lib/libc/xdr/xdr_sizeof.c

   1 /*
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   7  * program developed by the user.
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   9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
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  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  * $DragonFly: src/lib/libc/xdr/xdr_sizeof.c,v 1.2 2005/12/05 00:47:57 swildner Exp $
  30  */
  31
  32 /*
  33  * xdr_sizeof.c
  34  *
  35  * Copyright 1990 Sun Microsystems, Inc.
  36  *
  37  * General purpose routine to see how much space something will use
  38  * when serialized using XDR.
  39  */
  40
  41 #include <rpc/types.h>
  42 #include <rpc/xdr.h>
  43 #include <sys/types.h>
  44 #include <stdlib.h>
  45
  46 /* ARGSUSED */
  47 static bool_t
  48 x_putlong(XDR *xdrs, long *longp __unused)
  49 {
  50         xdrs->x_handy += BYTES_PER_XDR_UNIT;
  51         return (TRUE);
  52 }
  53
  54 /* ARGSUSED */
  55 static bool_t
  56 x_putbytes(XDR *xdrs, char *bp __unused, u_int len)
  57 {
  58         xdrs->x_handy += len;
  59         return (TRUE);
  60 }
  61
  62 static u_int
  63 x_getpostn(XDR *xdrs)
  64 {
  65         return (xdrs->x_handy);
  66 }
  67
  68 /* ARGSUSED */
  69 static bool_t
  70 x_setpostn(XDR *xdrs __unused, u_int pos __unused)
  71 {
  72         /* This is not allowed */
  73         return (FALSE);
  74 }
  75
  76 static int32_t *
  77 x_inline(XDR *xdrs, long len)
  78 {
  79         if (len == 0) {
  80                 return (NULL);
  81         }
  82         if (xdrs->x_op != XDR_ENCODE) {
  83                 return (NULL);
  84         }
  85         if (len < (long) xdrs->x_base) {
  86                 /* x_private was already allocated */
  87                 xdrs->x_handy += len;
  88                 return ((int32_t *) xdrs->x_private);
  89         } else {
  90                 /* Free the earlier space and allocate new area */
  91                 if (xdrs->x_private)
  92                         free(xdrs->x_private);
  93                 if ((xdrs->x_private = (caddr_t) malloc(len)) == NULL) {
  94                         xdrs->x_base = 0;
  95                         return (NULL);
  96                 }
  97                 xdrs->x_base = (caddr_t) len;
  98                 xdrs->x_handy += len;
  99                 return ((int32_t *) xdrs->x_private);
 100         }
 101 }
 102
 103 static int
 104 harmless(void)
 105 {
 106         /* Always return FALSE/NULL, as the case may be */
 107         return (0);
 108 }
 109
 110 static void
 111 x_destroy(XDR *xdrs)
 112 {
 113         xdrs->x_handy = 0;
 114         xdrs->x_base = 0;
 115         if (xdrs->x_private) {
 116                 free(xdrs->x_private);
 117                 xdrs->x_private = NULL;
 118         }
 119         return;
 120 }
 121
 122 unsigned long
 123 xdr_sizeof(xdrproc_t func, void *data)
 124 {
 125         XDR x;
 126         struct xdr_ops ops;
 127         bool_t stat;
 128         /* to stop ANSI-C compiler from complaining */
 129         typedef  bool_t (* dummyfunc1)(XDR *, long *);
 130         typedef  bool_t (* dummyfunc2)(XDR *, caddr_t, u_int);
 131
 132         ops.x_putlong = x_putlong;
 133         ops.x_putbytes = x_putbytes;
 134         ops.x_inline = x_inline;
 135         ops.x_getpostn = x_getpostn;
 136         ops.x_setpostn = x_setpostn;
 137         ops.x_destroy = x_destroy;
 138
 139         /* the other harmless ones */
 140         ops.x_getlong =  (dummyfunc1) harmless;
 141         ops.x_getbytes = (dummyfunc2) harmless;
 142
 143         x.x_op = XDR_ENCODE;
 144         x.x_ops = &ops;
 145         x.x_handy = 0;
 146         x.x_private = (caddr_t) NULL;
 147         x.x_base = (caddr_t) 0;
 148
 149         stat = func(&x, data);
 150         if (x.x_private)
 151                 free(x.x_private);
 152         return (stat == TRUE ? (unsigned) x.x_handy: 0);
 153 }