| 1 | /* @(#)xxflush.c 8.1 (Berkeley) 6/6/93 */ |
| 2 | /* $NetBSD: xxflush.c,v 1.6 2003/08/07 11:17:47 agc Exp $ */ |
| 3 | |
| 4 | /* |
| 5 | * Copyright (c) 1989, 1993 |
| 6 | * The Regents of the University of California. All rights reserved. |
| 7 | * |
| 8 | * This code is derived from software contributed to Berkeley by |
| 9 | * Edward Wang at The University of California, Berkeley. |
| 10 | * |
| 11 | * Redistribution and use in source and binary forms, with or without |
| 12 | * modification, are permitted provided that the following conditions |
| 13 | * are met: |
| 14 | * 1. Redistributions of source code must retain the above copyright |
| 15 | * notice, this list of conditions and the following disclaimer. |
| 16 | * 2. Redistributions in binary form must reproduce the above copyright |
| 17 | * notice, this list of conditions and the following disclaimer in the |
| 18 | * documentation and/or other materials provided with the distribution. |
| 19 | * 3. Neither the name of the University nor the names of its contributors |
| 20 | * may be used to endorse or promote products derived from this software |
| 21 | * without specific prior written permission. |
| 22 | * |
| 23 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 24 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 25 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 26 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 27 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 28 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 29 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 30 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 31 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 32 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 33 | * SUCH DAMAGE. |
| 34 | */ |
| 35 | |
| 36 | #include "ww.h" |
| 37 | #include "xx.h" |
| 38 | #include "tt.h" |
| 39 | |
| 40 | void |
| 41 | xxflush(int intr) |
| 42 | { |
| 43 | struct xx *xp, *xq; |
| 44 | |
| 45 | for (xp = xx_head; xp != 0 && !(intr && wwinterrupt()); xp = xq) { |
| 46 | switch (xp->cmd) { |
| 47 | case xc_move: |
| 48 | if (xp->link == 0) |
| 49 | (*tt.tt_move)(xp->arg0, xp->arg1); |
| 50 | break; |
| 51 | case xc_scroll: |
| 52 | xxflush_scroll(xp); |
| 53 | break; |
| 54 | case xc_inschar: |
| 55 | (*tt.tt_move)(xp->arg0, xp->arg1); |
| 56 | tt.tt_nmodes = xp->arg3; |
| 57 | (*tt.tt_inschar)(xp->arg2); |
| 58 | break; |
| 59 | case xc_insspace: |
| 60 | (*tt.tt_move)(xp->arg0, xp->arg1); |
| 61 | (*tt.tt_insspace)(xp->arg2); |
| 62 | break; |
| 63 | case xc_delchar: |
| 64 | (*tt.tt_move)(xp->arg0, xp->arg1); |
| 65 | (*tt.tt_delchar)(xp->arg2); |
| 66 | break; |
| 67 | case xc_clear: |
| 68 | (*tt.tt_clear)(); |
| 69 | break; |
| 70 | case xc_clreos: |
| 71 | (*tt.tt_move)(xp->arg0, xp->arg1); |
| 72 | (*tt.tt_clreos)(); |
| 73 | break; |
| 74 | case xc_clreol: |
| 75 | (*tt.tt_move)(xp->arg0, xp->arg1); |
| 76 | (*tt.tt_clreol)(); |
| 77 | break; |
| 78 | case xc_write: |
| 79 | (*tt.tt_move)(xp->arg0, xp->arg1); |
| 80 | tt.tt_nmodes = xp->arg3; |
| 81 | (*tt.tt_write)(xp->buf, xp->arg2); |
| 82 | break; |
| 83 | } |
| 84 | xq = xp->link; |
| 85 | xxfree(xp); |
| 86 | } |
| 87 | if ((xx_head = xp) == 0) { |
| 88 | xx_tail = 0; |
| 89 | xxbufp = xxbuf; |
| 90 | } |
| 91 | ttflush(); |
| 92 | } |
| 93 | |
| 94 | void |
| 95 | xxflush_scroll(struct xx *xp) |
| 96 | { |
| 97 | struct xx *xq; |
| 98 | |
| 99 | top: |
| 100 | if (xp->arg0 == 0) |
