xref: /dragonfly/lib/libc/xdr/xdr_reference.c (revision f746689a)
1 /*
2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3  * unrestricted use provided that this legend is included on all tape
4  * media and as a part of the software program in whole or part.  Users
5  * may copy or modify Sun RPC without charge, but are not authorized
6  * to license or distribute it to anyone else except as part of a product or
7  * program developed by the user.
8  *
9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12  *
13  * Sun RPC is provided with no support and without any obligation on the
14  * part of Sun Microsystems, Inc. to assist in its use, correction,
15  * modification or enhancement.
16  *
17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19  * OR ANY PART THEREOF.
20  *
21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22  * or profits or other special, indirect and consequential damages, even if
23  * Sun has been advised of the possibility of such damages.
24  *
25  * Sun Microsystems, Inc.
26  * 2550 Garcia Avenue
27  * Mountain View, California  94043
28  *
29  * @(#)xdr_reference.c 1.11 87/08/11 SMI
30  * @(#)xdr_reference.c	2.1 88/07/29 4.0 RPCSRC
31  * $NetBSD: xdr_reference.c,v 1.13 2000/01/22 22:19:18 mycroft Exp $
32  * $FreeBSD: src/lib/libc/xdr/xdr_reference.c,v 1.12 2004/10/16 06:32:43 obrien Exp $
33  * $DragonFly: src/lib/libc/xdr/xdr_reference.c,v 1.4 2005/12/05 00:47:57 swildner Exp $
34  */
35 
36 /*
37  * xdr_reference.c, Generic XDR routines impelmentation.
38  *
39  * Copyright (C) 1987, Sun Microsystems, Inc.
40  *
41  * These are the "non-trivial" xdr primitives used to serialize and de-serialize
42  * "pointers".  See xdr.h for more info on the interface to xdr.
43  */
44 
45 #include "namespace.h"
46 #include <err.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 
51 #include <rpc/types.h>
52 #include <rpc/xdr.h>
53 #include "libc_private.h"
54 
55 /*
56  * XDR an indirect pointer
57  * xdr_reference is for recursively translating a structure that is
58  * referenced by a pointer inside the structure that is currently being
59  * translated.  pp references a pointer to storage. If *pp is null
60  * the  necessary storage is allocated.
61  * size is the sizeof the referneced structure.
62  * proc is the routine to handle the referenced structure.
63  *
64  * Parameters:
65  *     pp:	the pointer to work on
66  *     size:	size of the object pointed to
67  *     proc:	xdr routine to handle the object
68  */
69 bool_t
70 xdr_reference(XDR *xdrs, caddr_t *pp, u_int size, xdrproc_t proc)
71 {
72 	caddr_t loc = *pp;
73 	bool_t stat;
74 
75 	if (loc == NULL)
76 		switch (xdrs->x_op) {
77 		case XDR_FREE:
78 			return (TRUE);
79 
80 		case XDR_DECODE:
81 			*pp = loc = (caddr_t) mem_alloc(size);
82 			if (loc == NULL) {
83 				warnx("xdr_reference: out of memory");
84 				return (FALSE);
85 			}
86 			memset(loc, 0, size);
87 			break;
88 
89 		case XDR_ENCODE:
90 			break;
91 		}
92 
93 	stat = (*proc)(xdrs, loc);
94 
95 	if (xdrs->x_op == XDR_FREE) {
96 		mem_free(loc, size);
97 		*pp = NULL;
98 	}
99 	return (stat);
100 }
101 
102 
103 /*
104  * xdr_pointer():
105  *
106  * XDR a pointer to a possibly recursive data structure. This
107  * differs with xdr_reference in that it can serialize/deserialiaze
108  * trees correctly.
109  *
110  *  What's sent is actually a union:
111  *
112  *  union object_pointer switch (boolean b) {
113  *  case TRUE: object_data data;
114  *  case FALSE: void nothing;
115  *  }
116  *
117  * > objpp: Pointer to the pointer to the object.
118  * > obj_size: size of the object.
119  * > xdr_obj: routine to XDR an object.
120  *
121  */
122 bool_t
123 xdr_pointer(XDR *xdrs, char **objpp, u_int obj_size, xdrproc_t xdr_obj)
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