usr.bin/window/xxflush.c

   1 /*      $NetBSD: xxflush.c,v 1.6 2003/08/07 11:17:47 agc Exp $  */
   2
   3 /*
   4  * Copyright (c) 1989, 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[] = "@(#)xxflush.c   8.1 (Berkeley) 6/6/93";
  39 #else
  40 __RCSID("$NetBSD: xxflush.c,v 1.6 2003/08/07 11:17:47 agc Exp $");
  41 #endif
  42 #endif /* not lint */
  43
  44 #include "ww.h"
  45 #include "xx.h"
  46 #include "tt.h"
  47
  48 void
  49 xxflush(int intr)
  50 {
  51         struct xx *xp, *xq;
  52
  53         for (xp = xx_head; xp != 0 && !(intr && wwinterrupt()); xp = xq) {
  54                 switch (xp->cmd) {
  55                 case xc_move:
  56                         if (xp->link == 0)
  57                                 (*tt.tt_move)(xp->arg0, xp->arg1);
  58                         break;
  59                 case xc_scroll:
  60                         xxflush_scroll(xp);
  61                         break;
  62                 case xc_inschar:
  63                         (*tt.tt_move)(xp->arg0, xp->arg1);
  64                         tt.tt_nmodes = xp->arg3;
  65                         (*tt.tt_inschar)(xp->arg2);
  66                         break;
  67                 case xc_insspace:
  68                         (*tt.tt_move)(xp->arg0, xp->arg1);
  69                         (*tt.tt_insspace)(xp->arg2);
  70                         break;
  71                 case xc_delchar:
  72                         (*tt.tt_move)(xp->arg0, xp->arg1);
  73                         (*tt.tt_delchar)(xp->arg2);
  74                         break;
  75                 case xc_clear:
  76                         (*tt.tt_clear)();
  77                         break;
  78                 case xc_clreos:
  79                         (*tt.tt_move)(xp->arg0, xp->arg1);
  80                         (*tt.tt_clreos)();
  81                         break;
  82                 case xc_clreol:
  83                         (*tt.tt_move)(xp->arg0, xp->arg1);
  84                         (*tt.tt_clreol)();
  85                         break;
  86                 case xc_write:
  87                         (*tt.tt_move)(xp->arg0, xp->arg1);
  88                         tt.tt_nmodes = xp->arg3;
  89                         (*tt.tt_write)(xp->buf, xp->arg2);
  90                         break;
  91                 }
  92                 xq = xp->link;
  93                 xxfree(xp);
  94         }
  95         if ((xx_head = xp) == 0) {
  96                 xx_tail = 0;
  97                 xxbufp = xxbuf;
  98         }
  99         ttflush();
 100 }
 101
 102 void
 103 xxflush_scroll(struct xx *xp)
 104 {
 105         struct xx *xq;
 106
 107  top:
 108         if (xp->arg0 == 0)
 109                 return;
 110         /*
 111          * We handle retain (da and db) by putting the burden on scrolling up,
 112          * which is the less common operation.  It must ensure that
 113          * text is not pushed below the screen, so scrolling down doesn't
 114          * have to worry about it.
 115          *
 116          * Try scrolling region (or scrolling the whole screen) first.
 117          * Can we assume "sr" doesn't push text below the screen
 118          * so we don't have to worry about retain below?
 119          * What about scrolling down with a newline?  It probably does
 120          * push text above (with da).  Scrolling up would then have
 121          * to take care of that.
 122          * It's easy to be fool proof, but that slows things down.
 123          * The current solution is to disallow tt_scroll_up if da or db is true
 124          * but cs (scrolling region) is not.  Again, we sacrifice scrolling
 125          * up in favor of scrolling down.  The idea is having scrolling regions
 126          * probably means we can scroll (even the whole screen) with impunity.
 127          * This lets us work efficiently on simple terminals (use newline
 128          * on the bottom to scroll), on any terminal without retain, and
 129          * on vt100 style scrolling regions (I think).
 130          */
 131         if (xp->arg0 > 0) {
 132                 if ((xq = xp->link) != 0 && xq->cmd == xc_scroll &&
 133                     xp->arg2 == xq->arg2 && xq->arg0 < 0) {
 134                         if (xp->arg1 < xq->arg1) {
 135                                 if (xp->arg2 - xp->arg0 <= xq->arg1) {
 136                                         xq->arg0 = xp->arg0;
 137                                         xq->arg1 = xp->arg1;
 138                                         xq->arg2 = xp->arg2;
 139                                         return;
 140                                 }
 141                                 xp->arg2 = xq->arg1 + xp->arg0;
 142                                 xq->arg0 += xp->arg0;
 143                                 xq->arg1 = xp->arg2;
 144                                 if (xq->arg0 > 0)
 145                                         xq->arg1 -= xq->arg0;
 146                                 goto top;
 147                         } else {
 148                                 if (xp->arg1 - xq->arg0 >= xp->arg2)
 149                                         return;
 150                                 xq->arg2 = xp->arg1 - xq->arg0;
 151                                 xp->arg0 += xq->arg0;
 152                                 xp->arg1 = xq->arg2;
 153                                 if (xp->arg0 < 0)
 154                                         xp->arg1 += xp->arg0;
 155                                 goto top;
 156                         }
 157                 }
 158                 if (xp->arg0 > xp->arg2 - xp->arg1)
 159                         xp->arg0 = xp->arg2 - xp->arg1;
 160                 if (tt.tt_scroll_down) {
 161                         if (tt.tt_scroll_top != xp->arg1 ||
 162                             tt.tt_scroll_bot != xp->arg2 - 1) {
 163                                 if (tt.tt_setscroll == 0)
 164                                         goto down;
 165                                 (*tt.tt_setscroll)(xp->arg1, xp->arg2 - 1);
 166                         }
 167                         tt.tt_scroll_down(xp->arg0);
 168                 } else {
 169                 down:
 170                         (*tt.tt_move)(xp->arg1, 0);
 171                         (*tt.tt_delline)(xp->arg0);
 172                         if (xp->arg2 < tt.tt_nrow) {
 173                                 (*tt.tt_move)(xp->arg2 - xp->arg0, 0);
 174                                 (*tt.tt_insline)(xp->arg0);
 175                         }
 176                 }
 177         } else {
 178                 xp->arg0 = - xp->arg0;
 179                 if (xp->arg0 > xp->arg2 - xp->arg1)
 180                         xp->arg0 = xp->arg2 - xp->arg1;
 181                 if (tt.tt_scroll_up) {
 182                         if (tt.tt_scroll_top != xp->arg1 ||
 183                             tt.tt_scroll_bot != xp->arg2 - 1) {
 184                                 if (tt.tt_setscroll == 0)
 185                                         goto up;
 186                                 (*tt.tt_setscroll)(xp->arg1, xp->arg2 - 1);
 187                         }
 188                         tt.tt_scroll_up(xp->arg0);
 189                 } else  {
 190                 up:
 191                         if (tt.tt_retain || xp->arg2 != tt.tt_nrow) {
 192                                 (*tt.tt_move)(xp->arg2 - xp->arg0, 0);
 193                                 (*tt.tt_delline)(xp->arg0);
 194                         }
 195                         (*tt.tt_move)(xp->arg1, 0);
 196                         (*tt.tt_insline)(xp->arg0);
 197                 }
 198         }
 199 }