include/rpc/xdr.h

   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  * $FreeBSD: src/include/rpc/xdr.h,v 1.14.2.1 2003/03/20 12:59:55 jedgar Exp $
  32  * $DragonFly: src/include/rpc/xdr.h,v 1.3 2003/11/14 01:01:50 dillon Exp $
  33  */
  34
  35 /*
  36  * xdr.h, External Data Representation Serialization Routines.
  37  *
  38  * Copyright (C) 1984, Sun Microsystems, Inc.
  39  */
  40
  41 #ifndef _RPC_XDR_H
  42 #define _RPC_XDR_H
  43 #include <sys/cdefs.h>
  44
  45 /*
  46  * XDR provides a conventional way for converting between C data
  47  * types and an external bit-string representation.  Library supplied
  48  * routines provide for the conversion on built-in C data types.  These
  49  * routines and utility routines defined here are used to help implement
  50  * a type encode/decode routine for each user-defined type.
  51  *
  52  * Each data type provides a single procedure which takes two arguments:
  53  *
  54  *      bool_t
  55  *      xdrproc(xdrs, argresp)
  56  *              XDR *xdrs;
  57  *              <type> *argresp;
  58  *
  59  * xdrs is an instance of a XDR handle, to which or from which the data
  60  * type is to be converted.  argresp is a pointer to the structure to be
  61  * converted.  The XDR handle contains an operation field which indicates
  62  * which of the operations (ENCODE, DECODE * or FREE) is to be performed.
  63  *
  64  * XDR_DECODE may allocate space if the pointer argresp is null.  This
  65  * data can be freed with the XDR_FREE operation.
  66  *
  67  * We write only one procedure per data type to make it easy
  68  * to keep the encode and decode procedures for a data type consistent.
  69  * In many cases the same code performs all operations on a user defined type,
  70  * because all the hard work is done in the component type routines.
  71  * decode as a series of calls on the nested data types.
  72  */
  73
  74 /*
  75  * Xdr operations.  XDR_ENCODE causes the type to be encoded into the
  76  * stream.  XDR_DECODE causes the type to be extracted from the stream.
  77  * XDR_FREE can be used to release the space allocated by an XDR_DECODE
  78  * request.
  79  */
  80 enum xdr_op {
  81         XDR_ENCODE=0,
  82         XDR_DECODE=1,
  83         XDR_FREE=2
  84 };
  85
  86 /*
  87  * This is the number of bytes per unit of external data.
  88  */
  89 #define BYTES_PER_XDR_UNIT      (4)
  90 #define RNDUP(x)  ((((x) + BYTES_PER_XDR_UNIT - 1) / BYTES_PER_XDR_UNIT) \
  91                     * BYTES_PER_XDR_UNIT)
  92
  93 /*
  94  * The XDR handle.
  95  * Contains operation which is being applied to the stream,
  96  * an operations vector for the particular implementation (e.g. see xdr_mem.c),
  97  * and two private fields for the use of the particular implementation.
  98  */
  99 typedef struct __rpc_xdr {
 100         enum xdr_op     x_op;           /* operation; fast additional param */
 101         struct xdr_ops {
 102                 /* get a long from underlying stream */
 103                 bool_t  (*x_getlong) (struct __rpc_xdr *, long *);
 104                 /* put a long to underlying stream */
 105                 bool_t  (*x_putlong) (struct __rpc_xdr *, long *);
 106                 /* get some bytes from underlying stream */
 107                 bool_t  (*x_getbytes) (struct __rpc_xdr *, caddr_t, u_int);
 108                 /* put some bytes to underlying stream */
 109                 bool_t  (*x_putbytes) (struct __rpc_xdr *, caddr_t, u_int);
 110                 /* returns bytes off from beginning */
 111                 u_int   (*x_getpostn) (struct __rpc_xdr *);
 112                 /* lets you reposition the stream */
 113                 bool_t  (*x_setpostn) (struct __rpc_xdr *, u_int);
 114                 /* buf quick ptr to buffered data */
 115                 int32_t *(*x_inline) (struct __rpc_xdr *, u_int);
 116                 /* free privates of this xdr_stream */
 117                 void    (*x_destroy) (struct __rpc_xdr *);
 118         } *x_ops;
 119         caddr_t         x_public;       /* users' data */
 120         caddr_t         x_private;      /* pointer to private data */
 121         caddr_t         x_base;         /* private used for position info */
 122         u_int           x_handy;        /* extra private word */
 123 } XDR;
 124
 125 /*
 126  * A xdrproc_t exists for each data type which is to be encoded or decoded.
 127  *
 128  * The second argument to the xdrproc_t is a pointer to an opaque pointer.
 129  * The opaque pointer generally points to a structure of the data type
 130  * to be decoded.  If this pointer is 0, then the type routines should
 131  * allocate dynamic storage of the appropriate size and return it.
