fattach.c revision 5006:304eb1332eef 
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 2007 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26#pragma ident	"%Z%%M%	%I%	%E% SMI"
27
28/*	Copyright (c) 1988 AT&T	*/
29/*	  All Rights Reserved  	*/
30
31
32/*
33 * Attach a STREAMS or door based file descriptor to an object in the file
34 * system name space.
35 */
36#pragma weak fattach = _fattach
37#include "synonyms.h"
38#include <sys/types.h>
39#include <errno.h>
40#include <stdio.h>
41#include <stropts.h>
42#include <sys/door.h>
43#include <sys/fs/namenode.h>
44#include <sys/mount.h>
45#include <unistd.h>
46#include <string.h>
47#include "libc.h"
48
49int
50fattach(int fildes, const char *path)
51{
52	struct namefd  namefdp;
53	struct door_info dinfo;
54	int	s;
55	char buf[MAXPATHLEN];
56
57	/* Only STREAMS and doors allowed to be mounted */
58	if ((s = isastream(fildes)) == 1 || __door_info(fildes, &dinfo) == 0) {
59		namefdp.fd = fildes;
60		if (path == NULL || *path == '\0') {
61			errno = ENOENT;
62			return (-1);
63		} else if (*path != '/') {
64			/*
65			 * The mount point must be an absolute path.
66			 */
67			if (getcwd(buf, sizeof (buf)) == NULL) {
68				/* errno already set */
69				return (-1);
70			}
71			/*
72			 * The kernel will truncate the path if it would have
73			 * turned into something more than MAXPATHLEN bytes.
74			 * So we do the same here.
75			 */
76			if (strlcat(buf, "/",  sizeof (buf)) >= sizeof (buf) ||
77			    strlcat(buf, path, sizeof (buf)) >= sizeof (buf)) {
78				errno = ENAMETOOLONG;
79				return (-1);
80			}
81			path = buf;
82		}
83		return (mount((char *)NULL, path, MS_DATA|MS_NOMNTTAB,
84		    (const char *)"namefs", (char *)&namefdp,
85		    sizeof (struct namefd), NULL, 0));
86	} else if (s == 0) {
87		/* Not a STREAM */
88		errno = EINVAL;
89		return (-1);
90	} else {
91		/* errno already set */
92		return (-1);
93	}
94}
95