xref: /illumos-gate/usr/src/lib/libc/port/gen/cfsetispeed.c (revision 88f8b78a88cbdc6d8c1af5c3e54bc49d25095c98)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*	Copyright (c) 1988 AT&T	*/
30 /*	  All Rights Reserved  	*/
31 
32 
33 #pragma weak cfsetispeed = _cfsetispeed
34 #include "synonyms.h"
35 #include <sys/types.h>
36 #include <sys/termios.h>
37 
38 /*
39  * sets the input baud rate stored in c_cflag to speed
40  */
41 
42 int
43 cfsetispeed(struct termios *termios_p, speed_t speed)
44 {
45 	/*
46 	 * If the input speed is zero, set it to output speed
47 	 */
48 	if (speed == 0) {
49 		speed = termios_p->c_cflag & CBAUD;
50 		if (termios_p->c_cflag & CBAUDEXT)
51 			speed += (CBAUD + 1);
52 	}
53 
54 	if ((speed << 16) > CIBAUD) {
55 		termios_p->c_cflag |= CIBAUDEXT;
56 		speed -= ((CIBAUD >> 16) + 1);
57 	} else
58 		termios_p->c_cflag &= ~CIBAUDEXT;
59 	termios_p->c_cflag =
60 	    (termios_p->c_cflag & ~CIBAUD) | ((speed << 16) & CIBAUD);
61 	return (0);
62 }
63