libnsl/rpc/xdr_sizeof.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * General purpose routine to see how much space something will use
 * when serialized using XDR.
 */
#include "mt.h"
#include <rpc/types.h>
#include <rpc/xdr.h>
#include <sys/types.h>
#include <stdlib.h>

/* ARGSUSED1 */
static bool_t
x_putlong(XDR *xdrs, long *ip)
{
    xdrs->x_handy += BYTES_PER_XDR_UNIT;
    return (TRUE);
}

#if defined(_LP64)
/* ARGSUSED1 */
static bool_t
x_putint32_t(XDR *xdrs, int32_t *ip)
{
    xdrs->x_handy += BYTES_PER_XDR_UNIT;
    return (TRUE);
}
#endif

/* ARGSUSED */
static bool_t
x_putbytes(XDR *xdrs, char *bp, int len)
{
    xdrs->x_handy += len;
    return (TRUE);
}

static uint_t
x_getpostn(XDR *xdrs)
{
    return (xdrs->x_handy);
}

/* ARGSUSED */
static bool_t
x_setpostn(XDR *xdrs, uint_t pos)
{
    /* This is not allowed */
    return (FALSE);
}

static rpc_inline_t *
x_inline(XDR *xdrs, int len)
{
    if (len == 0)
        return (NULL);
    if (xdrs->x_op != XDR_ENCODE)
        return (NULL);
    if (len < (intptr_t)xdrs->x_base) {
        /* x_private was already allocated */
        xdrs->x_handy += len;
        /* LINTED pointer cast */
        return ((rpc_inline_t *)xdrs->x_private);
    }
    /* Free the earlier space and allocate new area */
    if (xdrs->x_private)
        free(xdrs->x_private);
    if ((xdrs->x_private = malloc(len)) == NULL) {
        xdrs->x_base = 0;
        return (NULL);
    }
    xdrs->x_base = (caddr_t)(intptr_t)len;
    xdrs->x_handy += len;
    /* LINTED pointer cast */
    return ((rpc_inline_t *)xdrs->x_private);
}

static int
harmless(void)
{
    /* Always return FALSE/NULL, as the case may be */
    return (0);
}

static void
x_destroy(XDR *xdrs)
{
    xdrs->x_handy = 0;
    xdrs->x_base = 0;
    if (xdrs->x_private) {
        free(xdrs->x_private);
        xdrs->x_private = NULL;
    }
}

uint_t
xdr_sizeof(xdrproc_t func, void *data)
{
    XDR x;
    struct xdr_ops ops;
    bool_t stat;
    /* to stop ANSI-C compiler from complaining */
    typedef  bool_t (* dummyfunc1)(XDR *, long *);
    typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, int);
    typedef  bool_t (* dummyfunc3)(XDR *, int32_t *);

    ops.x_putlong = x_putlong;
    ops.x_getlong =  (dummyfunc1) harmless;
    ops.x_putbytes = x_putbytes;
    ops.x_inline = x_inline;
    ops.x_getpostn = x_getpostn;
    ops.x_setpostn = x_setpostn;
    ops.x_destroy = x_destroy;
#if defined(_LP64)
    ops.x_getint32 = (dummyfunc3) harmless;
    ops.x_putint32 = x_putint32_t;
#endif

    /* the other harmless ones */
    ops.x_getbytes = (dummyfunc2) harmless;

    x.x_op = XDR_ENCODE;
    x.x_ops = &ops;
    x.x_handy = 0;
    x.x_private = NULL;
    x.x_base = NULL;

    stat = func(&x, data);
    if (x.x_private)
        free(x.x_private);
    return (stat == TRUE ? (uint_t)x.x_handy : 0);
}