE_PRIO))
{
return E_CREATE_FAIL; /* Illegal sort type,return error */
}
#endif
/* Create a semaphore type event control block */
pecb = CreatEvent(EVENT_TYPE_SEM,sortType,NULL);
if(pecb == NULL) /* If failed to create event block */
{
return E_CREATE_FAIL;
}
pecb->eventCounter = initCnt;/* Initialize event block */
pecb->initialEventCounter = maxCnt;
return (pecb->id); /* Return event id */
}
/**
*******************************************************************************
* @brief Delete a semaphore
* @param[in] id Event ID which to be deleted.
* @param[in] opt Delete option.
* @arg == OPT_DEL_ANYWAY Delete semaphore always
* @arg == OPT_DEL_NO_PEND Delete semaphore only when no task pending on.
* @param[out] None
* @retval E_INVALID_ID Invalid event ID.
* @retval E_INVALID_PARAMETER Invalid parameter.
* @retval E_TASK_WAITTING Tasks waitting for the event,delete fail.
* @retval E_OK Event deleted successful.
*
* @par Description
* @details This function is called to delete a semaphore.
*
* @note
*******************************************************************************
*/
StatusType CoDelSem(OS_EventID id,U8 opt)
{
P_ECB pecb;
#if CFG_PAR_CHECKOUT_EN >0
if(id >= CFG_MAX_EVENT)
{
return E_INVALID_ID;
}
#endif
pecb = &EventTbl[id];
#if CFG_PAR_CHECKOUT_EN >0
if(pecb->eventType != EVENT_TYPE_SEM)
{
return E_INVALID_ID; /* The event type is not semaphore */
}
#endif
return (DeleteEvent(pecb,opt));/* Delete the semaphore event control block*/
}
/**
*******************************************************************************
* @brief Accept a semaphore without waitting
* @param[in] id Event ID
* @param[out] None
* @retval E_INVALID_ID Invalid event ID.
* @retval E_SEM_EMPTY No semaphore exist.
* @retval E_OK Get semaphore successful.
*
* @par Description
* @details This function is called accept a semaphore without waitting.
*******************************************************************************
*/
StatusType CoAcceptSem(OS_EventID id)
{
P_ECB pecb;
#if CFG_PAR_CHECKOUT_EN >0
if(id >= CFG_MAX_EVENT)
{
return E_INVALID_ID;
}
#endif
pecb = &EventTbl[id];
#if CFG_PAR_CHECKOUT_EN >0
if( pecb->eventType != EVENT_TYPE_SEM)
{
return E_INVALID_ID;
}
#endif
OsSchedLock();
if(pecb->eventCounter > 0) /* If semaphore is positive,resource available */
{
OsSchedUnlock();
pecb->eventCounter--; /* Decrement semaphore only if positive */
return E_OK;
}
else /* Resource is not available */
{
OsSchedUnlock();
return E_SEM_EMPTY;
}
}
/**
*******************************************************************************
* @brief wait for a semaphore
* @param[in] id Event ID.
* @param[in] timeout The longest time for writting semaphore.
* @para 0
* @para 0x1~0xff
* @param[out] None
* @retval E_CALL Error call in ISR.
* @retval E_INVALID_ID Invalid event ID.
* @retval E_TIMEOUT Semaphore was not received within the specified
* 'timeout' time.
* @retval E_OK The call was successful and your task owns the
* resource,or the event you are waiting for occurred.
*
* @par Description
* @details This function is called to waits for a semaphore.
* @note IF this function is called in ISR,nothing to do and return immediately.
*******************************************************************************
*/
StatusType CoPendSem(OS_EventID id,U32 timeout)
{
P_ECB pecb;
P_OSTCB curTCB;
if(OSIntNesting > 0) /* If the caller is ISR */
{
return E_CALL;
}
#if CFG_PAR_CHECKOUT_EN >0
if(id >= CFG_MAX_EVENT)
{
return E_INVALID_ID;
}
#endif
pecb = &EventTbl[id];
#if CFG_PAR_CHECKOUT_EN >0
if(pecb->eventType != EVENT_TYPE_SEM)
{
return E_INVALID_ID;
}
#endif
if(OSSchedLock != 0) /* Schdule is locked? */
{
return E_OS_IN_LOCK; /* Yes,error return */
}
if(pecb->eventCounter > 0) /* If semaphore is positive,resource available */
{
pecb->eventCounter--; /* Decrement semaphore only if positive */
return E_OK;
}
else /* Resource is not available */
{
curTCB = TCBRunning;
if(timeout == 0) /* If time-out is not configured */
{
EventTaskToWait(pecb,curTCB); /* Block task until event occurs */
curTCB->pmail = NULL;
return E_OK;
}
else /* If time-out is configured */
{
OsSchedLock();
/* Block task until event or timeout occurs */
EventTaskToWait(pecb,curTCB);
InsertDelayList(curTCB,timeout);
OsSchedUnlock();
if (curTCB->pmail == NULL) /* If pmail is NULL, time-out occurred*/
{
return E_TIMEOUT;
}
else /* Event occurred or event have been deleted*/
{
curTCB->pmail = NULL;
return E_OK;
}
}
}
}
/**
*******************************************************************************
* @brief Post a semaphore
* @param[in] id id of event control block associated with the desired semaphore.
* @param[out] None
* @retval E_INVALID_ID Parameter id passed was invalid event ID.
* @retval E_SEM_FULL Semaphore full.
* @retval E_OK Semaphore had post successful.
*
* @par Description
* @details This function is called to post a semaphore to corresponding event.
*
* @note
*******************************************************************************
*/
StatusType CoPostSem(OS_EventID id)
{
P_ECB pecb;
#if CFG_PAR_CHECKOUT_EN >0
if(id >= CFG_MAX_EVENT)
{
return E_INVALID_ID;
}
#endif
pecb = &EventTbl[id];
#if CFG_PAR_CHECKOUT_EN >0
if(pecb->eventType != EVENT_TYPE_SEM) /* Invalid event control block type */
{
return E_INVALID_ID;
}
#endif
/* Make sure semaphore will not overflow */
if(pecb->eventCounter == pecb->initialEventCounter)
{
return E_SEM_FULL; /* The counter of Semaphore reach the max number*/
}
OsSchedLock();
pecb->eventCounter++; /* Increment semaphore count to register event */
EventTaskToRdy(pecb); /* Check semaphore event waiting list */
OsSchedUnlock();
return E_OK;
}
/**
*******************************************************************************
* @brief Post a semaphore in ISR
* @param[in] id identifier of event control block associated with the
* desired semaphore.
* @param[out] None
* @retval E_INVALID_ID Parameter id passed was invalid event ID.
* @retval E_NO_TASK_WAITTING There are one more tasks waitting for the event.
* @retval E_OK Semaphore had signaled successful.
*
* @par Description
* @details This function is called in ISR to post a semaphore to corresponding
* event.
* @note
*******************************************************************************
*/
#if CFG_MAX_SERVICE_REQUEST > 0
StatusType isr_PostSem(OS_EventID id)
{
if(OSSchedLock > 0) /* If scheduler is locked,(the caller is ISR) */
{
/* Initiate a post service handling request */
if(InsertInSRQ(SEM_REQ,id,NULL) == FALSE)
{
return E_SEV_REQ_FULL; /* If service request queue is full */
}
else /* Operate successfully */
{
return E_OK;
}
}
else
{
return(CoPostSem(id)); /* Post semaphore */
}
}
#endif
#endif