usr/src/lib/libbc/inc/include/rpc/xdr.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 1984 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #ifndef _rpc_xdr_h
  28 #define _rpc_xdr_h
  29
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31
  32 /*
  33  * xdr.h, External Data Representation Serialization Routines.
  34  */
  35
  36 #include <rpc/types.h>
  37 /*
  38  * XDR provides a conventional way for converting between C data
  39  * types and an external bit-string representation.  Library supplied
  40  * routines provide for the conversion on built-in C data types.  These
  41  * routines and utility routines defined here are used to help implement
  42  * a type encode/decode routine for each user-defined type.
  43  *
  44  * Each data type provides a single procedure which takes two arguments:
  45  *
  46  *      bool_t
  47  *      xdrproc(xdrs, argresp)
  48  *              XDR *xdrs;
  49  *              <type> *argresp;
  50  *
  51  * xdrs is an instance of a XDR handle, to which or from which the data
  52  * type is to be converted.  argresp is a pointer to the structure to be
  53  * converted.  The XDR handle contains an operation field which indicates
  54  * which of the operations (ENCODE, DECODE * or FREE) is to be performed.
  55  *
  56  * XDR_DECODE may allocate space if the pointer argresp is null.  This
  57  * data can be freed with the XDR_FREE operation.
  58  *
  59  * We write only one procedure per data type to make it easy
  60  * to keep the encode and decode procedures for a data type consistent.
  61  * In many cases the same code performs all operations on a user defined type,
  62  * because all the hard work is done in the component type routines.
  63  * decode as a series of calls on the nested data types.
  64  */
  65
  66 /*
  67  * Xdr operations.  XDR_ENCODE causes the type to be encoded into the
  68  * stream.  XDR_DECODE causes the type to be extracted from the stream.
  69  * XDR_FREE can be used to release the space allocated by an XDR_DECODE
  70  * request.
  71  */
  72 enum xdr_op {
  73         XDR_ENCODE=0,
  74         XDR_DECODE=1,
  75         XDR_FREE=2
  76 };
  77
  78 /*
  79  * This is the number of bytes per unit of external data.
  80  */
  81 #define BYTES_PER_XDR_UNIT      (4)
  82 #define RNDUP(x)  ((((x) + BYTES_PER_XDR_UNIT - 1) / BYTES_PER_XDR_UNIT) \
  83                         * BYTES_PER_XDR_UNIT)
  84
  85 /*
  86  * A xdrproc_t exists for each data type which is to be encoded or decoded.
  87  *
  88  * The second argument to the xdrproc_t is a pointer to an opaque pointer.
  89  * The opaque pointer generally points to a structure of the data type
  90  * to be decoded.  If this pointer is 0, then the type routines should
  91  * allocate dynamic storage of the appropriate size and return it.
  92  * bool_t       (*xdrproc_t)(XDR *, caddr_t *);
  93  */
  94 typedef bool_t (*xdrproc_t)();
  95
  96 /*
  97  * The XDR handle.
  98  * Contains operation which is being applied to the stream,
  99  * an operations vector for the paticular implementation (e.g. see xdr_mem.c),
 100  * and two private fields for the use of the particular impelementation.
