xref: /freebsd/sys/xdr/xdr_sizeof.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
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 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/malloc.h>
42 
43 #include <rpc/types.h>
44 #include <rpc/xdr.h>
45 
46 /* ARGSUSED */
47 static bool_t
48 x_putlong(XDR *xdrs, const long *longp)
49 {
50 
51 	xdrs->x_handy += BYTES_PER_XDR_UNIT;
52 	return (TRUE);
53 }
54 
55 /* ARGSUSED */
56 static bool_t
57 x_putbytes(XDR *xdrs, const char *bp, u_int len)
58 {
59 
60 	xdrs->x_handy += len;
61 	return (TRUE);
62 }
63 
64 static u_int
65 x_getpostn(XDR *xdrs)
66 {
67 
68 	return (xdrs->x_handy);
69 }
70 
71 /* ARGSUSED */
72 static bool_t
73 x_setpostn(XDR *xdrs, u_int pos)
74 {
75 
76 	/* This is not allowed */
77 	return (FALSE);
78 }
79 
80 static int32_t *
81 x_inline(XDR *xdrs, u_int len)
82 {
83 
84 	if (len == 0) {
85 		return (NULL);
86 	}
87 	if (xdrs->x_op != XDR_ENCODE) {
88 		return (NULL);
89 	}
90 	if (len < (u_int)(uintptr_t)xdrs->x_base) {
91 		/* x_private was already allocated */
92 		xdrs->x_handy += len;
93 		return ((int32_t *) xdrs->x_private);
94 	} else {
95 		/* Free the earlier space and allocate new area */
96 		if (xdrs->x_private)
97 			free(xdrs->x_private, M_RPC);
98 		if ((xdrs->x_private = (caddr_t) malloc(len, M_RPC, M_WAITOK)) == NULL) {
99 			xdrs->x_base = 0;
100 			return (NULL);
101 		}
102 		xdrs->x_base = (caddr_t)(uintptr_t) len;
103 		xdrs->x_handy += len;
104 		return ((int32_t *) xdrs->x_private);
105 	}
106 }
107 
108 static int
109 harmless(void)
110 {
111 
112 	/* Always return FALSE/NULL, as the case may be */
113 	return (0);
114 }
115 
116 static void
117 x_destroy(XDR *xdrs)
118 {
119 
120 	xdrs->x_handy = 0;
121 	xdrs->x_base = 0;
122 	if (xdrs->x_private) {
123 		free(xdrs->x_private, M_RPC);
124 		xdrs->x_private = NULL;
125 	}
126 	return;
127 }
128 
129 unsigned long
130 xdr_sizeof(xdrproc_t func, void *data)
131 {
132 	XDR x;
133 	struct xdr_ops ops;
134 	bool_t stat;
135 	/* to stop ANSI-C compiler from complaining */
136 	typedef  bool_t (* dummyfunc1)(XDR *, long *);
137 	typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, u_int);
138 
139 	ops.x_putlong = x_putlong;
140 	ops.x_putbytes = x_putbytes;
141 	ops.x_inline = x_inline;
142 	ops.x_getpostn = x_getpostn;
143 	ops.x_setpostn = x_setpostn;
144 	ops.x_destroy = x_destroy;
145 
146 	/* the other harmless ones */
147 	ops.x_getlong =  (dummyfunc1) harmless;
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 = (caddr_t) NULL;
154 	x.x_base = (caddr_t) 0;
155 
156 	stat = func(&x, data);
157 	if (x.x_private)
158 		free(x.x_private, M_RPC);
159 	return (stat == TRUE ? (unsigned) x.x_handy: 0);
160 }
161