xref: /netbsd-src/sys/lib/libsa/open.c (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1 /*	$NetBSD: open.c,v 1.21 2002/02/23 05:44:24 thorpej 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@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 	else 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 err:
159 	f->f_flags = 0;
160 	errno = error;
161 	return (-1);
162 }
163