xref: /freebsd/lib/libc/xdr/xdr_reference.c (revision 57718be8fa0bd5edc11ab9a72e68cc71982939a6)
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)
35 static char *sccsid2 = "@(#)xdr_reference.c 1.11 87/08/11 SMI";
36 static char *sccsid = "@(#)xdr_reference.c	2.1 88/07/29 4.0 RPCSRC";
37 #endif
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
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  */
67 bool_t
68 xdr_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  */
124 bool_t
125 xdr_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