/*      $NetBSD: xdr_reference.c,v 1.19 2022/02/13 22:20:08 andvar Exp $        */

/*
* 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.
*/

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char *sccsid = "@(#)xdr_reference.c 1.11 87/08/11 SMI";
static char *sccsid = "@(#)xdr_reference.c      2.1 88/07/29 4.0 RPCSRC";
#else
__RCSID("$NetBSD: xdr_reference.c,v 1.19 2022/02/13 22:20:08 andvar Exp $");
#endif
#endif

/*
* xdr_reference.c, Generic XDR routines implementation.
*
* Copyright (C) 1987, Sun Microsystems, Inc.
*
* These are the "non-trivial" xdr primitives used to serialize and de-serialize
* "pointers".  See xdr.h for more info on the interface to xdr.
*/

#include "namespace.h"

#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <rpc/types.h>
#include <rpc/xdr.h>

#ifdef __weak_alias
__weak_alias(xdr_pointer,_xdr_pointer)
__weak_alias(xdr_reference,_xdr_reference)
#endif

/*
* XDR an indirect pointer
* xdr_reference is for recursively translating a structure that is
* referenced by a pointer inside the structure that is currently being
* translated.  pp references a pointer to storage. If *pp is null
* the  necessary storage is allocated.
* size is the sizeof the referenced structure.
* proc is the routine to handle the referenced structure.
*/
bool_t
xdr_reference(XDR *xdrs, caddr_t *pp, u_int size, xdrproc_t proc)
{
       caddr_t loc = *pp;
       bool_t stat;

       if (loc == NULL)
               switch (xdrs->x_op) {
               case XDR_FREE:
                       return (TRUE);

               case XDR_DECODE:
                       *pp = loc = mem_alloc(size);
                       if (loc == NULL) {
                               warn("%s: out of memory", __func__);
                               return (FALSE);
                       }
                       memset(loc, 0, size);
                       break;

               case XDR_ENCODE:
                       break;
               }

       stat = (*proc)(xdrs, loc);

       if (xdrs->x_op == XDR_FREE) {
               mem_free(loc, size);
               *pp = NULL;
       }
       return (stat);
}


/*
* xdr_pointer():
*
* XDR a pointer to a possibly recursive data structure. This
* differs with xdr_reference in that it can serialize/deserialize
* trees correctly.
*
*  What's sent is actually a union:
*
*  union object_pointer switch (boolean b) {
*  case TRUE: object_data data;
*  case FALSE: void nothing;
*  }
*
* > objpp: Pointer to the pointer to the object.
* > obj_size: size of the object.
* > xdr_obj: routine to XDR an object.
*
*/
bool_t
xdr_pointer(XDR *xdrs, char **objpp, u_int obj_size, xdrproc_t xdr_obj)
{

       bool_t more_data;

       more_data = (*objpp != NULL);
       if (! xdr_bool(xdrs,&more_data)) {
               return (FALSE);
       }
       if (! more_data) {
               *objpp = NULL;
               return (TRUE);
       }
       return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
}