/*      $NetBSD: xdr_stdio.c,v 1.14 2000/01/22 22:19:19 mycroft Exp $   */

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2010, Oracle America, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials
 *       provided with the distribution.
 *     * Neither the name of the "Oracle America, Inc." nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * xdr_stdio.c, XDR implementation on standard i/o file.
 *
 * This set of routines implements a XDR on a stdio stream.
 * XDR_ENCODE serializes onto the stream, XDR_DECODE de-serializes
 * from the stream.
 */

#include "namespace.h"
#include <stdio.h>

#include <arpa/inet.h>
#include <rpc/types.h>
#include <rpc/xdr.h>
#include "un-namespace.h"

static void xdrstdio_destroy(XDR *);
static bool_t xdrstdio_getlong(XDR *, long *);
static bool_t xdrstdio_putlong(XDR *, const long *);
static bool_t xdrstdio_getbytes(XDR *, char *, u_int);
static bool_t xdrstdio_putbytes(XDR *, const char *, u_int);
static u_int xdrstdio_getpos(XDR *);
static bool_t xdrstdio_setpos(XDR *, u_int);
static int32_t *xdrstdio_inline(XDR *, u_int);

/*
 * Ops vector for stdio type XDR
 */
static const struct xdr_ops     xdrstdio_ops = {
        xdrstdio_getlong,       /* deseraialize a long int */
        xdrstdio_putlong,       /* seraialize a long int */
        xdrstdio_getbytes,      /* deserialize counted bytes */
        xdrstdio_putbytes,      /* serialize counted bytes */
        xdrstdio_getpos,        /* get offset in the stream */
        xdrstdio_setpos,        /* set offset in the stream */
        xdrstdio_inline,        /* prime stream for inline macros */
        xdrstdio_destroy        /* destroy stream */
};

/*
 * Initialize a stdio xdr stream.
 * Sets the xdr stream handle xdrs for use on the stream file.
 * Operation flag is set to op.
 */
void
xdrstdio_create(XDR *xdrs, FILE *file, enum xdr_op op)
{

        xdrs->x_op = op;
        xdrs->x_ops = &xdrstdio_ops;
        xdrs->x_private = file;
        xdrs->x_handy = 0;
        xdrs->x_base = 0;
}

/*
 * Destroy a stdio xdr stream.
 * Cleans up the xdr stream handle xdrs previously set up by xdrstdio_create.
 */
static void
xdrstdio_destroy(XDR *xdrs)
{
        (void)fflush((FILE *)xdrs->x_private);
                /* XXX: should we close the file ?? */
}

static bool_t
xdrstdio_getlong(XDR *xdrs, long *lp)
{
        u_int32_t temp;

        if (fread(&temp, sizeof(int32_t), 1, (FILE *)xdrs->x_private) != 1)
                return (FALSE);
        *lp = (long)ntohl(temp);
        return (TRUE);
}

static bool_t
xdrstdio_putlong(XDR *xdrs, const long *lp)
{
        int32_t mycopy = htonl((u_int32_t)*lp);

        if (fwrite(&mycopy, sizeof(int32_t), 1, (FILE *)xdrs->x_private) != 1)
                return (FALSE);
        return (TRUE);
}

static bool_t
xdrstdio_getbytes(XDR *xdrs, char *addr, u_int len)
{

        if ((len != 0) && (fread(addr, (size_t)len, 1, (FILE *)xdrs->x_private) != 1))
                return (FALSE);
        return (TRUE);
}

static bool_t
xdrstdio_putbytes(XDR *xdrs, const char *addr, u_int len)
{

        if ((len != 0) && (fwrite(addr, (size_t)len, 1,
            (FILE *)xdrs->x_private) != 1))
                return (FALSE);
        return (TRUE);
}

static u_int
xdrstdio_getpos(XDR *xdrs)
{

        return ((u_int) ftell((FILE *)xdrs->x_private));
}

static bool_t
xdrstdio_setpos(XDR *xdrs, u_int pos) 
{ 

        return ((fseek((FILE *)xdrs->x_private, (long)pos, 0) < 0) ?
                FALSE : TRUE);
}

/* ARGSUSED */
static int32_t *
xdrstdio_inline(XDR *xdrs, u_int len)
{

        /*
         * Must do some work to implement this: must insure
         * enough data in the underlying stdio buffer,
         * that the buffer is aligned so that we can indirect through a
         * long *, and stuff this pointer in xdrs->x_buf.  Doing
         * a fread or fwrite to a scratch buffer would defeat
         * most of the gains to be had here and require storage
         * management on this buffer, so we don't do this.
         */
        return (NULL);
}