xdr_reference.c revision 92986 
1/*	$NetBSD: xdr_reference.c,v 1.13 2000/01/22 22:19:18 mycroft Exp	$ */
2
3/*
4 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
5 * unrestricted use provided that this legend is included on all tape
6 * media and as a part of the software program in whole or part.  Users
7 * may copy or modify Sun RPC without charge, but are not authorized
8 * to license or distribute it to anyone else except as part of a product or
9 * program developed by the user.
10 *
11 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
12 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
13 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
14 *
15 * Sun RPC is provided with no support and without any obligation on the
16 * part of Sun Microsystems, Inc. to assist in its use, correction,
17 * modification or enhancement.
18 *
19 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
20 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
21 * OR ANY PART THEREOF.
22 *
23 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
24 * or profits or other special, indirect and consequential damages, even if
25 * Sun has been advised of the possibility of such damages.
26 *
27 * Sun Microsystems, Inc.
28 * 2550 Garcia Avenue
29 * Mountain View, California  94043
30 */
31
32#include <sys/cdefs.h>
33#if defined(LIBC_SCCS) && !defined(lint)
34static char *sccsid = "@(#)xdr_reference.c 1.11 87/08/11 SMI";
35static char *sccsid = "@(#)xdr_reference.c	2.1 88/07/29 4.0 RPCSRC";
36static char *rcsid = "$FreeBSD: head/lib/libc/xdr/xdr_reference.c 92986 2002-03-22 21:53:29Z obrien $";
37#endif
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD: head/lib/libc/xdr/xdr_reference.c 92986 2002-03-22 21:53:29Z obrien $");
40
41/*
42 * xdr_reference.c, Generic XDR routines impelmentation.
43 *
44 * Copyright (C) 1987, Sun Microsystems, Inc.
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 "namespace.h"
51#include <err.h>
52#include <stdio.h>
53#include <stdlib.h>
54#include <string.h>
55
56#include <rpc/types.h>
57#include <rpc/xdr.h>
58#include "libc_private.h"
59
60/*
61 * XDR an indirect pointer
62 * xdr_reference is for recursively translating a structure that is
63 * referenced by a pointer inside the structure that is currently being
64 * translated.  pp references a pointer to storage. If *pp is null
65 * the  necessary storage is allocated.
66 * size is the sizeof the referneced structure.
67 * proc is the routine to handle the referenced structure.
68 */
69bool_t
70xdr_reference(xdrs, pp, size, proc)
71	XDR *xdrs;
72	caddr_t *pp;		/* the pointer to work on */
73	u_int size;		/* size of the object pointed to */
74	xdrproc_t proc;		/* xdr routine to handle the object */
75{
76	caddr_t loc = *pp;
77	bool_t stat;
78
79	if (loc == NULL)
80		switch (xdrs->x_op) {
81		case XDR_FREE:
82			return (TRUE);
83
84		case XDR_DECODE:
85			*pp = loc = (caddr_t) mem_alloc(size);
86			if (loc == NULL) {
87				warnx("xdr_reference: out of memory");
88				return (FALSE);
89			}
90			memset(loc, 0, size);
91			break;
92
93		case XDR_ENCODE:
94			break;
95		}
96
97	stat = (*proc)(xdrs, loc);
98
99	if (xdrs->x_op == XDR_FREE) {
100		mem_free(loc, size);
101		*pp = NULL;
102	}
103	return (stat);
104}
105
106
107/*
108 * xdr_pointer():
109 *
110 * XDR a pointer to a possibly recursive data structure. This
111 * differs with xdr_reference in that it can serialize/deserialiaze
112 * trees correctly.
113 *
114 *  What's sent is actually a union:
115 *
116 *  union object_pointer switch (boolean b) {
117 *  case TRUE: object_data data;
118 *  case FALSE: void nothing;
119 *  }
120 *
121 * > objpp: Pointer to the pointer to the object.
122 * > obj_size: size of the object.
123 * > xdr_obj: routine to XDR an object.
124 *
125 */
126bool_t
127xdr_pointer(xdrs,objpp,obj_size,xdr_obj)
128	XDR *xdrs;
129	char **objpp;
130	u_int obj_size;
131	xdrproc_t xdr_obj;
132{
133
134	bool_t more_data;
135
136	more_data = (*objpp != NULL);
137	if (! xdr_bool(xdrs,&more_data)) {
138		return (FALSE);
139	}
140	if (! more_data) {
141		*objpp = NULL;
142		return (TRUE);
143	}
144	return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
145}
146