xdr_reference.c revision 273188 
1/*	$NetBSD: xdr_reference.c,v 1.13 2000/01/22 22:19:18 mycroft Exp	$ */
2
3/*-
4 * Copyright (c) 2010, Oracle America, Inc.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met:
9 *
10 *     * Redistributions of source code must retain the above copyright
11 *       notice, this list of conditions and the following disclaimer.
12 *     * Redistributions in binary form must reproduce the above
13 *       copyright notice, this list of conditions and the following
14 *       disclaimer in the documentation and/or other materials
15 *       provided with the distribution.
16 *     * Neither the name of the "Oracle America, Inc." nor the names of its
17 *       contributors may be used to endorse or promote products derived
18 *       from this software without specific prior written permission.
19 *
20 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24 *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
25 *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27 *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30 *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#if defined(LIBC_SCCS) && !defined(lint)
35static char *sccsid2 = "@(#)xdr_reference.c 1.11 87/08/11 SMI";
36static char *sccsid = "@(#)xdr_reference.c	2.1 88/07/29 4.0 RPCSRC";
37#endif
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD: releng/10.1/lib/libc/xdr/xdr_reference.c 273188 2014-10-16 22:00:24Z hrs $");
40
41/*
42 * xdr_reference.c, Generic XDR routines impelmentation.
43 *
44 * These are the "non-trivial" xdr primitives used to serialize and de-serialize
45 * "pointers".  See xdr.h for more info on the interface to xdr.
46 */
47
48#include "namespace.h"
49#include <err.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <string.h>
53
54#include <rpc/types.h>
55#include <rpc/xdr.h>
56#include "libc_private.h"
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(xdrs, pp, size, proc)
69	XDR *xdrs;
70	caddr_t *pp;		/* the pointer to work on */
71	u_int size;		/* size of the object pointed to */
72	xdrproc_t proc;		/* xdr routine to handle the object */
73{
74	caddr_t loc = *pp;
75	bool_t stat;
76
77	if (loc == NULL)
78		switch (xdrs->x_op) {
79		case XDR_FREE:
80			return (TRUE);
81
82		case XDR_DECODE:
83			*pp = loc = (caddr_t) mem_alloc(size);
84			if (loc == NULL) {
85				warnx("xdr_reference: out of memory");
86				return (FALSE);
87			}
88			memset(loc, 0, size);
89			break;
90
91		case XDR_ENCODE:
92			break;
93		}
94
95	stat = (*proc)(xdrs, loc);
96
97	if (xdrs->x_op == XDR_FREE) {
98		mem_free(loc, size);
99		*pp = NULL;
100	}
101	return (stat);
102}
103
104
105/*
106 * xdr_pointer():
107 *
108 * XDR a pointer to a possibly recursive data structure. This
109 * differs with xdr_reference in that it can serialize/deserialiaze
110 * trees correctly.
111 *
112 *  What's sent is actually a union:
113 *
114 *  union object_pointer switch (boolean b) {
115 *  case TRUE: object_data data;
116 *  case FALSE: void nothing;
117 *  }
118 *
119 * > objpp: Pointer to the pointer to the object.
120 * > obj_size: size of the object.
121 * > xdr_obj: routine to XDR an object.
122 *
123 */
124bool_t
125xdr_pointer(xdrs,objpp,obj_size,xdr_obj)
126	XDR *xdrs;
127	char **objpp;
128	u_int obj_size;
129	xdrproc_t xdr_obj;
130{
131
132	bool_t more_data;
133
134	more_data = (*objpp != NULL);
135	if (! xdr_bool(xdrs,&more_data)) {
136		return (FALSE);
137	}
138	if (! more_data) {
139		*objpp = NULL;
140		return (TRUE);
141	}
142	return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
143}
144