xref: /freebsd/lib/libc/xdr/xdr_reference.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 #if defined(LIBC_SCCS) && !defined(lint)
37 static char *sccsid2 = "@(#)xdr_reference.c 1.11 87/08/11 SMI";
38 static char *sccsid = "@(#)xdr_reference.c	2.1 88/07/29 4.0 RPCSRC";
39 #endif
40 /*
41  * xdr_reference.c, Generic XDR routines implementation.
42  *
43  * These are the "non-trivial" xdr primitives used to serialize and de-serialize
44  * "pointers".  See xdr.h for more info on the interface to xdr.
45  */
46 
47 #include "namespace.h"
48 #include <err.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 
53 #include <rpc/types.h>
54 #include <rpc/xdr.h>
55 #include "libc_private.h"
56 
57 /*
58  * XDR an indirect pointer
59  * xdr_reference is for recursively translating a structure that is
60  * referenced by a pointer inside the structure that is currently being
61  * translated.  pp references a pointer to storage. If *pp is null
62  * the  necessary storage is allocated.
63  * size is the sizeof the referneced structure.
64  * proc is the routine to handle the referenced structure.
65  */
66 bool_t
67 xdr_reference(XDR *xdrs, caddr_t *pp, u_int size, xdrproc_t proc)
68 /*
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 {
75 	caddr_t loc = *pp;
76 	bool_t stat;
77 
78 	if (loc == NULL)
79 		switch (xdrs->x_op) {
80 		case XDR_FREE:
81 			return (TRUE);
82 
83 		case XDR_DECODE:
84 			*pp = loc = (caddr_t) mem_alloc(size);
85 			if (loc == NULL) {
86 				warnx("xdr_reference: out of memory");
87 				return (FALSE);
88 			}
89 			memset(loc, 0, size);
90 			break;
91 
92 		case XDR_ENCODE:
93 			break;
94 		}
95 
96 	stat = (*proc)(xdrs, loc);
97 
98 	if (xdrs->x_op == XDR_FREE) {
99 		mem_free(loc, size);
100 		*pp = NULL;
101 	}
102 	return (stat);
103 }
104 
105 
106 /*
107  * xdr_pointer():
108  *
109  * XDR a pointer to a possibly recursive data structure. This
110  * differs with xdr_reference in that it can serialize/deserialiaze
111  * trees correctly.
112  *
113  *  What's sent is actually a union:
114  *
115  *  union object_pointer switch (boolean b) {
116  *  case TRUE: object_data data;
117  *  case FALSE: void nothing;
118  *  }
119  *
120  * > objpp: Pointer to the pointer to the object.
121  * > obj_size: size of the object.
122  * > xdr_obj: routine to XDR an object.
123  *
124  */
125 bool_t
126 xdr_pointer(XDR *xdrs, char **objpp, u_int obj_size, xdrproc_t xdr_obj)
127 {
128 
129 	bool_t more_data;
130 
131 	more_data = (*objpp != NULL);
132 	if (! xdr_bool(xdrs,&more_data)) {
133 		return (FALSE);
134 	}
135 	if (! more_data) {
136 		*objpp = NULL;
137 		return (TRUE);
138 	}
139 	return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
140 }
141