lib/libc/xdr/xdr_sizeof.c

   1 /*
   2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   3  * unrestricted use provided that this legend is included on all tape
   4  * media and as a part of the software program in whole or part.  Users
   5  * may copy or modify Sun RPC without charge, but are not authorized
   6  * to license or distribute it to anyone else except as part of a product or
   7  * program developed by the user.
   8  *
   9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  12  *
  13  * Sun RPC is provided with no support and without any obligation on the
  14  * part of Sun Microsystems, Inc. to assist in its use, correction,
  15  * modification or enhancement.
  16  *
  17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  19  * OR ANY PART THEREOF.
  20  *
  21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  22  * or profits or other special, indirect and consequential damages, even if
  23  * Sun has been advised of the possibility of such damages.
  24  *
  25  * Sun Microsystems, Inc.
  26  * 2550 Garcia Avenue
  27  * Mountain View, California  94043
  28  *
  29  * $FreeBSD: src/lib/libc/xdr/xdr_sizeof.c,v 1.5 2003/03/07 13:19:40 nectar Exp $
  30  * $DragonFly: src/lib/libc/xdr/xdr_sizeof.c,v 1.2 2005/12/05 00:47:57 swildner Exp $
  31  */
  32
  33 /*
  34  * xdr_sizeof.c
  35  *
  36  * Copyright 1990 Sun Microsystems, Inc.
  37  *
  38  * General purpose routine to see how much space something will use
  39  * when serialized using XDR.
  40  */
  41
  42 #include "namespace.h"
  43 #include <rpc/types.h>
  44 #include <rpc/xdr.h>
  45 #include <sys/types.h>
  46 #include <stdlib.h>
  47 #include "un-namespace.h"
  48
  49 /* ARGSUSED */
  50 static bool_t
  51 x_putlong(XDR *xdrs, long *longp __unused)
  52 {
  53         xdrs->x_handy += BYTES_PER_XDR_UNIT;
  54         return (TRUE);
  55 }
  56
  57 /* ARGSUSED */
  58 static bool_t
  59 x_putbytes(XDR *xdrs, char *bp __unused, u_int len)
  60 {
  61         xdrs->x_handy += len;
  62         return (TRUE);
  63 }
  64
  65 static u_int
  66 x_getpostn(XDR *xdrs)
  67 {
  68         return (xdrs->x_handy);
  69 }
  70
  71 /* ARGSUSED */
  72 static bool_t
  73 x_setpostn(XDR *xdrs __unused, u_int pos __unused)
  74 {
  75         /* This is not allowed */
  76         return (FALSE);
  77 }
  78
  79 static int32_t *
  80 x_inline(XDR *xdrs, u_int len)
  81 {
  82         if (len == 0) {
  83                 return (NULL);
  84         }
  85         if (xdrs->x_op != XDR_ENCODE) {
  86                 return (NULL);
  87         }
  88         if (len < (u_int)xdrs->x_base) {
  89                 /* x_private was already allocated */
  90                 xdrs->x_handy += len;
  91                 return ((int32_t *) xdrs->x_private);
  92         } else {
  93                 /* Free the earlier space and allocate new area */
  94                 if (xdrs->x_private)
  95                         free(xdrs->x_private);
  96                 if ((xdrs->x_private = (caddr_t) malloc(len)) == NULL) {
  97                         xdrs->x_base = 0;
  98                         return (NULL);
  99                 }
 100                 xdrs->x_base = (caddr_t) len;
 101                 xdrs->x_handy += len;
 102                 return ((int32_t *) xdrs->x_private);
 103         }
 104 }
 105
 106 static int
 107 harmless(void)
 108 {
 109         /* Always return FALSE/NULL, as the case may be */
 110         return (0);
 111 }
 112
 113 static void
 114 x_destroy(XDR *xdrs)
 115 {
 116         xdrs->x_handy = 0;
 117         xdrs->x_base = 0;
 118         if (xdrs->x_private) {
 119                 free(xdrs->x_private);
 120                 xdrs->x_private = NULL;
 121         }
 122         return;
 123 }
 124
 125 unsigned long
 126 xdr_sizeof(xdrproc_t func, void *data)
 127 {
 128         XDR x;
 129         struct xdr_ops ops;
 130         bool_t stat;
 131         /* to stop ANSI-C compiler from complaining */
 132         typedef  bool_t (* dummyfunc1)(XDR *, long *);
 133         typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, u_int);
 134
 135         ops.x_putlong = x_putlong;
 136         ops.x_putbytes = x_putbytes;
 137         ops.x_inline = x_inline;
 138         ops.x_getpostn = x_getpostn;
 139         ops.x_setpostn = x_setpostn;
 140         ops.x_destroy = x_destroy;
 141
 142         /* the other harmless ones */
 143         ops.x_getlong =  (dummyfunc1) harmless;
 144         ops.x_getbytes = (dummyfunc2) harmless;
 145
 146         x.x_op = XDR_ENCODE;
 147         x.x_ops = &ops;
 148         x.x_handy = 0;
 149         x.x_private = (caddr_t) NULL;
 150         x.x_base = (caddr_t) 0;
 151
 152         stat = func(&x, data);
 153         if (x.x_private)
 154                 free(x.x_private);
 155         return (stat == TRUE ? (unsigned) x.x_handy: 0);
 156 }