lib/libc/xdr/xdr_reference.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  * @(#)xdr_reference.c 1.11 87/08/11 SMI
  30  * @(#)xdr_reference.c  2.1 88/07/29 4.0 RPCSRC
  31  * $NetBSD: xdr_reference.c,v 1.13 2000/01/22 22:19:18 mycroft Exp $
  32  * $FreeBSD: src/lib/libc/xdr/xdr_reference.c,v 1.12 2004/10/16 06:32:43 obrien Exp $
  33  * $DragonFly: src/lib/libc/xdr/xdr_reference.c,v 1.4 2005/12/05 00:47:57 swildner Exp $
  34  */
  35
  36 /*
  37  * xdr_reference.c, Generic XDR routines impelmentation.
  38  *
  39  * Copyright (C) 1987, Sun Microsystems, Inc.
  40  *
  41  * These are the "non-trivial" xdr primitives used to serialize and de-serialize
  42  * "pointers".  See xdr.h for more info on the interface to xdr.
  43  */
  44
  45 #include "namespace.h"
  46 #include <err.h>
  47 #include <stdio.h>
  48 #include <stdlib.h>
  49 #include <string.h>
  50
  51 #include <rpc/types.h>
  52 #include <rpc/xdr.h>
  53 #include "libc_private.h"
  54
  55 /*
  56  * XDR an indirect pointer
  57  * xdr_reference is for recursively translating a structure that is
  58  * referenced by a pointer inside the structure that is currently being
  59  * translated.  pp references a pointer to storage. If *pp is null
  60  * the  necessary storage is allocated.
  61  * size is the sizeof the referneced structure.
  62  * proc is the routine to handle the referenced structure.
  63  *
  64  * Parameters:
  65  *     pp:      the pointer to work on
  66  *     size:    size of the object pointed to
  67  *     proc:    xdr routine to handle the object
  68  */
  69 bool_t
  70 xdr_reference(XDR *xdrs, caddr_t *pp, u_int size, xdrproc_t proc)
  71 {
  72         caddr_t loc = *pp;
  73         bool_t stat;
  74
  75         if (loc == NULL)
  76                 switch (xdrs->x_op) {
  77                 case XDR_FREE:
  78                         return (TRUE);
  79
  80                 case XDR_DECODE:
  81                         *pp = loc = (caddr_t) mem_alloc(size);
  82                         if (loc == NULL) {
  83                                 warnx("xdr_reference: out of memory");
  84                                 return (FALSE);
  85                         }
  86                         memset(loc, 0, size);
  87                         break;
  88
  89                 case XDR_ENCODE:
  90                         break;
  91                 }
  92
  93         stat = (*proc)(xdrs, loc);
  94
  95         if (xdrs->x_op == XDR_FREE) {
  96                 mem_free(loc, size);
  97                 *pp = NULL;
  98         }
  99         return (stat);
 100 }
 101
 102
 103 /*
 104  * xdr_pointer():
 105  *
 106  * XDR a pointer to a possibly recursive data structure. This
 107  * differs with xdr_reference in that it can serialize/deserialiaze
 108  * trees correctly.
 109  *
 110  *  What's sent is actually a union:
 111  *
 112  *  union object_pointer switch (boolean b) {
 113  *  case TRUE: object_data data;
 114  *  case FALSE: void nothing;
 115  *  }
 116  *
 117  * > objpp: Pointer to the pointer to the object.
 118  * > obj_size: size of the object.
 119  * > xdr_obj: routine to XDR an object.
 120  *
 121  */
 122 bool_t
 123 xdr_pointer(XDR *xdrs, char **objpp, u_int obj_size, xdrproc_t xdr_obj)
 124 {
 125         bool_t more_data;
 126
 127         more_data = (*objpp != NULL);
 128         if (! xdr_bool(xdrs,&more_data)) {
 129                 return (FALSE);
 130         }
 131         if (! more_data) {
 132                 *objpp = NULL;
 133                 return (TRUE);
 134         }
 135         return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
 136 }