| 101 | return; |
| 102 | /* |
| 103 | * We handle retain (da and db) by putting the burden on scrolling up, |
| 104 | * which is the less common operation. It must ensure that |
| 105 | * text is not pushed below the screen, so scrolling down doesn't |
| 106 | * have to worry about it. |
| 107 | * |
| 108 | * Try scrolling region (or scrolling the whole screen) first. |
| 109 | * Can we assume "sr" doesn't push text below the screen |
| 110 | * so we don't have to worry about retain below? |
| 111 | * What about scrolling down with a newline? It probably does |
| 112 | * push text above (with da). Scrolling up would then have |
| 113 | * to take care of that. |
| 114 | * It's easy to be fool proof, but that slows things down. |
| 115 | * The current solution is to disallow tt_scroll_up if da or db is true |
| 116 | * but cs (scrolling region) is not. Again, we sacrifice scrolling |
| 117 | * up in favor of scrolling down. The idea is having scrolling regions |
| 118 | * probably means we can scroll (even the whole screen) with impunity. |
| 119 | * This lets us work efficiently on simple terminals (use newline |
| 120 | * on the bottom to scroll), on any terminal without retain, and |
| 121 | * on vt100 style scrolling regions (I think). |
| 122 | */ |
| 123 | if (xp->arg0 > 0) { |
| 124 | if ((xq = xp->link) != 0 && xq->cmd == xc_scroll && |
| 125 | xp->arg2 == xq->arg2 && xq->arg0 < 0) { |
| 126 | if (xp->arg1 < xq->arg1) { |
| 127 | if (xp->arg2 - xp->arg0 <= xq->arg1) { |
| 128 | xq->arg0 = xp->arg0; |
| 129 | xq->arg1 = xp->arg1; |
| 130 | xq->arg2 = xp->arg2; |
| 131 | return; |
| 132 | } |
| 133 | xp->arg2 = xq->arg1 + xp->arg0; |
| 134 | xq->arg0 += xp->arg0; |
| 135 | xq->arg1 = xp->arg2; |
| 136 | if (xq->arg0 > 0) |
| 137 | xq->arg1 -= xq->arg0; |
| 138 | goto top; |
| 139 | } else { |
| 140 | if (xp->arg1 - xq->arg0 >= xp->arg2) |
| 141 | return; |
| 142 | xq->arg2 = xp->arg1 - xq->arg0; |
| 143 | xp->arg0 += xq->arg0; |
| 144 | xp->arg1 = xq->arg2; |
| 145 | if (xp->arg0 < 0) |
| 146 | xp->arg1 += xp->arg0; |
| 147 | goto top; |
| 148 | } |
| 149 | } |
| 150 | if (xp->arg0 > xp->arg2 - xp->arg1) |
| 151 | xp->arg0 = xp->arg2 - xp->arg1; |
| 152 | if (tt.tt_scroll_down) { |
| 153 | if (tt.tt_scroll_top != xp->arg1 || |
| 154 | tt.tt_scroll_bot != xp->arg2 - 1) { |
| 155 | if (tt.tt_setscroll == 0) |
| 156 | goto down; |
| 157 | (*tt.tt_setscroll)(xp->arg1, xp->arg2 - 1); |
| 158 | } |
| 159 | tt.tt_scroll_down(xp->arg0); |
| 160 | } else { |
| 161 | down: |
| 162 | (*tt.tt_move)(xp->arg1, 0); |
| 163 | (*tt.tt_delline)(xp->arg0); |
| 164 | if (xp->arg2 < tt.tt_nrow) { |
| 165 | (*tt.tt_move)(xp->arg2 - xp->arg0, 0); |
| 166 | (*tt.tt_insline)(xp->arg0); |
| 167 | } |
| 168 | } |
| 169 | } else { |
| 170 | xp->arg0 = - xp->arg0; |
| 171 | if (xp->arg0 > xp->arg2 - xp->arg1) |
| 172 | xp->arg0 = xp->arg2 - xp->arg1; |
| 173 | if (tt.tt_scroll_up) { |
| 174 | if (tt.tt_scroll_top != xp->arg1 || |
| 175 | tt.tt_scroll_bot != xp->arg2 - 1) { |
| 176 | if (tt.tt_setscroll == 0) |
| 177 | goto up; |
| 178 | (*tt.tt_setscroll)(xp->arg1, xp->arg2 - 1); |
| 179 | } |
| 180 | tt.tt_scroll_up(xp->arg0); |
| 181 | } else { |
| 182 | up: |
| 183 | if (tt.tt_retain || xp->arg2 != tt.tt_nrow) { |
| 184 | (*tt.tt_move)(xp->arg2 - xp->arg0, 0); |
| 185 | (*tt.tt_delline)(xp->arg0); |
| 186 | } |
| 187 | (*tt.tt_move)(xp->arg1, 0); |
| 188 | (*tt.tt_insline)(xp->arg0); |
| 189 | } |
| 190 | } |
| 191 | } |