xref: /freebsd/sys/xdr/xdr_reference.c (revision ebacd8013fe5f7fdf9f6a5b286f6680dd2891036)
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 implementation.
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 <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/malloc.h>
51 
52 #include <rpc/types.h>
53 #include <rpc/xdr.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 bool_t
65 xdr_reference(XDR *xdrs,
66     caddr_t *pp,		/* the pointer to work on */
67     u_int size,			/* size of the object pointed to */
68     xdrproc_t proc)		/* xdr routine to handle the object */
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 			if (loc == NULL) {
81 				printf("xdr_reference: out of memory");
82 				return (FALSE);
83 			}
84 			memset(loc, 0, size);
85 			break;
86 
87 		case XDR_ENCODE:
88 			break;
89 		}
90 
91 	stat = (*proc)(xdrs, loc);
92 
93 	if (xdrs->x_op == XDR_FREE) {
94 		mem_free(loc, size);
95 		*pp = NULL;
96 	}
97 	return (stat);
98 }
99 
100 /*
101  * xdr_pointer():
102  *
103  * XDR a pointer to a possibly recursive data structure. This
104  * differs with xdr_reference in that it can serialize/deserialiaze
105  * trees correctly.
106  *
107  *  What's sent is actually a union:
108  *
109  *  union object_pointer switch (boolean b) {
110  *  case TRUE: object_data data;
111  *  case FALSE: void nothing;
112  *  }
113  *
114  * > objpp: Pointer to the pointer to the object.
115  * > obj_size: size of the object.
116  * > xdr_obj: routine to XDR an object.
117  *
118  */
119 bool_t
120 xdr_pointer(XDR *xdrs, char **objpp, u_int obj_size, xdrproc_t xdr_obj)
121 {
122 
123 	bool_t more_data;
124 
125 	more_data = (*objpp != NULL);
126 	if (! xdr_bool(xdrs,&more_data)) {
127 		return (FALSE);
128 	}
129 	if (! more_data) {
130 		*objpp = NULL;
131 		return (TRUE);
132 	}
133 	return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
134 }
135