f75474d6afaee92fe9c76e82d7c3c3e4776f648c
[dragonfly.git] / usr.bin / window / wwiomux.c
1 /*      $NetBSD: wwiomux.c,v 1.14 2009/04/14 08:50:06 lukem Exp $       */
2
3 /*
4  * Copyright (c) 1983, 1993
5  *      The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Edward Wang at The University of California, Berkeley.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34
35 #include <sys/cdefs.h>
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)wwiomux.c   8.1 (Berkeley) 6/6/93";
39 #else
40 __RCSID("$NetBSD: wwiomux.c,v 1.14 2009/04/14 08:50:06 lukem Exp $");
41 #endif
42 #endif /* not lint */
43
44 #include <sys/types.h>
45 #if !defined(OLD_TTY) && !defined(TIOCPKT_DATA)
46 #include <sys/ioctl.h>
47 #endif
48 #include <sys/time.h>
49 #include <poll.h>
50 #include <stdlib.h>
51 #include <fcntl.h>
52 #include <string.h>
53 #include <unistd.h>
54 #include <err.h>
55 #include "ww.h"
56
57 /*
58  * Multiple window output handler.
59  * The idea is to copy window outputs to the terminal, via the
60  * display package.  We try to give wwcurwin highest priority.
61  * The only return conditions are when there is keyboard input
62  * and when a child process dies.
63  * When there's nothing to do, we sleep in a select().
64  * The history of this routine is interesting.
65  */
66 void
67 wwiomux(void)
68 {
69         struct ww *w;
70         nfds_t nfd;
71         int i;
72         int volatile dostdin;   /* avoid longjmp clobbering */
73         char volatile c;        /* avoid longjmp clobbering */
74         char *p;
75         int millis;
76         char noblock = 0;
77         static struct pollfd *pfd = NULL;
78         static nfds_t maxfds = 0;
79
80         c = 0;  /* XXXGCC -Wuninitialized */
81
82         for (;;) {
83                 if (wwinterrupt()) {
84                         wwclrintr();
85                         return;
86                 }
87
88                 nfd = 0;
89                 for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw) {
90                         if (w->ww_pty < 0 || w->ww_obq >= w->ww_obe)
91                                 continue;
92                         nfd++;
93                 }
94
95                 if (maxfds <= ++nfd) {  /* One more for the fd=0 case below */
96                         struct pollfd *npfd = pfd == NULL ?
97                             malloc(sizeof(*pfd) * nfd) :
98                            realloc(pfd, sizeof(*pfd) * nfd);
99                         if (npfd == NULL) {
100                                 warn("will retry");
101                                 if (pfd)
102                                         free(pfd);
103                                 pfd = NULL;
104                                 maxfds = 0;
105                                 return;
106                         }
107                         pfd = npfd;
108                         maxfds = nfd;
109                 }
110
111                 nfd = 0;
112                 for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw) {
113                         if (w->ww_pty < 0)
114                                 continue;
115                         if (w->ww_obq < w->ww_obe) {
116                                 pfd[nfd].fd = w->ww_pty;
117                                 pfd[nfd++].events = POLLIN;
118                         }
119                         if (w->ww_obq > w->ww_obp &&
120                             !ISSET(w->ww_pflags, WWP_STOPPED))
121                                 noblock = 1;
122                 }
123                 if (wwibq < wwibe) {
124                         dostdin = nfd;
125                         pfd[nfd].fd = 0;
126                         pfd[nfd++].events = POLLIN;
127                 } else {
128                         dostdin = -1;
129                 }
130
131                 if (!noblock) {
132                         if (wwcurwin != 0)
133                                 wwcurtowin(wwcurwin);
134                         wwupdate();
135                         wwflush();
136                         (void) setjmp(wwjmpbuf);
137                         wwsetjmp = 1;
138                         if (wwinterrupt()) {
139                                 wwsetjmp = 0;
140                                 wwclrintr();
141                                 return;
142                         }
143                         /* XXXX */
144                         millis = 30000;
145                 } else {
146                         millis = 10;
147                 }
148                 wwnselect++;
149                 i = poll(pfd, nfd, millis);
150                 wwsetjmp = 0;
151                 noblock = 0;
152
153                 if (i < 0)
154                         wwnselecte++;
155                 else if (i == 0)
156                         wwnselectz++;
157                 else {
