xref: /freebsd/include/rpc/xdr.h (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, MERCHANTABILITY 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  *	from: @(#)xdr.h 1.19 87/04/22 SMI
30  *	from: @(#)xdr.h	2.2 88/07/29 4.0 RPCSRC
31  *	$Id: xdr.h,v 1.10 1997/05/28 04:45:15 wpaul Exp $
32  */
33 
34 /*
35  * xdr.h, External Data Representation Serialization Routines.
36  *
37  * Copyright (C) 1984, Sun Microsystems, Inc.
38  */
39 
40 #ifndef _RPC_XDR_H
41 #define _RPC_XDR_H
42 #include <sys/cdefs.h>
43 
44 /*
45  * XDR provides a conventional way for converting between C data
46  * types and an external bit-string representation.  Library supplied
47  * routines provide for the conversion on built-in C data types.  These
48  * routines and utility routines defined here are used to help implement
49  * a type encode/decode routine for each user-defined type.
50  *
51  * Each data type provides a single procedure which takes two arguments:
52  *
53  *	bool_t
54  *	xdrproc(xdrs, argresp)
55  *		XDR *xdrs;
56  *		<type> *argresp;
57  *
58  * xdrs is an instance of a XDR handle, to which or from which the data
59  * type is to be converted.  argresp is a pointer to the structure to be
60  * converted.  The XDR handle contains an operation field which indicates
61  * which of the operations (ENCODE, DECODE * or FREE) is to be performed.
62  *
63  * XDR_DECODE may allocate space if the pointer argresp is null.  This
64  * data can be freed with the XDR_FREE operation.
65  *
66  * We write only one procedure per data type to make it easy
67  * to keep the encode and decode procedures for a data type consistent.
68  * In many cases the same code performs all operations on a user defined type,
69  * because all the hard work is done in the component type routines.
70  * decode as a series of calls on the nested data types.
71  */
72 
73 /*
74  * Xdr operations.  XDR_ENCODE causes the type to be encoded into the
75  * stream.  XDR_DECODE causes the type to be extracted from the stream.
76  * XDR_FREE can be used to release the space allocated by an XDR_DECODE
77  * request.
78  */
79 enum xdr_op {
80 	XDR_ENCODE=0,
81 	XDR_DECODE=1,
82 	XDR_FREE=2
83 };
84 
85 /*
86  * This is the number of bytes per unit of external data.
87  */
88 #define BYTES_PER_XDR_UNIT	(4)
89 #define RNDUP(x)  ((((x) + BYTES_PER_XDR_UNIT - 1) / BYTES_PER_XDR_UNIT) \
90 		    * BYTES_PER_XDR_UNIT)
91 
92 /*
93  * The XDR handle.
94  * Contains operation which is being applied to the stream,
95  * an operations vector for the particular implementation (e.g. see xdr_mem.c),
96  * and two private fields for the use of the particular implementation.
97  */
98 typedef struct __rpc_xdr {
99 	enum xdr_op	x_op;		/* operation; fast additional param */
100 	struct xdr_ops {
101 		/* get a long from underlying stream */
102 		bool_t	(*x_getlong) __P((struct __rpc_xdr *, long *));
103 		/* put a long to underlying stream */
104 		bool_t	(*x_putlong) __P((struct __rpc_xdr *, long *));
105 		/* get some bytes from underlying stream */
106 		bool_t	(*x_getbytes) __P((struct __rpc_xdr *, caddr_t, u_int));
107 		/* put some bytes to underlying stream */
108 		bool_t	(*x_putbytes) __P((struct __rpc_xdr *, caddr_t, u_int));
109 		/* returns bytes off from beginning */
110 		u_int	(*x_getpostn) __P((struct __rpc_xdr *));
111 		/* lets you reposition the stream */
112 		bool_t  (*x_setpostn) __P((struct __rpc_xdr *, u_int));
113 		/* buf quick ptr to buffered data */
114 		int32_t *(*x_inline) __P((struct __rpc_xdr *, u_int));
115 		/* free privates of this xdr_stream */
116 		void	(*x_destroy) __P((struct __rpc_xdr *));
117 	} *x_ops;
118 	caddr_t 	x_public;	/* users' data */
119 	caddr_t		x_private;	/* pointer to private data */
120 	caddr_t 	x_base;		/* private used for position info */
121 	int		x_handy;	/* extra private word */
122 } XDR;
123 
124 /*
125  * A xdrproc_t exists for each data type which is to be encoded or decoded.
126  *
127  * The second argument to the xdrproc_t is a pointer to an opaque pointer.
128  * The opaque pointer generally points to a structure of the data type
129  * to be decoded.  If this pointer is 0, then the type routines should
130  * allocate dynamic storage of the appropriate size and return it.
