1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
28/*	  All Rights Reserved  	*/
29
30/*
31 * Portions of this source code were derived from Berkeley 4.3 BSD
32 * under license from the Regents of the University of California.
33 */
34
35#pragma ident	"%Z%%M%	%I%	%E% SMI"
36
37/*
38 * #if !defined(lint) && defined(SCCSIDS)
39 * static char sccsid[] = "@(#)xdr_refer.c 1.21 89/02/28 SMI";
40 * #endif
41 */
42
43/*
44 * xdr_refer.c, Generic XDR routines impelmentation.
45 *
46 * These are the "non-trivial" xdr primitives used to serialize and de-serialize
47 * "pointers".  See xdr.h for more info on the interface to xdr.
48 */
49
50#include <sys/param.h>
51#include <sys/systm.h>
52
53#include <rpc/types.h>
54#include <rpc/xdr.h>
55
56#define	LASTUNSIGNED	((uint_t)0-1)
57
58/*
59 * XDR an indirect pointer
60 * xdr_reference is for recursively translating a structure that is
61 * referenced by a pointer inside the structure that is currently being
62 * translated.  pp references a pointer to storage. If *pp is null
63 * the  necessary storage is allocated.
64 * size is the sizeof the referneced structure.
65 * proc is the routine to handle the referenced structure.
66 */
67bool_t
68xdr_reference(XDR *xdrs, caddr_t *pp, uint_t size, const xdrproc_t proc)
69{
70	caddr_t loc = *pp;
71	bool_t stat;
72
73	if (loc == NULL) {
74		switch (xdrs->x_op) {
75		case XDR_FREE:
76			return (TRUE);
77
78		case XDR_DECODE:
79			*pp = loc = (caddr_t)mem_alloc(size);
80			bzero(loc, size);
81			break;
82
83		case XDR_ENCODE:
84			break;
85		}
86	}
87
88	stat = (*proc)(xdrs, loc, LASTUNSIGNED);
89
90	if (xdrs->x_op == XDR_FREE) {
91		mem_free(loc, size);
92		*pp = NULL;
93	}
94	return (stat);
95}
96
97/*
98 * xdr_pointer():
99 *
100 * XDR a pointer to a possibly recursive data structure. This
101 * differs with xdr_reference in that it can serialize/deserialiaze
102 * trees correctly.
103 *
104 *  What's sent is actually a union:
105 *
106 *  union object_pointer switch (boolean b) {
107 *  case TRUE: object_data data;
108 *  case FALSE: void nothing;
109 *  }
110 *
111 * > objpp: Pointer to the pointer to the object.
112 * > obj_size: size of the object.
113 * > xdr_obj: routine to XDR an object.
114 *
115 */
116bool_t
117xdr_pointer(XDR *xdrs, char **objpp, uint_t obj_size, const xdrproc_t xdr_obj)
118{
119	bool_t more_data;
120
121	more_data = (*objpp != NULL);
122	if (!xdr_bool(xdrs, &more_data))
123		return (FALSE);
124	if (!more_data) {
125		*objpp = NULL;
126		return (TRUE);
127	}
128	return (xdr_reference(xdrs, objpp, obj_size, xdr_obj));
129}
130