open.c revision 1.4.2.2
1 1.4.2.2 pk /*- 2 1.4.2.2 pk * Copyright (c) 1993 3 1.4.2.2 pk * The Regents of the University of California. All rights reserved. 4 1.4.2.2 pk * 5 1.4.2.2 pk * This code is derived from software contributed to Berkeley by 6 1.4.2.2 pk * The Mach Operating System project at Carnegie-Mellon University. 7 1.4.2.2 pk * 8 1.4.2.2 pk * Redistribution and use in source and binary forms, with or without 9 1.4.2.2 pk * modification, are permitted provided that the following conditions 10 1.4.2.2 pk * are met: 11 1.4.2.2 pk * 1. Redistributions of source code must retain the above copyright 12 1.4.2.2 pk * notice, this list of conditions and the following disclaimer. 13 1.4.2.2 pk * 2. Redistributions in binary form must reproduce the above copyright 14 1.4.2.2 pk * notice, this list of conditions and the following disclaimer in the 15 1.4.2.2 pk * documentation and/or other materials provided with the distribution. 16 1.4.2.2 pk * 3. All advertising materials mentioning features or use of this software 17 1.4.2.2 pk * must display the following acknowledgement: 18 1.4.2.2 pk * This product includes software developed by the University of 19 1.4.2.2 pk * California, Berkeley and its contributors. 20 1.4.2.2 pk * 4. Neither the name of the University nor the names of its contributors 21 1.4.2.2 pk * may be used to endorse or promote products derived from this software 22 1.4.2.2 pk * without specific prior written permission. 23 1.4.2.2 pk * 24 1.4.2.2 pk * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 1.4.2.2 pk * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 1.4.2.2 pk * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 1.4.2.2 pk * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 1.4.2.2 pk * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 1.4.2.2 pk * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 1.4.2.2 pk * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 1.4.2.2 pk * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 1.4.2.2 pk * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 1.4.2.2 pk * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 1.4.2.2 pk * SUCH DAMAGE. 35 1.4.2.2 pk * 36 1.4.2.2 pk * From: @(#)open.c 8.1 (Berkeley) 6/11/93 37 1.4.2.2 pk * 38 1.4.2.2 pk * 39 1.4.2.2 pk * Copyright (c) 1989, 1990, 1991 Carnegie Mellon University 40 1.4.2.2 pk * All Rights Reserved. 41 1.4.2.2 pk * 42 1.4.2.2 pk * Author: Alessandro Forin 43 1.4.2.2 pk * 44 1.4.2.2 pk * Permission to use, copy, modify and distribute this software and its 45 1.4.2.2 pk * documentation is hereby granted, provided that both the copyright 46 1.4.2.2 pk * notice and this permission notice appear in all copies of the 47 1.4.2.2 pk * software, derivative works or modified versions, and any portions 48 1.4.2.2 pk * thereof, and that both notices appear in supporting documentation. 49 1.4.2.2 pk * 50 1.4.2.2 pk * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 51 1.4.2.2 pk * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 52 1.4.2.2 pk * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 53 1.4.2.2 pk * 54 1.4.2.2 pk * Carnegie Mellon requests users of this software to return to 55 1.4.2.2 pk * 56 1.4.2.2 pk * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU 57 1.4.2.2 pk * School of Computer Science 58 1.4.2.2 pk * Carnegie Mellon University 59 1.4.2.2 pk * Pittsburgh PA 15213-3890 60 1.4.2.2 pk * 61 1.4.2.2 pk * any improvements or extensions that they make and grant Carnegie the 62 1.4.2.2 pk * rights to redistribute these changes. 