xref: /illumos-gate/usr/src/lib/libnsl/rpc/xdr_sizeof.c (revision a386cc11a86ecb60f5a48078d22c1500e2ad003e)
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 2006 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 "mt.h"
35 #include <rpc/types.h>
36 #include <rpc/xdr.h>
37 #include <sys/types.h>
38 #include <stdlib.h>
39 
40 /* ARGSUSED1 */
41 static bool_t
42 x_putlong(XDR *xdrs, long *ip)
43 {
44 	xdrs->x_handy += BYTES_PER_XDR_UNIT;
45 	return (TRUE);
46 }
47 
48 #if defined(_LP64)
49 /* ARGSUSED1 */
50 static bool_t
51 x_putint32_t(XDR *xdrs, int32_t *ip)
52 {
53 	xdrs->x_handy += BYTES_PER_XDR_UNIT;
54 	return (TRUE);
55 }
56 #endif
57 
58 /* ARGSUSED */
59 static bool_t
60 x_putbytes(XDR *xdrs, char *bp, int len)
61 {
62 	xdrs->x_handy += len;
63 	return (TRUE);
64 }
65 
66 static uint_t
67 x_getpostn(XDR *xdrs)
68 {
69 	return (xdrs->x_handy);
70 }
71 
72 /* ARGSUSED */
73 static bool_t
74 x_setpostn(XDR *xdrs, uint_t pos)
75 {
76 	/* This is not allowed */
77 	return (FALSE);
78 }
79 
80 static rpc_inline_t *
81 x_inline(XDR *xdrs, int len)
82 {
83 	if (len == 0)
84 		return (NULL);
85 	if (xdrs->x_op != XDR_ENCODE)
86 		return (NULL);
87 	if (len < (intptr_t)xdrs->x_base) {
88 		/* x_private was already allocated */
89 		xdrs->x_handy += len;
90 		/* LINTED pointer cast */
91 		return ((rpc_inline_t *)xdrs->x_private);
92 	}
93 	/* Free the earlier space and allocate new area */
94 	if (xdrs->x_private)
95 		free(xdrs->x_private);
96 	if ((xdrs->x_private = malloc(len)) == NULL) {
97 		xdrs->x_base = 0;
98 		return (NULL);
99 	}
100 	xdrs->x_base = (caddr_t)(intptr_t)len;
101 	xdrs->x_handy += len;
102 	/* LINTED pointer cast */
103 	return ((rpc_inline_t *)xdrs->x_private);
104 }
105 
106 static int
107 harmless(void)
108 {
109 	/* Always return FALSE/NULL, as the case may be */
110 	return (0);
111 }
112 
113 static void
114 x_destroy(XDR *xdrs)
115 {
116 	xdrs->x_handy = 0;
117 	xdrs->x_base = 0;
118 	if (xdrs->x_private) {
119 		free(xdrs->x_private);
120 		xdrs->x_private = NULL;
121 	}
122 }
123 
124 uint_t
125 xdr_sizeof(xdrproc_t func, void *data)
126 {
127 	XDR x;
128 	struct xdr_ops ops;
129 	bool_t stat;
130 	/* to stop ANSI-C compiler from complaining */
131 	typedef  bool_t (* dummyfunc1)(XDR *, long *);
132 	typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, int);
133 	typedef  bool_t (* dummyfunc3)(XDR *, int32_t *);
134 
135 	ops.x_putlong = x_putlong;
136 	ops.x_getlong =  (dummyfunc1) harmless;
137 	ops.x_putbytes = x_putbytes;
138 	ops.x_inline = x_inline;
139 	ops.x_getpostn = x_getpostn;
140 	ops.x_setpostn = x_setpostn;
141 	ops.x_destroy = x_destroy;
142 #if defined(_LP64)
143 	ops.x_getint32 = (dummyfunc3) harmless;
144 	ops.x_putint32 = x_putint32_t;
145 #endif
146 
147 	/* the other harmless ones */
148 	ops.x_getbytes = (dummyfunc2) harmless;
149 
150 	x.x_op = XDR_ENCODE;
151 	x.x_ops = &ops;
152 	x.x_handy = 0;
153 	x.x_private = NULL;
154 	x.x_base = NULL;
155 
156 	stat = func(&x, data);
157 	if (x.x_private)
158 		free(x.x_private);
159 	return (stat == TRUE ? (uint_t)x.x_handy : 0);
160 }
161