xref: /openbsd/sys/arch/amd64/stand/pxeboot/open.c (revision 404b540a)
1 /*	$OpenBSD: open.c,v 1.1 2004/03/21 21:37:41 tom 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 <lib/libsa/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 	/* Allow f->f_ops to be set by devopen routine. */
110 	if (f->f_ops != NULL) {
111 		error = f->f_ops->open(file, f);
112 		if (error == 0)
113 			return fd;
114 	}
115 	else {
116 		/* pass file name to the different filesystem open routines */
117 		for (i = 0; i < nfsys; i++) {
118 			/* convert mode (0,1,2) to FREAD, FWRITE. */
119 			error = (file_system[i].open)(file, f);
120 			if (error == 0) {
121 				f->f_ops = &file_system[i];
122 				return (fd);
123 			}
124 			if (error == ENOENT || error == ENOTDIR)
125 				break;
126 		}
127 	}
128 	if (error == 0)
129 		error = ENOENT;
130 
131 	f->f_dev->dv_close(f);
132 err:
133 	f->f_flags = 0;
134 	errno = error;
135 	return -1;
136 }
137