163277Smckusick /*-
2*63370Sbostic * Copyright (c) 1993
3*63370Sbostic * The Regents of the University of California. All rights reserved.
463277Smckusick *
563277Smckusick * This code is derived from software contributed to Berkeley by
663277Smckusick * The Mach Operating System project at Carnegie-Mellon University.
763277Smckusick *
863277Smckusick * %sccs.include.redist.c%
963277Smckusick *
10*63370Sbostic * @(#)read.c 8.1 (Berkeley) 06/11/93
1163277Smckusick *
1263277Smckusick *
1363277Smckusick * Copyright (c) 1989, 1990, 1991 Carnegie Mellon University
1463277Smckusick * All Rights Reserved.
1563277Smckusick *
1663277Smckusick * Author: Alessandro Forin
1763277Smckusick *
1863277Smckusick * Permission to use, copy, modify and distribute this software and its
1963277Smckusick * documentation is hereby granted, provided that both the copyright
2063277Smckusick * notice and this permission notice appear in all copies of the
2163277Smckusick * software, derivative works or modified versions, and any portions
2263277Smckusick * thereof, and that both notices appear in supporting documentation.
2363277Smckusick *
2463277Smckusick * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
2563277Smckusick * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
2663277Smckusick * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
2763277Smckusick *
2863277Smckusick * Carnegie Mellon requests users of this software to return to
2963277Smckusick *
3063277Smckusick * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
3163277Smckusick * School of Computer Science
3263277Smckusick * Carnegie Mellon University
3363277Smckusick * Pittsburgh PA 15213-3890
3463277Smckusick *
3563277Smckusick * any improvements or extensions that they make and grant Carnegie the
3663277Smckusick * rights to redistribute these changes.
3763277Smckusick */
3863277Smckusick
3963277Smckusick #include <stand/stand.h>
4063277Smckusick
read(fd,dest,bcount)4163277Smckusick read(fd, dest, bcount)
4263277Smckusick int fd;
4363277Smckusick char *dest;
4463277Smckusick u_int bcount;
4563277Smckusick {
4663277Smckusick register struct open_file *f = &files[fd];
4763277Smckusick u_int resid;
4863277Smckusick
4963277Smckusick if ((unsigned)fd >= SOPEN_MAX || !(f->f_flags & F_READ)) {
5063277Smckusick errno = EBADF;
5163277Smckusick return (-1);
5263277Smckusick }
5363277Smckusick if (f->f_flags & F_RAW) {
5463277Smckusick errno = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
5563277Smckusick (daddr_t)0, bcount, dest, &resid);
5663277Smckusick if (errno)
5763277Smckusick return (-1);
5863277Smckusick return (resid);
5963277Smckusick }
6063277Smckusick resid = bcount;
6163277Smckusick if (errno = (f->f_ops->read)(f, dest, bcount, &resid))
6263277Smckusick return (-1);
6363277Smckusick return (bcount - resid);
6463277Smckusick }
65