158                         if (dostdin != -1 && (pfd[dostdin].revents & POLLIN) != 0)
159                                 wwrint();
160
161                         nfd = 0;
162                         for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw) {
163                                 int n;
164
165                                 if (w->ww_pty < 0)
166                                         continue;
167                                 if (w->ww_pty != pfd[nfd].fd)
168                                         continue;
169                                 if ((pfd[nfd++].revents & POLLIN) == 0)
170                                         continue;
171                                 wwnwread++;
172                                 p = w->ww_obq;
173                                 if (w->ww_type == WWT_PTY) {
174                                         if (p == w->ww_ob) {
175                                                 w->ww_obp++;
176                                                 w->ww_obq++;
177                                         } else
178                                                 p--;
179                                         c = *p;
180                                 }
181                                 n = read(w->ww_pty, p, w->ww_obe - p);
182                                 if (n < 0) {
183                                         wwnwreade++;
184                                         (void) close(w->ww_pty);
185                                         w->ww_pty = -1;
186                                 } else if (n == 0) {
187                                         wwnwreadz++;
188                                         (void) close(w->ww_pty);
189                                         w->ww_pty = -1;
190                                 } else if (w->ww_type != WWT_PTY) {
191                                         wwnwreadd++;
192                                         wwnwreadc += n;
193                                         w->ww_obq += n;
194                                 } else if (*p == TIOCPKT_DATA) {
195                                         n--;
196                                         wwnwreadd++;
197                                         wwnwreadc += n;
198                                         w->ww_obq += n;
199                                 } else {
200                                         wwnwreadp++;
201                                         if (*p & TIOCPKT_STOP)
202                                                 SET(w->ww_pflags, WWP_STOPPED);
203                                         if (*p & TIOCPKT_START)
204                                                 CLR(w->ww_pflags, WWP_STOPPED);
205                                         if (*p & TIOCPKT_FLUSHWRITE) {
206                                                 CLR(w->ww_pflags, WWP_STOPPED);
207                                                 w->ww_obq = w->ww_obp =
208                                                         w->ww_ob;
209                                         }
210                                 }
211                                 if (w->ww_type == WWT_PTY)
212                                         *p = c;
213                         }
214                 }
215                 /*
216                  * Try the current window first, if there is output
217                  * then process it and go back to the top to try again.
218                  * This can lead to starvation of the other windows,
219                  * but presumably that what we want.
220                  * Update will eventually happen when output from wwcurwin
221                  * dies down.
222                  */
223                 if ((w = wwcurwin) != 0 && w->ww_pty >= 0 &&
224                     w->ww_obq > w->ww_obp &&
225                     !ISSET(w->ww_pflags, WWP_STOPPED)) {
226                         int n = wwwrite(w, w->ww_obp, w->ww_obq - w->ww_obp);
227                         if ((w->ww_obp += n) == w->ww_obq)
228                                 w->ww_obq = w->ww_obp = w->ww_ob;
229                         noblock = 1;
230                         continue;
231                 }
232                 for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw)
233                         if (w->ww_pty >= 0 && w->ww_obq > w->ww_obp &&
234                             !ISSET(w->ww_pflags, WWP_STOPPED)) {
235                                 int n = wwwrite(w, w->ww_obp,
236                                         w->ww_obq - w->ww_obp);
237                                 if ((w->ww_obp += n) == w->ww_obq)
238                                         w->ww_obq = w->ww_obp = w->ww_ob;
239                                 if (wwinterrupt())
240                                         break;
241                         }
242         }
243 }