open.c revision 1.22 1 /* $NetBSD: open.c,v 1.22 2003/02/01 14:54:22 dsl Exp $ */
2
3 /*-
4 * Copyright (c) 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * The Mach Operating System project at Carnegie-Mellon University.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)open.c 8.1 (Berkeley) 6/11/93
39 *
40 *
41 * Copyright (c) 1989, 1990, 1991 Carnegie Mellon University
42 * All Rights Reserved.
43 *
44 * Author: Alessandro Forin
45 *
46 * Permission to use, copy, modify and distribute this software and its
47 * documentation is hereby granted, provided that both the copyright
48 * notice and this permission notice appear in all copies of the
49 * software, derivative works or modified versions, and any portions
50 * thereof, and that both notices appear in supporting documentation.
51 *
52 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
53 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
54 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
55 *
56 * Carnegie Mellon requests users of this software to return to
57 *
58 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU
59 * School of Computer Science
60 * Carnegie Mellon University
61 * Pittsburgh PA 15213-3890
62 *
63 * any improvements or extensions that they make and grant Carnegie the
64 * rights to redistribute these changes.
65 */
66
67 #include "stand.h"
68
69 /*
70 * File primitives proper
71 */
72
73 #ifdef HELLO_CTAGS
74 oopen(){}
75 #endif
76
77 int
78 #ifndef __INTERNAL_LIBSA_CREAD
79 open(fname, mode)
80 #else
81 oopen(fname, mode)
82 #endif
83 const char *fname;
84 int mode;
85 {
86 struct open_file *f;
87 int fd, error;
88 #if !defined(LIBSA_SINGLE_FILESYSTEM)
89 int i, besterror;
90 #endif
91 char *file;
92
93 /* find a free file descriptor */
94 for (fd = 0, f = files; fd < SOPEN_MAX; fd++, f++)
95 if (f->f_flags == 0)
96 goto fnd;
97 errno = EMFILE;
98 return (-1);
99 fnd:
100 /*
101 * Try to open the device.
102 * Convert open mode (0,1,2) to F_READ, F_WRITE.
103 */
104 f->f_flags = mode + 1;
105 #if !defined(LIBSA_SINGLE_DEVICE)
106 f->f_dev = (struct devsw *)0;
107 #endif
108 #if !defined(LIBSA_SINGLE_FILESYSTEM)
109 f->f_ops = (struct fs_ops *)0;
110 #endif
111 #if !defined(LIBSA_NO_RAW_ACCESS)
112 f->f_offset = 0;
113 #endif
114 file = (char *)0;
115 error = devopen(f, fname, &file);
116 if (error
117 #if !defined(LIBSA_SINGLE_DEVICE)
118 || (((f->f_flags & F_NODEV) == 0) &&
119 f->f_dev == (struct devsw *)0)
120 #endif
121 )
122 goto err;
123
124 #if !defined(LIBSA_NO_RAW_ACCESS)
125 /* see if we opened a raw device; otherwise, 'file' is the file name. */
126 if (file == (char *)0 || *file == '\0') {
127 f->f_flags |= F_RAW;
128 return (fd);
129 }
130 #endif
131
132 /* pass file name to the different filesystem open routines */
133 #if !defined(LIBSA_SINGLE_FILESYSTEM)
134 besterror = ENOENT;
135 for (i = 0; i < nfsys; i++) {
136 error = FS_OPEN(&file_system[i])(file, f);
137 if (error == 0) {
138 f->f_ops = &file_system[i];
139 return (fd);
140 }
141 if (error != EINVAL)
142 besterror = error;
143 }
144 error = besterror;
145 #else
146 error = FS_OPEN(&file_system[i])(file, f);
147 if (error == 0)
148 return (fd);
149 if (error == EINVAL)
150 error = ENOENT;
151 #endif
152
153 if ((f->f_flags & F_NODEV) == 0) {
154 #if !defined(LIBSA_SINGLE_DEVICE)
155 if (DEV_CLOSE(f->f_dev) != NULL)
156 #endif
157 (void)DEV_CLOSE(f->f_dev)(f);
158 }
159 err:
160 f->f_flags = 0;
161 errno = error;
162 return (-1);
163 }
164