xref: /illumos-gate/usr/src/uts/common/rpc/xdr_sizeof.c (revision 4c273cfa4ad8398f4157cd1d6fa54fc1cbc266ff)
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  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 /*
27  * Copyright 2012 Nexenta Systems, Inc. All rights reserved.
28  */
29 
30 #include <rpc/types.h>
31 #include <rpc/xdr.h>
32 #include <sys/types.h>
33 
34 /* ARGSUSED */
35 static bool_t
36 x_putint32_t(XDR *xdrs, int32_t *ip)
37 {
38 	xdrs->x_handy += BYTES_PER_XDR_UNIT;
39 	return (TRUE);
40 }
41 
42 /* ARGSUSED */
43 static bool_t
44 x_putbytes(XDR *xdrs, char *bp, int len)
45 {
46 	xdrs->x_handy += len;
47 	return (TRUE);
48 }
49 
50 static uint_t
51 x_getpostn(XDR *xdrs)
52 {
53 	return (xdrs->x_handy);
54 }
55 
56 /* ARGSUSED */
57 static bool_t
58 x_setpostn(XDR *xdrs, uint_t pos)
59 {
60 	/* This is not allowed */
61 	return (FALSE);
62 }
63 
64 static rpc_inline_t *
65 x_inline(XDR *xdrs, int len)
66 {
67 	if (len == 0) {
68 		return (NULL);
69 	}
70 	if (xdrs->x_op != XDR_ENCODE) {
71 		return (NULL);
72 	}
73 	if (len < (uintptr_t)xdrs->x_base) {
74 		/* x_private was already allocated */
75 		xdrs->x_handy += len;
76 		return ((rpc_inline_t *)xdrs->x_private);
77 	} else {
78 		/* Free the earlier space and allocate new area */
79 		if (xdrs->x_private)
80 			mem_free(xdrs->x_private, (uintptr_t)xdrs->x_base);
81 		if ((xdrs->x_private = (caddr_t)mem_alloc(len)) == NULL) {
82 			xdrs->x_base = 0;
83 			return (NULL);
84 		}
85 		xdrs->x_base = (caddr_t)(uintptr_t)len;
86 		xdrs->x_handy += len;
87 		return ((rpc_inline_t *)xdrs->x_private);
88 	}
89 }
90 
91 static int
92 harmless()
93 {
94 	/* Always return FALSE/NULL, as the case may be */
95 	return (0);
96 }
97 
98 static void
99 x_destroy(XDR *xdrs)
100 {
101 	xdrs->x_handy = 0;
102 	if (xdrs->x_private) {
103 		mem_free(xdrs->x_private, (uintptr_t)xdrs->x_base);
104 		xdrs->x_private = NULL;
105 	}
106 	xdrs->x_base = 0;
107 }
108 
109 unsigned int
110 xdr_sizeof(xdrproc_t func, void *data)
111 {
112 	XDR x;
113 	struct xdr_ops ops;
114 	bool_t stat;
115 	/* to stop ANSI-C compiler from complaining */
116 	typedef  bool_t (* dummyfunc1)(XDR *, long *);
117 	typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, int);
118 	typedef  bool_t (* dummyfunc3)(XDR *, int32_t *);
119 	typedef	 bool_t (* dummyfunc4)(XDR *, int, void *);
120 
121 	ops.x_putbytes = x_putbytes;
122 	ops.x_inline = x_inline;
123 	ops.x_getpostn = x_getpostn;
124 	ops.x_setpostn = x_setpostn;
125 	ops.x_destroy = x_destroy;
126 
127 #if defined(_LP64) || defined(_KERNEL)
128 	ops.x_getint32 = (dummyfunc3)harmless;
129 	ops.x_putint32 = x_putint32_t;
130 #endif
131 
132 	/* the other harmless ones */
133 	ops.x_getbytes = (dummyfunc2)harmless;
134 	ops.x_control = (dummyfunc4)harmless;
135 
136 	x.x_op = XDR_ENCODE;
137 	x.x_ops = &ops;
138 	x.x_handy = 0;
139 	x.x_private = (caddr_t)NULL;
140 	x.x_base = NULL;
141 
142 	stat = func(&x, data);
143 	if (x.x_private)
144 		mem_free(x.x_private, (uintptr_t)x.x_base);
145 	return (stat == TRUE ? (unsigned int)x.x_handy: 0);
146 }
147