xref: /illumos-gate/usr/src/lib/libnsl/rpc/xdr_sizeof.c (revision 16ade92d9ce9c9ab33a25f7a2fdd00b581b6efda)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 
23 /*
24  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 
28 #pragma ident	"%Z%%M%	%I%	%E% SMI"
29 
30 /*
31  * General purpose routine to see how much space something will use
32  * when serialized using XDR.
33  */
34 #include <rpc/types.h>
35 #include <rpc/xdr.h>
36 #include <sys/types.h>
37 #include <stdlib.h>
38 
39 /* ARGSUSED1 */
40 static bool_t
41 x_putlong(XDR *xdrs, long *ip)
42 {
43 	xdrs->x_handy += BYTES_PER_XDR_UNIT;
44 	return (TRUE);
45 }
46 
47 #if defined(_LP64)
48 /* ARGSUSED1 */
49 static bool_t
50 x_putint32_t(XDR *xdrs, int32_t *ip)
51 {
52 	xdrs->x_handy += BYTES_PER_XDR_UNIT;
53 	return (TRUE);
54 }
55 #endif
56 
57 /* ARGSUSED */
58 static bool_t
59 x_putbytes(XDR *xdrs, char *bp, int len)
60 {
61 	xdrs->x_handy += len;
62 	return (TRUE);
63 }
64 
65 static uint_t
66 x_getpostn(XDR *xdrs)
67 {
68 	return (xdrs->x_handy);
69 }
70 
71 /* ARGSUSED */
72 static bool_t
73 x_setpostn(XDR *xdrs, uint_t pos)
74 {
75 	/* This is not allowed */
76 	return (FALSE);
77 }
78 
79 static rpc_inline_t *
80 x_inline(XDR *xdrs, int len)
81 {
82 	if (len == 0)
83 		return (NULL);
84 	if (xdrs->x_op != XDR_ENCODE)
85 		return (NULL);
86 	if (len < (intptr_t)xdrs->x_base) {
87 		/* x_private was already allocated */
88 		xdrs->x_handy += len;
89 		/* LINTED pointer cast */
90 		return ((rpc_inline_t *)xdrs->x_private);
91 	}
92 	/* Free the earlier space and allocate new area */
93 	if (xdrs->x_private)
94 		free(xdrs->x_private);
95 	if ((xdrs->x_private = malloc(len)) == NULL) {
96 		xdrs->x_base = 0;
97 		return (NULL);
98 	}
99 	xdrs->x_base = (caddr_t)(intptr_t)len;
100 	xdrs->x_handy += len;
101 	/* LINTED pointer cast */
102 	return ((rpc_inline_t *)xdrs->x_private);
103 }
104 
105 static int
106 harmless(void)
107 {
108 	/* Always return FALSE/NULL, as the case may be */
109 	return (0);
110 }
111 
112 static void
113 x_destroy(XDR *xdrs)
114 {
115 	xdrs->x_handy = 0;
116 	xdrs->x_base = 0;
117 	if (xdrs->x_private) {
118 		free(xdrs->x_private);
119 		xdrs->x_private = NULL;
120 	}
121 }
122 
123 uint_t
124 xdr_sizeof(xdrproc_t func, void *data)
125 {
126 	XDR x;
127 	struct xdr_ops ops;
128 	bool_t stat;
129 	/* to stop ANSI-C compiler from complaining */
130 	typedef  bool_t (* dummyfunc1)(XDR *, long *);
131 	typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, int);
132 	typedef  bool_t (* dummyfunc3)(XDR *, int32_t *);
133 
134 	ops.x_putlong = x_putlong;
135 	ops.x_getlong =  (dummyfunc1) harmless;
136 	ops.x_putbytes = x_putbytes;
137 	ops.x_inline = x_inline;
138 	ops.x_getpostn = x_getpostn;
139 	ops.x_setpostn = x_setpostn;
140 	ops.x_destroy = x_destroy;
141 #if defined(_LP64)
142 	ops.x_getint32 = (dummyfunc3) harmless;
143 	ops.x_putint32 = x_putint32_t;
144 #endif
145 
146 	/* the other harmless ones */
147 	ops.x_getbytes = (dummyfunc2) harmless;
148 
149 	x.x_op = XDR_ENCODE;
150 	x.x_ops = &ops;
151 	x.x_handy = 0;
152 	x.x_private = NULL;
153 	x.x_base = NULL;
154 
155 	stat = func(&x, data);
156 	if (x.x_private)
157 		free(x.x_private);
158 	return (stat == TRUE ? (uint_t)x.x_handy : 0);
159 }
160