window/wwiomux.c

   1 /*      $NetBSD: wwiomux.c,v 1.6 1997/11/21 08:37:30 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. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *      This product includes software developed by the University of
  21  *      California, Berkeley and its contributors.
  22  * 4. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  */
  38
  39 #include <sys/cdefs.h>
  40 #ifndef lint
  41 #if 0
  42 static char sccsid[] = "@(#)wwiomux.c   8.1 (Berkeley) 6/6/93";
  43 #else
  44 __RCSID("$NetBSD: wwiomux.c,v 1.6 1997/11/21 08:37:30 lukem Exp $");
  45 #endif
  46 #endif /* not lint */
  47
  48 #include <sys/types.h>
  49 #if !defined(OLD_TTY) && !defined(TIOCPKT_DATA)
  50 #include <sys/ioctl.h>
  51 #endif
  52 #include <sys/time.h>
  53 #include <fcntl.h>
  54 #include <string.h>
  55 #include <unistd.h>
  56 #include "ww.h"
  57
  58 /*
  59  * Multiple window output handler.
  60  * The idea is to copy window outputs to the terminal, via the
  61  * display package.  We try to give wwcurwin highest priority.
  62  * The only return conditions are when there is keyboard input
  63  * and when a child process dies.
  64  * When there's nothing to do, we sleep in a select().
  65  * The history of this routine is interesting.
  66  */
  67 void
  68 wwiomux()
  69 {
  70         struct ww *w;
  71         fd_set imask;
  72         volatile int n;
  73         char *p;
  74         char c;
  75         struct timeval tv;
  76         char noblock = 0;
  77
  78         for (;;) {
  79                 if (wwinterrupt()) {
  80                         wwclrintr();
  81                         return;
  82                 }
  83
  84                 FD_ZERO(&imask);
  85                 n = -1;
  86                 for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw) {
  87                         if (w->ww_pty < 0)
  88                                 continue;
  89                         if (w->ww_obq < w->ww_obe) {
  90                                 if (w->ww_pty > n)
  91                                         n = w->ww_pty + 1;
  92                                 FD_SET(w->ww_pty, &imask);
  93                         }
  94                         if (w->ww_obq > w->ww_obp &&
  95                             !ISSET(w->ww_pflags, WWP_STOPPED))
  96                                 noblock = 1;
  97                 }
  98                 if (wwibq < wwibe) {
  99                         if (0 > n)
 100                                 n = 0 + 1;
 101                         FD_SET(0, &imask);
 102                 }
 103
 104                 if (!noblock) {
 105                         if (wwcurwin != 0)
 106                                 wwcurtowin(wwcurwin);
 107                         wwupdate();
 108                         wwflush();
 109                         (void) setjmp(wwjmpbuf);
 110                         wwsetjmp = 1;
 111                         if (wwinterrupt()) {
 112                                 wwsetjmp = 0;
 113                                 wwclrintr();
 114                                 return;
 115                         }
 116                         /* XXXX */
 117                         tv.tv_sec = 30;
 118                         tv.tv_usec = 0;
 119                 } else {
 120                         tv.tv_sec = 0;
 121                         tv.tv_usec = 10000;
 122                 }
 123                 wwnselect++;
 124                 n = select(n + 1, &imask, (fd_set *)0, (fd_set *)0, &tv);
 125                 wwsetjmp = 0;
 126                 noblock = 0;
 127
 128                 if (n < 0)
 129                         wwnselecte++;
 130                 else if (n == 0)
 131                         wwnselectz++;
 132                 else {
 133                         if (FD_ISSET(0, &imask))
 134                                 wwrint();
 135                         for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw) {
 136                                 if (w->ww_pty < 0 ||
 137                                     !FD_ISSET(w->ww_pty, &imask))
 138                                         continue;
 139                                 wwnwread++;
 140                                 p = w->ww_obq;
 141                                 if (w->ww_type == WWT_PTY) {
 142                                         if (p == w->ww_ob) {
 143                                                 w->ww_obp++;
 144                                                 w->ww_obq++;
 145                                         } else
 146                                                 p--;
 147                                         c = *p;
 148                                 }
 149                                 n = read(w->ww_pty, p, w->ww_obe - p);
 150                                 if (n < 0) {
 151                                         wwnwreade++;
 152                                         (void) close(w->ww_pty);
 153                                         w->ww_pty = -1;
 154                                 } else if (n == 0) {
 155                                         wwnwreadz++;
 156                                         (void) close(w->ww_pty);
 157                                         w->ww_pty = -1;
 158                                 } else if (w->ww_type != WWT_PTY) {
 159                                         wwnwreadd++;
 160                                         wwnwreadc += n;
 161                                         w->ww_obq += n;
 162                                 } else if (*p == TIOCPKT_DATA) {
 163                                         n--;
 164                                         wwnwreadd++;
 165                                         wwnwreadc += n;
 166                                         w->ww_obq += n;
 167                                 } else {
 168                                         wwnwreadp++;
 169                                         if (*p & TIOCPKT_STOP)
 170                                                 SET(w->ww_pflags, WWP_STOPPED);
 171                                         if (*p & TIOCPKT_START)
 172                                                 CLR(w->ww_pflags, WWP_STOPPED);
 173                                         if (*p & TIOCPKT_FLUSHWRITE) {
 174                                                 CLR(w->ww_pflags, WWP_STOPPED);
 175                                                 w->ww_obq = w->ww_obp =
 176                                                         w->ww_ob;
 177                                         }
 178                                 }
 179                         }
 180                 }
 181                 /*
 182                  * Try the current window first, if there is output
 183                  * then process it and go back to the top to try again.
 184                  * This can lead to starvation of the other windows,
 185                  * but presumably that what we want.
 186                  * Update will eventually happen when output from wwcurwin
 187                  * dies down.
 188                  */
 189                 if ((w = wwcurwin) != 0 && w->ww_pty >= 0 &&
 190                     w->ww_obq > w->ww_obp &&
 191                     !ISSET(w->ww_pflags, WWP_STOPPED)) {
 192                         n = wwwrite(w, w->ww_obp, w->ww_obq - w->ww_obp);
 193                         if ((w->ww_obp += n) == w->ww_obq)
 194                                 w->ww_obq = w->ww_obp = w->ww_ob;
 195                         noblock = 1;
 196                         continue;
 197                 }
 198                 for (w = wwhead.ww_forw; w != &wwhead; w = w->ww_forw)
 199                         if (w->ww_pty >= 0 && w->ww_obq > w->ww_obp &&
 200                             !ISSET(w->ww_pflags, WWP_STOPPED)) {
 201                                 n = wwwrite(w, w->ww_obp,
 202                                         w->ww_obq - w->ww_obp);
 203                                 if ((w->ww_obp += n) == w->ww_obq)
 204                                         w->ww_obq = w->ww_obp = w->ww_ob;
 205                                 if (wwinterrupt())
 206                                         break;
 207                         }
 208         }
 209 }