include/os/linux/spl/rpc/xdr.h

   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 typedef int bool_t;
  27
  28 /*
  29  * XDR enums and types.
  30  */
  31 enum xdr_op {
  32         XDR_ENCODE,
  33         XDR_DECODE
  34 };
  35
  36 struct xdr_ops;
  37
  38 typedef struct {
  39         const struct xdr_ops    *x_ops;
  40             /* Let caller know xdrmem_create() succeeds */
  41         caddr_t         x_addr; /* Current buffer addr */
  42         caddr_t         x_addr_end;     /* End of the buffer */
  43         enum xdr_op     x_op;   /* Stream direction */
  44 } XDR;
  45
  46 typedef bool_t (*xdrproc_t)(XDR *xdrs, void *ptr);
  47
  48 struct xdr_ops {
  49         bool_t (*xdr_control)(XDR *, int, void *);
  50
  51         bool_t (*xdr_char)(XDR *, char *);
  52         bool_t (*xdr_u_short)(XDR *, unsigned short *);
  53         bool_t (*xdr_u_int)(XDR *, unsigned *);
  54         bool_t (*xdr_u_longlong_t)(XDR *, u_longlong_t *);
  55
  56         bool_t (*xdr_opaque)(XDR *, caddr_t, const uint_t);
  57         bool_t (*xdr_string)(XDR *, char **, const uint_t);
  58         bool_t (*xdr_array)(XDR *, caddr_t *, uint_t *, const uint_t,
  59             const uint_t, const xdrproc_t);
  60 };
  61
  62 /*
  63  * XDR control operator.
  64  */
  65 #define XDR_GET_BYTES_AVAIL 1
  66
  67 struct xdr_bytesrec {
  68         bool_t xc_is_last_record;
  69         size_t xc_num_avail;
  70 };
  71
  72 /*
  73  * XDR functions.
  74  */
  75 void xdrmem_create(XDR *xdrs, const caddr_t addr, const uint_t size,
  76     const enum xdr_op op);
  77
  78 #define xdr_control(xdrs, req, info) \
  79         (xdrs)->x_ops->xdr_control((xdrs), (req), (info))
  80
  81 /*
  82  * For precaution, the following are defined as static inlines instead of macros
  83  * to get some amount of type safety.
  84  *
  85  * Also, macros wouldn't work in the case where typecasting is done, because it
  86  * must be possible to reference the functions' addresses by these names.
  87  */
  88 static inline bool_t xdr_char(XDR *xdrs, char *cp)
  89 {
  90         return (xdrs->x_ops->xdr_char(xdrs, cp));
  91 }
  92
  93 static inline bool_t xdr_u_short(XDR *xdrs, unsigned short *usp)
  94 {
  95         return (xdrs->x_ops->xdr_u_short(xdrs, usp));
  96 }
  97
  98 static inline bool_t xdr_short(XDR *xdrs, short *sp)
  99 {
 100         BUILD_BUG_ON(sizeof (short) != 2);
 101         return (xdrs->x_ops->xdr_u_short(xdrs, (unsigned short *) sp));
 102 }
 103
 104 static inline bool_t xdr_u_int(XDR *xdrs, unsigned *up)
 105 {
 106         return (xdrs->x_ops->xdr_u_int(xdrs, up));
 107 }
 108
 109 static inline bool_t xdr_int(XDR *xdrs, int *ip)
 110 {
 111         BUILD_BUG_ON(sizeof (int) != 4);
 112         return (xdrs->x_ops->xdr_u_int(xdrs, (unsigned *)ip));
 113 }
 114
 115 static inline bool_t xdr_u_longlong_t(XDR *xdrs, u_longlong_t *ullp)
 116 {
 117         return (xdrs->x_ops->xdr_u_longlong_t(xdrs, ullp));
 118 }
 119
 120 static inline bool_t xdr_longlong_t(XDR *xdrs, longlong_t *llp)
 121 {
 122         BUILD_BUG_ON(sizeof (longlong_t) != 8);
 123         return (xdrs->x_ops->xdr_u_longlong_t(xdrs, (u_longlong_t *)llp));
 124 }
 125
 126 /*
 127  * Fixed-length opaque data.
 128  */
 129 static inline bool_t xdr_opaque(XDR *xdrs, caddr_t cp, const uint_t cnt)
 130 {
 131         return (xdrs->x_ops->xdr_opaque(xdrs, cp, cnt));
 132 }
 133
 134 /*
 135  * Variable-length string.
 136  * The *sp buffer must have (maxsize + 1) bytes.
 137  */
 138 static inline bool_t xdr_string(XDR *xdrs, char **sp, const uint_t maxsize)
 139 {
 140         return (xdrs->x_ops->xdr_string(xdrs, sp, maxsize));
 141 }
 142
 143 /*
 144  * Variable-length arrays.
 145  */
 146 static inline bool_t xdr_array(XDR *xdrs, caddr_t *arrp, uint_t *sizep,
 147     const uint_t maxsize, const uint_t elsize, const xdrproc_t elproc)
 148 {
 149         return xdrs->x_ops->xdr_array(xdrs, arrp, sizep, maxsize, elsize,
 150             elproc);
 151 }
 152
 153 #endif /* SPL_RPC_XDR_H */