zfscs.c

来自「zilog的实时操作系统RZK,可以移植到多种处理器上」· C语言 代码 · 共 53 行

/*
 * File       : ZFSCs.c
 * Description: This file contains the implementation of computation of 
				checksum for file contents
 * Author     : Mahadev K C
 * Created on : 30-APR-2003
 *
 * 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 * This file contains unpublished confidential and proprietary information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 "glextern.h"

//Function: ComputeCheckSum
//Description: This function will compute the checksum for the given number of bytes
ZFS_CHECKSUM_t ComputeCheckSum( IN ZFS_CHECKSUM_t oldcs, UINT8 *buf, UINT bytes )
{
	while( bytes != 0 )
		{
		oldcs += *buf ;
		buf++ ;
		bytes--;
		}
	return oldcs ;
}


//Function: RemoveCheckSum
//Description: This function will remove the checksum for the given number of bytes
ZFS_CHECKSUM_t RemoveCheckSum( IN ZFS_CHECKSUM_t oldcs, UINT8 *buf, UINT bytes )
{
	while( bytes != 0 )
		{
		oldcs -= *buf ;
		buf++ ;
		bytes--;
		}
	return oldcs ;

}