1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Edward Wang at The University of California, Berkeley. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)xxflush.c 8.1 (Berkeley) 6/6/93 37 * $FreeBSD: src/usr.bin/window/xxflush.c,v 1.1.1.1.14.1 2001/05/17 09:45:02 obrien Exp $ 38 * $DragonFly: src/usr.bin/window/xxflush.c,v 1.2 2003/06/17 04:29:34 dillon Exp $ 39 */ 40 41 #include "ww.h" 42 #include "xx.h" 43 #include "tt.h" 44 45 xxflush(intr) 46 register intr; 47 { 48 register struct xx *xp, *xq; 49 50 for (xp = xx_head; xp != 0 && !(intr && wwinterrupt()); xp = xq) { 51 switch (xp->cmd) { 52 case xc_move: 53 if (xp->link == 0) 54 (*tt.tt_move)(xp->arg0, xp->arg1); 55 break; 56 case xc_scroll: 57 xxflush_scroll(xp); 58 break; 59 case xc_inschar: 60 (*tt.tt_move)(xp->arg0, xp->arg1); 61 tt.tt_nmodes = xp->arg3; 62 (*tt.tt_inschar)(xp->arg2); 63 break; 64 case xc_insspace: 65 (*tt.tt_move)(xp->arg0, xp->arg1); 66 (*tt.tt_insspace)(xp->arg2); 67 break; 68 case xc_delchar: 69 (*tt.tt_move)(xp->arg0, xp->arg1); 70 (*tt.tt_delchar)(xp->arg2); 71 break; 72 case xc_clear: 73 (*tt.tt_clear)(); 74 break; 75 case xc_clreos: 76 (*tt.tt_move)(xp->arg0, xp->arg1); 77 (*tt.tt_clreos)(); 78 break; 79 case xc_clreol: 80 (*tt.tt_move)(xp->arg0, xp->arg1); 81 (*tt.tt_clreol)(); 82 break; 83 case xc_write: 84 (*tt.tt_move)(xp->arg0, xp->arg1); 85 tt.tt_nmodes = xp->arg3; 86 (*tt.tt_write)(xp->buf, xp->arg2); 87 break; 88 } 89 xq = xp->link; 90 xxfree(xp); 91 } 92 if ((xx_head = xp) == 0) { 93 xx_tail = 0; 94 xxbufp = xxbuf; 95 } 96 ttflush(); 97 } 98 99 xxflush_scroll(xp) 100 register struct xx *xp; 101 { 102 register struct xx *xq; 103 104 top: 105 if (xp->arg0 == 0) 106 return; 107 /* 108 * We handle retain (da and db) by putting the burden on scrolling up, 109 * which is the less common operation. It must ensure that 110 * text is not pushed below the screen, so scrolling down doesn't 111 * have to worry about it. 112 * 113 * Try scrolling region (or scrolling the whole screen) first. 114 * Can we assume "sr" doesn't push text below the screen 115 * so we don't have to worry about retain below? 116 * What about scrolling down with a newline? It probably does 117 * push text above (with da). Scrolling up would then have 118 * to take care of that. 119 * It's easy to be fool proof, but that slows things down. 120 * The current solution is to disallow tt_scroll_up if da or db is true 121 * but cs (scrolling region) is not. Again, we sacrifice scrolling 122 * up in favor of scrolling down. The idea is having scrolling regions 123 * probably means we can scroll (even the whole screen) with impunity. 124 * This lets us work efficiently on simple terminals (use newline 125 * on the bottom to scroll), on any terminal without retain, and 126 * on vt100 style scrolling regions (I think). 127 */ 128 if (xp->arg0 > 0) { 129 if ((xq = xp->link) != 0 && xq->cmd == xc_scroll && 130 xp->arg2 == xq->arg2 && xq->arg0 < 0) { 131 if (xp->arg1 < xq->arg1) { 132 if (xp->arg2 - xp->arg0 <= xq->arg1) { 133 xq->arg0 = xp->arg0; 134 xq->arg1 = xp->arg1; 135 xq->arg2 = xp->arg2; 136 return; 137 } 138 xp->arg2 = xq->arg1 + xp->arg0; 139 xq->arg0 += xp->arg0; 140 xq->arg1 = xp->arg2; 141 if (xq->arg0 > 0) 142 xq->arg1 -= xq->arg0; 143 goto top; 144 } else { 145 if (xp->arg1 - xq->arg0 >= xp->arg2) 146 return; 147 xq->arg2 = xp->arg1 - xq->arg0; 148 xp->arg0 += xq->arg0; 149 xp->arg1 = xq->arg2; 150 if (xp->arg0 < 0) 151 xp->arg1 += xp->arg0; 152 goto top; 153 } 154 } 155 if (xp->arg0 > xp->arg2 - xp->arg1) 156 xp->arg0 = xp->arg2 - xp->arg1; 157 if (tt.tt_scroll_down) { 158 if (tt.tt_scroll_top != xp->arg1 || 159 tt.tt_scroll_bot != xp->arg2 - 1) { 160 if (tt.tt_setscroll == 0) 161 goto down; 162 (*tt.tt_setscroll)(xp->arg1, xp->arg2 - 1); 163 } 164 tt.tt_scroll_down(xp->arg0); 165 } else { 166 down: 167 (*tt.tt_move)(xp->arg1, 0); 168 (*tt.tt_delline)(xp->arg0); 169 if (xp->arg2 < tt.tt_nrow) { 170 (*tt.tt_move)(xp->arg2 - xp->arg0, 0); 171 (*tt.tt_insline)(xp->arg0); 172 } 173 } 174 } else { 175 xp->arg0 = - xp->arg0; 176 if (xp->arg0 > xp->arg2 - xp->arg1) 177 xp->arg0 = xp->arg2 - xp->arg1; 178 if (tt.tt_scroll_up) { 179 if (tt.tt_scroll_top != xp->arg1 || 180 tt.tt_scroll_bot != xp->arg2 - 1) { 181 if (tt.tt_setscroll == 0) 182 goto up; 183 (*tt.tt_setscroll)(xp->arg1, xp->arg2 - 1); 184 } 185 tt.tt_scroll_up(xp->arg0); 186 } else { 187 up: 188 if (tt.tt_retain || xp->arg2 != tt.tt_nrow) { 189 (*tt.tt_move)(xp->arg2 - xp->arg0, 0); 190 (*tt.tt_delline)(xp->arg0); 191 } 192 (*tt.tt_move)(xp->arg1, 0); 193 (*tt.tt_insline)(xp->arg0); 194 } 195 } 196 } 197