xref: /dragonfly/usr.bin/bc/tty.c (revision ffe53622)
1 /*      $OpenBSD: tty.c,v 1.1 2013/09/19 16:12:01 otto Exp $	*/
2 
3 /*
4  * Copyright (c) 2013, Otto Moerbeek <otto@drijf.net>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <errno.h>
20 #include <signal.h>
21 #include <histedit.h>
22 #include <termios.h>
23 #include "extern.h"
24 
25 struct termios ttysaved, ttyedit;
26 
27 static int settty(struct termios *);
28 
29 static int
30 settty(struct termios *t)
31 {
32 	int ret;
33 
34 	while ((ret = tcsetattr(0, TCSADRAIN,  t)) == -1 && errno == EINTR)
35 		continue;
36 	return ret;
37 }
38 
39 int
40 gettty(struct termios *t)
41 {
42 	int ret;
43 
44 	while ((ret = tcgetattr(0, t) == -1) && errno == EINTR)
45 		continue;
46 	return ret;
47 }
48 
49 /* ARGSUSED */
50 void
51 tstpcont(int sig)
52 {
53 	int save_errno = errno;
54 
55 	if (sig == SIGTSTP) {
56 		signal(SIGCONT, tstpcont);
57 		gettty(&ttyedit);
58 		settty(&ttysaved);
59 	} else {
60 		signal(SIGTSTP, tstpcont);
61 		settty(&ttyedit);
62 	}
63 	signal(sig, SIG_DFL);
64 	kill(0, sig);
65 	errno = save_errno;
66 }
67