63 1.4.2.2 pk * 64 1.4.2.2 pk * $Id: open.c,v 1.4.2.2 1994/07/18 18:41:13 pk Exp $ 65 1.4.2.2 pk */ 66 1.4.2.2 pk 67 1.4.2.2 pk #include "stand.h" 68 1.4.2.2 pk struct open_file files[SOPEN_MAX]; 69 1.4.2.2 pk 70 1.4.2.2 pk /* 71 1.4.2.2 pk * File primitives proper 72 1.4.2.2 pk */ 73 1.4.2.2 pk 74 1.4.2.2 pk int 75 1.4.2.2 pk open(fname, mode) 76 1.4.2.2 pk char *fname; 77 1.4.2.2 pk int mode; 78 1.4.2.2 pk { 79 1.4.2.2 pk register struct open_file *f; 80 1.4.2.2 pk register int fd, i, error; 81 1.4.2.2 pk char *file; 82 1.4.2.2 pk 83 1.4.2.2 pk /* find a free file descriptor */ 84 1.4.2.2 pk for (fd = 0, f = files; fd < SOPEN_MAX; fd++, f++) 85 1.4.2.2 pk if (f->f_flags == 0) 86 1.4.2.2 pk goto fnd; 87 1.4.2.2 pk errno = EMFILE; 88 1.4.2.2 pk return (-1); 89 1.4.2.2 pk fnd: 90 1.4.2.2 pk /* 91 1.4.2.2 pk * Try to open the device. 92 1.4.2.2 pk * Convert open mode (0,1,2) to F_READ, F_WRITE. 93 1.4.2.2 pk */ 94 1.4.2.2 pk f->f_flags = mode + 1; 95 1.4.2.2 pk f->f_dev = (struct devsw *)0; 96 1.4.2.2 pk file = (char *)0; 97 1.4.2.2 pk error = devopen(f, fname, &file); 98 1.4.2.2 pk if (error || 99 1.4.2.2 pk (((f->f_flags & F_NODEV) == 0) && f->f_dev == (struct devsw *)0)) 100 1.4.2.2 pk goto err; 101 1.4.2.2 pk 102 1.4.2.2 pk /* see if we opened a raw device; otherwise, 'file' is the file name. */ 103 1.4.2.2 pk if (file == (char *)0) { 104 1.4.2.2 pk f->f_flags |= F_RAW; 105 1.4.2.2 pk return (0); 106 1.4.2.2 pk } 107 1.4.2.2 pk 108 1.4.2.2 pk /* pass file name to the different filesystem open routines */ 109 1.4.2.2 pk for (i = 0; i < nfsys; i++) { 110 1.4.2.2 pk /* convert mode (0,1,2) to FREAD, FWRITE. */ 111 1.4.2.2 pk error = (file_system[i].open)(file, f); 112 1.4.2.2 pk if (error == 0) { 113 1.4.2.2 pk f->f_ops = &file_system[i]; 114 1.4.2.2 pk return (fd); 115 1.4.2.2 pk } 116 1.4.2.2 pk } 117 1.4.2.2 pk if (!error) 118 1.4.2.2 pk error = ENOENT; 119 1.4.2.2 pk 120 1.4.2.2 pk err: 121 1.4.2.2 pk f->f_flags = 0; 122 1.4.2.2 pk errno = error; 123 1.4.2.2 pk return (-1); 124 1.4.2.2 pk } 125 1.4.2.2 pk 126 1.4.2.2 pk /* 127 1.4.2.2 pk * Null filesystem 128 1.4.2.2 pk */ 129 1.4.2.2 pk int null_open (char *path, struct open_file *f) 130 1.4.2.2 pk { 131 1.4.2.2 pk errno = EIO; 132 1.4.2.2 pk return -1; 133 1.4.2.2 pk } 134 1.4.2.2 pk 135 1.4.2.2 pk int null_close(struct open_file *f) 136 1.4.2.2 pk { 137 1.4.2.2 pk return 0; 138 1.4.2.2 pk } 139 1.4.2.2 pk 140 1.4.2.2 pk int null_read (struct open_file *f, char *buf, u_int size, u_int *resid) 141 1.4.2.2 pk { 142 1.4.2.2 pk errno = EIO; 143 1.4.2.2 pk return -1; 144 1.4.2.2 pk } 145 1.4.2.2 pk 146 1.4.2.2 pk int null_write (struct open_file *f, char *buf, u_int size, u_int *resid) 147 1.4.2.2 pk { 148 1.4.2.2 pk errno = EIO; 149 1.4.2.2 pk return -1; 150 1.4.2.2 pk } 151 1.4.2.2 pk 152 1.4.2.2 pk off_t null_seek (struct open_file *f, off_t offset, int where) 153 1.4.2.2 pk { 154 1.4.2.2 pk errno = EIO; 155 1.4.2.2 pk return -1; 156 1.4.2.2 pk } 157 1.4.2.2 pk 158 1.4.2.2 pk int null_stat (struct open_file *f, struct stat *sb) 159 1.4.2.2 pk { 160 1.4.2.2 pk errno = EIO; 161 1.4.2.2 pk return -1; 162 1.4.2.2 pk } 163 1.4.2.2 pk 164
Indexes created Tue Sep 30 20:09:53 GMT 2025