Home | History | Annotate | Line # | Download | only in rpc
xdr_reference.c revision 1.17 
      1 /*	$NetBSD: xdr_reference.c,v 1.17 2013/03/04 17:17:57 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 1.17 2013/03/04 17:17:57 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(XDR *xdrs, caddr_t *pp, u_int size, xdrproc_t proc)
     77 {
     78 	caddr_t loc = *pp;
     79 	bool_t stat;
     80 
     81 	if (loc == NULL)
     82 		switch (xdrs->x_op) {
     83 		case XDR_FREE:
     84 			return (TRUE);
     85 
     86 		case XDR_DECODE:
     87 			*pp = loc = mem_alloc(size);
     88 			if (loc == NULL) {
     89 				warn("%s: out of memory", __func__);
     90 				return (FALSE);
     91 			}
     92 			memset(loc, 0, size);
     93 			break;
     94 
     95 		case XDR_ENCODE:
     96 			break;
     97 		}
     98 
     99 	stat = (*proc)(xdrs, loc);
    100 
    101 	if (xdrs->x_op == XDR_FREE) {
    102 		mem_free(loc, size);
    103 		*pp = NULL;
    104 	}
    105 	return (stat);
    106 }
    107 
    108 
    109 /*
    110  * xdr_pointer():
    111  *
    112  * XDR a pointer to a possibly recursive data structure. This
    113  * differs with xdr_reference in that it can serialize/deserialiaze
    114  * trees correctly.
    115  *
    116  *  What's sent is actually a union:
    117  *
    118  *  union object_pointer switch (boolean b) {
    119  *  case TRUE: object_data data;
    120  *  case FALSE: void nothing;
    121  *  }
    122  *
    123  * > objpp: Pointer to the pointer to the object.
    124  * > obj_size: size of the object.
    125  * > xdr_obj: routine to XDR an object.
    126  *
    127  */
    128 bool_t
    129 xdr_pointer(XDR *xdrs, char **objpp, u_int obj_size, xdrproc_t xdr_obj)
    130 {
    131 
    132 	bool_t more_data;
    133 
    134 	more_data = (*objpp != NULL);
    135 	if (! xdr_bool(xdrs,&more_data)) {
    136 		return (FALSE);
    137 	}
    138 	if (! more_data) {
    139 		*objpp = NULL;
    140 		return (TRUE);
    141 	}
    142 	return (xdr_reference(xdrs,objpp,obj_size,xdr_obj));
    143 }
    144