sunrpc/rpc/xdr.h

   1 /* @(#)xdr.h    2.2 88/07/29 4.0 RPCSRC */
   2 /*
   3  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   4  * unrestricted use provided that this legend is included on all tape
   5  * media and as a part of the software program in whole or part.  Users
   6  * may copy or modify Sun RPC without charge, but are not authorized
   7  * to license or distribute it to anyone else except as part of a product or
   8  * program developed by the user.
   9  *
  10  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  11  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  12  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  13  *
  14  * Sun RPC is provided with no support and without any obligation on the
  15  * part of Sun Microsystems, Inc. to assist in its use, correction,
  16  * modification or enhancement.
  17  *
  18  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  19  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  20  * OR ANY PART THEREOF.
  21  *
  22  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  23  * or profits or other special, indirect and consequential damages, even if
  24  * Sun has been advised of the possibility of such damages.
  25  *
  26  * Sun Microsystems, Inc.
  27  * 2550 Garcia Avenue
  28  * Mountain View, California  94043
  29  */
  30 /*      @(#)xdr.h 1.19 87/04/22 SMI      */
  31
  32 /*
  33  * xdr.h, External Data Representation Serialization Routines.
  34  *
  35  * Copyright (C) 1984, Sun Microsystems, Inc.
  36  */
  37
  38 #ifndef _RPC_XDR_H
  39 #define _RPC_XDR_H 1
  40
  41 #include <features.h>
  42 #include <sys/types.h>
  43 #include <rpc/types.h>
  44
  45 /* We need FILE.  */
  46 #include <stdio.h>
  47
  48 __BEGIN_DECLS
  49
  50 /*
  51  * XDR provides a conventional way for converting between C data
  52  * types and an external bit-string representation.  Library supplied
  53  * routines provide for the conversion on built-in C data types.  These
  54  * routines and utility routines defined here are used to help implement
  55  * a type encode/decode routine for each user-defined type.
  56  *
  57  * Each data type provides a single procedure which takes two arguments:
  58  *
  59  *      bool_t
  60  *      xdrproc(xdrs, argresp)
  61  *              XDR *xdrs;
  62  *              <type> *argresp;
  63  *
  64  * xdrs is an instance of a XDR handle, to which or from which the data
  65  * type is to be converted.  argresp is a pointer to the structure to be
  66  * converted.  The XDR handle contains an operation field which indicates
  67  * which of the operations (ENCODE, DECODE * or FREE) is to be performed.
  68  *
  69  * XDR_DECODE may allocate space if the pointer argresp is null.  This
  70  * data can be freed with the XDR_FREE operation.
  71  *
  72  * We write only one procedure per data type to make it easy
  73  * to keep the encode and decode procedures for a data type consistent.
  74  * In many cases the same code performs all operations on a user defined type,
  75  * because all the hard work is done in the component type routines.
  76  * decode as a series of calls on the nested data types.
  77  */
  78
  79 /*
  80  * Xdr operations.  XDR_ENCODE causes the type to be encoded into the
  81  * stream.  XDR_DECODE causes the type to be extracted from the stream.
  82  * XDR_FREE can be used to release the space allocated by an XDR_DECODE
  83  * request.
  84  */
  85 enum xdr_op
  86   {
  87     XDR_ENCODE = 0,
  88     XDR_DECODE = 1,
  89     XDR_FREE = 2
  90   };
  91
  92 /*
  93  * This is the number of bytes per unit of external data.
  94  */
  95 #define BYTES_PER_XDR_UNIT      (4)
  96 /*
  97  * This only works if the above is a power of 2.  But it's defined to be
  98  * 4 by the appropriate RFCs.  So it will work.  And it's normally quicker
  99  * than the old routine.
 100  */
 101 #if 1
 102 #define RNDUP(x)  (((x) + BYTES_PER_XDR_UNIT - 1) & ~(BYTES_PER_XDR_UNIT - 1))
 103 #else /* this is the old routine */
 104 #define RNDUP(x)  ((((x) + BYTES_PER_XDR_UNIT - 1) / BYTES_PER_XDR_UNIT) \
 105                     * BYTES_PER_XDR_UNIT)
 106 #endif
 107
 108 /*
 109  * The XDR handle.
 110  * Contains operation which is being applied to the stream,
 111  * an operations vector for the particular implementation (e.g. see xdr_mem.c),
 112  * and two private fields for the use of the particular implementation.
