1 /* $OpenBSD: xdr_reference.c,v 1.13 2022/12/27 17:10:06 jmc 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 /*
35 * xdr_reference.c, Generic XDR routines implementation.
36 *
37 * These are the "non-trivial" xdr primitives used to serialize and de-serialize
38 * "pointers". See xdr.h for more info on the interface to xdr.
39 */
40
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <rpc/types.h>
45 #include <rpc/xdr.h>
46
47 /*
48 * XDR an indirect pointer
49 * xdr_reference is for recursively translating a structure that is
50 * referenced by a pointer inside the structure that is currently being
51 * translated. pp references a pointer to storage. If *pp is null
52 * the necessary storage is allocated.
53 * size is the sizeof the referenced structure.
54 * proc is the routine to handle the referenced structure.
55 */
56 bool_t
xdr_reference(XDR * xdrs,caddr_t * pp,u_int size,xdrproc_t proc)57 xdr_reference(XDR *xdrs,
58 caddr_t *pp, /* the pointer to work on */
59 u_int size, /* size of the object pointed to */
60 xdrproc_t proc) /* xdr routine to handle the object */
61 {
62 caddr_t loc = *pp;
63 bool_t stat;
64
65 if (loc == NULL)
66 switch (xdrs->x_op) {
67 case XDR_FREE:
68 return (TRUE);
69
70 case XDR_DECODE:
71 *pp = loc = (caddr_t) calloc(size, 1);
72 if (loc == NULL)
73 return (FALSE);
74 break;
75 default:
76 break;
77 }
78
79 stat = (*proc)(xdrs, loc);
80
81 if (xdrs->x_op == XDR_FREE) {
82 mem_free(loc, size);
83 *pp = NULL;
84 }
85 return (stat);
86 }
87 DEF_WEAK(xdr_reference);
88
89
90 /*
91 * xdr_pointer():
92 *
93 * XDR a pointer to a possibly recursive data structure. This
94 * differs with xdr_reference in that it can serialize/deserialiaze
95 * trees correctly.
96 *
97 * What's sent is actually a union:
98 *
99 * union object_pointer switch (boolean b) {
100 * case TRUE: object_data data;
101 * case FALSE: void nothing;
102 * }
103 *
104 * > objpp: Pointer to the pointer to the object.
105 * > obj_size: size of the object.
106 * > xdr_obj: routine to XDR an object.
107 *
108 */
109 bool_t
xdr_pointer(XDR * xdrs,char ** objpp,u_int obj_size,xdrproc_t xdr_obj)110 xdr_pointer(XDR *xdrs, char **objpp, u_int obj_size, xdrproc_t xdr_obj)
111 {
112
113 bool_t more_data;
114
115 more_data = (*objpp != NULL);
116 if (! xdr_bool(xdrs,&more_data)) {
117 return (FALSE);
118 }
119 if (! more_data) {
120 *objpp = NULL;
121 return (TRUE);
122 }
123 return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
124 }
125 DEF_WEAK(xdr_pointer);
126