1 /* $NetBSD: xdr_reference.c,v 1.13 2000/01/22 22:19:18 mycroft Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-3-Clause
5 *
6 * Copyright (c) 2010, Oracle America, Inc.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are
10 * met:
11 *
12 * * Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * * Redistributions in binary form must reproduce the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer in the documentation and/or other materials
17 * provided with the distribution.
18 * * Neither the name of the "Oracle America, Inc." nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
27 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
29 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
33 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 /*
37 * xdr_reference.c, Generic XDR routines implementation.
38 *
39 * These are the "non-trivial" xdr primitives used to serialize and de-serialize
40 * "pointers". See xdr.h for more info on the interface to xdr.
41 */
42
43 #include "namespace.h"
44 #include <err.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48
49 #include <rpc/types.h>
50 #include <rpc/xdr.h>
51 #include "libc_private.h"
52
53 /*
54 * XDR an indirect pointer
55 * xdr_reference is for recursively translating a structure that is
56 * referenced by a pointer inside the structure that is currently being
57 * translated. pp references a pointer to storage. If *pp is null
58 * the necessary storage is allocated.
59 * size is the sizeof the referenced structure.
60 * proc is the routine to handle the referenced structure.
61 */
62 bool_t
xdr_reference(XDR * xdrs,caddr_t * pp,u_int size,xdrproc_t proc)63 xdr_reference(XDR *xdrs, caddr_t *pp, u_int size, xdrproc_t proc)
64 /*
65 * XDR *xdrs;
66 * caddr_t *pp; // the pointer to work on
67 * u_int size; // size of the object pointed to
68 * xdrproc_t proc; // xdr routine to handle the object
69 */
70 {
71 caddr_t loc = *pp;
72 bool_t stat;
73
74 if (loc == NULL)
75 switch (xdrs->x_op) {
76 case XDR_FREE:
77 return (TRUE);
78
79 case XDR_DECODE:
80 *pp = loc = (caddr_t) mem_alloc(size);
81 if (loc == NULL) {
82 warnx("xdr_reference: out of memory");
83 return (FALSE);
84 }
85 memset(loc, 0, size);
86 break;
87
88 case XDR_ENCODE:
89 break;
90 }
91
92 stat = (*proc)(xdrs, loc);
93
94 if (xdrs->x_op == XDR_FREE) {
95 mem_free(loc, size);
96 *pp = NULL;
97 }
98 return (stat);
99 }
100
101
102 /*
103 * xdr_pointer():
104 *
105 * XDR a pointer to a possibly recursive data structure. This
106 * differs with xdr_reference in that it can serialize/deserialiaze
107 * trees correctly.
108 *
109 * What's sent is actually a union:
110 *
111 * union object_pointer switch (boolean b) {
112 * case TRUE: object_data data;
113 * case FALSE: void nothing;
114 * }
115 *
116 * > objpp: Pointer to the pointer to the object.
117 * > obj_size: size of the object.
118 * > xdr_obj: routine to XDR an object.
119 *
120 */
121 bool_t
xdr_pointer(XDR * xdrs,char ** objpp,u_int obj_size,xdrproc_t xdr_obj)122 xdr_pointer(XDR *xdrs, char **objpp, u_int obj_size, xdrproc_t xdr_obj)
123 {
124
125 bool_t more_data;
126
127 more_data = (*objpp != NULL);
128 if (! xdr_bool(xdrs,&more_data)) {
129 return (FALSE);
130 }
131 if (! more_data) {
132 *objpp = NULL;
133 return (TRUE);
134 }
135 return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
136 }
137