1/*
2 *  Copyright (c) 2008 Sun Microsystems, Inc.
3 *  Written by Ricardo Correia <Ricardo.M.Correia@Sun.COM>
4 *
5 *  This file is part of the SPL, Solaris Porting Layer.
6 *
7 *  The SPL is free software; you can redistribute it and/or modify it
8 *  under the terms of the GNU General Public License as published by the
9 *  Free Software Foundation; either version 2 of the License, or (at your
10 *  option) any later version.
11 *
12 *  The SPL is distributed in the hope that it will be useful, but WITHOUT
13 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15 *  for more details.
16 *
17 *  You should have received a copy of the GNU General Public License along
18 *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
19 */
20
21#ifndef _SPL_RPC_XDR_H
22#define	_SPL_RPC_XDR_H
23
24#include <sys/types.h>
25
26/*
27 * XDR enums and types.
28 */
29enum xdr_op {
30	XDR_ENCODE,
31	XDR_DECODE
32};
33
34struct xdr_ops;
35
36typedef struct {
37	const struct xdr_ops	*x_ops;
38	    /* Let caller know xdrmem_create() succeeds */
39	caddr_t		x_addr;	/* Current buffer addr */
40	caddr_t		x_addr_end;	/* End of the buffer */
41	enum xdr_op	x_op;	/* Stream direction */
42} XDR;
43
44typedef bool_t (*xdrproc_t)(XDR *xdrs, void *ptr);
45
46struct xdr_ops {
47	bool_t (*xdr_control)(XDR *, int, void *);
48
49	bool_t (*xdr_char)(XDR *, char *);
50	bool_t (*xdr_u_short)(XDR *, unsigned short *);
51	bool_t (*xdr_u_int)(XDR *, unsigned *);
52	bool_t (*xdr_u_longlong_t)(XDR *, u_longlong_t *);
53
54	bool_t (*xdr_opaque)(XDR *, caddr_t, const uint_t);
55	bool_t (*xdr_string)(XDR *, char **, const uint_t);
56	bool_t (*xdr_array)(XDR *, caddr_t *, uint_t *, const uint_t,
57	    const uint_t, const xdrproc_t);
58};
59
60/*
61 * XDR control operator.
62 */
63#define	XDR_GET_BYTES_AVAIL 1
64
65struct xdr_bytesrec {
66	bool_t xc_is_last_record;
67	size_t xc_num_avail;
68};
69
70/*
71 * XDR functions.
72 */
73void xdrmem_create(XDR *xdrs, const caddr_t addr, const uint_t size,
74    const enum xdr_op op);
75
76#define	xdr_control(xdrs, req, info) \
77	(xdrs)->x_ops->xdr_control((xdrs), (req), (info))
78
79/*
80 * For precaution, the following are defined as static inlines instead of macros
81 * to get some amount of type safety.
82 *
83 * Also, macros wouldn't work in the case where typecasting is done, because it
84 * must be possible to reference the functions' addresses by these names.
85 */
86static inline bool_t xdr_char(XDR *xdrs, char *cp)
87{
88	return (xdrs->x_ops->xdr_char(xdrs, cp));
89}
90
91static inline bool_t xdr_u_short(XDR *xdrs, unsigned short *usp)
92{
93	return (xdrs->x_ops->xdr_u_short(xdrs, usp));
94}
95
96static inline bool_t xdr_short(XDR *xdrs, short *sp)
97{
98	BUILD_BUG_ON(sizeof (short) != 2);
99	return (xdrs->x_ops->xdr_u_short(xdrs, (unsigned short *) sp));
100}
101
102static inline bool_t xdr_u_int(XDR *xdrs, unsigned *up)
103{
104	return (xdrs->x_ops->xdr_u_int(xdrs, up));
105}
106
107static inline bool_t xdr_int(XDR *xdrs, int *ip)
108{
109	BUILD_BUG_ON(sizeof (int) != 4);
110	return (xdrs->x_ops->xdr_u_int(xdrs, (unsigned *)ip));
111}
112
113static inline bool_t xdr_u_longlong_t(XDR *xdrs, u_longlong_t *ullp)
114{
115	return (xdrs->x_ops->xdr_u_longlong_t(xdrs, ullp));
116}
117
118static inline bool_t xdr_longlong_t(XDR *xdrs, longlong_t *llp)
119{
120	BUILD_BUG_ON(sizeof (longlong_t) != 8);
121	return (xdrs->x_ops->xdr_u_longlong_t(xdrs, (u_longlong_t *)llp));
122}
123
124/*
125 * Fixed-length opaque data.
126 */
127static inline bool_t xdr_opaque(XDR *xdrs, caddr_t cp, const uint_t cnt)
128{
129	return (xdrs->x_ops->xdr_opaque(xdrs, cp, cnt));
130}
131
132/*
133 * Variable-length string.
134 * The *sp buffer must have (maxsize + 1) bytes.
135 */
136static inline bool_t xdr_string(XDR *xdrs, char **sp, const uint_t maxsize)
137{
138	return (xdrs->x_ops->xdr_string(xdrs, sp, maxsize));
139}
140
141/*
142 * Variable-length arrays.
143 */
144static inline bool_t xdr_array(XDR *xdrs, caddr_t *arrp, uint_t *sizep,
145    const uint_t maxsize, const uint_t elsize, const xdrproc_t elproc)
146{
147	return xdrs->x_ops->xdr_array(xdrs, arrp, sizep, maxsize, elsize,
148	    elproc);
149}
150
151#endif /* SPL_RPC_XDR_H */
152