131  *
132  * XXX can't actually prototype it, because some take three args!!!
133  */
134 typedef	bool_t (*xdrproc_t) __P((/* XDR *, void *, u_int */));
135 
136 /*
137  * Operations defined on a XDR handle
138  *
139  * XDR		*xdrs;
140  * long		*longp;
141  * caddr_t	 addr;
142  * u_int	 len;
143  * u_int	 pos;
144  */
145 #define XDR_GETLONG(xdrs, longp)			\
146 	(*(xdrs)->x_ops->x_getlong)(xdrs, longp)
147 #define xdr_getlong(xdrs, longp)			\
148 	(*(xdrs)->x_ops->x_getlong)(xdrs, longp)
149 
150 #define XDR_PUTLONG(xdrs, longp)			\
151 	(*(xdrs)->x_ops->x_putlong)(xdrs, longp)
152 #define xdr_putlong(xdrs, longp)			\
153 	(*(xdrs)->x_ops->x_putlong)(xdrs, longp)
154 
155 #define XDR_GETBYTES(xdrs, addr, len)			\
156 	(*(xdrs)->x_ops->x_getbytes)(xdrs, addr, len)
157 #define xdr_getbytes(xdrs, addr, len)			\
158 	(*(xdrs)->x_ops->x_getbytes)(xdrs, addr, len)
159 
160 #define XDR_PUTBYTES(xdrs, addr, len)			\
161 	(*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)
162 #define xdr_putbytes(xdrs, addr, len)			\
163 	(*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)
164 
165 #define XDR_GETPOS(xdrs)				\
166 	(*(xdrs)->x_ops->x_getpostn)(xdrs)
167 #define xdr_getpos(xdrs)				\
168 	(*(xdrs)->x_ops->x_getpostn)(xdrs)
169 
170 #define XDR_SETPOS(xdrs, pos)				\
171 	(*(xdrs)->x_ops->x_setpostn)(xdrs, pos)
172 #define xdr_setpos(xdrs, pos)				\
173 	(*(xdrs)->x_ops->x_setpostn)(xdrs, pos)
174 
175 #define	XDR_INLINE(xdrs, len)				\
176 	(*(xdrs)->x_ops->x_inline)(xdrs, len)
177 #define	xdr_inline(xdrs, len)				\
178 	(*(xdrs)->x_ops->x_inline)(xdrs, len)
179 
180 #define	XDR_DESTROY(xdrs)				\
181 	if ((xdrs)->x_ops->x_destroy) 			\
182 		(*(xdrs)->x_ops->x_destroy)(xdrs)
183 #define	xdr_destroy(xdrs)				\
184 	if ((xdrs)->x_ops->x_destroy) 			\
185 		(*(xdrs)->x_ops->x_destroy)(xdrs)
186 
187 /*
188  * Support struct for discriminated unions.
189  * You create an array of xdrdiscrim structures, terminated with
190  * a entry with a null procedure pointer.  The xdr_union routine gets
191  * the discriminant value and then searches the array of structures
192  * for a matching value.  If a match is found the associated xdr routine
193  * is called to handle that part of the union.  If there is
194  * no match, then a default routine may be called.
195  * If there is no match and no default routine it is an error.
196  */
197 #define NULL_xdrproc_t ((xdrproc_t)0)
198 struct xdr_discrim {
199 	int	value;
200 	xdrproc_t proc;
201 };
202 
203 /*
204  * In-line routines for fast encode/decode of primitive data types.
205  * Caveat emptor: these use single memory cycles to get the
206  * data from the underlying buffer, and will fail to operate
207  * properly if the data is not aligned.  The standard way to use these
208  * is to say:
209  *	if ((buf = XDR_INLINE(xdrs, count)) == NULL)
210  *		return (FALSE);
211  *	<<< macro calls >>>
212  * where ``count'' is the number of bytes of data occupied
213  * by the primitive data types.
214  *
215  * N.B. and frozen for all time: each data type here uses 4 bytes
216  * of external representation.
217  */
218 #define IXDR_GET_LONG(buf)		((long)ntohl((u_long)*(buf)++))
219 #define IXDR_PUT_LONG(buf, v)		(*(buf)++ = (long)htonl((u_long)v))
220 
221 #define IXDR_GET_BOOL(buf)		((bool_t)IXDR_GET_LONG(buf))
222 #define IXDR_GET_ENUM(buf, t)		((t)IXDR_GET_LONG(buf))
223 #define IXDR_GET_U_LONG(buf)		((u_long)IXDR_GET_LONG(buf))
224 #define IXDR_GET_SHORT(buf)		((short)IXDR_GET_LONG(buf))
225 #define IXDR_GET_U_SHORT(buf)		((u_short)IXDR_GET_LONG(buf))
226 
227 #define IXDR_PUT_BOOL(buf, v)		IXDR_PUT_LONG((buf), ((long)(v)))
228 #define IXDR_PUT_ENUM(buf, v)		IXDR_PUT_LONG((buf), ((long)(v)))
229 #define IXDR_PUT_U_LONG(buf, v)		IXDR_PUT_LONG((buf), ((long)(v)))
230 #define IXDR_PUT_SHORT(buf, v)		IXDR_PUT_LONG((buf), ((long)(v)))
231 #define IXDR_PUT_U_SHORT(buf, v)	IXDR_PUT_LONG((buf), ((long)(v)))
232 
233 /*
234  * These are the "generic" xdr routines.