 132  */
 133 #ifdef _KERNEL
 134 typedef bool_t (*xdrproc_t) (XDR *, void *, u_int);
 135 #else
 136 /*
 137  * XXX can't actually prototype it, because some take two args!!!
 138  */
 139 typedef bool_t (*xdrproc_t) (/* XDR *, void *, u_int */);
 140 #endif
 141
 142 /*
 143  * Operations defined on a XDR handle
 144  *
 145  * XDR          *xdrs;
 146  * long         *longp;
 147  * caddr_t       addr;
 148  * u_int         len;
 149  * u_int         pos;
 150  */
 151 #define XDR_GETLONG(xdrs, longp)                        \
 152         (*(xdrs)->x_ops->x_getlong)(xdrs, longp)
 153 #define xdr_getlong(xdrs, longp)                        \
 154         (*(xdrs)->x_ops->x_getlong)(xdrs, longp)
 155
 156 #define XDR_PUTLONG(xdrs, longp)                        \
 157         (*(xdrs)->x_ops->x_putlong)(xdrs, longp)
 158 #define xdr_putlong(xdrs, longp)                        \
 159         (*(xdrs)->x_ops->x_putlong)(xdrs, longp)
 160
 161 #define XDR_GETBYTES(xdrs, addr, len)                   \
 162         (*(xdrs)->x_ops->x_getbytes)(xdrs, addr, len)
 163 #define xdr_getbytes(xdrs, addr, len)                   \
 164         (*(xdrs)->x_ops->x_getbytes)(xdrs, addr, len)
 165
 166 #define XDR_PUTBYTES(xdrs, addr, len)                   \
 167         (*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)
 168 #define xdr_putbytes(xdrs, addr, len)                   \
 169         (*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)
 170
 171 #define XDR_GETPOS(xdrs)                                \
 172         (*(xdrs)->x_ops->x_getpostn)(xdrs)
 173 #define xdr_getpos(xdrs)                                \
 174         (*(xdrs)->x_ops->x_getpostn)(xdrs)
 175
 176 #define XDR_SETPOS(xdrs, pos)                           \
 177         (*(xdrs)->x_ops->x_setpostn)(xdrs, pos)
 178 #define xdr_setpos(xdrs, pos)                           \
 179         (*(xdrs)->x_ops->x_setpostn)(xdrs, pos)
 180
 181 #define XDR_INLINE(xdrs, len)                           \
 182         (*(xdrs)->x_ops->x_inline)(xdrs, len)
 183 #define xdr_inline(xdrs, len)                           \
 184         (*(xdrs)->x_ops->x_inline)(xdrs, len)
 185
 186 #define XDR_DESTROY(xdrs)                               \
 187         if ((xdrs)->x_ops->x_destroy)                   \
 188                 (*(xdrs)->x_ops->x_destroy)(xdrs)
 189 #define xdr_destroy(xdrs)                               \
 190         if ((xdrs)->x_ops->x_destroy)                   \
 191                 (*(xdrs)->x_ops->x_destroy)(xdrs)
 192
 193 /*
 194  * Support struct for discriminated unions.
 195  * You create an array of xdrdiscrim structures, terminated with
 196  * a entry with a null procedure pointer.  The xdr_union routine gets
 197  * the discriminant value and then searches the array of structures
 198  * for a matching value.  If a match is found the associated xdr routine
 199  * is called to handle that part of the union.  If there is
 200  * no match, then a default routine may be called.
 201  * If there is no match and no default routine it is an error.
 202  */
 203 #define NULL_xdrproc_t ((xdrproc_t)0)
 204 struct xdr_discrim {
 205         int     value;
 206         xdrproc_t proc;
 207 };
 208
 209 /*
 210  * In-line routines for fast encode/decode of primitive data types.
 211  * Caveat emptor: these use single memory cycles to get the
 212  * data from the underlying buffer, and will fail to operate
 213  * properly if the data is not aligned.  The standard way to use these
 214  * is to say:
 215  *      if ((buf = XDR_INLINE(xdrs, count)) == NULL)
 216  *              return (FALSE);
 217  *      <<< macro calls >>>
 218  * where ``count'' is the number of bytes of data occupied
 219  * by the primitive data types.
 220  *
 221  * N.B. and frozen for all time: each data type here uses 4 bytes
 222  * of external representation.
