xref: /netbsd-src/lib/libc/rpc/xdr_sizeof.c (revision a536ee5124e62c9a0051a252f7833dc8f50f44c9)
1 /*
2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3  * unrestricted use provided that this legend is included on all tape
4  * media and as a part of the software program in whole or part.  Users
5  * may copy or modify Sun RPC without charge, but are not authorized
6  * to license or distribute it to anyone else except as part of a product or
7  * program developed by the user.
8  *
9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12  *
13  * Sun RPC is provided with no support and without any obligation on the
14  * part of Sun Microsystems, Inc. to assist in its use, correction,
15  * modification or enhancement.
16  *
17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19  * OR ANY PART THEREOF.
20  *
21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22  * or profits or other special, indirect and consequential damages, even if
23  * Sun has been advised of the possibility of such damages.
24  *
25  * Sun Microsystems, Inc.
26  * 2550 Garcia Avenue
27  * Mountain View, California  94043
28  */
29 /*
30  * xdr_sizeof.c
31  *
32  * Copyright 1990 Sun Microsystems, Inc.
33  *
34  * General purpose routine to see how much space something will use
35  * when serialized using XDR.
36  */
37 
38 #include <sys/cdefs.h>
39 #if 0
40 __FBSDID("$FreeBSD: src/lib/libc/xdr/xdr_sizeof.c,v 1.5.38.1 2010/12/21 17:10:29 kensmith Exp $");
41 #else
42 __RCSID("$NetBSD: xdr_sizeof.c,v 1.4 2012/03/20 17:14:50 matt Exp $");
43 #endif
44 
45 #include "namespace.h"
46 #include <rpc/types.h>
47 #include <rpc/xdr.h>
48 #include <sys/types.h>
49 #include <stdlib.h>
50 
51 #ifdef __weak_alias
52 __weak_alias(xdr_sizeof,_xdr_sizeof)
53 #endif
54 
55 static bool_t x_putlong(XDR *, const long *);
56 static bool_t x_putbytes(XDR *, const char *, u_int);
57 static u_int x_getpostn(XDR *);
58 static bool_t x_setpostn(XDR *, u_int);
59 static int32_t *x_inline(XDR *, u_int);
60 static int harmless(void);
61 static void x_destroy(XDR *);
62 
63 /* ARGSUSED */
64 static bool_t
65 x_putlong(XDR *xdrs, const long *longp)
66 {
67 	xdrs->x_handy += BYTES_PER_XDR_UNIT;
68 	return (TRUE);
69 }
70 
71 /* ARGSUSED */
72 static bool_t
73 x_putbytes(XDR *xdrs, const char *bp, u_int len)
74 {
75 	xdrs->x_handy += len;
76 	return (TRUE);
77 }
78 
79 static u_int
80 x_getpostn(XDR *xdrs)
81 {
82 	return (xdrs->x_handy);
83 }
84 
85 /* ARGSUSED */
86 static bool_t
87 x_setpostn(XDR *xdrs, u_int pos)
88 {
89 	/* This is not allowed */
90 	return (FALSE);
91 }
92 
93 static int32_t *
94 x_inline(XDR *xdrs, u_int len)
95 {
96 	if (len == 0) {
97 		return (NULL);
98 	}
99 	if (xdrs->x_op != XDR_ENCODE) {
100 		return (NULL);
101 	}
102 	if (len < (u_int)(uintptr_t)xdrs->x_base) {
103 		/* x_private was already allocated */
104 		xdrs->x_handy += len;
105 		return ((int32_t *) xdrs->x_private);
106 	} else {
107 		/* Free the earlier space and allocate new area */
108 		if (xdrs->x_private)
109 			free(xdrs->x_private);
110 		if ((xdrs->x_private = malloc(len)) == NULL) {
111 			xdrs->x_base = 0;
112 			return (NULL);
113 		}
114 		xdrs->x_base = (caddr_t)(uintptr_t)len;
115 		xdrs->x_handy += len;
116 		return ((int32_t *) xdrs->x_private);
117 	}
118 }
119 
120 static int
121 harmless(void)
122 {
123 	/* Always return FALSE/NULL, as the case may be */
124 	return (0);
125 }
126 
127 static void
128 x_destroy(XDR *xdrs)
129 {
130 	xdrs->x_handy = 0;
131 	xdrs->x_base = 0;
132 	if (xdrs->x_private) {
133 		free(xdrs->x_private);
134 		xdrs->x_private = NULL;
135 	}
136 	return;
137 }
138 
139 unsigned long
140 xdr_sizeof(xdrproc_t func, void *data)
141 {
142 	XDR x;
143 	struct xdr_ops ops;
144 	bool_t stat;
145 	/* to stop ANSI-C compiler from complaining */
146 	typedef  bool_t (* dummyfunc1)(XDR *, long *);
147 	typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, u_int);
148 
149 	ops.x_putlong = x_putlong;
150 	ops.x_putbytes = x_putbytes;
151 	ops.x_inline = x_inline;
152 	ops.x_getpostn = x_getpostn;
153 	ops.x_setpostn = x_setpostn;
154 	ops.x_destroy = x_destroy;
155 
156 	/* the other harmless ones */
157 	ops.x_getlong =  (dummyfunc1) harmless;
158 	ops.x_getbytes = (dummyfunc2) harmless;
159 
160 	x.x_op = XDR_ENCODE;
161 	x.x_ops = &ops;
162 	x.x_handy = 0;
163 	x.x_private = (caddr_t) NULL;
164 	x.x_base = (caddr_t) 0;
165 
166 	stat = func(&x, data);
167 	if (x.x_private)
168 		free(x.x_private);
169 	return (stat == TRUE ? (unsigned) x.x_handy: 0);
170 }
171