 113  */
 114 typedef struct XDR XDR;
 115 struct XDR
 116   {
 117     enum xdr_op x_op;           /* operation; fast additional param */
 118     struct xdr_ops
 119       {
 120         bool_t (*x_getlong) __PMT ((XDR *__xdrs, long *__lp));
 121         /* get a long from underlying stream */
 122         bool_t (*x_putlong) __PMT ((XDR *__xdrs, __const long *__lp));
 123         /* put a long to " */
 124         bool_t (*x_getbytes) __PMT ((XDR *__xdrs, caddr_t __addr,
 125                                      u_int __len));
 126         /* get some bytes from " */
 127         bool_t (*x_putbytes) __PMT ((XDR *__xdrs, __const char *__addr,
 128                                      u_int __len));
 129         /* put some bytes to " */
 130         u_int (*x_getpostn) __PMT ((__const XDR *__xdrs));
 131         /* returns bytes off from beginning */
 132         bool_t (*x_setpostn) __PMT ((XDR *__xdrs, u_int pos));
 133         /* lets you reposition the stream */
 134         long *(*x_inline) __PMT ((XDR *__xdrs, int len));
 135         /* buf quick ptr to buffered data */
 136         void (*x_destroy) __PMT ((XDR *__xdrs));
 137         /* free privates of this xdr_stream */
 138       }
 139      *x_ops;
 140     caddr_t x_public;           /* users' data */
 141     caddr_t x_private;          /* pointer to private data */
 142     caddr_t x_base;             /* private used for position info */
 143     int x_handy;                /* extra private word */
 144   };
 145
 146 /*
 147  * A xdrproc_t exists for each data type which is to be encoded or decoded.
 148  *
 149  * The second argument to the xdrproc_t is a pointer to an opaque pointer.
 150  * The opaque pointer generally points to a structure of the data type
 151  * to be decoded.  If this pointer is 0, then the type routines should
 152  * allocate dynamic storage of the appropriate size and return it.
 153  * bool_t       (*xdrproc_t)(XDR *, caddr_t *);
 154  */
 155 typedef bool_t (*xdrproc_t) __PMT ((XDR *, void *,...));
 156
 157 /*
 158  * Operations defined on a XDR handle
 159  *
 160  * XDR          *xdrs;
 161  * long         *longp;
 162  * caddr_t       addr;
 163  * u_int         len;
 164  * u_int         pos;
 165  */
 166 #define XDR_GETINT32(xdrs, int32p)                      \
 167         (*(xdrs)->x_ops->x_getlong)(xdrs, (long *)int32p)
 168 #define xdr_getint32(xdrs, int32p)                      \
 169         (*(xdrs)->x_ops->x_getlong)(xdrs, (long *)int32p)
 170
 171 #define XDR_PUTINT32(xdrs, int32p)                      \
 172         (*(xdrs)->x_ops->x_putlong)(xdrs, (long *)int32p)
 173 #define xdr_putint32(xdrs, int32p)                      \
 174         (*(xdrs)->x_ops->x_putlong)(xdrs, (long *)int32p)
 175
 176 #define XDR_GETLONG(xdrs, longp)                        \
 177         (*(xdrs)->x_ops->x_getlong)(xdrs, longp)
 178 #define xdr_getlong(xdrs, longp)                        \
 179         (*(xdrs)->x_ops->x_getlong)(xdrs, longp)
 180
 181 #define XDR_PUTLONG(xdrs, longp)                        \
 182         (*(xdrs)->x_ops->x_putlong)(xdrs, longp)
 183 #define xdr_putlong(xdrs, longp)                        \
 184         (*(xdrs)->x_ops->x_putlong)(xdrs, longp)
 185
 186 #define XDR_GETBYTES(xdrs, addr, len)                   \
 187         (*(xdrs)->x_ops->x_getbytes)(xdrs, addr, len)
 188 #define xdr_getbytes(xdrs, addr, len)                   \
 189         (*(xdrs)->x_ops->x_getbytes)(xdrs, addr, len)
 190
 191 #define XDR_PUTBYTES(xdrs, addr, len)                   \
 192         (*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)
 193 #define xdr_putbytes(xdrs, addr, len)                   \
 194         (*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)
 195
 196 #define XDR_GETPOS(xdrs)                                \
 197         (*(xdrs)->x_ops->x_getpostn)(xdrs)
 198 #define xdr_getpos(xdrs)                                \
 199         (*(xdrs)->x_ops->x_getpostn)(xdrs)
 200
 201 #define XDR_SETPOS(xdrs, pos)                           \
 202         (*(xdrs)->x_ops->x_setpostn)(xdrs, pos)
 203 #define xdr_setpos(xdrs, pos)                           \
 204         (*(xdrs)->x_ops->x_setpostn)(xdrs, pos)
 205
 206 #define XDR_INLINE(xdrs, len)                           \
 207         (*(xdrs)->x_ops->x_inline)(xdrs, len)
 208 #define xdr_inline(xdrs, len)                           \
 209         (*(xdrs)->x_ops->x_inline)(xdrs, len)
 210
 211 #define XDR_DESTROY(xdrs)                               \
 212         if ((xdrs)->x_ops->x_destroy)                   \
 213                 (*(xdrs)->x_ops->x_destroy)(xdrs)
 214 #define xdr_destroy(xdrs)                               \
 215         if ((xdrs)->x_ops->x_destroy)                   \
 216                 (*(xdrs)->x_ops->x_destroy)(xdrs)
 217
 218 /*
 219  * Support struct for discriminated unions.
