2 * Copyright (c) 1983, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Edward Wang at The University of California, Berkeley.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#)wwiomux.c 8.1 (Berkeley) 6/6/93
37 * $FreeBSD: src/usr.bin/window/wwiomux.c,v 1.1.1.1.14.1 2001/05/17 09:45:01 obrien Exp $
38 * $DragonFly: src/usr.bin/window/wwiomux.c,v 1.2 2003/06/17 04:29:34 dillon Exp $
43 #include <sys/types.h>
44 #if !defined(OLD_TTY) && !defined(TIOCPKT_DATA)
45 #include <sys/ioctl.h>
50 * Multiple window output handler.
51 * The idea is to copy window outputs to the terminal, via the
52 * display package. We try to give wwcurwin highest priority.
53 * The only return conditions are when there is keyboard input
54 * and when a child process dies, which are serviced by signal
55 * catchers (wwrint() and wwchild()).
56 * When there's nothing to do, we sleep in a select().
57 * This can be done better with interrupt driven io. But that's
58 * not supported on ptys, yet.
59 * The history of this routine is interesting.
63 register struct ww
*w
;
79 for (w
= wwhead
.ww_forw
; w
!= &wwhead
; w
= w
->ww_forw
) {
82 if (w
->ww_obq
< w
->ww_obe
) {
85 FD_SET(w
->ww_pty
, &imask
);
87 if (w
->ww_obq
> w
->ww_obp
&& !w
->ww_stopped
)
96 (void) setjmp(wwjmpbuf
);
104 * Defensive code. If somebody else (for example,
105 * wall) clears the ASYNC flag on us, we will block
106 * forever. So we need a finite timeout and set
107 * the flag again. Anything more clever will probably
108 * need even more system calls. (This is a bug
110 * I don't like this one bit.
112 (void) fcntl(0, F_SETFL
, wwnewtty
.ww_fflags
);
120 n
= select(n
+ 1, &imask
, (fd_set
*)0, (fd_set
*)0, &tv
);
129 for (w
= wwhead
.ww_forw
; w
!= &wwhead
; w
= w
->ww_forw
) {
131 !FD_ISSET(w
->ww_pty
, &imask
))
143 n
= read(w
->ww_pty
, p
, w
->ww_obe
- p
);
146 (void) close(w
->ww_pty
);
150 (void) close(w
->ww_pty
);
152 } else if (!w
->ww_ispty
) {
156 } else if (*p
== TIOCPKT_DATA
) {
163 if (*p
& TIOCPKT_STOP
)
165 if (*p
& TIOCPKT_START
)
167 if (*p
& TIOCPKT_FLUSHWRITE
) {
169 w
->ww_obq
= w
->ww_obp
=
177 * Try the current window first, if there is output
178 * then process it and go back to the top to try again.
179 * This can lead to starvation of the other windows,
180 * but presumably that what we want.
181 * Update will eventually happen when output from wwcurwin
184 if ((w
= wwcurwin
) != 0 && w
->ww_pty
>= 0 &&
185 w
->ww_obq
> w
->ww_obp
&& !w
->ww_stopped
) {
186 n
= wwwrite(w
, w
->ww_obp
, w
->ww_obq
- w
->ww_obp
);
187 if ((w
->ww_obp
+= n
) == w
->ww_obq
)
188 w
->ww_obq
= w
->ww_obp
= w
->ww_ob
;
192 for (w
= wwhead
.ww_forw
; w
!= &wwhead
; w
= w
->ww_forw
)
193 if (w
->ww_pty
>= 0 && w
->ww_obq
> w
->ww_obp
&&
195 n
= wwwrite(w
, w
->ww_obp
,
196 w
->ww_obq
- w
->ww_obp
);
197 if ((w
->ww_obp
+= n
) == w
->ww_obq
)
198 w
->ww_obq
= w
->ww_obp
= w
->ww_ob
;