lib/libc/rpc/xdr_reference.c

   1 /*      $NetBSD: xdr_reference.c,v 1.15 2008/04/25 17:44:44 christos Exp $      */
   2
   3 /*
   4  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   5  * unrestricted use provided that this legend is included on all tape
   6  * media and as a part of the software program in whole or part.  Users
   7  * may copy or modify Sun RPC without charge, but are not authorized
   8  * to license or distribute it to anyone else except as part of a product or
   9  * program developed by the user.
  10  *
  11  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  12  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  13  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  14  *
  15  * Sun RPC is provided with no support and without any obligation on the
  16  * part of Sun Microsystems, Inc. to assist in its use, correction,
  17  * modification or enhancement.
  18  *
  19  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  20  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  21  * OR ANY PART THEREOF.
  22  *
  23  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  24  * or profits or other special, indirect and consequential damages, even if
  25  * Sun has been advised of the possibility of such damages.
  26  *
  27  * Sun Microsystems, Inc.
  28  * 2550 Garcia Avenue
  29  * Mountain View, California  94043
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 #if 0
  35 static char *sccsid = "@(#)xdr_reference.c 1.11 87/08/11 SMI";
  36 static char *sccsid = "@(#)xdr_reference.c      2.1 88/07/29 4.0 RPCSRC";
  37 #else
  38 __RCSID("$NetBSD: xdr_reference.c,v 1.15 2008/04/25 17:44:44 christos Exp $");
  39 #endif
  40 #endif
  41
  42 /*
  43  * xdr_reference.c, Generic XDR routines implementation.
  44  *
  45  * Copyright (C) 1987, Sun Microsystems, Inc.
  46  *
  47  * These are the "non-trivial" xdr primitives used to serialize and de-serialize
  48  * "pointers".  See xdr.h for more info on the interface to xdr.
  49  */
  50
  51 #include "namespace.h"
  52
  53 #include <err.h>
  54 #include <stdio.h>
  55 #include <stdlib.h>
  56 #include <string.h>
  57
  58 #include <rpc/types.h>
  59 #include <rpc/xdr.h>
  60
  61 #ifdef __weak_alias
  62 __weak_alias(xdr_pointer,_xdr_pointer)
  63 __weak_alias(xdr_reference,_xdr_reference)
  64 #endif
  65
  66 /*
  67  * XDR an indirect pointer
  68  * xdr_reference is for recursively translating a structure that is
  69  * referenced by a pointer inside the structure that is currently being
  70  * translated.  pp references a pointer to storage. If *pp is null
  71  * the  necessary storage is allocated.
  72  * size is the sizeof the referneced structure.
  73  * proc is the routine to handle the referenced structure.
  74  */
  75 bool_t
  76 xdr_reference(xdrs, pp, size, proc)
  77         XDR *xdrs;
  78         caddr_t *pp;            /* the pointer to work on */
  79         u_int size;             /* size of the object pointed to */
  80         xdrproc_t proc;         /* xdr routine to handle the object */
  81 {
  82         caddr_t loc = *pp;
  83         bool_t stat;
  84
  85         if (loc == NULL)
  86                 switch (xdrs->x_op) {
  87                 case XDR_FREE:
  88                         return (TRUE);
  89
  90                 case XDR_DECODE:
  91                         *pp = loc = mem_alloc(size);
  92                         if (loc == NULL) {
  93                                 warnx("xdr_reference: out of memory");
  94                                 return (FALSE);
  95                         }
  96                         memset(loc, 0, size);
  97                         break;
  98
  99                 case XDR_ENCODE:
 100                         break;
 101                 }
 102
 103         stat = (*proc)(xdrs, loc);
 104
 105         if (xdrs->x_op == XDR_FREE) {
 106                 mem_free(loc, size);
 107                 *pp = NULL;
 108         }
 109         return (stat);
 110 }
 111
 112
 113 /*
 114  * xdr_pointer():
 115  *
 116  * XDR a pointer to a possibly recursive data structure. This
 117  * differs with xdr_reference in that it can serialize/deserialiaze
 118  * trees correctly.
 119  *
 120  *  What's sent is actually a union:
 121  *
 122  *  union object_pointer switch (boolean b) {
 123  *  case TRUE: object_data data;
 124  *  case FALSE: void nothing;
 125  *  }
 126  *
 127  * > objpp: Pointer to the pointer to the object.
 128  * > obj_size: size of the object.
 129  * > xdr_obj: routine to XDR an object.
 130  *
 131  */
 132 bool_t
 133 xdr_pointer(xdrs,objpp,obj_size,xdr_obj)
 134         XDR *xdrs;
 135         char **objpp;
 136         u_int obj_size;
 137         xdrproc_t xdr_obj;
 138 {
 139
 140         bool_t more_data;
 141
 142         more_data = (*objpp != NULL);
 143         if (! xdr_bool(xdrs,&more_data)) {
 144                 return (FALSE);
 145         }
 146         if (! more_data) {
 147                 *objpp = NULL;
 148                 return (TRUE);
 149         }
 150         return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
 151 }