Home | History | Annotate | Line # | Download | only in libsa 
      1 /*	$NetBSD: open.c,v 1.26 2007/11/24 13:20:56 isaki 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. Neither the name of the University nor the names of its contributors
     19  *    may be used to endorse or promote products derived from this software
     20  *    without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  *
     34  *	@(#)open.c	8.1 (Berkeley) 6/11/93
     35  *
     36  *
     37  * Copyright (c) 1989, 1990, 1991 Carnegie Mellon University
     38  * All Rights Reserved.
     39  *
     40  * Author: Alessandro Forin
     41  *
     42  * Permission to use, copy, modify and distribute this software and its
     43  * documentation is hereby granted, provided that both the copyright
     44  * notice and this permission notice appear in all copies of the
     45  * software, derivative works or modified versions, and any portions
     46  * thereof, and that both notices appear in supporting documentation.
     47  *
     48  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
     49  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
     50  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
     51  *
     52  * Carnegie Mellon requests users of this software to return to
     53  *
     54  *  Software Distribution Coordinator  or  Software.Distribution (at) CS.CMU.EDU
     55  *  School of Computer Science
     56  *  Carnegie Mellon University
     57  *  Pittsburgh PA 15213-3890
     58  *
     59  * any improvements or extensions that they make and grant Carnegie the
     60  * rights to redistribute these changes.
     61  */
     62 
     63 #include "stand.h"
     64 
     65 /*
     66  *	File primitives proper
     67  */
     68 
     69 #ifdef HELLO_CTAGS
     70 oopen(){}
     71 #endif
     72 
     73 int
     74 #ifndef __INTERNAL_LIBSA_CREAD
     75 open(const char *fname, int mode)
     76 #else
     77 oopen(const char *fname, int mode)
     78 #endif
     79 {
     80 	struct open_file *f;
     81 	int fd, error;
     82 #if !defined(LIBSA_SINGLE_FILESYSTEM)
     83 	int i, besterror;
     84 #endif
     85 	char *file;
     86 
     87 	/* find a free file descriptor */
     88 	for (fd = 0, f = files; fd < SOPEN_MAX; fd++, f++)
     89 		if (f->f_flags == 0)
     90 			goto fnd;
     91 	errno = EMFILE;
     92 	return -1;
     93 fnd:
     94 	/*
     95 	 * Try to open the device.
     96 	 * Convert open mode (0,1,2) to F_READ, F_WRITE.
     97 	 */
     98 	f->f_flags = mode + 1;
     99 #if !defined(LIBSA_SINGLE_DEVICE)
    100 	f->f_dev = (struct devsw *)0;
    101 #endif
    102 #if !defined(LIBSA_SINGLE_FILESYSTEM)
    103 	f->f_ops = (struct fs_ops *)0;
    104 #endif
    105 #if !defined(LIBSA_NO_RAW_ACCESS)
    106 	f->f_offset = 0;
    107 #endif
    108 	file = (char *)0;
    109 	error = devopen(f, fname, &file);
    110 	if (error
    111 #if !defined(LIBSA_SINGLE_DEVICE)
    112 	    || (((f->f_flags & F_NODEV) == 0) &&
    113 		f->f_dev == (struct devsw *)0)
    114 #endif
    115 	    )
    116 		goto err;
    117 
    118 #if !defined(LIBSA_NO_RAW_ACCESS)
    119 	/* see if we opened a raw device; otherwise, 'file' is the file name. */
    120 	if (file == (char *)0 || *file == '\0') {
    121 		f->f_flags |= F_RAW;
    122 		return fd;
    123 	}
    124 #endif
    125 
    126 	/* pass file name to the different filesystem open routines */
    127 #if !defined(LIBSA_SINGLE_FILESYSTEM)
    128 	besterror = ENOENT;
    129 	for (i = 0; i < nfsys; i++) {
    130 		error = FS_OPEN(&file_system[i])(file, f);
    131 		if (error == 0) {
    132 			f->f_ops = &file_system[i];
    133 			return fd;
    134 		}
    135 		if (error != EINVAL)
    136 			besterror = error;
    137 	}
    138 	error = besterror;
    139 #else
    140 	error = FS_OPEN(&file_system[i])(file, f);
    141 	if (error == 0)
    142 		return fd;
    143 	if (error == EINVAL)
    144 		error = ENOENT;
    145 #endif
    146 
    147 	if ((f->f_flags & F_NODEV) == 0) {
    148 #if !defined(LIBSA_SINGLE_DEVICE)
    149 		if (DEV_CLOSE(f->f_dev) != NULL)
    150 #endif
    151 			(void)DEV_CLOSE(f->f_dev)(f);
    152 	}
    153 err:
    154 	f->f_flags = 0;
    155 	errno = error;
    156 	return -1;
    157 }
    158