xref: /titanic_41/usr/src/uts/common/rpc/xdr_array.c (revision 80e2ca8596e3435bc3b76f3c597833ea0a87f85e)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
27 /*	  All Rights Reserved  	*/
28 
29 /*
30  * Portions of this source code were derived from Berkeley 4.3 BSD
31  * under license from the Regents of the University of California.
32  */
33 
34 /*
35  * xdr_array.c, Generic XDR routines impelmentation.
36  * These are the "non-trivial" xdr primitives used to serialize and de-serialize
37  * arrays.  See xdr.h for more info on the interface to xdr.
38  */
39 
40 #include <sys/param.h>
41 #include <sys/cmn_err.h>
42 #include <sys/types.h>
43 #include <sys/systm.h>
44 
45 #include <rpc/types.h>
46 #include <rpc/xdr.h>
47 
48 #define	LASTUNSIGNED	((uint_t)0-1)
49 
50 /*
51  * XDR an array of arbitrary elements
52  * *addrp is a pointer to the array, *sizep is the number of elements.
53  * If addrp is NULL (*sizep * elsize) bytes are allocated.
54  * elsize is the size (in bytes) of each element, and elproc is the
55  * xdr procedure to call to handle each element of the array.
56  */
57 bool_t
58 xdr_array(XDR *xdrs, caddr_t *addrp, uint_t *sizep, const uint_t maxsize,
59 	const uint_t elsize, const xdrproc_t elproc)
60 {
61 	uint_t i;
62 	caddr_t target = *addrp;
63 	uint_t c;  /* the actual element count */
64 	bool_t stat = TRUE;
65 	uint_t nodesize;
66 
67 	/* like strings, arrays are really counted arrays */
68 	if (!xdr_u_int(xdrs, sizep)) {
69 		return (FALSE);
70 	}
71 	c = *sizep;
72 	if ((c > maxsize || LASTUNSIGNED / elsize < c) &&
73 	    xdrs->x_op != XDR_FREE) {
74 		return (FALSE);
75 	}
76 	nodesize = c * elsize;
77 
78 	/*
79 	 * if we are deserializing, we may need to allocate an array.
80 	 * We also save time by checking for a null array if we are freeing.
81 	 */
82 	if (target == NULL)
83 		switch (xdrs->x_op) {
84 		case XDR_DECODE:
85 			if (c == 0)
86 				return (TRUE);
87 			*addrp = target = (char *)mem_alloc(nodesize);
88 			bzero(target, nodesize);
89 			break;
90 
91 		case XDR_FREE:
92 			return (TRUE);
93 
94 		case XDR_ENCODE:
95 			break;
96 		}
97 
98 	/*
99 	 * now we xdr each element of array
100 	 */
101 	for (i = 0; (i < c) && stat; i++) {
102 		stat = (*elproc)(xdrs, target, LASTUNSIGNED);
103 		target += elsize;
104 	}
105 
106 	/*
107 	 * the array may need freeing
108 	 */
109 	if (xdrs->x_op == XDR_FREE) {
110 		mem_free(*addrp, nodesize);
111 		*addrp = NULL;
112 	}
113 	return (stat);
114 }
115