lib/libc/rpc/xdr_sizeof.c

   1 /*
   2  * Copyright (c) 2010, Oracle America, Inc.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  *     * Redistributions of source code must retain the above copyright
   9  *       notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  *       copyright notice, this list of conditions and the following
  12  *       disclaimer in the documentation and/or other materials
  13  *       provided with the distribution.
  14  *     * Neither the name of the "Oracle America, Inc." nor the names of its
  15  *       contributors may be used to endorse or promote products derived
  16  *       from this software without specific prior written permission.
  17  *
  18  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  21  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  22  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  23  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  25  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  27  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  28  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31 /*
  32  * xdr_sizeof.c
  33  *
  34  * Copyright 1990 Sun Microsystems, Inc.
  35  *
  36  * General purpose routine to see how much space something will use
  37  * when serialized using XDR.
  38  */
  39
  40 #include <sys/cdefs.h>
  41 #if 0
  42 __FBSDID("$FreeBSD: src/lib/libc/xdr/xdr_sizeof.c,v 1.5.38.1 2010/12/21 17:10:29 kensmith Exp $");
  43 #else
  44 __RCSID("$NetBSD: xdr_sizeof.c,v 1.5 2013/03/11 20:19:30 tron Exp $");
  45 #endif
  46
  47 #include "namespace.h"
  48 #include <rpc/types.h>
  49 #include <rpc/xdr.h>
  50 #include <sys/types.h>
  51 #include <stdlib.h>
  52
  53 #ifdef __weak_alias
  54 __weak_alias(xdr_sizeof,_xdr_sizeof)
  55 #endif
  56
  57 static bool_t x_putlong(XDR *, const long *);
  58 static bool_t x_putbytes(XDR *, const char *, u_int);
  59 static u_int x_getpostn(XDR *);
  60 static bool_t x_setpostn(XDR *, u_int);
  61 static int32_t *x_inline(XDR *, u_int);
  62 static int harmless(void);
  63 static void x_destroy(XDR *);
  64
  65 /* ARGSUSED */
  66 static bool_t
  67 x_putlong(XDR *xdrs, const long *longp)
  68 {
  69         xdrs->x_handy += BYTES_PER_XDR_UNIT;
  70         return (TRUE);
  71 }
  72
  73 /* ARGSUSED */
  74 static bool_t
  75 x_putbytes(XDR *xdrs, const char *bp, u_int len)
  76 {
  77         xdrs->x_handy += len;
  78         return (TRUE);
  79 }
  80
  81 static u_int
  82 x_getpostn(XDR *xdrs)
  83 {
  84         return (xdrs->x_handy);
  85 }
  86
  87 /* ARGSUSED */
  88 static bool_t
  89 x_setpostn(XDR *xdrs, u_int pos)
  90 {
  91         /* This is not allowed */
  92         return (FALSE);
  93 }
  94
  95 static int32_t *
  96 x_inline(XDR *xdrs, u_int len)
  97 {
  98         if (len == 0) {
  99                 return (NULL);
 100         }
 101         if (xdrs->x_op != XDR_ENCODE) {
 102                 return (NULL);
 103         }
 104         if (len < (u_int)(uintptr_t)xdrs->x_base) {
 105                 /* x_private was already allocated */
 106                 xdrs->x_handy += len;
 107                 return ((int32_t *) xdrs->x_private);
 108         } else {
 109                 /* Free the earlier space and allocate new area */
 110                 if (xdrs->x_private)
 111                         free(xdrs->x_private);
 112                 if ((xdrs->x_private = malloc(len)) == NULL) {
 113                         xdrs->x_base = 0;
 114                         return (NULL);
 115                 }
 116                 xdrs->x_base = (caddr_t)(uintptr_t)len;
 117                 xdrs->x_handy += len;
 118                 return ((int32_t *) xdrs->x_private);
 119         }
 120 }
 121
 122 static int
 123 harmless(void)
 124 {
 125         /* Always return FALSE/NULL, as the case may be */
 126         return (0);
 127 }
 128
 129 static void
 130 x_destroy(XDR *xdrs)
 131 {
 132         xdrs->x_handy = 0;
 133         xdrs->x_base = 0;
 134         if (xdrs->x_private) {
 135                 free(xdrs->x_private);
 136                 xdrs->x_private = NULL;
 137         }
 138         return;
 139 }
 140
 141 unsigned long
 142 xdr_sizeof(xdrproc_t func, void *data)
 143 {
 144         XDR x;
 145         struct xdr_ops ops;
 146         bool_t stat;
 147         /* to stop ANSI-C compiler from complaining */
 148         typedef  bool_t (* dummyfunc1)(XDR *, long *);
 149         typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, u_int);
 150
 151         ops.x_putlong = x_putlong;
 152         ops.x_putbytes = x_putbytes;
 153         ops.x_inline = x_inline;
 154         ops.x_getpostn = x_getpostn;
 155         ops.x_setpostn = x_setpostn;
 156         ops.x_destroy = x_destroy;
 157
 158         /* the other harmless ones */
 159         ops.x_getlong =  (dummyfunc1) harmless;
 160         ops.x_getbytes = (dummyfunc2) harmless;
 161
 162         x.x_op = XDR_ENCODE;
 163         x.x_ops = &ops;
 164         x.x_handy = 0;
 165         x.x_private = (caddr_t) NULL;
 166         x.x_base = (caddr_t) 0;
 167
 168         stat = func(&x, data);
 169         if (x.x_private)
 170                 free(x.x_private);
 171         return (stat == TRUE ? (unsigned) x.x_handy: 0);
 172 }