xdr_array.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

#ifndef lint
static char *sccsid = "@(#)xdr_array.c	4.1      ULTRIX  7/3/90";
#endif lint

/************************************************************************
 *									*
 *			Copyright (c) 1986 by				*
 *		Digital Equipment Corporation, Maynard, MA		*
 *			All rights reserved.				*
 *									*
 *   This software is furnished under a license and may be used and	*
 *   copied  only  in accordance with the terms of such license and	*
 *   with the  inclusion  of  the  above  copyright  notice.   This	*
 *   software  or  any  other copies thereof may not be provided or	*
 *   otherwise made available to any other person.  No title to and	*
 *   ownership of the software is hereby transferred.			*
 *									*
 *   This software is  derived  from  software  received  from  the	*
 *   University    of   California,   Berkeley,   and   from   Bell	*
 *   Laboratories.  Use, duplication, or disclosure is  subject  to	*
 *   restrictions  under  license  agreements  with  University  of	*
 *   California and with AT&T.						*
 *									*
 *   The information in this software is subject to change  without	*
 *   notice  and should not be construed as a commitment by Digital	*
 *   Equipment Corporation.						*
 *									*
 *   Digital assumes no responsibility for the use  or  reliability	*
 *   of its software on equipment which is not supplied by Digital.	*
 *									*
 ************************************************************************/

/*
 *	Portions of this software have been licensed to 
 *	Digital Equipment Company, Maynard, MA.
 *	Copyright (c) 1986 Sun Microsystems, Inc.  ALL RIGHTS RESERVED.
 */
/*	Change Log
 *	04/13/89	jhw	picked up SUN 4.0 changes
 */

/*
 * xdr_array.c, Generic XDR routines impelmentation.
 *
 *
 * These are the "non-trivial" xdr primitives used to serialize and de-serialize
 * arrays.  See xdr.h for more info on the interface to xdr.
 */

#ifdef KERNEL
#include "../h/param.h"
#include "../h/systm.h"
#include "../rpc/types.h"
#include "../rpc/xdr.h"
#else
#include <rpc/types.h>
#include <rpc/xdr.h>
#include <stdio.h>
#endif
#define LASTUNSIGNED	((u_int)0-1)


/*
 * XDR an array of arbitrary elements
 * *addrp is a pointer to the array, *sizep is the number of elements.
 * If addrp is NULL (*sizep * elsize) bytes are allocated.
 * elsize is the size (in bytes) of each element, and elproc is the
 * xdr procedure to call to handle each element of the array.
 */
bool_t
xdr_array(xdrs, addrp, sizep, maxsize, elsize, elproc)
	register XDR *xdrs;
	caddr_t *addrp;		/* array pointer */
	u_int *sizep;		/* number of elements */
	u_int maxsize;		/* max numberof elements */
	u_int elsize;		/* size in bytes of each element */
	xdrproc_t elproc;	/* xdr routine to handle each element */
{
	register u_int i;
	register caddr_t target = *addrp;
	register u_int c;  /* the actual element count */
	register bool_t stat = TRUE;
	register int nodesize;

	/* like strings, arrays are really counted arrays */
	if (! xdr_u_int(xdrs, sizep)) {
#ifdef KERNEL
		printf("xdr_array: size FAILED\n");
#endif
		return (FALSE);
	}
	c = *sizep;
	if ((c > maxsize) && (xdrs->x_op != XDR_FREE)) {
#ifdef KERNEL
		printf("xdr_array: bad size FAILED\n");
#endif
		return (FALSE);
	}
	nodesize = c * elsize;

	/*
	 * if we are deserializing, we may need to allocate an array.
	 * We also save time by checking for a null array if we are freeing.
	 */
	if (target == NULL)
		switch (xdrs->x_op) {
		case XDR_DECODE:
			if (c == 0)
				return (TRUE);
			*addrp = target = (caddr_t)mem_alloc(0, 0, nodesize, 0);
#ifndef KERNEL
			if (target == NULL) {
				fprintf(stderr, "xdr_array: out of memory\n");
				return (FALSE);
			}
#endif
			bzero(target, (u_int)nodesize);
			break;

		case XDR_FREE:
			return (TRUE);
	}
	
	/*
	 * now we xdr each element of array
	 */
	for (i = 0; (i < c) && stat; i++) {
		stat = (*elproc)(xdrs, target, LASTUNSIGNED);
		target += elsize;
	}

	/*
	 * the array may need freeing
	 */
	if (xdrs->x_op == XDR_FREE) {
		mem_free(*addrp, nodesize);
		*addrp = NULL;
	}
	return (stat);
}
#ifndef KERNEL
/*
 * xdr_vector():
 *
 * XDR a fixed length array. Unlike variable-length arrays,
 * the storage of fixed length arrays is static and unfreeable.
 * > basep: base of the array
 * > size: size of the array
 * > elemsize: size of each element
 * > xdr_elem: routine to XDR each element
 */
bool_t
xdr_vector(xdrs, basep, nelem, elemsize, xdr_elem)
        register XDR *xdrs;
        register char *basep;
        register u_int nelem;
        register u_int elemsize;
        register xdrproc_t xdr_elem;
{
        register u_int i;
        register char *elptr;

        elptr = basep;
        for (i = 0; i < nelem; i++) {
                if (! (*xdr_elem)(xdrs, elptr, LASTUNSIGNED)) {
                        return(FALSE);
                }
                elptr += elemsize;
       }
        return(TRUE);
}
#endif /* !KERNEL */