 220  * You create an array of xdrdiscrim structures, terminated with
 221  * a entry with a null procedure pointer.  The xdr_union routine gets
 222  * the discriminant value and then searches the array of structures
 223  * for a matching value.  If a match is found the associated xdr routine
 224  * is called to handle that part of the union.  If there is
 225  * no match, then a default routine may be called.
 226  * If there is no match and no default routine it is an error.
 227  */
 228 #define NULL_xdrproc_t ((xdrproc_t)0)
 229 struct xdr_discrim
 230 {
 231   int value;
 232   xdrproc_t proc;
 233 };
 234
 235 /*
 236  * Inline routines for fast encode/decode of primitive data types.
 237  * Caveat emptor: these use single memory cycles to get the
 238  * data from the underlying buffer, and will fail to operate
 239  * properly if the data is not aligned.  The standard way to use these
 240  * is to say:
 241  *      if ((buf = XDR_INLINE(xdrs, count)) == NULL)
 242  *              return (FALSE);
 243  *      <<< macro calls >>>
 244  * where ``count'' is the number of bytes of data occupied
 245  * by the primitive data types.
 246  *
 247  * N.B. and frozen for all time: each data type here uses 4 bytes
 248  * of external representation.
 249  */
 250 #define IXDR_GET_LONG(buf)              ((long)ntohl((u_long)*((u_int32_t*)buf)++))
 251 #define IXDR_PUT_LONG(buf, v)           (*((u_int32_t*)(buf))++ = (long)htonl((u_long)v))
 252
 253 #define IXDR_GET_BOOL(buf)              ((bool_t)IXDR_GET_LONG(buf))
 254 #define IXDR_GET_ENUM(buf, t)           ((t)IXDR_GET_LONG(buf))
 255 #define IXDR_GET_U_LONG(buf)            ((u_long)IXDR_GET_LONG(buf))
 256 #define IXDR_GET_SHORT(buf)             ((short)IXDR_GET_LONG(buf))
 257 #define IXDR_GET_U_SHORT(buf)           ((u_short)IXDR_GET_LONG(buf))
 258
 259 #define IXDR_PUT_BOOL(buf, v)           IXDR_PUT_LONG((buf), ((long)(v)))
 260 #define IXDR_PUT_ENUM(buf, v)           IXDR_PUT_LONG((buf), ((long)(v)))
 261 #define IXDR_PUT_U_LONG(buf, v)         IXDR_PUT_LONG((buf), ((long)(v)))
 262 #define IXDR_PUT_SHORT(buf, v)          IXDR_PUT_LONG((buf), ((long)(v)))
 263 #define IXDR_PUT_U_SHORT(buf, v)        IXDR_PUT_LONG((buf), ((long)(v)))
 264
 265 /*
 266  * These are the "generic" xdr routines.
 267  * None of these can have const applied because it's not possible to
 268  * know whether the call is a read or a write to the passed parameter
 269  * also, the XDR structure is always updated by some of these calls.