 223  */
 224 #define IXDR_GET_LONG(buf)              ((long)ntohl((u_long)*(buf)++))
 225 #define IXDR_PUT_LONG(buf, v)           (*(buf)++ = (long)htonl((u_long)v))
 226
 227 #define IXDR_GET_BOOL(buf)              ((bool_t)IXDR_GET_LONG(buf))
 228 #define IXDR_GET_ENUM(buf, t)           ((t)IXDR_GET_LONG(buf))
 229 #define IXDR_GET_U_LONG(buf)            ((u_long)IXDR_GET_LONG(buf))
 230 #define IXDR_GET_SHORT(buf)             ((short)IXDR_GET_LONG(buf))
 231 #define IXDR_GET_U_SHORT(buf)           ((u_short)IXDR_GET_LONG(buf))
 232
 233 #define IXDR_PUT_BOOL(buf, v)           IXDR_PUT_LONG((buf), ((long)(v)))
 234 #define IXDR_PUT_ENUM(buf, v)           IXDR_PUT_LONG((buf), ((long)(v)))
 235 #define IXDR_PUT_U_LONG(buf, v)         IXDR_PUT_LONG((buf), ((long)(v)))
 236 #define IXDR_PUT_SHORT(buf, v)          IXDR_PUT_LONG((buf), ((long)(v)))
 237 #define IXDR_PUT_U_SHORT(buf, v)        IXDR_PUT_LONG((buf), ((long)(v)))
 238
 239 /*
 240  * These are the "generic" xdr routines.
 241  */
 242 __BEGIN_DECLS
 243 extern bool_t   xdr_void        (void);
 244 extern bool_t   xdr_int         (XDR *, int *);
 245 extern bool_t   xdr_u_int       (XDR *, u_int *);
 246 extern bool_t   xdr_long        (XDR *, long *);
 247 extern bool_t   xdr_u_long      (XDR *, u_long *);
 248 extern bool_t   xdr_short       (XDR *, short *);
 249 extern bool_t   xdr_u_short     (XDR *, u_short *);
 250 extern bool_t   xdr_int16_t     (XDR *, int16_t *);
 251 extern bool_t   xdr_u_int16_t   (XDR *, u_int16_t *);
 252 extern bool_t   xdr_int32_t     (XDR *, int32_t *);
 253 extern bool_t   xdr_u_int32_t   (XDR *, u_int32_t *);
 254 extern bool_t   xdr_int64_t     (XDR *, int64_t *);
 255 extern bool_t   xdr_u_int64_t   (XDR *, u_int64_t *);
 256 extern bool_t   xdr_bool        (XDR *, bool_t *);
 257 extern bool_t   xdr_enum        (XDR *, enum_t *);
 258 extern bool_t   xdr_array       (XDR *, char **, u_int *, u_int, u_int, xdrproc_t);
 259 extern bool_t   xdr_bytes       (XDR *, char **, u_int *, u_int);
 260 extern bool_t   xdr_opaque      (XDR *, caddr_t, u_int);
 261 extern bool_t   xdr_string      (XDR *, char **, u_int);
 262 extern bool_t   xdr_union       (XDR *, enum_t *, char *, struct xdr_discrim *, xdrproc_t);
 263 extern unsigned long    xdr_sizeof (xdrproc_t, void *);
 264 extern bool_t   xdr_char        (XDR *, char *);
 265 extern bool_t   xdr_u_char      (XDR *, u_char *);
 266 extern bool_t   xdr_vector      (XDR *, char *, u_int, u_int, xdrproc_t);
 267 extern bool_t   xdr_float       (XDR *, float *);
 268 extern bool_t   xdr_double      (XDR *, double *);
 269 extern bool_t   xdr_reference   (XDR *, caddr_t *, u_int, xdrproc_t);
 270 extern bool_t   xdr_pointer     (XDR *, caddr_t *, u_int, xdrproc_t);
 271 extern bool_t   xdr_wrapstring  (XDR *, char **);
 272 extern void     xdr_free        (xdrproc_t, char *);
 273 __END_DECLS
 274
 275 /*
 276  * Common opaque bytes objects used by many rpc protocols;
 277  * declared here due to commonality.
 278  */
 279 #define MAX_NETOBJ_SZ 1024
 280 struct netobj {
 281         u_int   n_len;
 282         char    *n_bytes;
 283 };
 284 typedef struct netobj netobj;
 285 extern bool_t   xdr_netobj (XDR *, struct netobj *);
 286
 287 /*
 288  * These are the public routines for the various implementations of
 289  * xdr streams.
 290  */
 291 __BEGIN_DECLS
 292 /* XDR using memory buffers */
 293 extern void   xdrmem_create     (XDR *, char *, u_int, enum xdr_op);
 294
 295 #ifdef _STDIO_H_
 296 /* XDR using stdio library */
 297 extern void   xdrstdio_create   (XDR *, FILE *, enum xdr_op);
 298 #endif
 299
 300 /* XDR pseudo records for tcp */
 301 extern void   xdrrec_create     (XDR *, u_int, u_int, char *,
 302                                 int (*) (caddr_t, caddr_t, int),
 303                                 int (*) (caddr_t, caddr_t, int));
 304
 305 /* make end of xdr record */
 306 extern bool_t xdrrec_endofrecord (XDR *, int);
 307
 308 /* move to beginning of next record */
 309 extern bool_t xdrrec_skiprecord (XDR *);
 310
 311 /* true if no more input */
 312 extern bool_t xdrrec_eof        (XDR *);
 313 __END_DECLS
 314
 315 #endif /* !_RPC_XDR_H */