xref: /freebsd/lib/libc/xdr/xdr_sizeof.c (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
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 <rpc/types.h>
39 #include <rpc/xdr.h>
40 #include <sys/types.h>
41 #include <stdlib.h>
42 
43 /* ARGSUSED */
44 static bool_t
45 x_putlong(xdrs, longp)
46 	XDR *xdrs;
47 	long *longp;
48 {
49 	xdrs->x_handy += BYTES_PER_XDR_UNIT;
50 	return (TRUE);
51 }
52 
53 /* ARGSUSED */
54 static bool_t
55 x_putbytes(xdrs, bp, len)
56 	XDR *xdrs;
57 	char  *bp;
58 	int len;
59 {
60 	xdrs->x_handy += len;
61 	return (TRUE);
62 }
63 
64 static u_int
65 x_getpostn(xdrs)
66 	XDR *xdrs;
67 {
68 	return (xdrs->x_handy);
69 }
70 
71 /* ARGSUSED */
72 static bool_t
73 x_setpostn(xdrs, pos)
74 	XDR *xdrs;
75 	u_int pos;
76 {
77 	/* This is not allowed */
78 	return (FALSE);
79 }
80 
81 static int32_t *
82 x_inline(xdrs, len)
83 	XDR *xdrs;
84 	long len;
85 {
86 	if (len == 0) {
87 		return (NULL);
88 	}
89 	if (xdrs->x_op != XDR_ENCODE) {
90 		return (NULL);
91 	}
92 	if (len < (long) xdrs->x_base) {
93 		/* x_private was already allocated */
94 		xdrs->x_handy += len;
95 		return ((int32_t *) xdrs->x_private);
96 	} else {
97 		/* Free the earlier space and allocate new area */
98 		if (xdrs->x_private)
99 			free(xdrs->x_private);
100 		if ((xdrs->x_private = (caddr_t) malloc(len)) == NULL) {
101 			xdrs->x_base = 0;
102 			return (NULL);
103 		}
104 		xdrs->x_base = (caddr_t) len;
105 		xdrs->x_handy += len;
106 		return ((int32_t *) xdrs->x_private);
107 	}
108 }
109 
110 static int
111 harmless()
112 {
113 	/* Always return FALSE/NULL, as the case may be */
114 	return (0);
115 }
116 
117 static void
118 x_destroy(xdrs)
119 	XDR *xdrs;
120 {
121 	xdrs->x_handy = 0;
122 	xdrs->x_base = 0;
123 	if (xdrs->x_private) {
124 		free(xdrs->x_private);
125 		xdrs->x_private = NULL;
126 	}
127 	return;
128 }
129 
130 unsigned long
131 xdr_sizeof(func, data)
132 	xdrproc_t func;
133 	void *data;
134 {
135 	XDR x;
136 	struct xdr_ops ops;
137 	bool_t stat;
138 	/* to stop ANSI-C compiler from complaining */
139 	typedef  bool_t (* dummyfunc1)(XDR *, long *);
140 	typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, u_int);
141 
142 	ops.x_putlong = x_putlong;
143 	ops.x_putbytes = x_putbytes;
144 	ops.x_inline = x_inline;
145 	ops.x_getpostn = x_getpostn;
146 	ops.x_setpostn = x_setpostn;
147 	ops.x_destroy = x_destroy;
148 
149 	/* the other harmless ones */
150 	ops.x_getlong =  (dummyfunc1) harmless;
151 	ops.x_getbytes = (dummyfunc2) harmless;
152 
153 	x.x_op = XDR_ENCODE;
154 	x.x_ops = &ops;
155 	x.x_handy = 0;
156 	x.x_private = (caddr_t) NULL;
157 	x.x_base = (caddr_t) 0;
158 
159 	stat = func(&x, data);
160 	if (x.x_private)
161 		free(x.x_private);
162 	return (stat == TRUE ? (unsigned) x.x_handy: 0);
163 }
164