 270  */
 271 extern bool_t xdr_void __P ((void));
 272 extern bool_t xdr_int __P ((XDR *__xdrs, int *__ip));
 273 extern bool_t xdr_u_int __P ((XDR *__xdrs, u_int *__up));
 274 extern bool_t xdr_int32_t __P ((XDR *__xdrs, int32_t *__ip));
 275 extern bool_t xdr_uint32_t __P ((XDR *__xdrs, uint32_t *__up));
 276 extern bool_t xdr_long __P ((XDR *__xdrs, long *__lp));
 277 extern bool_t xdr_u_long __P ((XDR *__xdrs, u_long *__ulp));
 278 extern bool_t xdr_short __P ((XDR *__xdrs, short *__sp));
 279 extern bool_t xdr_u_short __P ((XDR *__xdrs, u_short *__usp));
 280 extern bool_t xdr_bool __P ((XDR *__xdrs, bool_t *__bp));
 281 extern bool_t xdr_enum __P ((XDR *__xdrs, enum_t *__ep));
 282 extern bool_t xdr_array __P ((XDR * _xdrs, caddr_t *__addrp, u_int *__sizep,
 283                               u_int __maxsize, u_int __elsize,
 284                               xdrproc_t __elproc));
 285 extern bool_t xdr_bytes __P ((XDR *__xdrs, char **__cpp, u_int *__sizep,
 286                               u_int __maxsize));
 287 extern bool_t xdr_opaque __P ((XDR *__xdrs, caddr_t __cp, u_int __cnt));
 288 extern bool_t xdr_string __P ((XDR *__xdrs, char **__cpp, u_int __maxsize));
 289 extern bool_t xdr_union __P ((XDR *__xdrs, enum_t *__dscmp, char *__unp,
 290                               __const struct xdr_discrim *__choices,
 291                               xdrproc_t dfault));
 292 extern bool_t xdr_char __P ((XDR *__xdrs, char *__cp));
 293 extern bool_t xdr_u_char __P ((XDR *__xdrs, u_char *__cp));
 294 extern bool_t xdr_vector __P ((XDR *__xdrs, char *__basep, u_int __nelem,
 295                                u_int __elemsize, xdrproc_t __xdr_elem));
 296 extern bool_t xdr_float __P ((XDR *__xdrs, float *__fp));
 297 extern bool_t xdr_double __P ((XDR *__xdrs, double *__dp));
 298 extern bool_t xdr_reference __P ((XDR *__xdrs, caddr_t *__xpp, u_int __size,
 299                                   xdrproc_t __proc));
 300 extern bool_t xdr_pointer __P ((XDR *__xdrs, char **__objpp,
 301                                 u_int __obj_size, xdrproc_t __xdr_obj));
 302 extern bool_t xdr_wrapstring __P ((XDR *__xdrs, char **__cpp));
 303 extern u_long xdr_sizeof __P ((xdrproc_t, void *));
 304
 305 /*
 306  * Common opaque bytes objects used by many rpc protocols;
 307  * declared here due to commonality.
 308  */
 309 #define MAX_NETOBJ_SZ 1024
 310 struct netobj
 311 {
 312   u_int n_len;
 313   char *n_bytes;
 314 };
 315 typedef struct netobj netobj;
 316 extern bool_t xdr_netobj __P ((XDR *__xdrs, struct netobj *__np));
 317
 318 /*
 319  * These are the public routines for the various implementations of
 320  * xdr streams.
 321  */
 322
 323 /* XDR using memory buffers */
 324 extern void xdrmem_create __P ((XDR *__xdrs, __const caddr_t __addr,
 325                                 u_int __size, enum xdr_op __xop));
 326
 327 /* XDR using stdio library */
 328 extern void xdrstdio_create __P ((XDR *__xdrs, FILE *__file,
 329                                   enum xdr_op __xop));
 330
 331 /* XDR pseudo records for tcp */
 332 extern void xdrrec_create __P ((XDR *__xdrs, u_int __sendsize,
 333                                 u_int __recvsize, caddr_t __tcp_handle,
 334                                 int (*__readit) (char *, char *, int),
 335                                 int (*__writeit) (char *, char *, int)));
 336
 337 /* make end of xdr record */
 338 extern bool_t xdrrec_endofrecord __P ((XDR *__xdrs, bool_t __sendnow));
 339
 340 /* move to beginning of next record */
 341 extern bool_t xdrrec_skiprecord __P ((XDR *__xdrs));
 342
 343 /* true if no more input */
 344 extern bool_t xdrrec_eof __P ((XDR *__xdrs));
 345
 346 /* free memory buffers for xdr */
 347 extern void xdr_free __P ((xdrproc_t __proc, char *__objp));
 348
 349 __END_DECLS
 350
 351 #endif /* rpc/xdr.h */