 101  */
 102 typedef struct {
 103         enum xdr_op     x_op;           /* operation; fast additional param */
 104         struct xdr_ops {
 105                 bool_t  (*x_getlong)(); /* get a long from underlying stream */
 106                 bool_t  (*x_putlong)(); /* put a long to " */
 107                 bool_t  (*x_getbytes)(); /* get some bytes from " */
 108                 bool_t  (*x_putbytes)(); /* put some bytes to " */
 109                 u_int   (*x_getpostn)(); /* returns bytes off from beginning */
 110                 bool_t  (*x_setpostn)(); /* lets you reposition the stream */
 111                 long *  (*x_inline)();  /* buf quick ptr to buffered data */
 112                 void    (*x_destroy)(); /* free privates of this xdr_stream */
 113         } *x_ops;
 114         caddr_t         x_public;       /* users' data */
 115         caddr_t         x_private;      /* pointer to private data */
 116         caddr_t         x_base;         /* private used for position info */
 117         int             x_handy;        /* extra private word */
 118 } XDR;
 119
 120 /*
 121  * Operations defined on a XDR handle
 122  *
 123  * XDR          *xdrs;
 124  * long         *longp;
 125  * caddr_t       addr;
 126  * u_int         len;
 127  * u_int         pos;
 128  */
 129 #define XDR_GETLONG(xdrs, longp)                        \
 130         (*(xdrs)->x_ops->x_getlong)(xdrs, longp)
 131 #define xdr_getlong(xdrs, longp)                        \
 132         (*(xdrs)->x_ops->x_getlong)(xdrs, longp)
 133
 134 #define XDR_PUTLONG(xdrs, longp)                        \
 135         (*(xdrs)->x_ops->x_putlong)(xdrs, longp)
 136 #define xdr_putlong(xdrs, longp)                        \
 137         (*(xdrs)->x_ops->x_putlong)(xdrs, longp)
 138
 139 #define XDR_GETBYTES(xdrs, addr, len)                   \
 140         (*(xdrs)->x_ops->x_getbytes)(xdrs, addr, len)
 141 #define xdr_getbytes(xdrs, addr, len)                   \
 142         (*(xdrs)->x_ops->x_getbytes)(xdrs, addr, len)
 143
 144 #define XDR_PUTBYTES(xdrs, addr, len)                   \
 145         (*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)
 146 #define xdr_putbytes(xdrs, addr, len)                   \
 147         (*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)
 148
 149 #define XDR_GETPOS(xdrs)                                \
 150         (*(xdrs)->x_ops->x_getpostn)(xdrs)
 151 #define xdr_getpos(xdrs)                                \
 152         (*(xdrs)->x_ops->x_getpostn)(xdrs)
 153
 154 #define XDR_SETPOS(xdrs, pos)                           \
 155         (*(xdrs)->x_ops->x_setpostn)(xdrs, pos)
 156 #define xdr_setpos(xdrs, pos)                           \
 157         (*(xdrs)->x_ops->x_setpostn)(xdrs, pos)
 158
 159 #define XDR_INLINE(xdrs, len)                           \
 160         (*(xdrs)->x_ops->x_inline)(xdrs, len)
 161 #define xdr_inline(xdrs, len)                           \
 162         (*(xdrs)->x_ops->x_inline)(xdrs, len)
 163
 164 #define XDR_DESTROY(xdrs)                               \
 165         (*(xdrs)->x_ops->x_destroy)(xdrs)
 166 #define xdr_destroy(xdrs) XDR_DESTROY(xdrs)
 167
 168 /*
 169  * Support struct for discriminated unions.
 170  * You create an array of xdrdiscrim structures, terminated with
 171  * a entry with a null procedure pointer.  The xdr_union routine gets
 172  * the discriminant value and then searches the array of structures
 173  * for a matching value.  If a match is found the associated xdr routine
 174  * is called to handle that part of the union.  If there is
 175  * no match, then a default routine may be called.
 176  * If there is no match and no default routine it is an error.
 177  */
 178 #define NULL_xdrproc_t ((xdrproc_t)0)
 179 struct xdr_discrim {
 180         int     value;
 181         xdrproc_t proc;
 182 };
 183
 184 /*
 185  * In-line routines for fast encode/decode of primitve data types.
 186  * Caveat emptor: these use single memory cycles to get the
 187  * data from the underlying buffer, and will fail to operate
 188  * properly if the data is not aligned.  The standard way to use these
 189  * is to say:
 190  *      if ((buf = XDR_INLINE(xdrs, count)) == NULL)
 191  *              return (FALSE);
 192  *      <<< macro calls >>>
 193  * where ``count'' is the number of bytes of data occupied
 194  * by the primitive data types.
