xref: /freebsd/lib/libc/xdr/xdr_reference.c (revision 8fc257994d0ce2396196d7a06d50d20c8015f4b7)
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 #if defined(LIBC_SCCS) && !defined(lint)
33 static char *sccsid2 = "@(#)xdr_reference.c 1.11 87/08/11 SMI";
34 static char *sccsid = "@(#)xdr_reference.c	2.1 88/07/29 4.0 RPCSRC";
35 #endif
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38 
39 /*
40  * xdr_reference.c, Generic XDR routines impelmentation.
41  *
42  * Copyright (C) 1987, Sun Microsystems, Inc.
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