xref: /netbsd-src/lib/libc/rpc/xdr_reference.c (revision 1f2744e6e4915c9da2a3f980279398c4cf7d5e6d)
1 /*	$NetBSD: xdr_reference.c,v 1.3 1995/02/25 03:02:08 cgd 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 *sccsid = "from: @(#)xdr_reference.c 1.11 87/08/11 SMI";*/
34 /*static char *sccsid = "from: @(#)xdr_reference.c	2.1 88/07/29 4.0 RPCSRC";*/
35 static char *rcsid = "$NetBSD: xdr_reference.c,v 1.3 1995/02/25 03:02:08 cgd Exp $";
36 #endif
37 
38 /*
39  * xdr_reference.c, Generic XDR routines impelmentation.
40  *
41  * Copyright (C) 1987, Sun Microsystems, Inc.
42  *
43  * These are the "non-trivial" xdr primitives used to serialize and de-serialize
44  * "pointers".  See xdr.h for more info on the interface to xdr.
45  */
46 
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <rpc/types.h>
50 #include <rpc/xdr.h>
51 
52 #define LASTUNSIGNED	((u_int)0-1)
53 
54 /*
55  * XDR an indirect pointer
56  * xdr_reference is for recursively translating a structure that is
57  * referenced by a pointer inside the structure that is currently being
58  * translated.  pp references a pointer to storage. If *pp is null
59  * the  necessary storage is allocated.
60  * size is the sizeof the referneced structure.
61  * proc is the routine to handle the referenced structure.
62  */
63 bool_t
64 xdr_reference(xdrs, pp, size, proc)
65 	register 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 	register caddr_t loc = *pp;
71 	register 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 				(void) fprintf(stderr,
82 				    "xdr_reference: out of memory\n");
83 				return (FALSE);
84 			}
85 			bzero(loc, (int)size);
86 			break;
87 	}
88 
89 	stat = (*proc)(xdrs, loc, LASTUNSIGNED);
90 
91 	if (xdrs->x_op == XDR_FREE) {
92 		mem_free(loc, size);
93 		*pp = NULL;
94 	}
95 	return (stat);
96 }
97 
98 
99 /*
100  * xdr_pointer():
101  *
102  * XDR a pointer to a possibly recursive data structure. This
103  * differs with xdr_reference in that it can serialize/deserialiaze
104  * trees correctly.
105  *
106  *  What's sent is actually a union:
107  *
108  *  union object_pointer switch (boolean b) {
109  *  case TRUE: object_data data;
110  *  case FALSE: void nothing;
111  *  }
112  *
113  * > objpp: Pointer to the pointer to the object.
114  * > obj_size: size of the object.
115  * > xdr_obj: routine to XDR an object.
116  *
117  */
118 bool_t
119 xdr_pointer(xdrs,objpp,obj_size,xdr_obj)
120 	register XDR *xdrs;
121 	char **objpp;
122 	u_int obj_size;
123 	xdrproc_t xdr_obj;
124 {
125 
126 	bool_t more_data;
127 
128 	more_data = (*objpp != NULL);
129 	if (! xdr_bool(xdrs,&more_data)) {
130 		return (FALSE);
131 	}
132 	if (! more_data) {
133 		*objpp = NULL;
134 		return (TRUE);
135 	}
136 	return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
137 }
138