zownerqueue.c

zilog的实时操作系统RZK,可以移植到多种处理器上

/*
* File				:	zOwnerQueue.c
*
* Description		:	This file contains definition of functions related to ownerqueue.
*
* Copyright 2004 ZiLOG Inc.  ALL RIGHTS RESERVED.
*
* This file contains unpublished confidential and proprietary information
* of ZiLOG, Inc.
* NO PART OF THIS WORK MAY BE DUPLICATED, STORED, PUBLISHED OR DISCLOSED 
* IN ANY FORM WITHOUT THE PRIOR WRITTEN CONSENT OF ZiLOG, INC.
* This is not a license and no use of any kind of this work is authorized
* in the absence of a written license granted by ZiLOG, Inc. in ZiLOG's 
* sole discretion 
*/
#include "ZSysgen.h"
#include "ZTypes.h"
#include "ZThread.h"
#include "ZQueue.h"
#include "ZSemaphore.h"

#define pThread ((RZK_TCB_t*)hThread)
#define pSemaphore ((RZK_SEMAPHORE_t *)hSemaphore)

/* Function			:	zOwnerQueue
*
* Description		:	Adds a Thread to the ownerqueue
* 
* Inputs			:	hThread - Specifies the thread handle
*						hSemaphore - Specifies the semaphore pointer
*
* Outputs			:	void.
*							
*
* Dependencies		:	None.
*/
void AddToOwnerQueue(RZK_HANDLE_t hThread,RZK_SEMAPHORE_t* hSemaphore)
{
	/* LOCAL VARIABLES*/
	RZK_SEMAPHORE_t *pTempObject,*pTempObject2;

	if(pThread->pOwnedResNext == NULL)
	{
		/* Every TCB contains it's own variable which indicates whether the current thrad is the
		owner of any object */
		pThread->pOwnedResNext = hSemaphore;
		pSemaphore->pOwnedResNext = ( RZK_SEMAPHORE_t * ) NULL;
		return;
	}

	pTempObject = ( RZK_SEMAPHORE_t * ) pThread->pOwnedResNext;
	while(pTempObject != NULL)
	{
		pTempObject2 = pTempObject;
		pTempObject = pTempObject->pOwnedResNext;
	}
	pSemaphore->pOwnedResNext = pTempObject2->pOwnedResNext;
	pTempObject2->pOwnedResNext = pSemaphore;
}/* end of AddToOwnerQueue */




/*
* File				:	zOwnerQueue.c	
*
* Function			:	RemoveFromOwnerQueue
*
* Description		:	Removes a Thread from ownerqueue
* 
* Inputs			:	hThread - Specifies the thread handle
*						hSemaphore - Specifies the semaphore pointer
*
* Outputs			:	void.
*
* Dependencies		:	None.
*
*/

/* Remove From Owner Queue function */

void RemoveFromOwnerQueue(RZK_HANDLE_t hThread,RZK_SEMAPHORE_t* hSemaphore)
{
	/* LOCAL VARIABLES */
	RZK_SEMAPHORE_t *pTempObject,*pTempObject2;
	
	#ifdef RZK_DEBUG
		if(pThread == NULL)
			return;
	#endif
	/* Once a thread is removed from owner queue then another thread 
	waiting in queue becomes owner automatically */
	if (pThread->pOwnedResNext == pSemaphore)
	{
		/* if this is the first object in queue to be removed */
		pThread->pOwnedResNext = pSemaphore-> pOwnedResNext;
		return;
	}

	pTempObject = ( RZK_SEMAPHORE_t * ) pThread->pOwnedResNext;
	while(pTempObject != hSemaphore)
	{
		pTempObject2 = pTempObject;
		pTempObject = pTempObject->pOwnedResNext;
	}
	pTempObject2->pOwnedResNext = pTempObject->pOwnedResNext;
	
} /* end of RemoveFromOwnerQueue */