initializecircularbuffer.c

zilog的实时操作系统RZK,可以移植到多种处理器上

/*
* File			: InitializeCircularBuffer.c
*
* Description	: This file contains InitializeCircularBuffer function.
*
* 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* This file contains unpublished confidential and proprietary information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 "ZInterrupt.h"
#include "ZMessageQ.h"


/*
* Function		:	InitializeCircularBuffer
*
* Description	:	This function Initializes the  starting,
*						 ending, write and read pointers. 
* 
* Inputs		:	pMessageQueue - Specifies a handle to the message queue.
*
* Outputs		:	None
*
* Dependencies	:	hCurrentThread
*/

void InitializeCircularBuffer(RZK_MESSAGEQUEUE_t * pMessageQueue)
{
	/* Initialize the pResPrevious and pResNext pointers to point to it's own control block */
	pMessageQueue -> pLastPosition = pMessageQueue -> pResNext = ( RZK_TCB_t * ) NULL;

	/* Initialize the etWaitingQueue */
	pMessageQueue -> etWaitingQueue = MESSAGE_NONE;

	/* Initialize the start and end pointers of the queue */
	pMessageQueue -> pRead = pMessageQueue -> pWrite = pMessageQueue -> pStart ;

} /* end of InitializeCircularBuffer */