xdr_array.c revision 1219:f89f56c2d9ac 
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22
23/*
24 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
25 * Use is subject to license terms.
26 */
27
28/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
29/* All Rights Reserved */
30/*
31 * Portions of this source code were derived from Berkeley
32 * 4.3 BSD under license from the Regents of the University of
33 * California.
34 */
35
36#pragma ident	"%Z%%M%	%I%	%E% SMI"
37
38/*
39 * Generic XDR routines impelmentation.
40 *
41 * These are the "non-trivial" xdr primitives used to serialize and de-serialize
42 * arrays.  See xdr.h for more info on the interface to xdr.
43 */
44
45#include "mt.h"
46#include <sys/types.h>
47#include <syslog.h>
48#include <stdio.h>
49#include <stdlib.h>
50
51#include <rpc/types.h>
52#include <rpc/xdr.h>
53#include <memory.h>
54
55#define	LASTUNSIGNED	((uint_t)0-1)
56
57char mem_err_msg_arr[] = "xdr_array: out of memory";
58
59/*
60 * XDR an array of arbitrary elements
61 * *addrp is a pointer to the array, *sizep is the number of elements.
62 * If *addrp is NULL (*sizep * elsize) bytes are allocated.
63 * elsize is the size (in bytes) of each element, and elproc is the
64 * xdr procedure to call to handle each element of the array.
65 */
66bool_t
67xdr_array(XDR *xdrs, caddr_t *addrp, uint_t *sizep, const uint_t maxsize,
68	const uint_t elsize, const xdrproc_t elproc)
69{
70	uint_t i;
71	caddr_t target = *addrp;
72	uint_t c;  /* the actual element count */
73	bool_t stat = TRUE;
74	uint_t nodesize;
75
76	/* like strings, arrays are really counted arrays */
77	if (!xdr_u_int(xdrs, sizep))
78		return (FALSE);
79	c = *sizep;
80	if ((c > maxsize || LASTUNSIGNED / elsize < c) &&
81	    xdrs->x_op != XDR_FREE)
82		return (FALSE);
83	nodesize = c * elsize;
84
85	/*
86	 * if we are deserializing, we may need to allocate an array.
87	 * We also save time by checking for a null array if we are freeing.
88	 */
89	if (target == NULL)
90		switch (xdrs->x_op) {
91		case XDR_DECODE:
92			if (c == 0)
93				return (TRUE);
94			*addrp = target = malloc(nodesize);
95			if (target == NULL) {
96				(void) syslog(LOG_ERR, mem_err_msg_arr);
97				return (FALSE);
98			}
99			(void) memset(target, 0, nodesize);
100			break;
101
102		case XDR_FREE:
103			return (TRUE);
104	}
105
106	/*
107	 * now we xdr each element of array
108	 */
109	for (i = 0; (i < c) && stat; i++) {
110		stat = (*elproc)(xdrs, target);
111		target += elsize;
112	}
113
114	/*
115	 * the array may need freeing
116	 */
117	if (xdrs->x_op == XDR_FREE) {
118		free(*addrp);
119		*addrp = NULL;
120	}
121	return (stat);
122}
123
124/*
125 * xdr_vector():
126 *
127 * XDR a fixed length array. Unlike variable-length arrays,
128 * the storage of fixed length arrays is static and unfreeable.
129 * > basep: base of the array
130 * > size: size of the array
131 * > elemsize: size of each element
132 * > xdr_elem: routine to XDR each element
133 */
134bool_t
135xdr_vector(XDR *xdrs, char *basep, const uint_t nelem,
136	const uint_t elemsize, const xdrproc_t xdr_elem)
137{
138	uint_t i;
139	char *elptr;
140
141	elptr = basep;
142	for (i = 0; i < nelem; i++) {
143		if (!(*xdr_elem)(xdrs, elptr, LASTUNSIGNED))
144			return (FALSE);
145		elptr += elemsize;
146	}
147	return (TRUE);
148}
149