xref: /titanic_41/usr/src/uts/common/rpc/xdr_refer.c (revision 749f21d359d8fbd020c974a1a5227316221bfc9c)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * Portions of this source code were derived from Berkeley 4.3 BSD
32  * under license from the Regents of the University of California.
33  */
34 
35 #pragma ident	"%Z%%M%	%I%	%E% SMI"
36 
37 /*
38  * #if !defined(lint) && defined(SCCSIDS)
39  * static char sccsid[] = "@(#)xdr_refer.c 1.21 89/02/28 SMI";
40  * #endif
41  */
42 
43 /*
44  * xdr_refer.c, Generic XDR routines impelmentation.
45  *
46  * These are the "non-trivial" xdr primitives used to serialize and de-serialize
47  * "pointers".  See xdr.h for more info on the interface to xdr.
48  */
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 
53 #include <rpc/types.h>
54 #include <rpc/xdr.h>
55 
56 #define	LASTUNSIGNED	((uint_t)0-1)
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(XDR *xdrs, caddr_t *pp, uint_t size, const xdrproc_t proc)
69 {
70 	caddr_t loc = *pp;
71 	bool_t stat;
72 
73 	if (loc == NULL) {
74 		switch (xdrs->x_op) {
75 		case XDR_FREE:
76 			return (TRUE);
77 
78 		case XDR_DECODE:
79 			*pp = loc = (caddr_t)mem_alloc(size);
80 			bzero(loc, size);
81 			break;
82 
83 		case XDR_ENCODE:
84 			break;
85 		}
86 	}
87 
88 	stat = (*proc)(xdrs, loc, LASTUNSIGNED);
89 
90 	if (xdrs->x_op == XDR_FREE) {
91 		mem_free(loc, size);
92 		*pp = NULL;
93 	}
94 	return (stat);
95 }
96 
97 /*
98  * xdr_pointer():
99  *
100  * XDR a pointer to a possibly recursive data structure. This
101  * differs with xdr_reference in that it can serialize/deserialiaze
102  * trees correctly.
103  *
104  *  What's sent is actually a union:
105  *
106  *  union object_pointer switch (boolean b) {
107  *  case TRUE: object_data data;
108  *  case FALSE: void nothing;
109  *  }
110  *
111  * > objpp: Pointer to the pointer to the object.
112  * > obj_size: size of the object.
113  * > xdr_obj: routine to XDR an object.
114  *
115  */
116 bool_t
117 xdr_pointer(XDR *xdrs, char **objpp, uint_t obj_size, const xdrproc_t xdr_obj)
118 {
119 	bool_t more_data;
120 
121 	more_data = (*objpp != NULL);
122 	if (!xdr_bool(xdrs, &more_data))
123 		return (FALSE);
124 	if (!more_data) {
125 		*objpp = NULL;
126 		return (TRUE);
127 	}
128 	return (xdr_reference(xdrs, objpp, obj_size, xdr_obj));
129 }
130