sunrpc/xdr_sizeof.c

   1 /*
   2  * xdr_sizeof.c
   3  *
   4  * Copyright (c) 2010, Oracle America, Inc.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are
   8  * met:
   9  *
  10  *     * Redistributions of source code must retain the above copyright
  11  *       notice, this list of conditions and the following disclaimer.
  12  *     * Redistributions in binary form must reproduce the above
  13  *       copyright notice, this list of conditions and the following
  14  *       disclaimer in the documentation and/or other materials
  15  *       provided with the distribution.
  16  *     * Neither the name of the "Oracle America, Inc." nor the names of its
  17  *       contributors may be used to endorse or promote products derived
  18  *       from this software without specific prior written permission.
  19  *
  20  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  24  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  25  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  27  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  28  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  29  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  *
  33  * General purpose routine to see how much space something will use
  34  * when serialized using XDR.
  35  */
  36
  37 #include <rpc/types.h>
  38 #include <rpc/xdr.h>
  39 #include <sys/types.h>
  40 #include <stdlib.h>
  41
  42 /* ARGSUSED */
  43 static bool_t
  44 x_putlong (XDR *xdrs, const long *longp)
  45 {
  46   xdrs->x_handy += BYTES_PER_XDR_UNIT;
  47   return TRUE;
  48 }
  49
  50 /* ARGSUSED */
  51 static bool_t
  52 x_putbytes (XDR *xdrs, const char *bp, u_int len)
  53 {
  54   xdrs->x_handy += len;
  55   return TRUE;
  56 }
  57
  58 static u_int
  59 x_getpostn (const XDR *xdrs)
  60 {
  61   return xdrs->x_handy;
  62 }
  63
  64 /* ARGSUSED */
  65 static bool_t
  66 x_setpostn (XDR *xdrs, u_int len)
  67 {
  68   /* This is not allowed */
  69   return FALSE;
  70 }
  71
  72 static int32_t *
  73 x_inline (XDR *xdrs, u_int len)
  74 {
  75   if (len == 0)
  76     return NULL;
  77   if (xdrs->x_op != XDR_ENCODE)
  78     return NULL;
  79   if (len < (u_int) (long int) xdrs->x_base)
  80     {
  81       /* x_private was already allocated */
  82       xdrs->x_handy += len;
  83       return (int32_t *) xdrs->x_private;
  84     }
  85   else
  86     {
  87       /* Free the earlier space and allocate new area */
  88       free (xdrs->x_private);
  89       if ((xdrs->x_private = (caddr_t) malloc (len)) == NULL)
  90         {
  91           xdrs->x_base = 0;
  92           return NULL;
  93         }
  94       xdrs->x_base = (void *) (long) len;
  95       xdrs->x_handy += len;
  96       return (int32_t *) xdrs->x_private;
  97     }
  98 }
  99
 100 static int
 101 harmless (void)
 102 {
 103   /* Always return FALSE/NULL, as the case may be */
 104   return 0;
 105 }
 106
 107 static void
 108 x_destroy (XDR *xdrs)
 109 {
 110   xdrs->x_handy = 0;
 111   xdrs->x_base = 0;
 112   if (xdrs->x_private)
 113     {
 114       free (xdrs->x_private);
 115       xdrs->x_private = NULL;
 116     }
 117   return;
 118 }
 119
 120 static bool_t
 121 x_putint32 (XDR *xdrs, const int32_t *int32p)
 122 {
 123   xdrs->x_handy += BYTES_PER_XDR_UNIT;
 124   return TRUE;
 125 }
 126
 127 unsigned long
 128 xdr_sizeof (xdrproc_t func, void *data)
 129 {
 130   XDR x;
 131   struct xdr_ops ops;
 132   bool_t stat;
 133   /* to stop ANSI-C compiler from complaining */
 134   typedef bool_t (*dummyfunc1) (XDR *, long *);
 135   typedef bool_t (*dummyfunc2) (XDR *, caddr_t, u_int);
 136   typedef bool_t (*dummyfunc3) (XDR *, int32_t *);
 137
 138   ops.x_putlong = x_putlong;
 139   ops.x_putbytes = x_putbytes;
 140   ops.x_inline = x_inline;
 141   ops.x_getpostn = x_getpostn;
 142   ops.x_setpostn = x_setpostn;
 143   ops.x_destroy = x_destroy;
 144   ops.x_putint32 = x_putint32;
 145
 146   /* the other harmless ones */
 147   ops.x_getlong = (dummyfunc1) harmless;
 148   ops.x_getbytes = (dummyfunc2) harmless;
 149   ops.x_getint32 = (dummyfunc3) harmless;
 150
 151   x.x_op = XDR_ENCODE;
 152   x.x_ops = &ops;
 153   x.x_handy = 0;
 154   x.x_private = (caddr_t) NULL;
 155   x.x_base = (caddr_t) 0;
 156
 157   stat = func (&x, data);
 158   free (x.x_private);
 159   return stat == TRUE ? x.x_handy : 0;
 160 }
 161 #ifdef EXPORT_RPC_SYMBOLS
 162 libc_hidden_def (xdr_sizeof)
 163 #else
 164 libc_hidden_nolink (xdr_sizeof, GLIBC_2_1)
 165 #endif