Home | History | Annotate | Line # | Download | only in libsa
write.c revision 1.8 
      1 /*	$NetBSD: write.c,v 1.8 1999/03/31 01:50:26 cgd 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. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *	This product includes software developed by the University of
     21  *	California, Berkeley and its contributors.
     22  * 4. Neither the name of the University nor the names of its contributors
     23  *    may be used to endorse or promote products derived from this software
     24  *    without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     36  * SUCH DAMAGE.
     37  *
     38  *	@(#)write.c	8.1 (Berkeley) 6/11/93
     39  *
     40  *
     41  * Copyright (c) 1989, 1990, 1991 Carnegie Mellon University
     42  * All Rights Reserved.
     43  *
     44  * Author: Alessandro Forin
     45  *
     46  * Permission to use, copy, modify and distribute this software and its
     47  * documentation is hereby granted, provided that both the copyright
     48  * notice and this permission notice appear in all copies of the
     49  * software, derivative works or modified versions, and any portions
     50  * thereof, and that both notices appear in supporting documentation.
     51  *
     52  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
     53  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
     54  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
     55  *
     56  * Carnegie Mellon requests users of this software to return to
     57  *
     58  *  Software Distribution Coordinator  or  Software.Distribution (at) CS.CMU.EDU
     59  *  School of Computer Science
     60  *  Carnegie Mellon University
     61  *  Pittsburgh PA 15213-3890
     62  *
     63  * any improvements or extensions that they make and grant Carnegie the
     64  * rights to redistribute these changes.
     65  */
     66 
     67 #include <sys/param.h>
     68 #include "stand.h"
     69 
     70 ssize_t
     71 write(fd, dest, bcount)
     72 	int fd;
     73 	void *dest;
     74 	size_t bcount;
     75 {
     76 	register struct open_file *f = &files[fd];
     77 	size_t resid;
     78 
     79 #if !defined(LIBSA_NO_FD_CHECKING)
     80 	if ((unsigned)fd >= SOPEN_MAX || !(f->f_flags & F_WRITE)) {
     81 		errno = EBADF;
     82 		return (-1);
     83 	}
     84 #endif
     85 #if !defined(LIBSA_NO_RAW_ACCESS)
     86 	if (f->f_flags & F_RAW) {
     87 #if !defined(LIBSA_NO_TWIDDLE)
     88 		twiddle();
     89 #endif
     90 		errno = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_WRITE,
     91 			btodb(f->f_offset), bcount, dest, &resid);
     92 		if (errno)
     93 			return (-1);
     94 		f->f_offset += resid;
     95 		return (resid);
     96 	}
     97 #endif
     98 	resid = bcount;
     99 	if ((errno = FS_WRITE(f->f_ops)(f, dest, bcount, &resid)))
    100 		return (-1);
    101 	return (0);
    102 }
    103