1 /** $MirOS: src/sys/lib/libsa/open.c,v 1.5 2010/01/10 19:21:38 tg Exp $ */
2 /* $OpenBSD: open.c,v 1.10 2003/08/11 06:23:09 deraadt Exp $ */
3 /* $NetBSD: open.c,v 1.12 1996/09/30 16:01:21 ws Exp $ */
4
5 /*-
6 * Copyright (c) 1993
7 * The Regents of the University of California. All rights reserved.
8 *
9 * This code is derived from software contributed to Berkeley by
10 * The Mach Operating System project at Carnegie-Mellon University.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * @(#)open.c 8.1 (Berkeley) 6/11/93
37 *
38 *
39 * Copyright (c) 1989, 1990, 1991 Carnegie Mellon University
40 * All Rights Reserved.
41 *
42 * Author: Alessandro Forin
43 *
44 * Permission to use, copy, modify and distribute this software and its
45 * documentation is hereby granted, provided that both the copyright
46 * notice and this permission notice appear in all copies of the
47 * software, derivative works or modified versions, and any portions
48 * thereof, and that both notices appear in supporting documentation.
49 *
50 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
51 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
52 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
53 *
54 * Carnegie Mellon requests users of this software to return to
55 *
56 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
57 * School of Computer Science
58 * Carnegie Mellon University
59 * Pittsburgh PA 15213-3890
60 *
61 * any improvements or extensions that they make and grant Carnegie the
62 * rights to redistribute these changes.
63 */
64
65 #include "stand.h"
66
67 extern int debug;
68
69 struct open_file files[SOPEN_MAX];
70
71 const char ustar_magic_version[8] = { 'u', 's', 't', 'a', 'r', 0, '0', '0' };
72
73 /*
74 * File primitives proper
75 */
76
77 int
78 #ifndef __INTERNAL_LIBSA_CREAD
open(const char * fname,int mode)79 open(const char *fname, int mode)
80 #else
81 oopen(const char *fname, int mode)
82 #endif
83 {
84 struct open_file *f;
85 int fd, i, error;
86 char *file;
87
88 #ifdef DEBUG
89 if (debug)
90 printf("oopen(%s):", fname);
91 #endif
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 #ifdef DEBUG
99 if (debug)
100 printf("EMFILE\n");
101 #endif
102 return (-1);
103 fnd:
104 /*
105 * Try to open the device.
106 * Convert open mode (0,1,2) to F_READ, F_WRITE.
107 */
108 f->f_flags = mode + 1;
109 f->f_dev = (struct devsw *)0;
110 f->f_ops = (struct fs_ops *)0;
111 file = (char *)0;
112 #ifdef DEBUG
113 if (debug)
114 putchar('<');
115 #endif
116 error = devopen(f, fname, &file);
117 #ifdef DEBUG
118 if (debug)
119 putchar('>');
120 #endif
121 if (error ||
122 (((f->f_flags & F_NODEV) == 0) && f->f_dev == (struct devsw *)0))
123 goto err;
124
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 #ifdef DEBUG
129 if (debug)
130 printf("=raw(%d)\n", fd);
131 #endif
132 return (fd);
133 }
134
135 /* allow f->f_ops to be set by devopen routine */
136 if (f->f_ops != NULL) {
137 #ifdef DEBUG
138 if (debug)
139 printf("=>dev:ops(%s)", f->f_ops->name);
140 #endif
141 error = f->f_ops->open(file, f);
142 if (error == 0) {
143 #ifdef DEBUG
144 if (debug)
145 printf("=>ok(%d)\n", fd);
146 #endif
147 return (fd);
148 } else if (error == ENOENT || error == ENOTDIR)
149 goto no_match;
150 }
151
152 /* pass file name to the different filesystem open routines */
153 for (i = 0; i < nfsys; i++) {
154 #ifdef DEBUG
155 if (debug)
156 printf(" try(%s)", file_system[i].name);
157 #endif
158 /* convert mode (0,1,2) to FREAD, FWRITE. */
159 error = (file_system[i].open)(file, f);
160 if (error == 0) {
161 f->f_ops = &file_system[i];
162 #ifdef DEBUG
163 if (debug)
164 printf("=>ok(%d)\n", fd);
165 #endif
166 return (fd);
167 }
168 #ifdef DEBUG
169 if (debug)
170 printf("=>err(%u)", error);
171 #endif
172 if (error == ENOENT || error == ENOTDIR)
173 break;
174 }
175 no_match:
176 #ifdef DEBUG
177 if (debug)
178 printf(" no match");
179 #endif
180 if (!error)
181 error = ENOENT;
182
183 f->f_dev->dv_close(f);
184 err:
185 f->f_ops = NULL;
186 f->f_flags = 0;
187 #ifdef DEBUG
188 if (debug)
189 printf("=>err(%u)\n", error);
190 #endif
191 errno = error;
192 return (-1);
193 }
194