235  */
236 __BEGIN_DECLS
237 extern bool_t	xdr_void	__P((void));
238 extern bool_t	xdr_int		__P((XDR *, int *));
239 extern bool_t	xdr_u_int	__P((XDR *, u_int *));
240 extern bool_t	xdr_long	__P((XDR *, long *));
241 extern bool_t	xdr_u_long	__P((XDR *, u_long *));
242 extern bool_t	xdr_short	__P((XDR *, short *));
243 extern bool_t	xdr_u_short	__P((XDR *, u_short *));
244 extern bool_t	xdr_int16_t	__P((XDR *, int16_t *));
245 extern bool_t	xdr_u_int16_t	__P((XDR *, u_int16_t *));
246 extern bool_t	xdr_int32_t	__P((XDR *, int32_t *));
247 extern bool_t	xdr_u_int32_t	__P((XDR *, u_int32_t *));
248 extern bool_t	xdr_int64_t	__P((XDR *, int64_t *));
249 extern bool_t	xdr_u_int64_t	__P((XDR *, u_int64_t *));
250 extern bool_t	xdr_bool	__P((XDR *, bool_t *));
251 extern bool_t	xdr_enum	__P((XDR *, enum_t *));
252 extern bool_t	xdr_array	__P((XDR *, char **, u_int *, u_int, u_int, xdrproc_t));
253 extern bool_t	xdr_bytes	__P((XDR *, char **, u_int *, u_int));
254 extern bool_t	xdr_opaque	__P((XDR *, caddr_t, u_int));
255 extern bool_t	xdr_string	__P((XDR *, char **, u_int));
256 extern bool_t	xdr_union	__P((XDR *, enum_t *, char *, struct xdr_discrim *, xdrproc_t));
257 extern unsigned long	xdr_sizeof __P((xdrproc_t, void *));
258 extern bool_t	xdr_char	__P((XDR *, char *));
259 extern bool_t	xdr_u_char	__P((XDR *, u_char *));
260 extern bool_t	xdr_vector	__P((XDR *, char *, u_int, u_int, xdrproc_t));
261 extern bool_t	xdr_float	__P((XDR *, float *));
262 extern bool_t	xdr_double	__P((XDR *, double *));
263 extern bool_t	xdr_reference	__P((XDR *, caddr_t *, u_int, xdrproc_t));
264 extern bool_t	xdr_pointer	__P((XDR *, caddr_t *, u_int, xdrproc_t));
265 extern bool_t	xdr_wrapstring	__P((XDR *, char **));
266 extern void	xdr_free 	__P((xdrproc_t, char *));
267 __END_DECLS
268 
269 /*
270  * Common opaque bytes objects used by many rpc protocols;
271  * declared here due to commonality.
272  */
273 #define MAX_NETOBJ_SZ 1024
274 struct netobj {
275 	u_int	n_len;
276 	char	*n_bytes;
277 };
278 typedef struct netobj netobj;
279 extern bool_t   xdr_netobj __P((XDR *, struct netobj *));
280 
281 /*
282  * These are the public routines for the various implementations of
283  * xdr streams.
284  */
285 __BEGIN_DECLS
286 /* XDR using memory buffers */
287 extern void   xdrmem_create	__P((XDR *, char *, u_int, enum xdr_op));
288 
289 #ifdef _STDIO_H_
290 /* XDR using stdio library */
291 extern void   xdrstdio_create	__P((XDR *, FILE *, enum xdr_op));
292 #endif
293 
294 /* XDR pseudo records for tcp */
295 extern void   xdrrec_create	__P((XDR *, u_int, u_int, char *,
296 				int (*) __P((caddr_t, caddr_t, int)),
297 				int (*) __P((caddr_t, caddr_t, int))));
298 
299 /* make end of xdr record */
300 extern bool_t xdrrec_endofrecord __P((XDR *, int));
301 
302 /* move to beginning of next record */
303 extern bool_t xdrrec_skiprecord	__P((XDR *));
304 
305 /* true if no more input */
306 extern bool_t xdrrec_eof	__P((XDR *));
307 __END_DECLS
308 
309 #endif /* !_RPC_XDR_H */
310