1 /* $OpenBSD: open.c,v 1.10 2003/08/11 06:23:09 deraadt Exp $ */
2 /* $NetBSD: open.c,v 1.12 1996/09/30 16:01:21 ws Exp $ */
3
4 /*-
5 * Copyright (c) 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * The Mach Operating System project at Carnegie-Mellon University.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * @(#)open.c 8.1 (Berkeley) 6/11/93
36 *
37 *
38 * Copyright (c) 1989, 1990, 1991 Carnegie Mellon University
39 * All Rights Reserved.
40 *
41 * Author: Alessandro Forin
42 *
43 * Permission to use, copy, modify and distribute this software and its
44 * documentation is hereby granted, provided that both the copyright
45 * notice and this permission notice appear in all copies of the
46 * software, derivative works or modified versions, and any portions
47 * thereof, and that both notices appear in supporting documentation.
48 *
49 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
50 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
51 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
52 *
53 * Carnegie Mellon requests users of this software to return to
54 *
55 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
56 * School of Computer Science
57 * Carnegie Mellon University
58 * Pittsburgh PA 15213-3890
59 *
60 * any improvements or extensions that they make and grant Carnegie the
61 * rights to redistribute these changes.
62 */
63
64 #include "stand.h"
65
66 struct open_file files[SOPEN_MAX];
67
68 /*
69 * File primitives proper
70 */
71
72 int
73 #ifndef __INTERNAL_LIBSA_CREAD
74 open(const char *fname, int mode)
75 #else
76 oopen(const char *fname, int mode)
77 #endif
78 {
79 struct open_file *f;
80 int fd, i, error;
81 char *file;
82
83 /* find a free file descriptor */
84 for (fd = 0, f = files; fd < SOPEN_MAX; fd++, f++)
85 if (f->f_flags == 0)
86 goto fnd;
87 errno = EMFILE;
88 return (-1);
89 fnd:
90 /*
91 * Try to open the device.
92 * Convert open mode (0,1,2) to F_READ, F_WRITE.
93 */
94 f->f_flags = mode + 1;
95 f->f_dev = (struct devsw *)0;
96 f->f_ops = (struct fs_ops *)0;
97 file = (char *)0;
98 error = devopen(f, fname, &file);
99 if (error ||
100 (((f->f_flags & F_NODEV) == 0) && f->f_dev == (struct devsw *)0))
101 goto err;
102
103 /* see if we opened a raw device; otherwise, 'file' is the file name. */
104 if (file == (char *)0 || *file == '\0') {
105 f->f_flags |= F_RAW;
106 return (fd);
107 }
108
109 /* pass file name to the different filesystem open routines */
110 for (i = 0; i < nfsys; i++) {
111 /* convert mode (0,1,2) to FREAD, FWRITE. */
112 error = (file_system[i].open)(file, f);
113 if (error == 0) {
114 f->f_ops = &file_system[i];
115 return (fd);
116 }
117 if (error == ENOENT || error == ENOTDIR)
118 break;
119 }
120 if (!error)
121 error = ENOENT;
122
123 f->f_dev->dv_close(f);
124 err:
125 f->f_flags = 0;
126 errno = error;
127 return (-1);
128 }