xref: /illumos-gate/usr/src/lib/libxcurses2/src/libc/xcurses/wtimeout.c (revision 59d65d3175825093531e82f44269d948ed510a00)
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 (c) 1995-1998, 2000 by Sun Microsystems, Inc.
24  * All rights reserved.
25  */
26 
27 /* LINTLIBRARY */
28 
29 /*
30  * wtimeout.c
31  *
32  * XCurses Library
33  *
34  * Copyright 1990, 1994 by Mortice Kern Systems Inc.  All rights reserved.
35  *
36  */
37 
38 #ifdef M_RCSID
39 #ifndef lint
40 static char rcsID[] = "$Header: /rd/src/libc/xcurses/rcs/wtimeout.c 1.1 "
41 "1995/06/19 16:12:14 ant Exp $";
42 #endif
43 #endif
44 
45 #include <private.h>
46 
47 /*
48  * Set blocking or non-blocking read for a specified window.
49  * The delay is in milliseconds.
50  */
51 void
52 wtimeout(WINDOW *w, int delay)
53 {
54 	if (delay < 0) {
55 		/* Blocking mode */
56 		w->_vmin = 1;
57 		w->_vtime = 0;
58 	} else {
59 		/* Non-Block (0 == delay) and delayed (0 < delay) */
60 		w->_vmin = 0;
61 
62 		/*
63 		 * VTIME is in 1/10 of second
64 		 * w->_vtime value will be set to termios.c_cc[VMIN].
65 		 * Since c_cc[VMIN] is an unsigned char type, the value
66 		 * to be set needs to be smaller than or equal to 255.
67 		 * Also 'delay' is in milliseconds, so it is rounted up
68 		 * to the nearest 10th of a second.  Only when 'delay' is
69 		 * equal to 0, w->_vtime should become 0; otherwise,
70 		 * it should become a positive value.  The previous version
71 		 * of this code was using the expression "(delay + 50) /100",
72 		 * which was incorrect.
73 		 */
74 		w->_vtime = (delay > 25500) ? 255 : (delay + 99) / 100;
75 	}
76 }
77