1 /*	$OpenBSD: wwflush.c,v 1.8 2003/08/01 22:01:37 david Exp $	*/
2 /*	$NetBSD: wwflush.c,v 1.5 1995/12/21 10:46:08 mycroft Exp $	*/
3 
4 /*
5  * Copyright (c) 1983, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Edward Wang at The University of California, Berkeley.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)wwflush.c	8.1 (Berkeley) 6/6/93";
39 #else
40 static char rcsid[] = "$OpenBSD: wwflush.c,v 1.8 2003/08/01 22:01:37 david Exp $";
41 #endif
42 #endif /* not lint */
43 
44 #include "ww.h"
45 #include "tt.h"
46 #include <sys/signal.h>
47 #include <signal.h>
48 #include <string.h>
49 #include <unistd.h>
50 
wwflush()51 wwflush()
52 {
53 	int row, col;
54 
55 	if ((row = wwcursorrow) < 0)
56 		row = 0;
57 	else if (row >= wwnrow)
58 		row = wwnrow - 1;
59 	if ((col = wwcursorcol) < 0)
60 		col = 0;
61 	else if (col >= wwncol)
62 		col = wwncol - 1;
63 	xxmove(row, col);
64 	if (wwdocheckpoint) {
65 		xxflush(0);
66 		wwcheckpoint();
67 	} else
68 		xxflush(1);
69 }
70 
wwcheckpoint()71 wwcheckpoint()
72 {
73 	sigset_t sigset, osigset;
74 
75 	sigemptyset(&sigset);
76 	sigaddset(&sigset, SIGALRM);
77 	sigprocmask(SIG_BLOCK, &sigset, &osigset);
78 
79 	tt.tt_ack = 0;
80 	do {
81 		(*tt.tt_checkpoint)();
82 #ifndef OLD_TTY
83 		(void) tcdrain(1);
84 #endif
85 		(void) alarm(3);
86 		for (wwdocheckpoint = 0; !wwdocheckpoint && tt.tt_ack == 0;)
87 			sigsuspend(&osigset);
88 	} while (tt.tt_ack == 0);
89 	(void) alarm(0);
90 	wwdocheckpoint = 0;
91 	if (tt.tt_ack < 0) {
92 		wwcopyscreen(wwcs, wwos);
93 		(void) alarm(1);
94 		wwreset();
95 		wwupdate();
96 		wwflush();
97 	} else {
98 		wwcopyscreen(wwos, wwcs);
99 		(void) alarm(3);
100 	}
101 
102 	sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
103 }
104 
105 wwcopyscreen(s1, s2)
106 	union ww_char **s1, **s2;
107 {
108 	int i;
109 	int s = wwncol * sizeof **s1;
110 
111 	for (i = wwnrow; --i >= 0;)
112 		memmove((char *) *s2++, (char *) *s1++, s);
113 }
114 
115 void
wwalarm()116 wwalarm()
117 {
118 	wwdocheckpoint = 1;
119 }
120