xref: /netbsd-src/sys/lib/libsa/open.c (revision 27578b9aac214cc7796ead81dcc5427e79d5f2a0)
1 /*	$NetBSD: open.c,v 1.20 2000/03/30 12:19:48 augustss 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 struct open_file files[SOPEN_MAX];
70 
71 /*
72  *	File primitives proper
73  */
74 
75 #ifdef HELLO_CTAGS
76 oopen(){}
77 #endif
78 
79 int
80 #ifndef __INTERNAL_LIBSA_CREAD
81 open(fname, mode)
82 #else
83 oopen(fname, mode)
84 #endif
85 	const char *fname;
86 	int mode;
87 {
88 	struct open_file *f;
89 	int fd, error;
90 #if !defined(LIBSA_SINGLE_FILESYSTEM)
91 	int i, besterror;
92 #endif
93 	char *file;
94 
95 	/* find a free file descriptor */
96 	for (fd = 0, f = files; fd < SOPEN_MAX; fd++, f++)
97 		if (f->f_flags == 0)
98 			goto fnd;
99 	errno = EMFILE;
100 	return (-1);
101 fnd:
102 	/*
103 	 * Try to open the device.
104 	 * Convert open mode (0,1,2) to F_READ, F_WRITE.
105 	 */
106 	f->f_flags = mode + 1;
107 #if !defined(LIBSA_SINGLE_DEVICE)
108 	f->f_dev = (struct devsw *)0;
109 #endif
110 #if !defined(LIBSA_SINGLE_FILESYSTEM)
111 	f->f_ops = (struct fs_ops *)0;
112 #endif
113 #if !defined(LIBSA_NO_RAW_ACCESS)
114 	f->f_offset = 0;
115 #endif
116 	file = (char *)0;
117 	error = devopen(f, fname, &file);
118 	if (error
119 #if !defined(LIBSA_SINGLE_DEVICE)
120 	    || (((f->f_flags & F_NODEV) == 0) &&
121 		f->f_dev == (struct devsw *)0)
122 #endif
123 	    )
124 		goto err;
125 
126 #if !defined(LIBSA_NO_RAW_ACCESS)
127 	/* see if we opened a raw device; otherwise, 'file' is the file name. */
128 	if (file == (char *)0 || *file == '\0') {
129 		f->f_flags |= F_RAW;
130 		return (fd);
131 	}
132 #endif
133 
134 	/* pass file name to the different filesystem open routines */
135 #if !defined(LIBSA_SINGLE_FILESYSTEM)
136 	besterror = ENOENT;
137 	for (i = 0; i < nfsys; i++) {
138 		error = FS_OPEN(&file_system[i])(file, f);
139 		if (error == 0) {
140 			f->f_ops = &file_system[i];
141 			return (fd);
142 		}
143 		if (error != EINVAL)
144 			besterror = error;
145 	}
146 	error = besterror;
147 #else
148 	error = FS_OPEN(&file_system[i])(file, f);
149 	if (error == 0)
150 		return (fd);
151 	else if (error == EINVAL)
152 		error = ENOENT;
153 #endif
154 
155 	if ((f->f_flags & F_NODEV) == 0)
156 #if !defined(LIBSA_SINGLE_DEVICE)
157 		if (DEV_CLOSE(f->f_dev) != NULL)
158 #endif
159 			(void)DEV_CLOSE(f->f_dev)(f);
160 err:
161 	f->f_flags = 0;
162 	errno = error;
163 	return (-1);
164 }
165