 195  *
 196  * N.B. and frozen for all time: each data type here uses 4 bytes
 197  * of external representation.
 198  */
 199 #define IXDR_GET_LONG(buf)              ((long)ntohl((u_long)*(buf)++))
 200 #define IXDR_PUT_LONG(buf, v)           (*(buf)++ = (long)htonl((u_long)v))
 201
 202 #define IXDR_GET_BOOL(buf)              ((bool_t)IXDR_GET_LONG(buf))
 203 #define IXDR_GET_ENUM(buf, t)           ((t)IXDR_GET_LONG(buf))
 204 #define IXDR_GET_U_LONG(buf)            ((u_long)IXDR_GET_LONG(buf))
 205 #define IXDR_GET_SHORT(buf)             ((short)IXDR_GET_LONG(buf))
 206 #define IXDR_GET_U_SHORT(buf)           ((u_short)IXDR_GET_LONG(buf))
 207
 208 #define IXDR_PUT_BOOL(buf, v)           IXDR_PUT_LONG((buf), ((long)(v)))
 209 #define IXDR_PUT_ENUM(buf, v)           IXDR_PUT_LONG((buf), ((long)(v)))
 210 #define IXDR_PUT_U_LONG(buf, v)         IXDR_PUT_LONG((buf), ((long)(v)))
 211 #define IXDR_PUT_SHORT(buf, v)          IXDR_PUT_LONG((buf), ((long)(v)))
 212 #define IXDR_PUT_U_SHORT(buf, v)        IXDR_PUT_LONG((buf), ((long)(v)))
 213
 214 /*
 215  * These are the "generic" xdr routines.
 216  */
 217 extern bool_t   xdr_void();
 218 extern bool_t   xdr_int();
 219 extern bool_t   xdr_u_int();
 220 extern bool_t   xdr_long();
 221 extern bool_t   xdr_u_long();
 222 extern bool_t   xdr_short();
 223 extern bool_t   xdr_u_short();
 224 extern bool_t   xdr_bool();
 225 extern bool_t   xdr_enum();
 226 extern bool_t   xdr_array();
 227 extern bool_t   xdr_bytes();
 228 extern bool_t   xdr_opaque();
 229 extern bool_t   xdr_string();
 230 extern bool_t   xdr_union();
 231 extern void     xdr_free();
 232 extern bool_t   xdr_char();
 233 extern bool_t   xdr_u_char();
 234 extern bool_t   xdr_vector();
 235 extern bool_t   xdr_float();
 236 extern bool_t   xdr_double();
 237 extern bool_t   xdr_reference();
 238 extern bool_t   xdr_pointer();
 239 extern bool_t   xdr_wrapstring();
 240
 241 /*
 242  * Common opaque bytes objects used by many rpc protocols;
 243  * declared here due to commonality.
 244  */
 245 #define MAX_NETOBJ_SZ 1024
 246 struct netobj {
 247         u_int   n_len;
 248         char    *n_bytes;
 249 };
 250 typedef struct netobj netobj;
 251 extern bool_t   xdr_netobj();
 252
 253 /*
 254  * These are the public routines for the various implementations of
 255  * xdr streams.
 256  */
 257 extern void     xdrmem_create();        /* XDR using memory buffers */
 258 extern void     xdrstdio_create();      /* XDR using stdio library */
 259 extern void     xdrrec_create();        /* XDR pseudo records for tcp */
 260 extern bool_t   xdrrec_endofrecord();   /* make end of xdr record */
 261 extern int      xdrrec_readbytes();     /* like a read on a pipe */
 262 extern bool_t   xdrrec_skiprecord();    /* move to beginning of next record */
 263 extern bool_t   xdrrec_eof();           /* true if no more input */
 264
 265 #endif /* !_rpc_xdr_h */