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authorTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
committerTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
commitd6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch)
treeece253b876159b39c620e62b6c9b1174642e070e /usr.bin/window/wwiomux.c
initial import of NetBSD tree
Diffstat (limited to 'usr.bin/window/wwiomux.c')
-rw-r--r--usr.bin/window/wwiomux.c209
1 files changed, 209 insertions, 0 deletions
diff --git a/usr.bin/window/wwiomux.c b/usr.bin/window/wwiomux.c
new file mode 100644
index 00000000000..6155d5a75b6
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+++ b/usr.bin/window/wwiomux.c
@@ -0,0 +1,209 @@
+/* $NetBSD: wwiomux.c,v 1.3 1995/09/28 10:35:37 tls Exp $ */
+
+/*
+ * Copyright (c) 1983, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Edward Wang at The University of California, Berkeley.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#)wwiomux.c 8.1 (Berkeley) 6/6/93";
+#else
+static char rcsid[] = "$NetBSD: wwiomux.c,v 1.3 1995/09/28 10:35:37 tls Exp $";
+#endif
+#endif /* not lint */
+
+#include "ww.h"
+#include <sys/time.h>
+#include <sys/types.h>
+#if !defined(OLD_TTY) && !defined(TIOCPKT_DATA)
+#include <sys/ioctl.h>
+#endif
+#include <fcntl.h>
+
+/*
+ * Multiple window output handler.
+ * The idea is to copy window outputs to the terminal, via the
+ * display package. We try to give wwcurwin highest priority.
+ * The only return conditions are when there is keyboard input
+ * and when a child process dies, which are serviced by signal
+ * catchers (wwrint() and wwchild()).
+ * When there's nothing to do, we sleep in a select().
+ * This can be done better with interrupt driven io. But that's
+ * not supported on ptys, yet.
+ * The history of this routine is interesting.
+ */
+wwiomux()
+{
+ register struct ww *w;
+ fd_set imask;
+ register n;
+ register char *p;
+ char c;
+ struct timeval tv;
+ char noblock = 0;
+
+ for (;;) {
+ if (wwinterrupt()) {
+ wwclrintr();
+ return;
+ }
+
+ FD_ZERO(&imask);
+ n = -1;
+ for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw) {
+ if (w->ww_pty < 0)
+ continue;
+ if (w->ww_obq < w->ww_obe) {
+ if (w->ww_pty > n)
+ n = w->ww_pty;
+ FD_SET(w->ww_pty, &imask);
+ }
+ if (w->ww_obq > w->ww_obp && !w->ww_stopped)
+ noblock = 1;
+ }
+
+ if (!noblock) {
+ if (wwcurwin != 0)
+ wwcurtowin(wwcurwin);
+ wwupdate();
+ wwflush();
+ (void) setjmp(wwjmpbuf);
+ wwsetjmp = 1;
+ if (wwinterrupt()) {
+ wwsetjmp = 0;
+ wwclrintr();
+ return;
+ }
+ /*
+ * Defensive code. If somebody else (for example,
+ * wall) clears the ASYNC flag on us, we will block
+ * forever. So we need a finite timeout and set
+ * the flag again. Anything more clever will probably
+ * need even more system calls. (This is a bug
+ * in the kernel.)
+ * I don't like this one bit.
+ */
+ (void) fcntl(0, F_SETFL, wwnewtty.ww_fflags);
+ tv.tv_sec = 30;
+ tv.tv_usec = 0;
+ } else {
+ tv.tv_sec = 0;
+ tv.tv_usec = 10000;
+ }
+ wwnselect++;
+ n = select(n + 1, &imask, (fd_set *)0, (fd_set *)0, &tv);
+ wwsetjmp = 0;
+ noblock = 0;
+
+ if (n < 0)
+ wwnselecte++;
+ else if (n == 0)
+ wwnselectz++;
+ else
+ for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw) {
+ if (w->ww_pty < 0 ||
+ !FD_ISSET(w->ww_pty, &imask))
+ continue;
+ wwnwread++;
+ p = w->ww_obq;
+ if (w->ww_ispty) {
+ if (p == w->ww_ob) {
+ w->ww_obp++;
+ w->ww_obq++;
+ } else
+ p--;
+ c = *p;
+ }
+ n = read(w->ww_pty, p, w->ww_obe - p);
+ if (n < 0) {
+ wwnwreade++;
+ (void) close(w->ww_pty);
+ w->ww_pty = -1;
+ } else if (n == 0) {
+ wwnwreadz++;
+ (void) close(w->ww_pty);
+ w->ww_pty = -1;
+ } else if (!w->ww_ispty) {
+ wwnwreadd++;
+ wwnwreadc += n;
+ w->ww_obq += n;
+ } else if (*p == TIOCPKT_DATA) {
+ n--;
+ wwnwreadd++;
+ wwnwreadc += n;
+ w->ww_obq += n;
+ } else {
+ wwnwreadp++;
+ if (*p & TIOCPKT_STOP)
+ w->ww_stopped = 1;
+ if (*p & TIOCPKT_START)
+ w->ww_stopped = 0;
+ if (*p & TIOCPKT_FLUSHWRITE) {
+ w->ww_stopped = 0;
+ w->ww_obq = w->ww_obp =
+ w->ww_ob;
+ }
+ }
+ if (w->ww_ispty)
+ *p = c;
+ }
+ /*
+ * Try the current window first, if there is output
+ * then process it and go back to the top to try again.
+ * This can lead to starvation of the other windows,
+ * but presumably that what we want.
+ * Update will eventually happen when output from wwcurwin
+ * dies down.
+ */
+ if ((w = wwcurwin) != 0 && w->ww_pty >= 0 &&
+ w->ww_obq > w->ww_obp && !w->ww_stopped) {
+ n = wwwrite(w, w->ww_obp, w->ww_obq - w->ww_obp);
+ if ((w->ww_obp += n) == w->ww_obq)
+ w->ww_obq = w->ww_obp = w->ww_ob;
+ noblock = 1;
+ continue;
+ }
+ for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw)
+ if (w->ww_pty >= 0 && w->ww_obq > w->ww_obp &&
+ !w->ww_stopped) {
+ n = wwwrite(w, w->ww_obp,
+ w->ww_obq - w->ww_obp);
+ if ((w->ww_obp += n) == w->ww_obq)
+ w->ww_obq = w->ww_obp = w->ww_ob;
+ if (wwinterrupt())
+ break;
+ }
+ }
+}