lib/libc/rpc/xdr_reference.c

   1 /*      $NetBSD: xdr_reference.c,v 1.18 2013/03/11 20:19:30 tron Exp $  */
   2
   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
  34 #include <sys/cdefs.h>
  35 #if defined(LIBC_SCCS) && !defined(lint)
  36 #if 0
  37 static char *sccsid = "@(#)xdr_reference.c 1.11 87/08/11 SMI";
  38 static char *sccsid = "@(#)xdr_reference.c      2.1 88/07/29 4.0 RPCSRC";
  39 #else
  40 __RCSID("$NetBSD: xdr_reference.c,v 1.18 2013/03/11 20:19:30 tron Exp $");
  41 #endif
  42 #endif
  43
  44 /*
  45  * xdr_reference.c, Generic XDR routines implementation.
  46  *
  47  * Copyright (C) 1987, Sun Microsystems, Inc.
  48  *
  49  * These are the "non-trivial" xdr primitives used to serialize and de-serialize
  50  * "pointers".  See xdr.h for more info on the interface to xdr.
  51  */
  52
  53 #include "namespace.h"
  54
  55 #include <err.h>
  56 #include <stdio.h>
  57 #include <stdlib.h>
  58 #include <string.h>
  59
  60 #include <rpc/types.h>
  61 #include <rpc/xdr.h>
  62
  63 #ifdef __weak_alias
  64 __weak_alias(xdr_pointer,_xdr_pointer)
  65 __weak_alias(xdr_reference,_xdr_reference)
  66 #endif
  67
  68 /*
  69  * XDR an indirect pointer
  70  * xdr_reference is for recursively translating a structure that is
  71  * referenced by a pointer inside the structure that is currently being
  72  * translated.  pp references a pointer to storage. If *pp is null
  73  * the  necessary storage is allocated.
  74  * size is the sizeof the referneced structure.
  75  * proc is the routine to handle the referenced structure.
  76  */
  77 bool_t
  78 xdr_reference(XDR *xdrs, caddr_t *pp, u_int size, xdrproc_t proc)
  79 {
  80         caddr_t loc = *pp;
  81         bool_t stat;
  82
  83         if (loc == NULL)
  84                 switch (xdrs->x_op) {
  85                 case XDR_FREE:
  86                         return (TRUE);
  87
  88                 case XDR_DECODE:
  89                         *pp = loc = mem_alloc(size);
  90                         if (loc == NULL) {
  91                                 warn("%s: out of memory", __func__);
  92                                 return (FALSE);
  93                         }
  94                         memset(loc, 0, size);
  95                         break;
  96
  97                 case XDR_ENCODE:
  98                         break;
  99                 }
 100
 101         stat = (*proc)(xdrs, loc);
 102
 103         if (xdrs->x_op == XDR_FREE) {
 104                 mem_free(loc, size);
 105                 *pp = NULL;
 106         }
 107         return (stat);
 108 }
 109
 110
 111 /*
 112  * xdr_pointer():
 113  *
 114  * XDR a pointer to a possibly recursive data structure. This
 115  * differs with xdr_reference in that it can serialize/deserialiaze
 116  * trees correctly.
 117  *
 118  *  What's sent is actually a union:
 119  *
 120  *  union object_pointer switch (boolean b) {
 121  *  case TRUE: object_data data;
 122  *  case FALSE: void nothing;
 123  *  }
 124  *
 125  * > objpp: Pointer to the pointer to the object.
 126  * > obj_size: size of the object.
 127  * > xdr_obj: routine to XDR an object.
 128  *
 129  */
 130 bool_t
 131 xdr_pointer(XDR *xdrs, char **objpp, u_int obj_size, xdrproc_t xdr_obj)
 132 {
 133
 134         bool_t more_data;
 135
 136         more_data = (*objpp != NULL);
 137         if (! xdr_bool(xdrs,&more_data)) {
 138                 return (FALSE);
 139         }
 140         if (! more_data) {
 141                 *objpp = NULL;
 142                 return (TRUE);
 143         }
 144         return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
 145 }