1 /* $FreeBSD: src/lib/libstand/open.c,v 1.2.6.1 2000/09/10 01:32:06 ps Exp $ */ 2 /* $NetBSD: open.c,v 1.16 1997/01/28 09:41:03 pk 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 "stand.h" 65 66 struct open_file files[SOPEN_MAX]; 67 68 static int 69 o_gethandle(void) 70 { 71 int fd; 72 73 for (fd = 0; fd < SOPEN_MAX; fd++) 74 if (files[fd].f_flags == 0) 75 return(fd); 76 return(-1); 77 } 78 79 static void 80 o_rainit(struct open_file *f) 81 { 82 f->f_rabuf = malloc(SOPEN_RASIZE); 83 f->f_ralen = 0; 84 f->f_raoffset = 0; 85 } 86 87 int 88 open(const char *fname, int mode) 89 { 90 struct open_file *f; 91 int fd, i, error, besterror; 92 const char *file; 93 94 if ((fd = o_gethandle()) == -1) { 95 errno = EMFILE; 96 return(-1); 97 } 98 99 f = &files[fd]; 100 f->f_flags = mode + 1; 101 f->f_dev = NULL; 102 f->f_ops = NULL; 103 f->f_offset = 0; 104 f->f_devdata = NULL; 105 f->f_fsdata = NULL; 106 file = NULL; 107 error = devopen(f, fname, &file); 108 if (error || f->f_dev == NULL) 109 goto err; 110 111 /* see if we opened a raw device; otherwise, 'file' is the file name. */ 112 if (file == NULL || *file == '\0') { 113 f->f_flags |= F_RAW; 114 return (fd); 115 } 116 117 /* pass file name to the different filesystem open routines */ 118 besterror = ENOENT; 119 for (i = 0; file_system[i] != NULL; i++) { 120 error = ((*file_system[i]).fo_open)(file, f); 121 if (error == 0) { 122 f->f_ops = file_system[i]; 123 o_rainit(f); 124 return (fd); 125 } 126 if (error != EINVAL) 127 besterror = error; 128 } 129 error = besterror; 130 131 if (f->f_dev) 132 f->f_dev->dv_close(f); 133 if (error) 134 devclose(f); 135 136 err: 137 f->f_flags = 0; 138 errno = error; 139 return (-1); 140 } 141